/* ==========================================================================
   QueStudy Home — App-Shell Dashboard UI
   Three-column SaaS layout: 280px sidebar / main / 320px right sidebar.
   Theme: light + dark, Inter, blue #2563EB, 16–20px radii, soft shadows.
   ========================================================================== */

:root {
    --qs-app-bg: #eef2f8;
    --qs-app-card: #ffffff;
    --qs-app-card-soft: #f8fafc;
    --qs-app-border: #e4e9f1;
    --qs-app-border-strong: #d7deea;
    --qs-app-text: #0f172a;
    --qs-app-text-soft: #475569;
    --qs-app-muted: #64748b;
    --qs-app-faint: #94a3b8;
    --qs-app-primary: #2563eb;
    --qs-app-primary-dark: #1d4ed8;
    --qs-app-primary-soft: #eff6ff;
    --qs-app-primary-border: #bfdbfe;
    --qs-app-shadow: 0 1px 2px rgba(16, 24, 40, 0.04), 0 1px 3px rgba(16, 24, 40, 0.05);
    --qs-app-shadow-md: 0 6px 16px -6px rgba(15, 23, 42, 0.12);
    --qs-app-shadow-lg: 0 18px 40px -12px rgba(15, 23, 42, 0.18);
    --qs-app-radius: 18px;
    --qs-app-radius-sm: 12px;
    --qs-app-radius-lg: 22px;
    --qs-app-sidebar-w: 280px;
    --qs-app-sidebar-visible: 1;
    --qs-app-topbar-h: 72px;
    --qs-gradient-primary: linear-gradient(135deg, #2563eb 0%, #1d4ed8 100%);
    --qs-gradient-purple: linear-gradient(135deg, #7c3aed 0%, #6d28d9 55%, #4c1d95 100%);
}

html[data-theme="dark"] {
    --qs-app-bg: #0b1220;
    --qs-app-card: #101a2e;
    --qs-app-card-soft: #0d1626;
    --qs-app-border: #1e2a41;
    --qs-app-border-strong: #27344f;
    --qs-app-text: #e6edf7;
    --qs-app-text-soft: #c3cede;
    --qs-app-muted: #94a3b8;
    --qs-app-faint: #64748b;
    --qs-app-primary: #3b82f6;
    --qs-app-primary-dark: #2563eb;
    --qs-app-primary-soft: rgba(59, 130, 246, 0.14);
    --qs-app-primary-border: rgba(59, 130, 246, 0.35);
    --qs-app-shadow: 0 1px 2px rgba(0, 0, 0, 0.35);
    --qs-app-shadow-md: 0 6px 16px -6px rgba(0, 0, 0, 0.5);
    --qs-app-shadow-lg: 0 18px 40px -12px rgba(0, 0, 0, 0.6);
}

/* -------------------------------------------------------------------------
   App shell
   ------------------------------------------------------------------------- */
body.qs-app-shell {
    background: var(--qs-app-bg);
    color: var(--qs-app-text);
    transition: background 0.3s ease, color 0.3s ease;
}

body.qs-app-shell h1,
body.qs-app-shell h2,
body.qs-app-shell h3,
body.qs-app-shell h4 {
    color: var(--qs-app-text);
}

.qs-app { min-height: 100vh; }

/* -------------------------------------------------------------------------
   Left sidebar (280px)
   ------------------------------------------------------------------------- */
.qs-app-sidebar {
    position: fixed;
    top: 0;
    bottom: 0;
    left: 0;
    width: var(--qs-app-sidebar-w);
    background: var(--qs-app-card);
    border-right: 1px solid var(--qs-app-border);
    z-index: 1200;
    transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.qs-sidebar-inner {
    display: flex;
    flex-direction: column;
    height: 100%;
    padding: 22px 16px 18px;
    overflow-y: auto;
    scrollbar-width: thin;
    scrollbar-color: var(--qs-app-border-strong) transparent;
}

.qs-sidebar-top { padding: 0 8px 20px; border-bottom: 1px solid var(--qs-app-border); }

.qs-sidebar-brand {
    display: flex;
    align-items: center;
    gap: 10px;
    text-decoration: none;
}

.qs-sidebar-brand-text { display: flex; flex-direction: column; line-height: 1.15; }
.qs-sidebar-brand-text strong {
    font-size: 1.3rem;
    font-weight: 800;
    letter-spacing: -0.02em;
    color: var(--qs-app-text);
}
.qs-sidebar-brand-text em {
    font-style: normal;
    font-size: 0.72rem;
    font-weight: 600;
    color: var(--qs-app-muted);
    letter-spacing: 0.01em;
}

/* Admin-uploaded logo images */
.qs-sidebar-brand-logo {
    max-height: 38px;
    width: auto;
    height: auto;
    object-fit: contain;
    flex-shrink: 0;
}
.qs-logo-img-footer {
    max-height: 32px;
    width: auto;
    height: auto;
    object-fit: contain;
}
.qs-auth-logo-img {
    max-height: 44px;
    width: auto;
    height: auto;
    object-fit: contain;
}

/* Sidebar navigation */
.qs-sidebar-nav { flex: 1; padding: 16px 0 8px; }

.qs-sidebar-label {
    display: block;
    font-size: 0.68rem;
    font-weight: 700;
    letter-spacing: 0.09em;
    text-transform: uppercase;
    color: var(--qs-app-faint);
    padding: 0 12px 8px;
}

.qs-sidebar-menu { list-style: none; margin: 0; padding: 0; display: flex; flex-direction: column; gap: 2px; }

.qs-smenu-item > a {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 9px 12px;
    border-radius: 12px;
    color: var(--qs-app-text-soft);
    font-size: 0.88rem;
    font-weight: 500;
    text-decoration: none;
    position: relative;
    transition: background 0.18s ease, color 0.18s ease, transform 0.18s ease;
}
.qs-smenu-item > a svg { flex-shrink: 0; opacity: 0.75; transition: opacity 0.18s ease; }
.qs-smenu-item > a:hover { background: var(--qs-app-card-soft); color: var(--qs-app-text); }
.qs-smenu-item > a:hover svg { opacity: 1; }
.qs-smenu-item > a:active { transform: scale(0.98); }

.qs-smenu-text { flex: 1; min-width: 0; }

.qs-badge-new {
    background: var(--qs-gradient-primary);
    color: #fff;
    font-size: 0.6rem;
    font-weight: 800;
    letter-spacing: 0.05em;
    padding: 3px 7px;
    border-radius: 999px;
    flex-shrink: 0;
    animation: qs-pulse-badge 2.4s ease-in-out infinite;
}
html[data-theme="dark"] .qs-badge-new { color: #fff; }

@keyframes qs-pulse-badge {
    0%, 100% { box-shadow: 0 0 0 0 rgba(37, 99, 235, 0.45); }
    50% { box-shadow: 0 0 0 5px rgba(37, 99, 235, 0); }
}

.qs-smenu-active > a {
    background: var(--qs-app-primary-soft);
    color: var(--qs-app-primary);
    font-weight: 700;
}
.qs-smenu-active > a::before {
    content: "";
    position: absolute;
    left: -16px;
    top: 50%;
    transform: translateY(-50%);
    width: 4px;
    height: 26px;
    border-radius: 0 4px 4px 0;
    background: var(--qs-app-primary);
}
.qs-smenu-active > a svg { opacity: 1; color: var(--qs-app-primary); }
.qs-smenu-active > a:hover { background: var(--qs-app-primary-soft); }

/* Sidebar bottom: upgrade + dark mode */
.qs-sidebar-bottom {
    display: flex;
    flex-direction: column;
    gap: 14px;
    padding-top: 14px;
    border-top: 1px solid var(--qs-app-border);
}

.qs-sidebar-upgrade {
    position: relative;
    overflow: hidden;
    background: var(--qs-gradient-primary);
    border-radius: 16px;
    padding: 18px 16px 16px;
    text-align: center;
    color: #fff;
}
.qs-upgrade-glow {
    position: absolute;
    width: 140px;
    height: 140px;
    border-radius: 50%;
    background: radial-gradient(circle, rgba(255, 255, 255, 0.35), transparent 70%);
    top: -60px;
    right: -40px;
    pointer-events: none;
}
.qs-upgrade-icon {
    width: 44px;
    height: 44px;
    margin: 0 auto 10px;
    border-radius: 14px;
    background: rgba(255, 255, 255, 0.18);
    display: grid;
    place-items: center;
    box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.22);
}
.qs-upgrade-title { margin: 0 0 4px; font-size: 0.95rem; font-weight: 800; color: #fff; }
.qs-upgrade-desc { margin: 0 0 12px; font-size: 0.72rem; line-height: 1.45; color: rgba(255, 255, 255, 0.88); }
.qs-sidebar-upgrade .qs-btn { background: #fff; color: var(--qs-app-primary-dark); }
.qs-sidebar-upgrade .qs-btn:hover { background: #eaf1ff; }

.qs-dark-toggle {
    display: flex;
    align-items: center;
    gap: 10px;
    width: 100%;
    padding: 10px 12px;
    border: 1px solid var(--qs-app-border);
    background: var(--qs-app-card-soft);
    border-radius: 12px;
    color: var(--qs-app-text-soft);
    font-size: 0.86rem;
    font-weight: 600;
    cursor: pointer;
    transition: border-color 0.18s ease, background 0.18s ease;
}
.qs-dark-toggle:hover { border-color: var(--qs-app-primary-border); }
.qs-dark-icon { flex-shrink: 0; color: var(--qs-app-muted); }
.qs-dark-icon-moon { display: none; }
.qs-dark-label { flex: 1; text-align: left; }

.qs-switch {
    width: 36px;
    height: 20px;
    border-radius: 999px;
    background: var(--qs-app-border-strong);
    position: relative;
    transition: background 0.25s ease;
    flex-shrink: 0;
}
.qs-switch i {
    position: absolute;
    top: 2px;
    left: 2px;
    width: 16px;
    height: 16px;
    border-radius: 50%;
    background: #fff;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.25);
    transition: transform 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}
html[data-theme="dark"] .qs-switch { background: var(--qs-app-primary); }
html[data-theme="dark"] .qs-switch i { transform: translateX(16px); }
html[data-theme="dark"] .qs-dark-icon-moon { display: block; }
html[data-theme="dark"] .qs-dark-icon-sun { display: none; }

/* Sidebar overlay (mobile) */
.qs-sidebar-overlay {
    position: fixed;
    inset: 0;
    background: rgba(15, 23, 42, 0.5);
    backdrop-filter: blur(2px);
    z-index: 1150;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.25s ease, visibility 0.25s ease;
}
body.qs-sidebar-open .qs-sidebar-overlay { opacity: 1; visibility: visible; }

/* -------------------------------------------------------------------------
   App body + topbar
   ------------------------------------------------------------------------- */
.qs-app-body {
    margin-left: var(--qs-app-sidebar-w);
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

.qs-app-topbar {
    position: sticky;
    top: 0;
    z-index: 1100;
    height: var(--qs-app-topbar-h);
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
    padding: 0 28px;
    background: rgba(255, 255, 255, 0.86);
    backdrop-filter: blur(14px) saturate(160%);
    -webkit-backdrop-filter: blur(14px) saturate(160%);
    border-bottom: 1px solid var(--qs-app-border);
    transition: background 0.3s ease;
}
html[data-theme="dark"] .qs-app-topbar { background: rgba(16, 26, 46, 0.86); }

.qs-topbar-left { display: flex; align-items: center; gap: 14px; flex: 1; min-width: 0; }

.qs-icon-btn {
    position: relative;
    width: 40px;
    height: 40px;
    border-radius: 12px;
    border: 1px solid var(--qs-app-border);
    background: var(--qs-app-card);
    color: var(--qs-app-text-soft);
    display: grid;
    place-items: center;
    cursor: pointer;
    flex-shrink: 0;
    transition: border-color 0.18s ease, color 0.18s ease, transform 0.15s ease;
}
.qs-icon-btn:hover { border-color: var(--qs-app-primary-border); color: var(--qs-app-primary); }
.qs-icon-btn:active { transform: scale(0.94); }

.qs-has-dot::after {
    content: "";
    position: absolute;
    top: 9px;
    right: 10px;
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: #ef4444;
    border: 2px solid var(--qs-app-card);
    box-sizing: content-box;
}
.qs-has-dot-green::after { background: #10b981; }

.qs-sidebar-open { display: none; }

.qs-topbar-mobile-brand { display: none; align-items: center; gap: 8px; text-decoration: none; min-width: 0; overflow: hidden; white-space: nowrap; }
.qs-topbar-mobile-brand span { font-weight: 800; font-size: 1.1rem; color: var(--qs-app-text); letter-spacing: -0.02em; overflow: hidden; text-overflow: ellipsis; }

/* Topbar search */
.qs-topbar-search {
    position: relative;
    flex: 1;
    max-width: 560px;
    display: flex;
    align-items: center;
}
.qs-search-icon {
    position: absolute;
    left: 14px;
    color: var(--qs-app-muted);
    pointer-events: none;
}
.qs-global-search {
    width: 100%;
    height: 44px;
    padding: 0 58px 0 42px;
    border-radius: 12px;
    border: 1px solid var(--qs-app-border);
    background: var(--qs-app-card-soft);
    color: var(--qs-app-text);
    font-size: 0.88rem;
    transition: border-color 0.18s ease, box-shadow 0.18s ease, background 0.18s ease;
}
.qs-global-search::placeholder { color: var(--qs-app-muted); }
.qs-global-search:focus {
    outline: none;
    border-color: var(--qs-app-primary);
    background: var(--qs-app-card);
    box-shadow: 0 0 0 4px var(--qs-app-primary-soft);
}
.qs-search-kbd {
    position: absolute;
    right: 12px;
    width: 24px;
    height: 24px;
    border-radius: 6px;
    border: 1px solid var(--qs-app-border-strong);
    background: var(--qs-app-card);
    color: var(--qs-app-muted);
    font-size: 0.72rem;
    font-weight: 700;
    display: grid;
    place-items: center;
    pointer-events: none;
}

/* Search panel dropdown */
.qs-search-panel {
    position: absolute;
    top: calc(100% + 10px);
    left: 0;
    right: 0;
    background: var(--qs-app-card);
    border: 1px solid var(--qs-app-border);
    border-radius: 16px;
    box-shadow: var(--qs-app-shadow-lg);
    opacity: 0;
    visibility: hidden;
    transform: translateY(8px);
    transition: opacity 0.2s ease, transform 0.2s ease, visibility 0.2s ease;
    overflow: hidden;
    z-index: 1300;
}
.qs-topbar-search.qs-search-open .qs-search-panel { opacity: 1; visibility: visible; transform: translateY(0); }
.qs-search-panel-inner { padding: 14px; display: flex; flex-direction: column; gap: 14px; max-height: 420px; overflow-y: auto; }

.qs-search-group-title {
    display: block;
    font-size: 0.68rem;
    font-weight: 800;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--qs-app-faint);
    margin-bottom: 8px;
}
.qs-search-group { display: flex; flex-direction: column; gap: 8px; }
.qs-search-group:not(:first-child) { border-top: 1px solid var(--qs-app-border); padding-top: 14px; }

.qs-search-chip {
    display: inline-flex;
    align-items: center;
    width: fit-content;
    gap: 6px;
    padding: 6px 12px;
    border-radius: 999px;
    border: 1px solid var(--qs-app-border);
    background: var(--qs-app-card-soft);
    color: var(--qs-app-text-soft);
    font-size: 0.78rem;
    font-weight: 600;
    cursor: pointer;
    transition: border-color 0.18s ease, color 0.18s ease, background 0.18s ease;
}
.qs-search-chip:hover { border-color: var(--qs-app-primary); color: var(--qs-app-primary); }
.qs-chip-fire { color: #b45309; }
html[data-theme="dark"] .qs-chip-fire { color: #fbbf24; }

.qs-search-results { display: flex; flex-direction: column; gap: 4px; }
.qs-search-result {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 9px 10px;
    border-radius: 10px;
    text-decoration: none;
    color: var(--qs-app-text-soft);
    transition: background 0.15s ease;
}
.qs-search-result:hover { background: var(--qs-app-primary-soft); color: var(--qs-app-primary); }
.qs-search-result svg { flex-shrink: 0; color: var(--qs-app-muted); }
.qs-search-result small { color: var(--qs-app-muted); font-size: 0.72rem; display: block; }
.qs-search-nores { padding: 10px; font-size: 0.82rem; color: var(--qs-app-muted); }

/* Topbar right */
.qs-topbar-right { display: flex; align-items: center; gap: 10px; flex-shrink: 0; }

.qs-search-open-mobile { display: none; }

.qs-topbar-profile { position: relative; }
.qs-profile-btn {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 5px 8px 5px 5px;
    border: 1px solid transparent;
    border-radius: 999px;
    background: transparent;
    cursor: pointer;
    transition: border-color 0.18s ease, background 0.18s ease;
}
.qs-profile-btn:hover { border-color: var(--qs-app-border); background: var(--qs-app-card-soft); }
.qs-profile-avatar { position: relative; display: inline-flex; }
.qs-profile-avatar img,
.qs-profile-avatar svg { width: 34px; height: 34px; border-radius: 50%; display: block; }
.qs-profile-online {
    position: absolute;
    right: -1px;
    bottom: 0;
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: #22c55e;
    border: 2px solid var(--qs-app-card);
}
.qs-profile-meta { display: flex; flex-direction: column; text-align: left; line-height: 1.2; }
.qs-profile-meta strong { font-size: 0.82rem; color: var(--qs-app-text); font-weight: 700; }
.qs-profile-meta small { font-size: 0.68rem; color: var(--qs-app-muted); }
.qs-profile-chev { color: var(--qs-app-muted); }

.qs-profile-dropdown {
    position: absolute;
    right: 0;
    top: calc(100% + 12px);
    width: 224px;
    background: var(--qs-app-card);
    border: 1px solid var(--qs-app-border);
    border-radius: 16px;
    box-shadow: var(--qs-app-shadow-lg);
    padding: 8px;
    opacity: 0;
    visibility: hidden;
    transform: translateY(8px);
    transition: opacity 0.2s ease, transform 0.2s ease, visibility 0.2s ease;
    z-index: 1300;
}
.qs-topbar-profile.qs-profile-open .qs-profile-dropdown { opacity: 1; visibility: visible; transform: translateY(0); }
.qs-profile-dropdown a {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 9px 10px;
    border-radius: 10px;
    color: var(--qs-app-text-soft);
    font-size: 0.84rem;
    font-weight: 500;
    text-decoration: none;
    transition: background 0.15s ease, color 0.15s ease;
}
.qs-profile-dropdown a:hover { background: var(--qs-app-primary-soft); color: var(--qs-app-primary); }
.qs-profile-dropdown a svg { color: var(--qs-app-muted); }
.qs-profile-dropdown-divider { height: 1px; background: var(--qs-app-border); margin: 6px 0; }

/* Topbar action dropdowns (notifications, messages) */
.qs-topbar-action { position: relative; }
.qs-topbar-dropdown {
    position: absolute;
    right: 0;
    top: calc(100% + 12px);
    width: 300px;
    max-width: calc(100vw - 32px);
    background: var(--qs-app-card);
    border: 1px solid var(--qs-app-border);
    border-radius: 16px;
    box-shadow: var(--qs-app-shadow-lg);
    overflow: hidden;
    opacity: 0;
    visibility: hidden;
    transform: translateY(8px);
    transition: opacity 0.2s ease, transform 0.2s ease, visibility 0.2s ease;
    z-index: 1300;
}
.qs-topbar-action.qs-action-open .qs-topbar-dropdown { opacity: 1; visibility: visible; transform: translateY(0); }
.qs-dropdown-header {
    padding: 12px 16px;
    border-bottom: 1px solid var(--qs-app-border);
    font-size: 0.8rem;
    font-weight: 800;
    letter-spacing: 0.02em;
    color: var(--qs-app-text);
}
.qs-dropdown-empty {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 6px;
    padding: 26px 20px;
    text-align: center;
    color: var(--qs-app-muted);
}
.qs-dropdown-empty svg { color: var(--qs-app-primary); opacity: 0.7; }
.qs-dropdown-empty strong { font-size: 0.9rem; color: var(--qs-app-text); }
.qs-dropdown-empty span { font-size: 0.78rem; line-height: 1.5; }

.qs-topbar-signup { display: none; }

/* -------------------------------------------------------------------------
   App content grid — single full-width column (the right sidebar was
   removed so the main content spans all available space).
   ------------------------------------------------------------------------- */
.qs-app-content {
    flex: 1;
    width: 100%;
    max-width: 1560px;
    margin: 0 auto;
    padding: 26px 30px 56px;
    display: grid;
    grid-template-columns: minmax(0, 1fr);
    gap: 26px;
    align-items: start;
}

.qs-main-content { min-width: 0; display: flex; flex-direction: column; gap: 28px; }

/* -------------------------------------------------------------------------
   Exam Results / Performance Report — full-width inside the app shell
   (left menu sidebar only, no right widget sidebar).
   ------------------------------------------------------------------------- */
body.qs-app-results .qs-results-layout {
    width: 100%;
    max-width: 900px;
}
body.qs-app-results .qs-results-main { min-width: 0; display: flex; flex-direction: column; gap: 20px; }
body.qs-app-results .qs-results-main .questudy-results-wrap,
body.qs-app-results .qs-results-main .questudy-results-list,
body.qs-app-results .qs-results-main .questudy-review-wrap { width: 100%; }

/* -------------------------------------------------------------------------
   Shared widgets/panels
   ------------------------------------------------------------------------- */
.qs-section-head {
    display: flex;
    align-items: flex-end;
    justify-content: space-between;
    gap: 16px;
    margin-bottom: 16px;
}
.qs-section-kicker {
    display: block;
    font-size: 0.7rem;
    font-weight: 800;
    letter-spacing: 0.09em;
    text-transform: uppercase;
    color: var(--qs-app-primary);
    margin-bottom: 4px;
}
.qs-kicker-ai { color: #9333ea; }
html[data-theme="dark"] .qs-kicker-ai { color: #a78bfa; }
.qs-section-title { margin: 0; font-size: 1.3rem; font-weight: 800; letter-spacing: -0.02em; }
.qs-section-more {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-size: 0.82rem;
    font-weight: 700;
    color: var(--qs-app-primary);
    text-decoration: none;
    white-space: nowrap;
    transition: gap 0.18s ease;
}
.qs-section-more:hover { gap: 10px; }

.qs-panel {
    background: var(--qs-app-card);
    border: 1px solid var(--qs-app-border);
    border-radius: var(--qs-app-radius-lg);
    box-shadow: var(--qs-app-shadow);
    padding: 20px;
    transition: box-shadow 0.25s ease, border-color 0.25s ease;
}
.qs-panel:hover { box-shadow: var(--qs-app-shadow-md); }

.qs-panel-head {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    gap: 12px;
    margin-bottom: 16px;
}
.qs-panel-title-wrap { display: flex; align-items: center; gap: 12px; min-width: 0; }
.qs-panel-ico {
    width: 42px;
    height: 42px;
    border-radius: 12px;
    display: grid;
    place-items: center;
    flex-shrink: 0;
}
.qs-ico-blue { background: var(--qs-app-primary-soft); color: var(--qs-app-primary); }
.qs-ico-orange { background: rgba(249, 115, 22, 0.12); color: #ea580c; }
.qs-ico-green { background: rgba(16, 185, 129, 0.12); color: #059669; }
.qs-panel-title { margin: 0; font-size: 1rem; font-weight: 800; }
.qs-panel-sub { margin: 2px 0 0; font-size: 0.74rem; color: var(--qs-app-muted); }
.qs-panel-more { font-size: 0.78rem; font-weight: 700; color: var(--qs-app-muted); text-decoration: none; white-space: nowrap; }
.qs-panel-more:hover { color: var(--qs-app-primary); }

/* Progress bar primitive */
.qs-progress {
    height: 8px;
    border-radius: 999px;
    background: var(--qs-app-border);
    overflow: hidden;
    position: relative;
}
.qs-progress i {
    display: block;
    height: 100%;
    border-radius: 999px;
    background: var(--qs-gradient-primary);
    transition: width 0.8s cubic-bezier(0.4, 0, 0.2, 1);
}

/* Buttons (app-shell scoped) */
body.qs-app-shell .qs-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    border: none;
    border-radius: 12px;
    font-weight: 700;
    font-size: 0.88rem;
    line-height: 1;
    padding: 12px 20px;
    cursor: pointer;
    text-decoration: none;
    transition: transform 0.15s ease, box-shadow 0.2s ease, background 0.2s ease, color 0.2s ease, border-color 0.2s ease;
}
body.qs-app-shell .qs-btn:hover { transform: translateY(-1px); }
body.qs-app-shell .qs-btn:active { transform: translateY(0) scale(0.98); }
body.qs-app-shell .qs-btn:focus-visible { outline: 2px solid var(--qs-app-primary); outline-offset: 2px; }

body.qs-app-shell .qs-btn-primary {
    background: var(--qs-gradient-primary);
    color: #fff;
    box-shadow: 0 6px 16px -6px rgba(37, 99, 235, 0.5);
}
body.qs-app-shell .qs-btn-primary:hover { box-shadow: 0 10px 22px -8px rgba(37, 99, 235, 0.6); }
body.qs-app-shell .qs-btn-outline {
    background: var(--qs-app-card);
    color: var(--qs-app-primary);
    border: 1px solid var(--qs-app-primary-border);
}
body.qs-app-shell .qs-btn-outline:hover { background: var(--qs-app-primary-soft); border-color: var(--qs-app-primary); }
body.qs-app-shell .qs-btn-soft {
    background: var(--qs-app-primary-soft);
    color: var(--qs-app-primary);
    border: 1px solid transparent;
}
body.qs-app-shell .qs-btn-soft:hover { border-color: var(--qs-app-primary-border); }
body.qs-app-shell .qs-btn-white { background: #fff; color: var(--qs-app-primary-dark); box-shadow: 0 8px 20px -8px rgba(2, 6, 23, 0.4); }
body.qs-app-shell .qs-btn-ghost-white { background: transparent; color: #fff; border: 1px solid rgba(255, 255, 255, 0.4); }
body.qs-app-shell .qs-btn-ghost-white:hover { background: rgba(255, 255, 255, 0.12); }
body.qs-app-shell .qs-btn-lg { padding: 15px 26px; font-size: 0.95rem; border-radius: 14px; }
body.qs-app-shell .qs-btn-xl { padding: 17px 34px; font-size: 1rem; border-radius: 14px; }
body.qs-app-shell .qs-btn-sm { padding: 9px 15px; font-size: 0.8rem; border-radius: 10px; }
body.qs-app-shell .qs-btn-full { width: 100%; }
body.qs-app-shell .qs-btn-glow { animation: qs-btn-glow 3s ease-in-out infinite; }
@keyframes qs-btn-glow {
    0%, 100% { box-shadow: 0 6px 16px -6px rgba(37, 99, 235, 0.5); }
    50% { box-shadow: 0 6px 26px 0 rgba(37, 99, 235, 0.65); }
}

/* -------------------------------------------------------------------------
   Hero
   ------------------------------------------------------------------------- */
.qs-home-hero {
    position: relative;
    overflow: hidden;
    background: var(--qs-app-card);
    border: 1px solid var(--qs-app-border);
    border-radius: 24px;
    box-shadow: var(--qs-app-shadow);
    padding: 40px 44px;
}
html[data-theme="dark"] .qs-home-hero { background: linear-gradient(160deg, #12203c 0%, #101a2e 60%); }

.qs-hero-bg-blob { position: absolute; border-radius: 50%; filter: blur(70px); opacity: 0.5; pointer-events: none; }
.qs-blob-a { width: 320px; height: 320px; background: radial-gradient(circle, rgba(37, 99, 235, 0.28), transparent 70%); top: -140px; left: -100px; }
.qs-blob-b { width: 300px; height: 300px; background: radial-gradient(circle, rgba(139, 92, 246, 0.2), transparent 70%); bottom: -140px; right: -80px; }
.qs-hero-dots {
    position: absolute;
    inset: 0;
    background-image: radial-gradient(rgba(37, 99, 235, 0.14) 1.4px, transparent 1.4px);
    background-size: 26px 26px;
    mask-image: radial-gradient(ellipse 70% 60% at 70% 30%, #000 20%, transparent 70%);
    -webkit-mask-image: radial-gradient(ellipse 70% 60% at 70% 30%, #000 20%, transparent 70%);
    pointer-events: none;
}

.qs-hero-grid {
    position: relative;
    display: grid;
    grid-template-columns: minmax(0, 1.08fr) minmax(0, 0.92fr);
    gap: 36px;
    align-items: center;
}

.qs-hero-pill {
    display: inline-flex;
    align-items: center;
    gap: 7px;
    padding: 7px 14px;
    border-radius: 999px;
    background: var(--qs-app-primary-soft);
    border: 1px solid var(--qs-app-primary-border);
    color: var(--qs-app-primary);
    font-size: 0.76rem;
    font-weight: 700;
    margin-bottom: 18px;
}

.qs-hero-title {
    margin: 0 0 14px;
    font-size: clamp(1.9rem, 3.4vw, 2.9rem);
    font-weight: 800;
    line-height: 1.12;
    letter-spacing: -0.03em;
}
.qs-hero-title span {
    background: var(--qs-gradient-primary);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    color: transparent;
}
.qs-hero-sub { margin: 0 0 22px; max-width: 540px; font-size: 0.98rem; line-height: 1.65; color: var(--qs-app-text-soft); }

.qs-hero-search {
    display: flex;
    align-items: center;
    gap: 10px;
    max-width: 560px;
    background: var(--qs-app-card-soft);
    border: 1.5px solid var(--qs-app-border-strong);
    border-radius: 16px;
    padding: 7px 7px 7px 18px;
    margin-bottom: 20px;
    transition: border-color 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
}
.qs-hero-search:focus-within {
    border-color: var(--qs-app-primary);
    box-shadow: 0 0 0 4px var(--qs-app-primary-soft);
    background: var(--qs-app-card);
}
.qs-hero-search svg { color: var(--qs-app-muted); flex-shrink: 0; }
.qs-hero-search input {
    flex: 1;
    min-width: 0;
    border: none;
    background: transparent;
    color: var(--qs-app-text);
    font-size: 0.9rem;
    padding: 10px 0;
}
.qs-hero-search input:focus { outline: none; }
.qs-hero-search input::placeholder { color: var(--qs-app-muted); }
.qs-hero-search .qs-btn { padding: 12px 22px; }

/* Hero search results + Charles answer panel */
.qs-hero-search-results {
    max-width: 560px;
    margin-bottom: 20px;
    background: var(--qs-app-card);
    border: 1.5px solid var(--qs-app-border-strong);
    border-radius: 16px;
    padding: 14px;
    box-shadow: var(--qs-app-shadow-lg);
    animation: qs-hsr-fade 0.18s ease;
}
@keyframes qs-hsr-fade { from { opacity: 0; transform: translateY(-4px); } to { opacity: 1; transform: none; } }

.qs-hsr-head { display: flex; align-items: center; justify-content: space-between; margin-bottom: 10px; }
.qs-hsr-title { font-size: 0.72rem; font-weight: 800; color: var(--qs-app-muted); text-transform: uppercase; letter-spacing: 0.05em; }

.qs-hsr-list { list-style: none; margin: 0; padding: 0; display: flex; flex-direction: column; gap: 8px; }
.qs-hsr-item { border: 1px solid var(--qs-app-border); border-radius: 12px; overflow: hidden; transition: border-color 0.15s ease, background 0.15s ease; }
.qs-hsr-item:hover { border-color: var(--qs-app-primary-border); background: var(--qs-app-primary-soft); }
.qs-hsr-link { display: flex; flex-direction: column; gap: 3px; padding: 10px 12px; text-decoration: none; }
.qs-hsr-item-title { font-size: 0.92rem; font-weight: 700; color: var(--qs-app-text); }
.qs-hsr-item-type { align-self: flex-start; font-size: 0.68rem; font-weight: 700; text-transform: uppercase; letter-spacing: 0.03em; color: var(--qs-app-primary); background: var(--qs-app-primary-soft); border: 1px solid var(--qs-app-primary-border); padding: 2px 8px; border-radius: 999px; }
.qs-hsr-item-excerpt { font-size: 0.8rem; line-height: 1.5; color: var(--qs-app-text-soft); display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden; }
.qs-hsr-foot { margin-top: 12px; text-align: right; }
.qs-hsr-see-all { font-size: 0.85rem; font-weight: 700; color: var(--qs-app-primary); text-decoration: none; }
.qs-hsr-see-all:hover { text-decoration: underline; }

.qs-hsr-loading { display: flex; align-items: center; gap: 10px; color: var(--qs-app-text-soft); font-size: 0.9rem; padding: 6px 2px; }
.qs-hsr-spinner { width: 18px; height: 18px; border-radius: 50%; border: 2.5px solid var(--qs-app-border-strong); border-top-color: var(--qs-app-primary); animation: qs-hsr-spin 0.8s linear infinite; flex-shrink: 0; }
@keyframes qs-hsr-spin { to { transform: rotate(360deg); } }
.qs-hsr-error { color: #dc2626; font-size: 0.9rem; padding: 4px 2px; }

.qs-hsr-charles { border: 1.5px solid var(--qs-app-primary-border); border-radius: 14px; padding: 14px; background: var(--qs-app-card-soft); }
.qs-hsr-charles-head { display: flex; align-items: center; gap: 10px; margin-bottom: 10px; }
.qs-hsr-charles-avatar { display: flex; align-items: center; justify-content: center; width: 36px; height: 36px; border-radius: 50%; background: var(--qs-gradient-primary); color: #fff; flex-shrink: 0; }
.qs-hsr-charles-name { font-weight: 800; font-size: 0.95rem; color: var(--qs-app-text); }
.qs-hsr-charles-badge { margin-left: auto; font-size: 0.66rem; font-weight: 800; text-transform: uppercase; letter-spacing: 0.04em; color: var(--qs-app-primary); background: var(--qs-app-primary-soft); border: 1px solid var(--qs-app-primary-border); padding: 3px 9px; border-radius: 999px; }
.qs-hsr-charles-body { font-size: 0.9rem; line-height: 1.65; color: var(--qs-app-text); }
.qs-hsr-charles-body p { margin: 0 0 10px; }
.qs-hsr-charles-body p:last-child { margin-bottom: 0; }
.qs-hsr-charles-body ul { margin: 0 0 10px; padding-left: 20px; }
.qs-hsr-charles-body h3, .qs-hsr-charles-body h4 { margin: 12px 0 6px; }
.qs-hsr-charles-body pre { background: var(--qs-app-card); border: 1px solid var(--qs-app-border); border-radius: 10px; padding: 10px; overflow: auto; font-size: 0.82rem; }
.qs-hsr-charles-body code { background: var(--qs-app-card); border: 1px solid var(--qs-app-border); padding: 1px 5px; border-radius: 6px; font-size: 0.82rem; }
.qs-hsr-charles-foot { display: flex; align-items: center; justify-content: space-between; gap: 10px; margin-top: 12px; padding-top: 10px; border-top: 1px dashed var(--qs-app-border); flex-wrap: wrap; }
.qs-hsr-charles-query { font-size: 0.78rem; font-style: italic; color: var(--qs-app-muted); }
.qs-hsr-try { font-size: 0.78rem; color: var(--qs-app-text-soft); }

.qs-hero-actions { display: flex; align-items: center; gap: 12px; flex-wrap: wrap; }

/* Hero visual */
.qs-hero-visual { position: relative; }
.qs-hero-illustration { position: relative; max-width: 470px; margin: 0 auto; }
.qs-student-svg { width: 100%; height: auto; }
.qs-student-photo {
    width: 100%;
    height: auto;
    display: block;
    aspect-ratio: 460 / 420;
    object-fit: cover;
    object-position: center 30%;
    border-radius: 24px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.15);
}

.qs-hero-float {
    position: absolute;
    display: flex;
    align-items: center;
    gap: 9px;
    background: var(--qs-app-card);
    border: 1px solid var(--qs-app-border);
    border-radius: 14px;
    box-shadow: var(--qs-app-shadow-md);
    padding: 10px 14px 10px 10px;
    animation: qs-float 5.5s ease-in-out infinite;
}
.qs-hero-float strong { display: block; font-size: 0.78rem; color: var(--qs-app-text); line-height: 1.15; }
.qs-hero-float small { display: block; font-size: 0.66rem; color: var(--qs-app-muted); }
.qs-float-ico { width: 34px; height: 34px; border-radius: 10px; display: grid; place-items: center; flex-shrink: 0; }
.qs-ico-blue { background: var(--qs-app-primary-soft); color: var(--qs-app-primary); }
.qs-ico-amber { background: rgba(245, 158, 11, 0.14); color: #d97706; }
.qs-ico-green { background: rgba(16, 185, 129, 0.14); color: #059669; }

.qs-float-a { top: 4%; left: -4%; animation-delay: 0s; }
.qs-float-b { bottom: 16%; right: -2%; animation-delay: 1.4s; }
.qs-float-c { bottom: -4%; left: 10%; animation-delay: 2.6s; }

@keyframes qs-float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-10px); }
}

/* -------------------------------------------------------------------------
   Subject chips
   ------------------------------------------------------------------------- */
.qs-subject-chips {
    display: flex;
    gap: 10px;
    overflow-x: auto;
    padding: 4px 2px 10px;
    scrollbar-width: thin;
    scrollbar-color: var(--qs-app-border-strong) transparent;
    scroll-snap-type: x proximity;
}
.qs-subject-chip {
    display: inline-flex;
    align-items: center;
    gap: 9px;
    padding: 9px 16px 9px 9px;
    border-radius: 999px;
    background: var(--qs-app-card);
    border: 1px solid var(--qs-app-border);
    color: var(--qs-app-text-soft);
    font-size: 0.82rem;
    font-weight: 600;
    text-decoration: none;
    white-space: nowrap;
    scroll-snap-align: start;
    transition: border-color 0.18s ease, box-shadow 0.18s ease, transform 0.18s ease, color 0.18s ease;
}
.qs-subject-chip:hover { border-color: var(--chip-color); color: var(--chip-color); box-shadow: var(--qs-app-shadow-md); transform: translateY(-2px); }
.qs-subject-chip-ico {
    width: 30px;
    height: 30px;
    border-radius: 50%;
    display: grid;
    place-items: center;
    background: var(--chip-color);
    color: #fff;
    font-size: 0.72rem;
    font-weight: 800;
    flex-shrink: 0;
}

/* -------------------------------------------------------------------------
   Feature grid — 8 cards
   ------------------------------------------------------------------------- */
.qs-feature-grid {
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 18px;
}

.qs-feature-card {
    position: relative;
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    background: var(--qs-app-card);
    border: 1px solid var(--qs-app-border);
    border-radius: var(--qs-app-radius);
    box-shadow: var(--qs-app-shadow);
    padding: 22px 20px 18px;
    text-decoration: none;
    overflow: hidden;
    transition: transform 0.25s ease, box-shadow 0.25s ease, border-color 0.25s ease;
}
.qs-feature-card::before {
    content: "";
    position: absolute;
    inset: 0 0 auto 0;
    height: 4px;
    background: linear-gradient(90deg, var(--fc-color), transparent);
    opacity: 0.85;
}
.qs-feature-card::after {
    content: "";
    position: absolute;
    top: 0;
    right: 0;
    width: 120px;
    height: 120px;
    border-radius: 50%;
    background: radial-gradient(circle, var(--fc-color) 0%, transparent 70%);
    opacity: 0.08;
    transform: translate(40px, -60px);
    transition: opacity 0.3s ease, transform 0.3s ease;
}
.qs-feature-card:hover { transform: translateY(-5px); box-shadow: var(--qs-app-shadow-lg); border-color: var(--fc-color); }
.qs-feature-card:hover::after { opacity: 0.16; transform: translate(30px, -50px); }

.qs-fc-icon {
    width: 52px;
    height: 52px;
    border-radius: 14px;
    display: grid;
    place-items: center;
    background: rgba(37, 99, 235, 0.12);
    background: color-mix(in srgb, var(--fc-color) 12%, transparent);
    color: var(--fc-color);
    margin-bottom: 16px;
    transition: background 0.25s ease, color 0.25s ease, transform 0.25s ease;
}
.qs-feature-card:hover .qs-fc-icon { background: var(--fc-color); color: #fff; transform: rotate(-6deg) scale(1.06); }

.qs-fc-title { margin: 0 0 6px; font-size: 1rem; font-weight: 800; color: var(--qs-app-text); line-height: 1.3; }
.qs-fc-desc { margin: 0 0 14px; font-size: 0.8rem; line-height: 1.55; color: var(--qs-app-muted); flex: 1; }
.qs-fc-link {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-size: 0.8rem;
    font-weight: 700;
    color: var(--fc-color);
    transition: gap 0.2s ease;
}
.qs-fc-link svg { transition: transform 0.2s ease; }
.qs-feature-card:hover .qs-fc-link { gap: 10px; }

/* -------------------------------------------------------------------------
   AI tools row
   ------------------------------------------------------------------------- */
.qs-aitools-row {
    display: flex;
    gap: 16px;
    overflow-x: auto;
    padding: 4px 2px 12px;
    scroll-snap-type: x proximity;
    scrollbar-width: thin;
    scrollbar-color: var(--qs-app-border-strong) transparent;
}
.qs-aitool-card {
    flex: 0 0 auto;
    width: 240px;
    display: flex;
    align-items: center;
    gap: 12px;
    background: var(--qs-app-card);
    border: 1px solid var(--qs-app-border);
    border-radius: 16px;
    box-shadow: var(--qs-app-shadow);
    padding: 16px 14px;
    text-decoration: none;
    scroll-snap-align: start;
    transition: transform 0.2s ease, box-shadow 0.2s ease, border-color 0.2s ease;
}
.qs-aitool-card:hover { transform: translateY(-4px); box-shadow: var(--qs-app-shadow-lg); border-color: var(--ai-color); }

.qs-aitool-icon {
    width: 44px;
    height: 44px;
    border-radius: 12px;
    display: grid;
    place-items: center;
    flex-shrink: 0;
    background: rgba(37, 99, 235, 0.12);
    background: color-mix(in srgb, var(--ai-color) 12%, transparent);
    color: var(--ai-color);
    transition: background 0.2s ease, color 0.2s ease;
}
.qs-aitool-card:hover .qs-aitool-icon { background: var(--ai-color); color: #fff; }

.qs-aitool-body { flex: 1; min-width: 0; display: flex; flex-direction: column; }
.qs-aitool-name { font-size: 0.88rem; font-weight: 800; color: var(--qs-app-text); line-height: 1.25; }
.qs-aitool-desc { font-size: 0.7rem; color: var(--qs-app-muted); line-height: 1.35; margin-top: 2px; display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden; }
.qs-aitool-arrow { flex-shrink: 0; color: var(--qs-app-faint); transition: transform 0.2s ease, color 0.2s ease; }
.qs-aitool-card:hover .qs-aitool-arrow { transform: translateX(3px); color: var(--ai-color); }

/* -------------------------------------------------------------------------
   Content row — 3 columns
   ------------------------------------------------------------------------- */
.qs-content-row {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 18px;
    align-items: start;
}

/* Arena */
.qs-arena-daily {
    background: linear-gradient(150deg, rgba(249, 115, 22, 0.09), rgba(251, 146, 60, 0.04));
    border: 1px solid rgba(249, 115, 22, 0.25);
    border-radius: 16px;
    padding: 16px;
    margin-bottom: 14px;
    text-align: center;
}
.qs-arena-tag {
    display: inline-flex;
    align-items: center;
    gap: 5px;
    font-size: 0.7rem;
    font-weight: 800;
    letter-spacing: 0.05em;
    text-transform: uppercase;
    color: #c2410c;
    background: rgba(255, 255, 255, 0.6);
    border: 1px solid rgba(249, 115, 22, 0.3);
    padding: 4px 10px;
    border-radius: 999px;
    margin-bottom: 8px;
}
html[data-theme="dark"] .qs-arena-tag { background: rgba(15, 23, 42, 0.4); color: #fb923c; }
.qs-arena-daily > strong { display: block; font-size: 0.95rem; color: var(--qs-app-text); margin-bottom: 2px; }
.qs-arena-ends { font-size: 0.72rem; color: var(--qs-app-muted); }

.qs-countdown { display: flex; align-items: center; justify-content: center; gap: 8px; margin: 12px 0 14px; }
.qs-cd-box {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    min-width: 56px;
    height: 62px;
    border-radius: 12px;
    background: var(--qs-app-card);
    border: 1px solid var(--qs-app-border);
    box-shadow: var(--qs-app-shadow);
}
.qs-cd-box b { font-size: 1.35rem; font-weight: 800; color: var(--qs-app-text); line-height: 1; }
.qs-cd-box small { font-size: 0.62rem; font-weight: 700; color: var(--qs-app-muted); margin-top: 3px; }
.qs-cd-sep { font-size: 1.2rem; font-weight: 800; color: var(--qs-app-faint); }
.qs-arena-xp {
    margin-left: 4px;
    font-size: 0.7rem;
    font-weight: 800;
    color: #b45309;
    background: rgba(245, 158, 11, 0.14);
    border: 1px solid rgba(245, 158, 11, 0.3);
    border-radius: 999px;
    padding: 5px 10px;
}
html[data-theme="dark"] .qs-arena-xp { color: #fbbf24; }

.qs-arena-list { list-style: none; margin: 0; padding: 0; display: flex; flex-direction: column; gap: 4px; }
.qs-arena-list li {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 10px 12px;
    border-radius: 12px;
    transition: background 0.15s ease;
}
.qs-arena-list li:hover { background: var(--qs-app-card-soft); }
.qs-arena-list li > div { flex: 1; min-width: 0; }
.qs-arena-list strong { display: block; font-size: 0.84rem; color: var(--qs-app-text); }
.qs-arena-list small { display: block; font-size: 0.7rem; color: var(--qs-app-muted); }
.qs-al-ico { width: 34px; height: 34px; border-radius: 10px; display: grid; place-items: center; flex-shrink: 0; }
.qs-al-weekly { background: rgba(99, 102, 241, 0.12); color: #4f46e5; }
.qs-al-school { background: rgba(16, 185, 129, 0.12); color: #059669; }
.qs-al-national { background: rgba(59, 130, 246, 0.12); color: #2563eb; }
.qs-al-prize { background: rgba(245, 158, 11, 0.14); color: #d97706; }
.qs-al-value { font-size: 0.8rem; font-weight: 800; color: var(--qs-app-text); }

/* Daily challenge form, error and today's leaderboard */
.qs-arena-form { margin: 0; }
.qs-arena-form .qs-btn { width: 100%; }
.qs-arena-done {
    display: flex;
    align-items: center;
    gap: 8px;
    margin: 0;
    font-size: 0.8rem;
    font-weight: 600;
    line-height: 1.45;
    color: var(--qs-app-text);
    background: rgba(16, 185, 129, 0.1);
    border: 1px solid rgba(16, 185, 129, 0.25);
    border-radius: 10px;
    padding: 10px 12px;
}
.qs-arena-done-ico { font-size: 1rem; flex-shrink: 0; }
.qs-arena-done a {
    color: #059669;
    font-weight: 700;
    text-decoration: none;
    white-space: nowrap;
}
.qs-arena-done a:hover { text-decoration: underline; }
.qs-arena-err {
    margin: 10px 0 0;
    font-size: 0.75rem;
    font-weight: 600;
    color: #b91c1c;
    background: rgba(239, 68, 68, 0.1);
    border: 1px solid rgba(239, 68, 68, 0.25);
    border-radius: 10px;
    padding: 8px 10px;
}
.qs-arena-today {
    list-style: none;
    margin: 14px 0 0;
    padding: 0;
    border-top: 1px dashed var(--qs-app-border);
    display: flex;
    flex-direction: column;
    gap: 4px;
}
.qs-at-head {
    font-size: 0.68rem;
    font-weight: 800;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--qs-app-muted);
    padding: 10px 2px 2px;
}
.qs-arena-today li:not(.qs-at-head) {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 0.78rem;
    padding: 6px 8px;
    border-radius: 10px;
    text-align: left;
}
.qs-at-me { background: rgba(249, 115, 22, 0.1); }
.qs-at-rank { font-weight: 800; color: #c2410c; width: 26px; flex-shrink: 0; }
.qs-at-name { flex: 1; min-width: 0; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; color: var(--qs-app-text); font-weight: 600; }
.qs-at-pct { font-weight: 800; color: var(--qs-app-text); }
.qs-at-empty { font-size: 0.75rem; color: var(--qs-app-muted); padding: 6px 8px; }
html[data-theme="dark"] .qs-at-rank { color: #fb923c; }
.qs-al-prize-val { color: #b45309; }
html[data-theme="dark"] .qs-al-prize-val { color: #fbbf24; }

/* Continue learning */
.qs-continue-list { display: flex; flex-direction: column; gap: 16px; margin-bottom: 18px; }
.qs-continue-item { display: flex; align-items: center; gap: 12px; }
.qs-continue-avatar {
    width: 44px;
    height: 44px;
    border-radius: 12px;
    display: grid;
    place-items: center;
    background: rgba(37, 99, 235, 0.14);
    background: color-mix(in srgb, var(--c-color) 14%, transparent);
    color: var(--c-color);
    font-size: 0.95rem;
    font-weight: 800;
    flex-shrink: 0;
}
.qs-continue-main { flex: 1; min-width: 0; }
.qs-continue-top { display: flex; justify-content: space-between; align-items: center; margin-bottom: 7px; gap: 8px; }
.qs-continue-top strong { font-size: 0.86rem; color: var(--qs-app-text); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.qs-continue-top span { font-size: 0.74rem; font-weight: 800; color: var(--qs-app-primary); }
.qs-continue-meta { display: block; font-size: 0.7rem; color: var(--qs-app-muted); margin-top: 6px; }

.qs-learning-stats {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 10px;
    padding-top: 16px;
    border-top: 1px solid var(--qs-app-border);
}
.qs-learning-stats div { text-align: center; }
.qs-learning-stats strong { display: block; font-size: 1.05rem; font-weight: 800; color: var(--qs-app-text); }
.qs-learning-stats strong span { font-size: 0.72rem; color: var(--qs-app-muted); }
.qs-learning-stats small { font-size: 0.66rem; color: var(--qs-app-muted); }

/* Live classes */
.qs-live-list { display: flex; flex-direction: column; gap: 6px; }
.qs-live-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px;
    border-radius: 14px;
    transition: background 0.15s ease;
}
.qs-live-item:hover { background: var(--qs-app-card-soft); }
.qs-live-date {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    width: 48px;
    height: 52px;
    border-radius: 12px;
    background: var(--qs-app-primary-soft);
    border: 1px solid var(--qs-app-primary-border);
    flex-shrink: 0;
}
.qs-live-date strong { font-size: 0.68rem; font-weight: 800; letter-spacing: 0.04em; color: var(--qs-app-primary); text-transform: uppercase; }
.qs-live-date small { font-size: 1.05rem; font-weight: 800; color: var(--qs-app-primary); line-height: 1.1; }
.qs-live-main { flex: 1; min-width: 0; }
.qs-live-topic { display: block; font-size: 0.84rem; color: var(--qs-app-text); line-height: 1.3; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.qs-live-tutor { display: inline-flex; align-items: center; gap: 6px; font-size: 0.72rem; color: var(--qs-app-muted); margin-top: 3px; }
.qs-live-tutor i { width: 18px; height: 18px; border-radius: 50%; color: #fff; font-style: normal; font-size: 0.6rem; font-weight: 800; display: grid; place-items: center; }
.qs-live-right { display: flex; flex-direction: column; align-items: flex-end; gap: 6px; flex-shrink: 0; }
.qs-live-right small { font-size: 0.68rem; color: var(--qs-app-muted); }

/* -------------------------------------------------------------------------
   Stats band + CTA
   ------------------------------------------------------------------------- */
.qs-stats-band { display: flex; flex-direction: column; gap: 18px; }

.qs-stats-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 16px;
    background: var(--qs-app-card);
    border: 1px solid var(--qs-app-border);
    border-radius: var(--qs-app-radius-lg);
    box-shadow: var(--qs-app-shadow);
    padding: 22px;
}
.qs-stat-item { display: flex; align-items: center; gap: 14px; }
.qs-stat-item > svg { flex-shrink: 0; }
.qs-stat-item strong { font-size: 1.6rem; font-weight: 800; color: var(--qs-app-text); letter-spacing: -0.02em; line-height: 1; }
.qs-stat-item em { font-style: normal; font-size: 1.1rem; font-weight: 800; color: var(--qs-app-primary); margin-left: 2px; }
.qs-stat-item small { display: block; font-size: 0.72rem; color: var(--qs-app-muted); margin-top: 4px; }

.qs-trusted-cta {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 20px;
    background: var(--qs-gradient-primary);
    border-radius: var(--qs-app-radius-lg);
    padding: 24px 30px;
    position: relative;
    overflow: hidden;
}
.qs-trusted-cta::before {
    content: "";
    position: absolute;
    top: -70px;
    right: -40px;
    width: 220px;
    height: 220px;
    border-radius: 50%;
    background: radial-gradient(circle, rgba(255, 255, 255, 0.22), transparent 70%);
}
.qs-trusted-left { position: relative; }
.qs-trusted-badge {
    display: inline-block;
    font-size: 0.74rem;
    font-weight: 800;
    letter-spacing: 0.03em;
    color: #fff;
    background: rgba(255, 255, 255, 0.16);
    border: 1px solid rgba(255, 255, 255, 0.3);
    padding: 6px 12px;
    border-radius: 999px;
    margin-bottom: 10px;
}
.qs-trusted-left p { margin: 0; font-size: 0.9rem; color: rgba(255, 255, 255, 0.92); max-width: 520px; }

/* -------------------------------------------------------------------------
   Testimonials
   ------------------------------------------------------------------------- */
.qs-testimonial-slider {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 16px;
}
.qs-testimonial-card {
    background: var(--qs-app-card);
    border: 1px solid var(--qs-app-border);
    border-radius: var(--qs-app-radius);
    box-shadow: var(--qs-app-shadow);
    padding: 20px;
    display: flex;
    flex-direction: column;
    transition: transform 0.22s ease, box-shadow 0.22s ease;
}
.qs-testimonial-card:hover { transform: translateY(-4px); box-shadow: var(--qs-app-shadow-lg); }
.qs-t-stars { display: flex; gap: 2px; color: #f59e0b; font-size: 0.9rem; margin-bottom: 10px; }
.qs-t-text { margin: 0 0 16px; font-size: 0.84rem; line-height: 1.6; color: var(--qs-app-text-soft); flex: 1; }
.qs-t-author { display: flex; align-items: center; gap: 10px; }
.qs-t-avatar {
    width: 38px;
    height: 38px;
    border-radius: 50%;
    color: #fff;
    font-size: 0.78rem;
    font-weight: 800;
    display: grid;
    place-items: center;
    flex-shrink: 0;
}
.qs-t-author strong { display: block; font-size: 0.8rem; color: var(--qs-app-text); }
.qs-t-author small { font-size: 0.68rem; color: var(--qs-app-muted); }

/* -------------------------------------------------------------------------
   Trusted logos
   ------------------------------------------------------------------------- */
.qs-trusted-section { padding: 6px 0; }
.qs-trusted-label {
    display: block;
    text-align: center;
    margin-bottom: 12px;
    font-size: 0.78rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 1.5px;
    color: var(--qs-app-text-soft);
}
.qs-trusted-row {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    justify-content: center;
    gap: 14px 40px;
    opacity: 0.75;
}
.qs-trusted-logo {
    font-size: 0.95rem;
    color: var(--qs-app-text-soft);
    letter-spacing: 0.01em;
    white-space: nowrap;
    transition: opacity 0.2s ease;
}

/* -------------------------------------------------------------------------
   Blue CTA banner
   ------------------------------------------------------------------------- */
.qs-cta-banner { padding: 0; }
.qs-cta-inner {
    position: relative;
    overflow: hidden;
    background: var(--qs-gradient-primary);
    border-radius: 26px;
    text-align: center;
    padding: 56px 32px 48px;
}
.qs-cta-bg-shape { position: absolute; border-radius: 50%; pointer-events: none; }
.qs-cta-shape-1 { width: 320px; height: 320px; background: rgba(255, 255, 255, 0.14); top: -160px; left: -80px; }
.qs-cta-shape-2 { width: 280px; height: 280px; background: rgba(255, 255, 255, 0.1); bottom: -150px; right: -60px; }
.qs-cta-title { margin: 0 0 10px; font-size: clamp(1.5rem, 3vw, 2.1rem); font-weight: 800; color: #fff; letter-spacing: -0.02em; position: relative; }
.qs-cta-sub { margin: 0 auto 26px; max-width: 560px; font-size: 0.95rem; color: rgba(255, 255, 255, 0.9); position: relative; }
.qs-cta-actions { display: flex; justify-content: center; gap: 14px; flex-wrap: wrap; position: relative; }
.qs-cta-note { margin: 16px 0 0; font-size: 0.72rem; color: rgba(255, 255, 255, 0.75); position: relative; }

/* -------------------------------------------------------------------------
   Right sidebar widgets
   ------------------------------------------------------------------------- */
.qs-widget {
    background: var(--qs-app-card);
    border: 1px solid var(--qs-app-border);
    border-radius: var(--qs-app-radius-lg);
    box-shadow: var(--qs-app-shadow);
    padding: 20px;
    transition: box-shadow 0.25s ease;
}
.qs-widget:hover { box-shadow: var(--qs-app-shadow-md); }

.qs-widget-head { display: flex; align-items: center; justify-content: space-between; gap: 10px; margin-bottom: 16px; }
.qs-widget-head h3 { margin: 0; font-size: 0.95rem; font-weight: 800; letter-spacing: -0.01em; }
.qs-widget-more { font-size: 0.74rem; font-weight: 700; color: var(--qs-app-muted); text-decoration: none; }
.qs-widget-more:hover { color: var(--qs-app-primary); }

/* Welcome */
.qs-wlvl-badge {
    font-size: 0.68rem;
    font-weight: 800;
    color: var(--qs-app-primary);
    background: var(--qs-app-primary-soft);
    border: 1px solid var(--qs-app-primary-border);
    padding: 4px 10px;
    border-radius: 999px;
}
.qs-welcome-user { display: flex; align-items: center; gap: 12px; margin-bottom: 16px; }
.qs-welcome-avatar { position: relative; flex-shrink: 0; }
.qs-welcome-avatar svg { display: block; }
.qs-welcome-avatar i {
    position: absolute;
    right: 1px;
    bottom: 1px;
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: #22c55e;
    border: 2.5px solid var(--qs-app-card);
}
.qs-welcome-name { display: block; font-size: 1rem; color: var(--qs-app-text); line-height: 1.2; }
.qs-welcome-role { font-size: 0.72rem; color: var(--qs-app-muted); }

.qs-xp-top { display: flex; justify-content: space-between; align-items: baseline; margin-bottom: 8px; }
.qs-xp-top span { font-size: 0.72rem; color: var(--qs-app-muted); font-weight: 600; }
.qs-xp-top strong { font-size: 1.05rem; color: var(--qs-app-primary); }
.qs-xp-bar { height: 10px; }
.qs-xp-bottom { display: flex; justify-content: space-between; margin-top: 7px; }
.qs-xp-bottom small { font-size: 0.66rem; color: var(--qs-app-muted); }

.qs-badges-row { display: flex; gap: 8px; margin-top: 14px; }
.qs-badge-item {
    width: 38px;
    height: 38px;
    border-radius: 12px;
    background: var(--qs-app-card-soft);
    border: 1px solid var(--qs-app-border);
    display: grid;
    place-items: center;
    font-size: 1.05rem;
    transition: transform 0.18s ease, border-color 0.18s ease;
}
.qs-badge-item:hover { transform: translateY(-3px) rotate(-6deg); border-color: var(--qs-app-primary-border); }
.qs-badge-locked { opacity: 0.5; }

/* Streak calendar */
.qs-streak-fire { display: inline-flex; align-items: center; gap: 4px; font-size: 0.78rem; color: var(--qs-app-muted); }
.qs-streak-fire b { font-size: 0.9rem; color: #ea580c; }
html[data-theme="dark"] .qs-streak-fire b { color: #fb923c; }

.qs-streak-cal { display: grid; grid-template-columns: 22px 1fr; gap: 8px; margin-bottom: 14px; }
.qs-streak-rows { display: flex; flex-direction: column; gap: 4px; }
.qs-streak-row-label { height: 26px; display: grid; place-items: center; font-size: 0.58rem; font-weight: 700; color: var(--qs-app-faint); }
.qs-streak-days { display: grid; grid-template-columns: repeat(7, 1fr); gap: 4px; }
.qs-streak-day {
    height: 26px;
    border-radius: 8px;
    display: grid;
    place-items: center;
    font-size: 0.64rem;
    font-weight: 600;
    color: var(--qs-app-text-soft);
    background: var(--qs-app-card-soft);
    border: 1px solid var(--qs-app-border);
}
.qs-streak-empty { background: transparent; border-color: transparent; }
.qs-streak-on { background: rgba(249, 115, 22, 0.14); border-color: rgba(249, 115, 22, 0.35); color: #c2410c; font-weight: 800; }
html[data-theme="dark"] .qs-streak-on { background: rgba(251, 146, 60, 0.16); color: #fb923c; }
.qs-streak-today { background: #ea580c; border-color: #ea580c; color: #fff; box-shadow: 0 0 0 3px rgba(234, 88, 12, 0.25); }
html[data-theme="dark"] .qs-streak-today { background: #fb923c; border-color: #fb923c; color: #111827; }

.qs-streak-stats { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; margin-bottom: 12px; }
.qs-streak-stats div { background: var(--qs-app-card-soft); border: 1px solid var(--qs-app-border); border-radius: 12px; padding: 10px; text-align: center; }
.qs-streak-stats strong { display: block; font-size: 0.9rem; color: var(--qs-app-text); }
.qs-streak-stats small { font-size: 0.66rem; color: var(--qs-app-muted); }
.qs-streak-motivate { margin: 0; font-size: 0.72rem; line-height: 1.5; color: var(--qs-app-muted); background: var(--qs-app-primary-soft); border: 1px dashed var(--qs-app-primary-border); border-radius: 12px; padding: 10px 12px; }

/* Today's goal */
.qs-goal-pct { font-size: 0.7rem; font-weight: 800; color: #059669; background: rgba(16, 185, 129, 0.12); padding: 4px 10px; border-radius: 999px; }
.qs-goal-ring {
    position: relative;
    width: 104px;
    height: 104px;
    margin: 4px auto 16px;
    border-radius: 50%;
    background: conic-gradient(#10b981 0deg, #10b981 270deg, var(--qs-app-border) 270deg, var(--qs-app-border) 360deg);
    display: grid;
    place-items: center;
}
.qs-goal-ring::before {
    content: "";
    position: absolute;
    inset: 12px;
    border-radius: 50%;
    background: var(--qs-app-card);
}
.qs-goal-ring > * { position: relative; }
.qs-goal-ring-ico { font-size: 1.3rem; margin-bottom: 2px; }
.qs-goal-ring strong { font-size: 1.05rem; color: var(--qs-app-text); }

.qs-goal-tasks { list-style: none; margin: 0; padding: 0; display: flex; flex-direction: column; gap: 9px; }
.qs-goal-tasks li {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 0.8rem;
    color: var(--qs-app-text-soft);
}
.qs-goal-tasks li em { font-style: normal; margin-left: auto; font-size: 0.7rem; color: var(--qs-app-muted); font-weight: 700; }
.qs-goal-check {
    width: 20px;
    height: 20px;
    border-radius: 50%;
    border: 1.5px solid var(--qs-app-border-strong);
    display: grid;
    place-items: center;
    font-size: 0.62rem;
    color: transparent;
    flex-shrink: 0;
}
.qs-goal-done .qs-goal-check { background: #10b981; border-color: #10b981; color: #fff; }
.qs-goal-done { opacity: 0.85; }
.qs-goal-done em { color: #10b981; }

/* Leaderboard */
.qs-lb-tabs { display: flex; gap: 6px; background: var(--qs-app-card-soft); border: 1px solid var(--qs-app-border); border-radius: 12px; padding: 4px; margin-bottom: 14px; }
.qs-lb-tab {
    flex: 1;
    border: none;
    background: transparent;
    padding: 7px 4px;
    border-radius: 9px;
    font-size: 0.72rem;
    font-weight: 700;
    color: var(--qs-app-muted);
    cursor: pointer;
    transition: background 0.18s ease, color 0.18s ease;
}
.qs-lb-tab:hover { color: var(--qs-app-text); }
.qs-lb-active { background: var(--qs-app-card); color: var(--qs-app-primary) !important; box-shadow: var(--qs-app-shadow); }

.qs-lb-board { display: flex; flex-direction: column; gap: 4px; }
.qs-lb-row {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 8px 10px;
    border-radius: 12px;
    transition: background 0.15s ease;
}
.qs-lb-row:hover { background: var(--qs-app-card-soft); }
.qs-lb-rank { width: 24px; font-size: 0.78rem; font-weight: 800; color: var(--qs-app-muted); text-align: center; flex-shrink: 0; }
.qs-lb-top { color: #f59e0b; }
.qs-lb-avatar { width: 32px; height: 32px; border-radius: 50%; color: #fff; font-size: 0.7rem; font-weight: 800; display: grid; place-items: center; flex-shrink: 0; }
.qs-lb-name { flex: 1; font-size: 0.8rem; font-weight: 600; color: var(--qs-app-text); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.qs-lb-name i { font-style: normal; font-weight: 600; color: var(--qs-app-muted); }
.qs-lb-xp { font-size: 0.7rem; font-weight: 700; color: var(--qs-app-muted); flex-shrink: 0; }
.qs-lb-you { background: var(--qs-app-primary-soft); border: 1px solid var(--qs-app-primary-border); }
.qs-lb-you .qs-lb-name { color: var(--qs-app-primary); font-weight: 800; }

/* Reward card */
.qs-widget-reward {
    position: relative;
    overflow: hidden;
    background: var(--qs-gradient-purple);
    border: none;
    color: #fff;
    text-align: center;
    padding: 26px 22px 24px;
}
.qs-reward-glow {
    position: absolute;
    width: 180px;
    height: 180px;
    border-radius: 50%;
    background: radial-gradient(circle, rgba(255, 255, 255, 0.28), transparent 70%);
    top: -70px;
    right: -50px;
    pointer-events: none;
}
.qs-reward-illustration { margin-bottom: 10px; }
.qs-reward-illustration svg { margin: 0 auto; animation: qs-reward-bob 3.2s ease-in-out infinite; }
@keyframes qs-reward-bob {
    0%, 100% { transform: translateY(0) rotate(-2deg); }
    50% { transform: translateY(-8px) rotate(2deg); }
}
.qs-reward-title { margin: 0 0 6px; font-size: 1.05rem; font-weight: 800; color: #fff; }
.qs-reward-desc { margin: 0 0 16px; font-size: 0.78rem; line-height: 1.55; color: rgba(255, 255, 255, 0.9); }
.qs-widget-reward .qs-btn-white { color: #6d28d9; }

/* -------------------------------------------------------------------------
   Mobile bottom navigation — floating glass bar with pill indicator
   ------------------------------------------------------------------------- */
.qs-mobile-nav {
    height: 66px;
    padding: 0 8px;
    border-radius: 28px;
    border: 1px solid var(--qs-app-border);
    background: var(--qs-app-card);
    background: color-mix(in srgb, var(--qs-app-card) 76%, transparent);
    backdrop-filter: blur(20px) saturate(1.6);
    -webkit-backdrop-filter: blur(20px) saturate(1.6);
    z-index: 1400;
    box-shadow: 0 8px 32px -6px rgba(15, 23, 42, 0.18), 0 2px 8px rgba(15, 23, 42, 0.06), inset 0 1px 0 rgba(255, 255, 255, 0.55);
    justify-content: space-between;
    align-items: center;
    -webkit-user-select: none;
    user-select: none;
}
.qs-mobile-nav-item {
    flex: 0 1 56px;
    min-width: 44px;
    height: 52px;
    gap: 3px;
    font-size: 10px;
    font-weight: 600;
    letter-spacing: 0.02em;
    border-radius: 16px;
    color: var(--qs-app-muted);
    transition: color 0.25s ease, transform 0.2s ease;
}
.qs-mobile-nav-item:hover,
.qs-mobile-nav-item.qs-mobile-nav-active,
.qs-mobile-nav-item.active { color: var(--qs-app-primary); }
.qs-mobile-nav-pill {
    top: 6px;
    width: 46px;
    height: 30px;
    border-radius: 12px;
    background: var(--qs-app-primary);
    background: color-mix(in srgb, var(--qs-app-primary) 14%, transparent);
}
.qs-mobile-nav-item.qs-mobile-nav-active .qs-mobile-nav-pill,
.qs-mobile-nav-item.active .qs-mobile-nav-pill { opacity: 1; transform: translateX(-50%) scale(1); }
.qs-mobile-nav-item.qs-mobile-nav-active .qs-mobile-nav-label,
.qs-mobile-nav-item.active .qs-mobile-nav-label { font-weight: 700; }
.qs-mobile-nav-fab {
    top: -26px;
    width: 58px;
    height: 58px;
    margin: 0 2px;
    border-radius: 20px;
    background: var(--qs-gradient-primary);
    border: 4px solid var(--qs-app-bg);
    box-shadow: 0 12px 26px -8px rgba(37, 99, 235, 0.6), 0 2px 6px rgba(37, 99, 235, 0.25);
    transition: transform 0.25s cubic-bezier(0.34, 1.56, 0.64, 1), box-shadow 0.25s ease;
}
.qs-mobile-nav-fab:hover { transform: translateY(-2px) scale(1.05); }
.qs-mobile-nav-fab:active { transform: scale(0.92); }
html[data-theme="dark"] .qs-mobile-nav-fab { border-color: var(--qs-app-bg); }
html[data-theme="dark"] .qs-mobile-nav { background: var(--qs-app-card); background: color-mix(in srgb, var(--qs-app-card) 72%, transparent); box-shadow: 0 8px 32px -6px rgba(2, 6, 23, 0.55), 0 2px 8px rgba(2, 6, 23, 0.35), inset 0 1px 0 rgba(255, 255, 255, 0.06); }

.qs-mobile-dark-toggle {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 3px;
    padding: 0;
    background: none;
    border: none;
    cursor: pointer;
    font-family: inherit;
    font-size: 10px;
    font-weight: 600;
    letter-spacing: 0.02em;
    color: var(--qs-app-muted);
    -webkit-tap-highlight-color: transparent;
}
.qs-mobile-dark-toggle:hover { color: var(--qs-app-primary); }
.qs-mobile-dark-toggle:focus-visible {
    outline: 2px solid var(--qs-app-primary);
    outline-offset: 2px;
    border-radius: 16px;
}

/* -------------------------------------------------------------------------
   Reveal on scroll
   ------------------------------------------------------------------------- */
.qs-reveal { opacity: 0; transform: translateY(24px); transition: opacity 0.6s ease, transform 0.6s ease; }
.qs-reveal.qs-in-view { opacity: 1; transform: translateY(0); }

@media (prefers-reduced-motion: reduce) {
    .qs-reveal { opacity: 1; transform: none; transition: none; }
    .qs-hero-float, .qs-hero-illustration svg, .qs-badge-new { animation: none; }
    html { scroll-behavior: auto; }
}

/* -------------------------------------------------------------------------
   Tablet / laptop
   ------------------------------------------------------------------------- */
@media (max-width: 1400px) {
    .qs-feature-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); }
    .qs-testimonial-slider { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 1280px) {
    .qs-app-content { padding: 22px 22px 48px; gap: 20px; }
    .qs-content-row { grid-template-columns: 1fr 1fr; }
    .qs-panel-live { grid-column: 1 / -1; }
    .qs-hero-grid { gap: 20px; }
    .qs-float-a { left: 0; }
    .qs-float-b { right: 0; }
}

@media (max-width: 1120px) {
    :root { --qs-app-sidebar-visible: 0; }
    .qs-app-sidebar { transform: translateX(-100%); }
    body.qs-sidebar-open .qs-app-sidebar { transform: translateX(0); }
    .qs-sidebar-open { display: grid; }
    .qs-app-body { margin-left: 0; }
    .qs-app-content { grid-template-columns: minmax(0, 1fr); }
    .qs-hero-grid { grid-template-columns: minmax(0, 1fr); }
    .qs-hero-visual { max-width: 480px; margin: 0 auto; }
}

@media (max-width: 900px) {
    .qs-app-topbar { padding: 0 16px; }
    .qs-topbar-search { max-width: 100%; }
    .qs-profile-meta, .qs-profile-chev { display: none; }
    .qs-topbar-signup { display: inline-flex; }
    .qs-feature-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
    .qs-content-row { grid-template-columns: minmax(0, 1fr); }
    .qs-panel-live { grid-column: auto; }
    .qs-testimonial-slider {
        display: flex;
        overflow-x: auto;
        scroll-snap-type: x mandatory;
        gap: 14px;
        padding: 4px 2px 12px;
        scrollbar-width: thin;
    }
    .qs-testimonial-card { flex: 0 0 82%; scroll-snap-align: start; }
}

/* -------------------------------------------------------------------------
   Mobile
   ------------------------------------------------------------------------- */
@media (max-width: 767px) {
    .qs-app-content { padding: 16px 14px 96px; gap: 16px; }
    .qs-main-content { gap: 20px; }
    .qs-topbar-search { display: none; }
    .qs-search-open-mobile { display: grid; }
    .qs-topbar-mobile-brand { display: flex; }
    .qs-app-topbar { gap: 8px; padding: 0 12px; }
    .qs-topbar-left { gap: 10px; }
    .qs-topbar-right { gap: 6px; }
    .qs-topbar-mobile-brand { gap: 6px; }
    .qs-topbar-mobile-brand svg { width: 26px; height: 26px; }
    .qs-topbar-mobile-brand span { font-size: 0.95rem; }
    .qs-icon-btn { width: 38px; height: 38px; }

    .qs-home-hero { padding: 26px 20px; border-radius: 20px; }
    .qs-hero-title { font-size: clamp(1.55rem, 6.4vw, 2rem); }
    .qs-hero-sub { font-size: 0.88rem; }
    .qs-hero-search { padding-left: 14px; }
    .qs-hero-search .qs-btn { padding: 11px 16px; }
    .qs-hero-actions { flex-direction: column; align-items: stretch; }
    .qs-hero-actions .qs-btn { width: 100%; }
    .qs-float-a { top: 2%; left: -2%; }
    .qs-float-b { bottom: 14%; right: -2%; }
    .qs-float-c { bottom: -4%; left: 6%; }
    .qs-hero-float { padding: 8px 10px 8px 8px; }
    .qs-hero-float strong { font-size: 0.72rem; }
    .qs-hero-float small { font-size: 0.6rem; }

    .qs-section-title { font-size: 1.15rem; }
    .qs-section-head { align-items: center; }

    .qs-feature-grid { gap: 12px; }
    .qs-feature-card { padding: 18px 15px 15px; }
    .qs-fc-icon { width: 46px; height: 46px; margin-bottom: 12px; }
    .qs-fc-title { font-size: 0.9rem; }
    .qs-fc-desc { font-size: 0.75rem; margin-bottom: 12px; }

    .qs-aitool-card { width: 220px; }
    .qs-panel { padding: 16px; }
    .qs-stats-grid { grid-template-columns: 1fr 1fr; padding: 18px; }
    .qs-stat-item { gap: 10px; }
    .qs-stat-item strong { font-size: 1.3rem; }
    .qs-trusted-cta { flex-direction: column; text-align: center; padding: 22px 20px; }
    .qs-cta-inner { padding: 44px 22px 38px; border-radius: 20px; }
    .qs-cta-actions { flex-direction: column; align-items: stretch; }
    .qs-cta-actions .qs-btn { width: 100%; }
    .qs-trusted-row { gap: 12px 24px; }
    .qs-trusted-logo { font-size: 0.82rem; }

    .qs-learning-stats { grid-template-columns: repeat(3, 1fr); }
    .qs-live-right small { display: none; }
    .qs-live-item { padding: 10px 6px; }
    .qs-mobile-nav { display: flex; }
}

@media (max-width: 420px) {
    .qs-hero-float { display: none; }
    .qs-feature-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
    .qs-stat-item { flex-direction: column; align-items: flex-start; gap: 6px; }
    .qs-profile-btn { padding: 4px; }
    .qs-search-kbd { display: none; }
}

/* -------------------------------------------------------------------------
   Dark mode refinements
   ------------------------------------------------------------------------- */
html[data-theme="dark"] body.qs-app-shell .qs-app-sidebar { background: var(--qs-app-card); }
html[data-theme="dark"] .qs-hero-search { background: rgba(15, 23, 42, 0.4); }
html[data-theme="dark"] .qs-arena-tag { background: rgba(15, 23, 42, 0.5); }
html[data-theme="dark"] .qs-stats-grid,
html[data-theme="dark"] .qs-panel,
html[data-theme="dark"] .qs-feature-card,
html[data-theme="dark"] .qs-aitool-card,
html[data-theme="dark"] .qs-testimonial-card,
html[data-theme="dark"] .qs-widget { background: var(--qs-app-card); }

/* -------------------------------------------------------------------------
   Recent search chips container
   ------------------------------------------------------------------------- */
.qs-search-chips { display: flex; flex-wrap: wrap; gap: 8px; }

/* -------------------------------------------------------------------------
   Mobile full-screen search overlay
   ------------------------------------------------------------------------- */
.qs-mobile-search-overlay {
    position: fixed;
    inset: 0;
    z-index: 1500;
    background: var(--qs-app-card);
    opacity: 0;
    visibility: hidden;
    transform: translateY(14px);
    transition: opacity 0.24s ease, transform 0.24s ease, visibility 0.24s ease;
}
.qs-mobile-search-overlay.qs-ms-open { opacity: 1; visibility: visible; transform: translateY(0); }
.qs-ms-head { padding: 12px 16px; border-bottom: 1px solid var(--qs-app-border); }
.qs-ms-form {
    display: flex;
    align-items: center;
    gap: 10px;
    border: 1.5px solid var(--qs-app-border-strong);
    border-radius: 14px;
    padding: 6px 8px 6px 14px;
    background: var(--qs-app-card-soft);
    transition: border-color 0.2s ease, box-shadow 0.2s ease;
}
.qs-ms-form:focus-within { border-color: var(--qs-app-primary); box-shadow: 0 0 0 4px var(--qs-app-primary-soft); }
.qs-ms-form > svg { color: var(--qs-app-muted); flex-shrink: 0; }
.qs-ms-input {
    flex: 1;
    min-width: 0;
    border: none;
    background: transparent;
    padding: 10px 0;
    color: var(--qs-app-text);
    font-size: 0.92rem;
}
.qs-ms-input:focus { outline: none; }
.qs-ms-input::placeholder { color: var(--qs-app-muted); }
.qs-ms-close {
    width: 34px;
    height: 34px;
    border: none;
    border-radius: 10px;
    background: var(--qs-app-card);
    color: var(--qs-app-muted);
    font-size: 1.3rem;
    line-height: 1;
    cursor: pointer;
    flex-shrink: 0;
    transition: color 0.18s ease, background 0.18s ease;
}
.qs-ms-close:hover { color: var(--qs-app-text); background: var(--qs-app-border); }
.qs-ms-body {
    padding: 18px 16px;
    display: flex;
    flex-direction: column;
    gap: 18px;
    max-height: calc(100vh - 92px);
    overflow-y: auto;
}
.qs-ms-body .qs-search-group:not(:first-child) { border-top: 1px solid var(--qs-app-border); padding-top: 18px; }

/* Live classes */
.qs-live-empty { font-size: 0.85rem; color: var(--qs-app-muted); margin: 0; padding: 12px 4px; }
.qs-live-item-link { text-decoration: none; color: inherit; }
.qs-live-item-link:hover .qs-live-topic { color: var(--qs-app-primary); }
.qs-live-list-lg .qs-live-item { padding: 16px 14px; }
.qsp-live-thumb { margin: 0 0 18px; border-radius: var(--qs-app-radius-lg); overflow: hidden; }
.qsp-live-thumb img { width: 100%; height: auto; display: block; object-fit: cover; }
.qsp-live-actions { display: flex; gap: 10px; flex-wrap: wrap; margin-top: 6px; }
.qsp-live-actions .qsp-btn { margin: 0; }
.qsp-question-sub { font-size: 0.95rem; color: var(--qs-app-muted); margin: 4px 0 0; line-height: 1.6; }
.qsp-live-archive-head { margin-bottom: 18px; }
.qsp-live-archive-head .qs-section-kicker { margin-bottom: 6px; }

/* -------------------------------------------------------------------------
   For Schools — School Management Portal
   ------------------------------------------------------------------------- */
.qs-kicker-schools { color: #7c3aed; }
html[data-theme="dark"] .qs-kicker-schools { color: #a78bfa; }

.qs-schools-section { padding-top: 6px; }

.qs-schools-grid {
    display: grid;
    grid-template-columns: minmax(0, 1.15fr) minmax(0, 1fr);
    gap: 24px;
    align-items: start;
}

.qs-schools-features {
    list-style: none;
    margin: 0;
    padding: 0;
    display: flex;
    flex-direction: column;
    gap: 14px;
}

.qs-schools-feature {
    display: flex;
    align-items: flex-start;
    gap: 14px;
    background: var(--qs-app-card);
    border: 1px solid var(--qs-app-border);
    border-radius: var(--qs-app-radius);
    box-shadow: var(--qs-app-shadow);
    padding: 16px;
    transition: box-shadow 0.25s ease, border-color 0.25s ease, transform 0.25s ease;
}
.qs-schools-feature:hover { box-shadow: var(--qs-app-shadow-md); border-color: var(--qs-app-primary-border); transform: translateY(-2px); }

.qs-schools-fico {
    width: 44px;
    height: 44px;
    flex-shrink: 0;
    border-radius: 12px;
    display: grid;
    place-items: center;
    background: rgba(124, 58, 237, 0.12);
    color: #7c3aed;
    transition: background 0.25s ease, color 0.25s ease, transform 0.25s ease;
}
.qs-schools-feature:hover .qs-schools-fico { background: var(--qs-gradient-purple); color: #fff; transform: rotate(-5deg) scale(1.05); }

.qs-schools-fbody { min-width: 0; }
.qs-schools-ftitle { display: block; margin: 0 0 4px; font-size: 0.92rem; font-weight: 800; color: var(--qs-app-text); line-height: 1.35; }
.qs-schools-fdesc { margin: 0; font-size: 0.8rem; line-height: 1.55; color: var(--qs-app-muted); }

.qs-schools-right { position: sticky; top: 88px; }

.qs-schools-preview {
    background: var(--qs-app-card);
    border: 1px solid var(--qs-app-border);
    border-radius: var(--qs-app-radius-lg);
    box-shadow: var(--qs-app-shadow-lg);
    overflow: hidden;
}
.qs-schools-preview-head {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
    padding: 16px 18px;
    background: var(--qs-gradient-purple);
    color: #fff;
}
.qs-schools-preview-title { font-weight: 800; font-size: 0.95rem; letter-spacing: -0.01em; }
.qs-schools-preview-badge {
    display: inline-flex;
    align-items: center;
    gap: 5px;
    font-size: 0.7rem;
    font-weight: 800;
    letter-spacing: 0.04em;
    background: rgba(255, 255, 255, 0.18);
    border: 1px solid rgba(255, 255, 255, 0.3);
    border-radius: 999px;
    padding: 4px 10px;
}

.qs-schools-stats {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 10px;
    padding: 16px 18px 0;
}
.qs-schools-stat {
    background: var(--qs-app-card-soft);
    border: 1px solid var(--qs-app-border);
    border-radius: 12px;
    padding: 12px 10px;
    text-align: center;
}
.qs-schools-stat strong { display: block; font-size: 1.25rem; font-weight: 800; color: var(--qs-app-text); letter-spacing: -0.02em; }
.qs-schools-stat span { display: block; margin-top: 2px; font-size: 0.7rem; font-weight: 700; text-transform: uppercase; letter-spacing: 0.05em; color: var(--qs-app-muted); }

.qs-schools-rows { padding: 14px 18px; display: flex; flex-direction: column; gap: 10px; }
.qs-schools-row {
    display: flex;
    align-items: center;
    gap: 12px;
    border: 1px solid var(--qs-app-border);
    border-radius: 12px;
    padding: 10px 12px;
    background: var(--qs-app-card);
    transition: border-color 0.2s ease;
}
.qs-schools-row:hover { border-color: var(--qs-app-primary-border); }
.qs-schools-avatar {
    width: 38px;
    height: 38px;
    flex-shrink: 0;
    border-radius: 10px;
    display: grid;
    place-items: center;
    font-size: 0.7rem;
    font-weight: 800;
    color: #fff;
}
.qs-sch-av-1 { background: linear-gradient(135deg, #10b981, #059669); }
.qs-sch-av-2 { background: linear-gradient(135deg, #f59e0b, #d97706); }
.qs-schools-row-body { min-width: 0; flex: 1; }
.qs-schools-row-body strong { display: block; font-size: 0.82rem; font-weight: 800; color: var(--qs-app-text); line-height: 1.3; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.qs-schools-row-body small { display: block; margin-top: 2px; font-size: 0.72rem; color: var(--qs-app-muted); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.qs-schools-row-tag {
    flex-shrink: 0;
    font-size: 0.65rem;
    font-weight: 800;
    letter-spacing: 0.03em;
    text-transform: uppercase;
    color: #059669;
    background: rgba(16, 185, 129, 0.12);
    border-radius: 999px;
    padding: 4px 10px;
}

.qs-schools-joincode {
    display: flex;
    align-items: center;
    gap: 10px;
    margin: 0 18px 16px;
    border: 1.5px dashed var(--qs-app-primary-border);
    border-radius: 12px;
    padding: 10px 12px;
    background: var(--qs-app-card-soft);
}
.qs-schools-jc-label { font-size: 0.72rem; font-weight: 700; color: var(--qs-app-muted); }
.qs-schools-jc-value { font-size: 0.85rem; font-weight: 800; letter-spacing: 0.06em; color: var(--qs-app-primary-dark); font-family: ui-monospace, SFMono-Regular, Menlo, monospace; }
.qs-schools-jc-copy { margin-left: auto; cursor: pointer; font-size: 0.9rem; color: var(--qs-app-muted); transition: color 0.18s ease; }
.qs-schools-jc-copy:hover { color: var(--qs-app-primary); }

.qs-schools-cta { display: flex; flex-direction: column; gap: 10px; padding: 0 18px 18px; }

@media (max-width: 900px) {
    .qs-schools-grid { grid-template-columns: minmax(0, 1fr); }
    .qs-schools-right { position: static; }
}