/* ════════════════════════════════════════════════════════
   QUESTUDY SCHOOL PORTAL — modern qsch-* design system
   Self-contained. All class names preserved from v1 markup.
   ════════════════════════════════════════════════════════ */

.qsch-wrap {
    --qsch-primary: #6366f1;
    --qsch-primary-strong: #4f46e5;
    --qsch-primary-deep: #4338ca;
    --qsch-primary-soft: #eef2ff;
    --qsch-green: #10b981;
    --qsch-green-soft: #ecfdf5;
    --qsch-amber: #f59e0b;
    --qsch-amber-soft: #fffbeb;
    --qsch-red: #ef4444;
    --qsch-red-soft: #fef2f2;
    --qsch-blue: #2563eb;
    --qsch-blue-soft: #eff6ff;
    --qsch-purple: #8b5cf6;
    --qsch-purple-soft: #f5f3ff;
    --qsch-ink: #0f172a;
    --qsch-muted: #64748b;
    --qsch-faint: #94a3b8;
    --qsch-line: #e6e9f2;
    --qsch-line-strong: #d4d9ea;
    --qsch-bg: #f4f6fb;
    --qsch-card: #ffffff;
    --qsch-soft: #f8fafc;
    --qsch-radius: 20px;
    --qsch-radius-sm: 13px;
    --qsch-shadow-sm: 0 1px 2px rgba(15, 23, 42, 0.05);
    --qsch-shadow: 0 1px 2px rgba(15, 23, 42, 0.04), 0 14px 34px -16px rgba(79, 70, 229, 0.18);
    --qsch-shadow-lg: 0 2px 4px rgba(15, 23, 42, 0.05), 0 26px 54px -18px rgba(79, 70, 229, 0.26);
    --qsch-grad: linear-gradient(135deg, #6366f1 0%, #8b5cf6 100%);
    --qsch-grad-blue: linear-gradient(135deg, #2563eb 0%, #06b6d4 100%);
    --qsch-grad-green: linear-gradient(135deg, #10b981 0%, #14b8a6 100%);
    --qsch-grad-amber: linear-gradient(135deg, #f59e0b 0%, #f97316 100%);
    --qsch-grad-red: linear-gradient(135deg, #ef4444 0%, #f43f5e 100%);

    position: relative;
    max-width: 1180px;
    margin: 0 auto;
    padding: 28px 28px 56px;
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    color: var(--qsch-ink);
    line-height: 1.6;
    background:
        radial-gradient(900px 420px at 12% -10%, rgba(99, 102, 241, 0.09), transparent 60%),
        radial-gradient(700px 380px at 92% -8%, rgba(139, 92, 246, 0.09), transparent 60%),
        var(--qsch-bg);
    border: 1px solid var(--qsch-line);
    border-radius: 28px;
    box-shadow: var(--qsch-shadow-sm), inset 0 1px 0 rgba(255, 255, 255, 0.6);
}

.qsch-wrap *, .qsch-wrap *::before, .qsch-wrap *::after { box-sizing: border-box; }

.qsch-muted { color: var(--qsch-muted); font-size: 13px; }
.qsch-center { text-align: center; }

/* ── Hero ── */
.qsch-hero {
    position: relative;
    text-align: center;
    padding: 44px 20px 36px;
    overflow: hidden;
}
.qsch-hero::before,
.qsch-hero::after {
    content: "";
    position: absolute;
    z-index: 0;
    border-radius: 50%;
    filter: blur(60px);
    pointer-events: none;
}
.qsch-hero::before { width: 260px; height: 260px; left: -60px; top: -80px; background: rgba(99, 102, 241, 0.16); }
.qsch-hero::after { width: 240px; height: 240px; right: -50px; bottom: -90px; background: rgba(139, 92, 246, 0.14); }
.qsch-hero > * { position: relative; z-index: 1; }

.qsch-eyebrow {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    font-size: 12px;
    font-weight: 800;
    letter-spacing: 1.3px;
    text-transform: uppercase;
    color: var(--qsch-primary-strong);
    background: var(--qsch-card);
    border: 1px solid var(--qsch-line);
    box-shadow: var(--qsch-shadow-sm);
    padding: 7px 16px;
    border-radius: 999px;
    margin-bottom: 18px;
}
.qsch-eyebrow::before {
    content: "";
    width: 7px;
    height: 7px;
    border-radius: 50%;
    background: var(--qsch-grad);
    box-shadow: 0 0 0 4px rgba(99, 102, 241, 0.16);
}
.qsch-hero-title {
    margin: 0 0 12px;
    font-size: 42px;
    font-weight: 800;
    line-height: 1.12;
    letter-spacing: -0.035em;
    background: linear-gradient(135deg, #0f172a 0%, #312e81 55%, #6366f1 100%);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
}
.qsch-hero-sub {
    margin: 0 auto;
    font-size: 16px;
    color: var(--qsch-muted);
    max-width: 640px;
}

.qsch-hero-badges {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 8px;
    margin-top: 22px;
}
.qsch-hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-size: 12.5px;
    font-weight: 700;
    color: var(--qsch-muted);
    background: var(--qsch-card);
    border: 1px solid var(--qsch-line);
    border-radius: 999px;
    padding: 7px 13px;
    box-shadow: var(--qsch-shadow-sm);
}
.qsch-hero-badge b { color: var(--qsch-primary-strong); }

/* ── Grids ── */
.qsch-grid-2 {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 22px;
    align-items: start;
}
.qsch-grid-3 {
    display: grid;
    grid-template-columns: 340px 1fr;
    gap: 22px;
    align-items: start;
}
.qsch-grid-3 .qsch-span-2 { grid-column: span 2; }

/* ── Cards ── */
.qsch-card {
    background: var(--qsch-card);
    border: 1px solid var(--qsch-line);
    border-radius: var(--qsch-radius);
    padding: 26px;
    box-shadow: var(--qsch-shadow);
    transition: box-shadow 0.25s ease, transform 0.25s ease, border-color 0.25s ease;
}
.qsch-card:hover { box-shadow: var(--qsch-shadow-lg); border-color: var(--qsch-line-strong); }
.qsch-card-narrow { max-width: 540px; margin: 0 auto; }
.qsch-card-title {
    font-size: 18px;
    font-weight: 800;
    margin: 0 0 18px;
    letter-spacing: -0.02em;
    color: var(--qsch-ink);
}
.qsch-section-title {
    font-size: 12px;
    font-weight: 800;
    margin: 6px 0 14px;
    text-transform: uppercase;
    letter-spacing: 1.1px;
    color: var(--qsch-primary-strong);
    display: flex;
    align-items: center;
    gap: 8px;
}
.qsch-section-title::after {
    content: "";
    flex: 1;
    height: 1px;
    background: var(--qsch-line);
}
.qsch-divider {
    border: none;
    border-top: 1px solid var(--qsch-line);
    margin: 22px 0;
}

/* ── Forms ── */
.qsch-form { display: block; }
.qsch-field { margin-bottom: 16px; }
.qsch-field label {
    display: block;
    font-size: 13px;
    font-weight: 700;
    margin-bottom: 7px;
    color: #334155;
}
.qsch-req { color: var(--qsch-red); }
.qsch-input {
    width: 100%;
    padding: 12px 14px;
    font-size: 14.5px;
    color: var(--qsch-ink);
    background: var(--qsch-card);
    border: 1.5px solid var(--qsch-line-strong);
    border-radius: var(--qsch-radius-sm);
    transition: border-color 0.18s ease, box-shadow 0.18s ease, background 0.18s ease;
    font-family: inherit;
}
.qsch-input::placeholder { color: var(--qsch-faint); }
.qsch-input:hover { border-color: #b9c0da; }
.qsch-input:focus {
    outline: none;
    border-color: var(--qsch-primary);
    background: var(--qsch-card);
    box-shadow: 0 0 0 4px rgba(99, 102, 241, 0.16);
}
.qsch-input-code {
    font-size: 22px;
    font-weight: 800;
    text-align: center;
    letter-spacing: 7px;
    text-transform: uppercase;
    font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
}
.qsch-textarea { resize: vertical; min-height: 78px; }
.qsch-hint { display: block; font-size: 12px; color: var(--qsch-muted); margin-top: 6px; }
.qsch-checks {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}
.qsch-check {
    display: inline-flex;
    align-items: center;
    gap: 7px;
    font-size: 13px;
    font-weight: 600;
    background: var(--qsch-card);
    border: 1px solid var(--qsch-line-strong);
    padding: 8px 12px;
    border-radius: 11px;
    cursor: pointer;
    transition: border-color 0.18s ease, background 0.18s ease;
}
.qsch-check:hover { border-color: var(--qsch-primary); background: var(--qsch-primary-soft); }
.qsch-check input { accent-color: var(--qsch-primary); }

/* ── Buttons ── */
.qsch-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    font-size: 13.5px;
    font-weight: 700;
    padding: 11px 18px;
    border-radius: 12px;
    border: 1px solid var(--qsch-line-strong);
    background: var(--qsch-card);
    color: #334155;
    cursor: pointer;
    transition: transform 0.16s ease, box-shadow 0.22s ease, background 0.18s ease, color 0.18s ease, border-color 0.18s ease;
    text-decoration: none;
    line-height: 1.4;
    font-family: inherit;
}
.qsch-btn:hover { transform: translateY(-1px); border-color: var(--qsch-primary); color: var(--qsch-primary-strong); box-shadow: var(--qsch-shadow-sm); }
.qsch-btn:active { transform: translateY(0) scale(0.98); }
.qsch-btn:focus-visible { outline: 2px solid var(--qsch-primary); outline-offset: 2px; }
.qsch-btn[disabled] { opacity: 0.55; cursor: not-allowed; transform: none; }
.qsch-btn-primary {
    background: var(--qsch-grad);
    border-color: transparent;
    color: #fff;
    box-shadow: 0 10px 22px -10px rgba(99, 102, 241, 0.55);
}
.qsch-btn-primary:hover { background: var(--qsch-grad); color: #fff; transform: translateY(-1px); box-shadow: 0 14px 30px -12px rgba(99, 102, 241, 0.7); }
.qsch-btn-danger { color: var(--qsch-red); border-color: #fecaca; background: var(--qsch-card); }
.qsch-btn-danger:hover { background: var(--qsch-red-soft); color: var(--qsch-red); border-color: var(--qsch-red); }
.qsch-btn-small { padding: 7px 12px; font-size: 12.5px; border-radius: 10px; }
.qsch-btn-block { width: 100%; }
.qsch-btn-icon {
    width: 30px;
    height: 30px;
    padding: 0;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border-radius: 9px;
    border: 1px solid #fecaca;
    color: var(--qsch-red);
    background: transparent;
    cursor: pointer;
    font-size: 13px;
    transition: background 0.18s ease, transform 0.16s ease;
}
.qsch-btn-icon:hover { background: var(--qsch-red-soft); transform: translateY(-1px); }

/* ── Notices ── */
.qsch-notice {
    padding: 13px 16px;
    border-radius: 12px;
    font-size: 13.5px;
    margin-bottom: 18px;
    border: 1px solid transparent;
    line-height: 1.5;
}
.qsch-notice-error { background: var(--qsch-red-soft); color: #b91c1c; border-color: #fecaca; }
.qsch-notice-success { background: var(--qsch-green-soft); color: #047857; border-color: #a7f3d0; }
.qsch-notice-info { background: var(--qsch-blue-soft); color: #1d4ed8; border-color: #bfdbfe; }
.qsch-notice-warning { background: var(--qsch-amber-soft); color: #b45309; border-color: #fde68a; }

/* ── Feature list (signup) ── */
.qsch-feature-list { list-style: none; margin: 0 0 10px; padding: 0; }
.qsch-feature-list li {
    display: flex;
    gap: 14px;
    padding: 13px 0;
    border-bottom: 1px solid var(--qsch-line);
}
.qsch-feature-list li:last-child { border-bottom: none; }
.qsch-feature-list strong { font-size: 14.5px; display: block; margin-bottom: 3px; color: var(--qsch-ink); }
.qsch-feature-list p { margin: 0; font-size: 13px; color: var(--qsch-muted); }
.qsch-ft-icon {
    width: 42px;
    height: 42px;
    flex-shrink: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 19px;
    background: var(--qsch-primary-soft);
    border: 1px solid #dfe7fe;
    border-radius: 12px;
    box-shadow: var(--qsch-shadow-sm);
}

/* ── Code preview (join) ── */
.qsch-code-preview {
    display: flex;
    align-items: center;
    gap: 13px;
    padding: 15px 16px;
    border-radius: 14px;
    background: linear-gradient(135deg, var(--qsch-green-soft), #f0fdfa);
    border: 1px solid #a7f3d0;
    margin-bottom: 20px;
}
.qsch-preview-icon { font-size: 28px; }
.qsch-code-preview strong { display: block; font-size: 15px; color: var(--qsch-ink); }
.qsch-code-preview .qsch-muted { display: block; }

/* ── Portal hero ── */
.qsch-portal-hero {
    position: relative;
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 20px;
    padding: 28px 30px;
    margin-bottom: 24px;
    border-radius: var(--qsch-radius);
    background:
        radial-gradient(560px 220px at 90% -40%, rgba(139, 92, 246, 0.16), transparent 60%),
        linear-gradient(135deg, rgba(99, 102, 241, 0.10), rgba(139, 92, 246, 0.06)),
        var(--qsch-card);
    border: 1px solid var(--qsch-line);
    box-shadow: var(--qsch-shadow);
    overflow: hidden;
}
.qsch-portal-hero::after {
    content: "";
    position: absolute;
    top: -70px;
    right: -70px;
    width: 220px;
    height: 220px;
    border-radius: 50%;
    background: radial-gradient(circle, rgba(99, 102, 241, 0.14), transparent 70%);
    pointer-events: none;
}
.qsch-portal-title {
    font-size: 32px;
    font-weight: 800;
    letter-spacing: -0.03em;
    margin: 0 0 6px;
    color: var(--qsch-ink);
}
.qsch-portal-sub { color: var(--qsch-muted); font-size: 14.5px; margin: 0; max-width: 560px; }
.qsch-portal-hero-text { position: relative; z-index: 1; }
.qsch-portal-hero-side { position: relative; z-index: 1; display: flex; flex-direction: column; gap: 9px; align-items: flex-end; }

.qsch-role-badge,
.qsch-status-badge {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-size: 11.5px;
    font-weight: 800;
    padding: 6px 13px;
    border-radius: 999px;
    letter-spacing: 0.5px;
    text-transform: uppercase;
    box-shadow: var(--qsch-shadow-sm);
}
.qsch-role-badge::before,
.qsch-status-badge::before {
    content: "";
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: currentColor;
    opacity: 0.7;
}
.qsch-role-admin { background: var(--qsch-primary-soft); color: var(--qsch-primary-strong); }
.qsch-role-teacher { background: var(--qsch-blue-soft); color: #1d4ed8; }
.qsch-role-student { background: var(--qsch-green-soft); color: #047857; }
.qsch-status-active { background: var(--qsch-green-soft); color: #047857; }
.qsch-status-pending { background: var(--qsch-amber-soft); color: #b45309; }
.qsch-status-suspended,
.qsch-status-rejected { background: var(--qsch-red-soft); color: #b91c1c; }

/* ── Stat cards ── */
.qsch-stat-row {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 16px;
    margin-bottom: 26px;
}
.qsch-stat-card {
    position: relative;
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    padding: 18px 20px;
    border-radius: var(--qsch-radius-sm);
    border: 1px solid var(--qsch-line);
    background: var(--qsch-card);
    box-shadow: var(--qsch-shadow-sm);
    overflow: hidden;
    transition: box-shadow 0.25s ease, transform 0.25s ease, border-color 0.25s ease;
}
.qsch-stat-card::after {
    content: "";
    position: absolute;
    inset: 0 0 auto 0;
    height: 3px;
    background: var(--qsch-stat-grad, var(--qsch-grad));
    opacity: 0.9;
}
.qsch-stat-card:hover { transform: translateY(-3px); box-shadow: var(--qsch-shadow); border-color: var(--qsch-line-strong); }
.qsch-stat-icon {
    width: 44px;
    height: 44px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 20px;
    border-radius: 12px;
    margin-bottom: 12px;
    background: var(--qsch-stat-soft, var(--qsch-primary-soft));
    border: 1px solid var(--qsch-line);
    box-shadow: var(--qsch-shadow-sm);
}
.qsch-stat-value { font-size: 26px; font-weight: 800; line-height: 1.1; letter-spacing: -0.02em; color: var(--qsch-ink); }
.qsch-stat-label { font-size: 12px; font-weight: 600; color: var(--qsch-muted); margin-top: 4px; text-transform: uppercase; letter-spacing: 0.5px; }
.qsch-stat-blue { --qsch-stat-grad: var(--qsch-grad-blue); --qsch-stat-soft: var(--qsch-blue-soft); }
.qsch-stat-purple { --qsch-stat-grad: var(--qsch-grad); --qsch-stat-soft: var(--qsch-purple-soft); }
.qsch-stat-green { --qsch-stat-grad: var(--qsch-grad-green); --qsch-stat-soft: var(--qsch-green-soft); }
.qsch-stat-amber { --qsch-stat-grad: var(--qsch-grad-amber); --qsch-stat-soft: var(--qsch-amber-soft); }

/* ── Tabs (segmented control) ── */
.qsch-tabs {
    display: flex;
    flex-wrap: wrap;
    gap: 4px;
    padding: 5px;
    margin-bottom: 22px;
    background: var(--qsch-soft);
    border: 1px solid var(--qsch-line);
    border-radius: 15px;
}
.qsch-tab {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 10px 18px;
    font-size: 13.5px;
    font-weight: 700;
    color: var(--qsch-muted);
    background: transparent;
    border: none;
    border-radius: 11px;
    cursor: pointer;
    font-family: inherit;
    transition: background 0.18s ease, color 0.18s ease, box-shadow 0.18s ease;
}
.qsch-tab:hover { color: var(--qsch-ink); background: rgba(99, 102, 241, 0.07); }
.qsch-tab[data-active="1"] {
    color: var(--qsch-primary-strong);
    background: var(--qsch-card);
    box-shadow: var(--qsch-shadow-sm), 0 6px 18px -8px rgba(79, 70, 229, 0.4);
}
.qsch-tab-icon { font-size: 15px; }

.qsch-panel { display: none; }
.qsch-panel[data-active="1"] { display: block; animation: qschFade 0.24s ease; }
@keyframes qschFade { from { opacity: 0; transform: translateY(6px); } to { opacity: 1; transform: none; } }

/* ── Lists / rows ── */
.qsch-list { display: flex; flex-direction: column; gap: 10px; }
.qsch-list-row {
    display: flex;
    align-items: center;
    gap: 13px;
    padding: 13px 15px;
    border: 1px solid var(--qsch-line);
    border-radius: 13px;
    background: var(--qsch-card);
    transition: box-shadow 0.2s ease, border-color 0.2s ease, transform 0.2s ease;
}
.qsch-list-row:hover { box-shadow: var(--qsch-shadow-sm); border-color: var(--qsch-line-strong); transform: translateY(-1px); }
.qsch-avatar {
    width: 42px;
    height: 42px;
    flex-shrink: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 18px;
    font-weight: 800;
    border-radius: 12px;
    background: var(--qsch-primary-soft);
    color: var(--qsch-primary-strong);
    border: 1px solid #dfe7fe;
}
.qsch-avatar-blue { background: var(--qsch-blue-soft); color: #1d4ed8; border-color: #bfdbfe; }
.qsch-avatar-green { background: var(--qsch-green-soft); color: #047857; border-color: #a7f3d0; }
.qsch-list-main { flex: 1; min-width: 0; }
.qsch-list-main strong { display: block; font-size: 14px; color: var(--qsch-ink); }
.qsch-list-main .qsch-muted { display: block; margin-top: 2px; }
.qsch-list-actions { display: flex; align-items: center; gap: 8px; flex-shrink: 0; flex-wrap: wrap; }

/* ── Chips ── */
.qsch-chip {
    display: inline-flex;
    align-items: center;
    gap: 5px;
    font-size: 11.5px;
    font-weight: 700;
    padding: 5px 11px;
    border-radius: 999px;
    background: var(--qsch-soft);
    color: var(--qsch-muted);
    border: 1px solid var(--qsch-line);
    white-space: nowrap;
}
.qsch-chip-green { background: var(--qsch-green-soft); color: #047857; border-color: #a7f3d0; }
.qsch-chip-amber { background: var(--qsch-amber-soft); color: #b45309; border-color: #fde68a; }
.qsch-chip-blue { background: var(--qsch-blue-soft); color: #1d4ed8; border-color: #bfdbfe; }

/* ── Key/value ── */
.qsch-kv { display: grid; grid-template-columns: 1fr 1fr; gap: 10px 16px; }
.qsch-kv div {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 10px;
    padding: 11px 13px;
    background: var(--qsch-soft);
    border: 1px solid var(--qsch-line);
    border-radius: 11px;
    font-size: 13px;
}
.qsch-kv span { color: var(--qsch-muted); }
.qsch-kv strong { font-size: 15px; color: var(--qsch-ink); }

/* ── Quick actions ── */
.qsch-actions { display: flex; flex-direction: column; gap: 10px; }

/* ── Mini stats ── */
.qsch-mini-stats {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 10px;
    margin-bottom: 18px;
}
.qsch-mini {
    text-align: center;
    padding: 15px 8px;
    background: var(--qsch-soft);
    border: 1px solid var(--qsch-line);
    border-radius: 13px;
    transition: border-color 0.2s ease;
}
.qsch-mini:hover { border-color: var(--qsch-line-strong); }
.qsch-mini-value { display: block; font-size: 24px; font-weight: 800; letter-spacing: -0.02em; background: var(--qsch-grad); -webkit-background-clip: text; background-clip: text; color: transparent; }
.qsch-mini-label { font-size: 11.5px; color: var(--qsch-muted); font-weight: 600; text-transform: uppercase; letter-spacing: 0.4px; }

/* ── Class cards ── */
.qsch-class-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(250px, 1fr)); gap: 16px; }
.qsch-class-card {
    border: 1px solid var(--qsch-line);
    border-radius: 16px;
    padding: 18px;
    background: var(--qsch-card);
    box-shadow: var(--qsch-shadow-sm);
    transition: box-shadow 0.25s ease, transform 0.25s ease, border-color 0.25s ease;
}
.qsch-class-card:hover { transform: translateY(-3px); box-shadow: var(--qsch-shadow); border-color: var(--qsch-line-strong); }
.qsch-class-head { display: flex; justify-content: space-between; align-items: center; margin-bottom: 8px; }
.qsch-class-head h3 { margin: 0; font-size: 15px; font-weight: 800; color: var(--qsch-ink); }
.qsch-class-meta { display: flex; flex-direction: column; gap: 2px; font-size: 12.5px; color: var(--qsch-muted); margin-bottom: 14px; }
.qsch-join-code {
    display: flex;
    align-items: center;
    gap: 9px;
    background: var(--qsch-primary-soft);
    border: 1px solid #dfe7fe;
    border-radius: 11px;
    padding: 8px 11px;
}
.qsch-join-label { font-size: 11px; color: var(--qsch-muted); text-transform: uppercase; letter-spacing: 0.6px; font-weight: 700; }
.qsch-join-code code {
    font-size: 16px;
    font-weight: 800;
    letter-spacing: 3px;
    color: var(--qsch-primary-strong);
    font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
}
.qsch-join-code .qsch-btn { margin-left: auto; }

/* ── Tables ── */
.qsch-table-wrap { overflow-x: auto; border-radius: 14px; border: 1px solid var(--qsch-line); box-shadow: var(--qsch-shadow-sm); }
.qsch-table { width: 100%; border-collapse: collapse; font-size: 13px; }
.qsch-table th {
    text-align: left;
    font-size: 11px;
    font-weight: 800;
    text-transform: uppercase;
    letter-spacing: 0.7px;
    color: var(--qsch-muted);
    background: var(--qsch-soft);
    padding: 12px 14px;
    border-bottom: 1px solid var(--qsch-line);
    white-space: nowrap;
}
.qsch-table td { padding: 12px 14px; border-bottom: 1px solid var(--qsch-line); vertical-align: top; }
.qsch-table tbody tr:last-child td { border-bottom: none; }
.qsch-table tbody tr { transition: background 0.15s ease; }
.qsch-table tbody tr:hover td { background: var(--qsch-primary-soft); }
.qsch-td-actions { text-align: right; white-space: nowrap; }
.qsch-target-cell { padding: 0 !important; background: transparent !important; }
.qsch-target-cell:hover td { background: transparent; }

/* ── Empty state ── */
.qsch-empty {
    text-align: center;
    padding: 40px 16px;
    color: var(--qsch-muted);
    font-size: 13.5px;
    border: 1.5px dashed var(--qsch-line-strong);
    border-radius: 16px;
    background: var(--qsch-soft);
}

/* ── Preview box ── */
.qsch-preview-box {
    display: none;
    margin-top: 12px;
    padding: 13px 15px;
    border-radius: 12px;
    background: var(--qsch-soft);
    border: 1px solid var(--qsch-line);
    font-size: 13px;
    max-height: 240px;
    overflow: auto;
}
.qsch-preview-box.qsch-open { display: block; }
.qsch-preview-box ul { margin: 6px 0 0; padding-left: 18px; }
.qsch-preview-box li { margin-bottom: 4px; }
.qsch-preview-total { font-weight: 800; color: var(--qsch-primary-strong); }

/* ── Activity type toggles ── */
.qsch-activity-filters .qsch-af-practice,
.qsch-activity-filters .qsch-af-past_paper,
.qsch-activity-filters .qsch-af-textbook_chapter,
.qsch-activity-filters .qsch-af-notes,
.qsch-activity-filters .qsch-af-link { display: none; }
.qsch-activity-ref .qsch-af-past_paper,
.qsch-activity-ref .qsch-af-textbook_chapter,
.qsch-activity-ref .qsch-af-notes,
.qsch-activity-ref .qsch-af-link { display: none; }
.qsch-activity-filters[data-type="practice"] .qsch-af-practice { display: block; }
.qsch-activity-filters[data-type="practice"] .qsch-af-practice.qsch-half { display: block; }
.qsch-activity-filters[data-type="past_paper"] .qsch-af-past_paper { display: block; }
.qsch-activity-filters[data-type="textbook_chapter"] .qsch-af-textbook_chapter { display: block; }
.qsch-activity-filters[data-type="notes"] .qsch-af-notes { display: block; }
.qsch-activity-filters[data-type="link"] .qsch-af-link { display: block; }
.qsch-activity-ref[data-type="past_paper"] .qsch-af-past_paper { display: block; }
.qsch-activity-ref[data-type="textbook_chapter"] .qsch-af-textbook_chapter { display: block; }
.qsch-activity-ref[data-type="notes"] .qsch-af-notes { display: block; }
.qsch-activity-ref[data-type="link"] .qsch-af-link { display: block; }

/* ── Inline AJAX panels ── */
.qsch-js-target { margin-top: 8px; }
.qsch-inline-panel {
    padding: 18px;
    border: 1px solid var(--qsch-line);
    border-radius: 14px;
    background: var(--qsch-card);
    box-shadow: var(--qsch-shadow-sm);
}
.qsch-inline-panel h4 { margin: 0 0 14px; font-size: 14px; font-weight: 800; color: var(--qsch-ink); }
.qsch-inline-sub { margin: 20px 0 10px !important; font-size: 12px !important; font-weight: 800; text-transform: uppercase; letter-spacing: 0.6px; color: var(--qsch-muted); }
.qsch-inline-panel .qsch-mini-stats { margin-bottom: 4px; }
.qsch-inline-panel .qsch-table-wrap { margin-top: 4px; }
.qsch-inline-panel .qsch-muted { display: block; }

/* ── Busy state ── */
.qsch-busy { opacity: 0.6; pointer-events: none; }

/* ── Responsive ── */
@media (max-width: 960px) {
    .qsch-wrap { padding: 20px 18px 44px; border-radius: 22px; }
    .qsch-grid-2 { grid-template-columns: 1fr; }
    .qsch-grid-3 { grid-template-columns: 1fr; }
    .qsch-grid-3 .qsch-span-2 { grid-column: auto; }
    .qsch-stat-row { grid-template-columns: repeat(2, 1fr); }
    .qsch-portal-hero { flex-direction: column; align-items: flex-start; }
    .qsch-portal-hero-side { align-items: flex-start; flex-direction: row; }
}
@media (max-width: 560px) {
    .qsch-hero-title { font-size: 30px; }
    .qsch-portal-title { font-size: 25px; }
    .qsch-stat-row { grid-template-columns: 1fr 1fr; gap: 12px; }
    .qsch-stat-card { padding: 15px; }
    .qsch-tabs { padding: 4px; }
    .qsch-tab { flex: 1 1 auto; padding: 9px 12px; }
    .qsch-kv { grid-template-columns: 1fr; }
    .qsch-mini-stats { grid-template-columns: repeat(3, 1fr); }
    .qsch-list-row { flex-wrap: wrap; }
    .qsch-list-actions { width: 100%; justify-content: flex-end; }
}

/* ── Dark mode ── */
@media (prefers-color-scheme: dark) {
    .qsch-wrap {
        --qsch-ink: #e7eaf6;
        --qsch-muted: #9aa2bd;
        --qsch-faint: #6b7392;
        --qsch-line: #232a41;
        --qsch-line-strong: #313a56;
        --qsch-bg: #0d1220;
        --qsch-card: #141b2e;
        --qsch-soft: #101626;
        --qsch-primary-soft: rgba(99, 102, 241, 0.16);
        --qsch-blue-soft: rgba(37, 99, 235, 0.18);
        --qsch-green-soft: rgba(16, 185, 129, 0.15);
        --qsch-amber-soft: rgba(245, 158, 11, 0.15);
        --qsch-red-soft: rgba(239, 68, 68, 0.15);
        --qsch-purple-soft: rgba(139, 92, 246, 0.16);
        --qsch-shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.35);
        --qsch-shadow: 0 1px 2px rgba(0, 0, 0, 0.3), 0 16px 38px -18px rgba(0, 0, 0, 0.55);
        --qsch-shadow-lg: 0 2px 4px rgba(0, 0, 0, 0.35), 0 28px 58px -20px rgba(0, 0, 0, 0.65);
        background:
            radial-gradient(900px 420px at 12% -10%, rgba(99, 102, 241, 0.12), transparent 60%),
            radial-gradient(700px 380px at 92% -8%, rgba(139, 92, 246, 0.1), transparent 60%),
            var(--qsch-bg);
    }
    .qsch-hero-title { background: linear-gradient(135deg, #f8fafc 0%, #c7d2fe 55%, #a5b4fc 100%); -webkit-background-clip: text; background-clip: text; }
    .qsch-field label { color: #c7cbe0; }
    .qsch-btn { color: #d7daea; }
    .qsch-ft-icon, .qsch-avatar, .qsch-join-code { border-color: var(--qsch-line-strong); }
    .qsch-tab[data-active="1"] { box-shadow: 0 6px 18px -8px rgba(0, 0, 0, 0.6); }
    .qsch-stat-card::after { opacity: 1; }
}