:root {
    --bg: #0f0d17;
    --panel: #171327;
    --panel-soft: #201a35;
    --line: rgba(255, 255, 255, 0.12);
    --text: #f5f1e6;
    --muted: #cabfa2;
    --primary: #7c5cff;
    --primary-soft: rgba(124, 92, 255, 0.16);
    --success: #2fbf71;
    --danger: #f55d6c;
    --warning: #f5c451;
    --shadow: 0 20px 50px rgba(0, 0, 0, 0.28);
    --radius: 20px;
}
* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
    font-family: Inter, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
    background: radial-gradient(circle at top, #241a45 0%, var(--bg) 42%);
    color: var(--text);
    min-height: 100vh;
}
a { color: inherit; text-decoration: none; }
code {
    font-family: "SFMono-Regular", Consolas, Monaco, monospace;
    background: rgba(255,255,255,0.08);
    padding: 2px 6px;
    border-radius: 8px;
}
input, select, button, textarea { font: inherit; }
.app-shell { max-width: 1180px; margin: 0 auto; padding: 24px 16px 48px; }
.topbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 20px;
    padding: 10px 0 26px;
}
.topbar h1 { margin: 0; font-size: 1.6rem; }
.eyebrow {
    margin: 0 0 6px;
    text-transform: uppercase;
    letter-spacing: 0.12em;
    color: var(--muted);
    font-size: 0.78rem;
}
.nav { display: flex; gap: 12px; flex-wrap: wrap; align-items: center; }
.nav a,
.nav-button {
    padding: 10px 14px;
    border: 1px solid var(--line);
    border-radius: 999px;
    background: rgba(255,255,255,0.03);
    color: var(--text);
}
.nav-inline-form { margin: 0; }
.nav-button { cursor: pointer; }
.container { display: grid; gap: 20px; }
.card {
    background: linear-gradient(180deg, rgba(255,255,255,0.04), rgba(255,255,255,0.02));
    border: 1px solid var(--line);
    border-radius: var(--radius);
    padding: 24px;
    box-shadow: var(--shadow);
}
.narrow { max-width: 760px; }
.center { text-align: center; margin: 0 auto; }
.align-start { align-items: start; }
.hero {
    display: grid;
    grid-template-columns: 1.5fr 1fr;
    gap: 20px;
    align-items: center;
}
.hero h2, .card h2 {
    margin: 10px 0;
    font-size: clamp(1.8rem, 3vw, 2.6rem);
    line-height: 1.15;
}
.hero p, .lead { color: var(--muted); line-height: 1.7; }
.pill {
    display: inline-flex;
    padding: 8px 12px;
    border-radius: 999px;
    background: var(--primary-soft);
    border: 1px solid rgba(124, 92, 255, 0.35);
    color: #ddd2ff;
    font-size: 0.85rem;
}
.hero-actions { display: flex; gap: 12px; margin-top: 20px; flex-wrap: wrap; }
.centered-actions { justify-content: center; }
.button {
    appearance: none;
    border: 0;
    border-radius: 14px;
    padding: 13px 18px;
    font-weight: 700;
    cursor: pointer;
}
.button.primary { background: var(--primary); color: white; }
.button.secondary {
    background: rgba(255,255,255,0.06);
    color: var(--text);
    border: 1px solid var(--line);
}
.button-block { width: 100%; }
.status-card {
    background: var(--panel-soft);
    border: 1px solid var(--line);
    border-radius: 18px;
    padding: 22px;
}
.status-line.ok { color: #a5f3c0; }
.status-line.error { color: #ffb2bb; }
.grid.two-cols {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 20px;
}
.check-list {
    list-style: none;
    padding: 0;
    margin: 0;
    display: grid;
    gap: 14px;
}
.check-list li {
    display: grid;
    grid-template-columns: auto 1fr;
    gap: 12px;
    align-items: start;
    padding: 14px;
    border-radius: 14px;
    background: rgba(255,255,255,0.03);
    border: 1px solid rgba(255,255,255,0.08);
}
.badge {
    display: inline-flex;
    min-width: 48px;
    justify-content: center;
    border-radius: 999px;
    padding: 6px 10px;
    font-size: 0.82rem;
    font-weight: 700;
}
.badge.success { background: rgba(47,191,113,0.18); color: #bcf3d2; }
.badge.danger { background: rgba(245,93,108,0.16); color: #ffd1d7; }
.meta-list {
    display: grid;
    gap: 14px;
}
.meta-list div {
    padding: 14px;
    border-radius: 14px;
    background: rgba(255,255,255,0.03);
    border: 1px solid rgba(255,255,255,0.08);
}
.meta-list dt {
    font-size: 0.82rem;
    text-transform: uppercase;
    color: var(--muted);
    margin-bottom: 6px;
}
.meta-list dd { margin: 0; }
.compact-list { gap: 10px; }
.tip { color: var(--muted); line-height: 1.7; }
.small-tip { font-size: 0.94rem; }
.feature-grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 16px;
}
.feature-grid > div,
.setup-item {
    padding: 16px;
    border-radius: 16px;
    background: rgba(255,255,255,0.03);
    border: 1px solid rgba(255,255,255,0.08);
}
.feature-grid h4 { margin: 0 0 8px; }
.feature-grid p, .setup-item p { margin: 0; color: var(--muted); line-height: 1.6; }
.setup-grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 14px;
    margin: 20px 0;
}
.steps {
    color: var(--muted);
    line-height: 1.8;
    padding-left: 20px;
}
.alert {
    padding: 16px 18px;
    border-radius: 16px;
    border: 1px solid transparent;
    font-weight: 600;
}
.alert-success {
    background: rgba(47,191,113,0.14);
    border-color: rgba(47,191,113,0.25);
    color: #c8f5da;
}
.alert-error {
    background: rgba(245,93,108,0.14);
    border-color: rgba(245,93,108,0.25);
    color: #ffd9df;
}
.form-grid {
    display: grid;
    gap: 16px;
    margin-top: 22px;
    text-align: left;
}
.two-columns {
    grid-template-columns: repeat(2, minmax(0, 1fr));
}
.field-span-2 { grid-column: span 2; }
.field {
    display: grid;
    gap: 8px;
}
.field span {
    font-size: 0.92rem;
    color: var(--muted);
}
.field input,
.field select {
    width: 100%;
    min-height: 50px;
    border-radius: 14px;
    border: 1px solid rgba(255,255,255,0.10);
    background: rgba(9, 7, 16, 0.65);
    color: var(--text);
    padding: 0 14px;
}
.field input:focus,
.field select:focus {
    outline: none;
    border-color: rgba(124, 92, 255, 0.55);
    box-shadow: 0 0 0 4px rgba(124, 92, 255, 0.16);
}
.switch-field {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 14px 16px;
    border-radius: 16px;
    border: 1px solid rgba(255,255,255,0.10);
    background: rgba(255,255,255,0.03);
}
.switch-field input {
    width: 18px;
    height: 18px;
}
.auth-links {
    display: flex;
    justify-content: center;
    gap: 18px;
    flex-wrap: wrap;
    margin-top: 18px;
    color: var(--muted);
}
.stats-grid {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 20px;
}
.stat-card {
    display: grid;
    gap: 8px;
}
.stat-label {
    color: var(--muted);
    font-size: 0.92rem;
    text-transform: uppercase;
    letter-spacing: 0.08em;
}
.stat-number {
    font-size: clamp(2rem, 4vw, 3rem);
}
.footer {
    display: flex;
    justify-content: space-between;
    gap: 16px;
    flex-wrap: wrap;
    padding-top: 16px;
    color: var(--muted);
    font-size: 0.92rem;
}
@media (max-width: 900px) {
    .hero,
    .grid.two-cols,
    .feature-grid,
    .setup-grid,
    .stats-grid,
    .two-columns { grid-template-columns: 1fr; }
    .field-span-2 { grid-column: span 1; }
}
@media (max-width: 680px) {
    .app-shell { padding-inline: 14px; }
    .topbar { flex-direction: column; align-items: flex-start; }
    .card { padding: 20px; }
    .nav { width: 100%; }
}

textarea {
    width: 100%;
    border-radius: 14px;
    border: 1px solid rgba(255,255,255,0.10);
    background: rgba(9, 7, 16, 0.65);
    color: var(--text);
    padding: 12px 14px;
    resize: vertical;
    min-height: 120px;
}
textarea:focus {
    outline: none;
    border-color: rgba(124, 92, 255, 0.55);
    box-shadow: 0 0 0 4px rgba(124, 92, 255, 0.16);
}
.button.danger {
    background: rgba(245,93,108,0.18);
    color: #ffdfe4;
    border: 1px solid rgba(245,93,108,0.28);
}
.button-small {
    padding: 9px 12px;
    font-size: 0.92rem;
}
.section-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 16px;
    flex-wrap: wrap;
    margin-bottom: 18px;
}
.table-wrap {
    overflow-x: auto;
}
.data-table {
    width: 100%;
    border-collapse: collapse;
    min-width: 760px;
}
.data-table th,
.data-table td {
    text-align: left;
    padding: 14px 12px;
    border-bottom: 1px solid rgba(255,255,255,0.08);
    vertical-align: top;
}
.data-table thead th {
    color: var(--muted);
    text-transform: uppercase;
    letter-spacing: 0.08em;
    font-size: 0.78rem;
}
.table-actions {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
    align-items: center;
}
.checkbox-grid {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 10px;
}
.check-card {
    display: flex;
    gap: 10px;
    align-items: center;
    padding: 12px 14px;
    border-radius: 14px;
    border: 1px solid rgba(255,255,255,0.10);
    background: rgba(255,255,255,0.03);
}
.check-card input {
    width: 18px;
    height: 18px;
}
.list-stack {
    display: grid;
    gap: 12px;
}
.list-item {
    display: flex;
    justify-content: space-between;
    gap: 14px;
    align-items: center;
    padding: 14px 16px;
    border-radius: 16px;
    background: rgba(255,255,255,0.03);
    border: 1px solid rgba(255,255,255,0.08);
}
.list-item p {
    margin: 6px 0 0;
    color: var(--muted);
}
.card-slim {
    padding: 18px;
    border-radius: 16px;
    border: 1px solid rgba(255,255,255,0.08);
    background: rgba(255,255,255,0.03);
}
.admin-stats-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
}
@media (max-width: 900px) {
    .checkbox-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }
}
@media (max-width: 680px) {
    .data-table {
        min-width: 620px;
    }
    .checkbox-grid {
        grid-template-columns: 1fr;
    }
    .list-item {
        flex-direction: column;
        align-items: flex-start;
    }
}


.study-grid {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 16px;
}
.study-card {
    display: grid;
    gap: 12px;
    padding: 18px;
    border-radius: 18px;
    border: 1px solid rgba(255,255,255,0.08);
    background: rgba(255,255,255,0.03);
}
.study-card p { margin: 0; color: var(--muted); line-height: 1.6; }
.study-card-header {
    display: flex;
    justify-content: space-between;
    gap: 12px;
    align-items: center;
    flex-wrap: wrap;
}
.study-status-label {
    font-size: 0.86rem;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: var(--muted);
}
.study-status-known {
    border-color: rgba(47,191,113,0.28);
    background: rgba(47,191,113,0.08);
}
.study-status-review {
    border-color: rgba(245,196,81,0.28);
    background: rgba(245,196,81,0.06);
}
.mini-meta {
    margin: 0;
    padding-left: 18px;
    color: var(--muted);
    display: grid;
    gap: 6px;
}
.study-image-wrap {
    margin: 20px 0;
    display: flex;
    justify-content: center;
}
.study-image {
    max-width: 100%;
    width: min(100%, 340px);
    border-radius: 18px;
    border: 1px solid rgba(255,255,255,0.10);
    display: block;
}
.study-actions-stack {
    display: grid;
    gap: 12px;
    margin: 18px 0 24px;
}
.symbol-item { align-items: flex-start; }
.admin-user-stack { max-height: 700px; overflow: auto; }
.code-block-inline {
    display: inline-block;
    word-break: break-all;
    line-height: 1.6;
}
@media (max-width: 900px) {
    .study-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (max-width: 680px) {
    .study-grid { grid-template-columns: 1fr; }
}


.quiz-options { display: grid; gap: 0.85rem; }
.quiz-option { display: flex; gap: 0.75rem; align-items: flex-start; padding: 0.95rem 1rem; border: 1px solid rgba(255,255,255,0.12); border-radius: 14px; background: rgba(255,255,255,0.03); cursor: pointer; }
.quiz-option input { margin-top: 0.2rem; }
.stacked-actions { display: flex; flex-direction: column; gap: 0.5rem; align-items: stretch; }
.quiz-review-item { align-items: flex-start; gap: 1rem; }
.pill-success { background: rgba(73, 178, 120, 0.2); color: #aef1c6; }
.pill-danger { background: rgba(214, 93, 93, 0.2); color: #ffd0d0; }

.stats-grid {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 20px;
}
.stat-card {
    text-align: left;
}
.stat-label {
    display: block;
    font-size: 0.84rem;
    text-transform: uppercase;
    color: var(--muted);
    margin-bottom: 8px;
}
.stat-number {
    display: block;
    font-size: 2rem;
    margin-bottom: 8px;
}
.review-queue {
    display: grid;
    gap: 16px;
}
.review-item {
    display: grid;
    gap: 14px;
    padding: 18px;
    border-radius: 18px;
    background: rgba(255,255,255,0.03);
    border: 1px solid rgba(255,255,255,0.08);
}
.review-item h4 {
    margin: 10px 0 8px;
    font-size: 1.2rem;
}
.mini-metrics {
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 10px;
    margin: 0;
}
.mini-metrics div {
    padding: 12px;
    border-radius: 14px;
    background: rgba(255,255,255,0.03);
    border: 1px solid rgba(255,255,255,0.08);
}
.mini-metrics dt {
    font-size: 0.74rem;
    text-transform: uppercase;
    color: var(--muted);
    margin-bottom: 6px;
}
.mini-metrics dd { margin: 0; font-weight: 700; }
.spaced-metrics { margin-top: 18px; }
.compact-actions { margin-top: 0; }
.chips {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-top: 16px;
}
.chip {
    padding: 8px 12px;
    border-radius: 999px;
    border: 1px solid rgba(255,255,255,0.10);
    background: rgba(255,255,255,0.04);
    color: var(--muted);
}
@media (max-width: 920px) {
    .stats-grid,
    .grid.two-cols,
    .hero,
    .feature-grid,
    .setup-grid,
    .mini-metrics {
        grid-template-columns: 1fr;
    }
}


.pwa-stack {
    display: grid;
    gap: 12px;
}
.pwa-banner {
    padding: 14px 16px;
    border-radius: 16px;
    border: 1px solid var(--line);
    background: rgba(255,255,255,0.04);
    color: var(--text);
    line-height: 1.6;
}
.pwa-banner.offline {
    background: rgba(245, 196, 81, 0.12);
    border-color: rgba(245, 196, 81, 0.25);
    color: #ffe9a8;
}
.pwa-banner.update {
    background: rgba(124, 92, 255, 0.14);
    border-color: rgba(124, 92, 255, 0.32);
    color: #e4dcff;
}
.inline-action {
    margin-left: 10px;
    appearance: none;
    border: 0;
    background: var(--primary);
    color: #fff;
    border-radius: 999px;
    padding: 9px 14px;
    font-weight: 700;
    cursor: pointer;
}
.nav-install {
    background: rgba(124, 92, 255, 0.16);
    border-color: rgba(124, 92, 255, 0.35);
}
@media (max-width: 720px) {
    .inline-action {
        margin: 12px 0 0;
        display: inline-flex;
    }
}