:root {
    --font-body: "Manrope", "Segoe UI", "Helvetica Neue", sans-serif;
    --font-mono: "IBM Plex Mono", "Cascadia Code", "Consolas", monospace;

    --bg-canvas: #f3f5f8;
    --bg-surface: #ffffff;
    --bg-surface-soft: #f8fafc;
    --bg-hover: #f0f4ff;
    --bg-focus: #e8efff;

    --text-primary: #1f2937;
    --text-secondary: #4b5563;
    --text-muted: #6b7280;

    --border-soft: #e5e7eb;
    --border-strong: #d1d5db;

    --accent: #2563eb;
    --accent-strong: #1d4ed8;
    --accent-soft: #dbeafe;
    --accent-contrast: #ffffff;

    --ok-bg: #eaf9ef;
    --ok-text: #166534;
    --warn-bg: #fff6e8;
    --warn-text: #9a5600;
    --bad-bg: #fff0f0;
    --bad-text: #a11717;

    --pill-stable-bg: #dcfce7;
    --pill-stable-text: #14532d;
    --pill-candidate-bg: #dbeafe;
    --pill-candidate-text: #1e3a8a;
    --pill-active-bg: #ccfbf1;
    --pill-active-text: #134e4a;
    --pill-partial-bg: #ffedd5;
    --pill-partial-text: #9a3412;
    --pill-empty-bg: #e2e8f0;
    --pill-empty-text: #334155;

    --shadow-sm: 0 2px 8px rgba(15, 23, 42, 0.06);
    --shadow-md: 0 10px 30px rgba(15, 23, 42, 0.08);

    --radius-sm: 10px;
    --radius-md: 14px;
    --radius-lg: 18px;
    --radius-pill: 999px;

    --space-1: 4px;
    --space-2: 8px;
    --space-3: 12px;
    --space-4: 16px;
    --space-5: 20px;
    --space-6: 24px;
    --space-7: 32px;
}

.tv-shortcut-card {
    margin-top: 14px;
    display: inline-flex;
    gap: 10px;
    align-items: center;
    flex-wrap: wrap;
    padding: 10px 14px;
    border-radius: var(--radius-sm);
    background: var(--accent-soft);
    color: var(--text-primary);
}

.tv-shortcut-card a {
    font-family: var(--font-mono);
    color: var(--accent-strong);
    text-decoration: none;
    word-break: break-all;
}

.tv-client-container {
    max-width: 760px;
}

.tv-hero {
    margin-bottom: 20px;
}

.tv-kicker {
    display: inline-block;
    margin-bottom: 10px;
    padding: 6px 10px;
    border-radius: var(--radius-pill);
    background: var(--accent-soft);
    color: var(--accent-strong);
    font-size: 12px;
    font-weight: 800;
    letter-spacing: 0.08em;
    text-transform: uppercase;
}

.tv-subtitle {
    max-width: 580px;
    color: var(--text-secondary);
    font-size: 16px;
}

.tv-key-card {
    margin-top: 0;
}

.tv-userline {
    margin-bottom: 16px;
    color: var(--text-secondary);
}

.tv-note {
    margin-bottom: 18px;
    color: var(--text-secondary);
}

.tv-link-box {
    width: 100%;
    min-height: 220px;
    padding: 16px;
    border: 1px solid var(--border-soft);
    border-radius: var(--radius-md);
    background: var(--bg-surface-soft);
    color: var(--text-primary);
    font: 500 14px/1.55 var(--font-mono);
    resize: vertical;
    word-break: break-all;
}

.tv-actions {
    display: flex;
    gap: 12px;
    flex-wrap: wrap;
    margin-top: 18px;
}

.tv-copy-btn,
.tv-open-btn {
    min-width: 190px;
    justify-content: center;
}

.tv-help-card {
    margin-top: 20px;
    padding: 24px;
    border-radius: var(--radius-lg);
    background: var(--bg-surface);
    border: 1px solid var(--border-soft);
    box-shadow: var(--shadow-sm);
}

.tv-help-card h4 {
    margin-bottom: 12px;
    font-size: 18px;
}

.tv-steps {
    margin: 0 0 16px 20px;
    color: var(--text-secondary);
}

.tv-steps li + li {
    margin-top: 6px;
}

.tv-meta-row {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
    margin-top: 10px;
    color: var(--text-secondary);
}

.tv-meta-row a {
    color: var(--accent-strong);
    text-decoration: none;
    word-break: break-all;
}

@media (max-width: 720px) {
    .tv-link-box {
        min-height: 260px;
        font-size: 13px;
    }
}

:root[data-theme="dark"],
html[data-theme="dark"],
body[data-theme="dark"],
[data-theme="dark"] {
    --bg-canvas: #0b1220;
    --bg-surface: #111827;
    --bg-surface-soft: #172033;
    --bg-hover: #1f2a40;
    --bg-focus: #25344f;

    --text-primary: #e5e7eb;
    --text-secondary: #c1c9d6;
    --text-muted: #93a2ba;

    --border-soft: #243248;
    --border-strong: #2f405a;

    --accent: #60a5fa;
    --accent-strong: #3b82f6;
    --accent-soft: #1e3a8a;
    --accent-contrast: #0b1220;

    --ok-bg: #173125;
    --ok-text: #9fe4b8;
    --warn-bg: #3b2b11;
    --warn-text: #f3c989;
    --bad-bg: #3a1718;
    --bad-text: #ffb5b8;

    --pill-stable-bg: #173125;
    --pill-stable-text: #b8f2cf;
    --pill-candidate-bg: #1e3a8a;
    --pill-candidate-text: #bfdbfe;
    --pill-active-bg: #163734;
    --pill-active-text: #9ce7dd;
    --pill-partial-bg: #3b2b11;
    --pill-partial-text: #ffd8a8;
    --pill-empty-bg: #27364e;
    --pill-empty-text: #d1deef;

    --shadow-sm: 0 3px 12px rgba(2, 8, 23, 0.45);
    --shadow-md: 0 16px 32px rgba(2, 8, 23, 0.5);
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: var(--font-body);
    background: radial-gradient(1200px 600px at 12% -10%, #eaf2ff 0%, transparent 60%),
        radial-gradient(1000px 500px at 90% -15%, #f2f7ff 0%, transparent 65%),
        var(--bg-canvas);
    color: var(--text-primary);
    min-height: 100vh;
    line-height: 1.5;
}

[data-theme="dark"] body {
    background: radial-gradient(1200px 600px at 12% -10%, #112036 0%, transparent 60%),
        radial-gradient(1000px 500px at 90% -15%, #1b2740 0%, transparent 65%),
        var(--bg-canvas);
}

.container {
    width: 100%;
    max-width: 420px;
    margin: 40px auto;
    padding: 24px;
    background: var(--bg-surface);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    border: 1px solid var(--border-soft);
}

header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--space-7);
}

.title {
    font-size: clamp(30px, 4vw, 42px);
    line-height: 1.15;
    font-weight: 800;
    color: #0f172a;
    letter-spacing: -0.02em;
}

.score-container {
    background: var(--bg-surface-soft);
    border: 1px solid var(--border-soft);
    padding: 10px 18px;
    border-radius: var(--radius-sm);
    text-align: center;
}

.score-label {
    font-size: 12px;
    font-weight: 600;
    color: var(--text-muted);
}

#score {
    font-size: 24px;
    line-height: 1.15;
    font-weight: 800;
    color: var(--text-primary);
}

.game-container {
    position: relative;
    width: 320px;
    height: 320px;
    margin: 0 auto var(--space-7);
    background: #d4dce8;
    border-radius: var(--radius-sm);
    padding: 10px;
}

.grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    grid-template-rows: repeat(4, 1fr);
    gap: 10px;
    width: 100%;
    height: 100%;
}

.cell {
    width: 65px;
    height: 65px;
    background: rgba(255, 255, 255, 0.5);
    border-radius: 8px;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 24px;
    font-weight: 800;
    color: #243244;
    transition: all 0.15s ease-in-out;
}

.cell-2 { background: #f7f8fa; color: #273549; }
.cell-4 { background: #eef2f8; color: #273549; }
.cell-8 { background: #dbe7ff; color: #1e3a8a; }
.cell-16 { background: #c8dcff; color: #1e3a8a; }
.cell-32 { background: #b3d0ff; color: #1e3a8a; }
.cell-64 { background: #98bfff; color: #173478; }
.cell-128 { background: #84b0ff; color: #123063; font-size: 20px; }
.cell-256 { background: #6fa1ff; color: #10294f; font-size: 20px; }
.cell-512 { background: #5e93f8; color: #fff; font-size: 20px; }
.cell-1024 { background: #4f84ea; color: #fff; font-size: 16px; }
.cell-2048 { background: #3f72d8; color: #fff; font-size: 16px; box-shadow: 0 0 14px rgba(37, 99, 235, 0.35); }

.controls {
    text-align: center;
}

#new-game {
    background: var(--accent);
    color: var(--accent-contrast);
    border: none;
    padding: 12px 24px;
    border-radius: var(--radius-sm);
    font-size: 14px;
    font-weight: 700;
    cursor: pointer;
    transition: transform 0.2s, background-color 0.2s;
}

#new-game:hover {
    background: var(--accent-strong);
    transform: translateY(-1px);
}

.instructions {
    margin-top: var(--space-3);
    font-size: 14px;
    color: var(--text-muted);
}

/* Client Page Styles */
.client-container {
    max-width: 720px;
    margin: 0 auto;
    padding: 40px 20px;
}

.key-card {
    background: var(--bg-surface);
    border: 1px solid var(--border-soft);
    border-radius: var(--radius-lg);
    padding: 30px;
    margin-top: 20px;
    box-shadow: var(--shadow-sm);
}

.key-title {
    font-size: 24px;
    font-weight: 700;
    margin-bottom: 10px;
    color: var(--text-primary);
}

.key-value {
    background: var(--bg-surface-soft);
    padding: 15px;
    border-radius: var(--radius-sm);
    font-family: var(--font-mono);
    word-break: break-all;
    font-size: 13px;
    line-height: 1.6;
    margin: 15px 0;
    border: 1px solid var(--border-soft);
    color: #1e293b;
}

.copy-btn {
    width: 100%;
    padding: 12px;
    background: var(--accent);
    color: var(--accent-contrast);
    border: none;
    border-radius: var(--radius-sm);
    font-size: 14px;
    font-weight: 700;
    cursor: pointer;
    transition: background-color 0.2s;
}

.copy-btn:hover {
    background: var(--accent-strong);
}

.admin-shell {
    width: 100%;
    max-width: 1280px;
    margin: 0 auto;
    padding: 28px 24px 80px;
}

.admin-stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--space-4);
    margin-bottom: var(--space-5);
}

.admin-stat-card {
    background: var(--bg-surface);
    border: 1px solid var(--border-soft);
    border-radius: var(--radius-md);
    padding: 18px 20px;
    box-shadow: var(--shadow-sm);
}

.admin-stat-value {
    font-size: 32px;
    line-height: 1.1;
    font-weight: 800;
    color: #0f172a;
}

.admin-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    gap: var(--space-4);
    margin-bottom: var(--space-6);
}

.admin-header-actions {
    display: flex;
    align-items: center;
    gap: 10px;
}

.theme-toggle {
    border: 1px solid var(--border-strong);
    background: var(--bg-surface);
    color: var(--text-primary);
    border-radius: 50%;
    width: 40px;
    height: 40px;
    padding: 0;
    font-size: 14px;
    font-weight: 700;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0;
    line-height: 1;
    box-shadow: var(--shadow-sm);
}

.theme-toggle:hover {
    background: var(--bg-hover);
}

.theme-toggle .theme-icon {
    font-size: 18px;
}

.theme-toggle .theme-label {
    display: none;
}

.admin-subtitle {
    color: var(--text-secondary);
    max-width: 900px;
    line-height: 1.6;
}

.admin-panel {
    background: var(--bg-surface);
    border: 1px solid var(--border-soft);
    border-radius: var(--radius-lg);
    padding: var(--space-6);
    margin-top: var(--space-5);
    box-shadow: var(--shadow-sm);
}

.admin-search {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-3);
    margin-bottom: var(--space-4);
}

.admin-search-input {
    flex: 1 1 300px;
    min-width: 220px;
    padding: 12px 14px;
    border-radius: var(--radius-sm);
    border: 1px solid var(--border-strong);
    background: #ffffff;
    color: var(--text-primary);
    font-family: inherit;
    font-size: 14px;
}

.admin-search-input:focus {
    outline: none;
    border-color: #93c5fd;
    box-shadow: 0 0 0 3px var(--bg-focus);
}

.admin-search-input::placeholder {
    color: #94a3b8;
}

.admin-section-title {
    font-size: clamp(21px, 2.4vw, 26px);
    font-weight: 800;
    color: #0f172a;
    margin-bottom: var(--space-4);
    letter-spacing: -0.01em;
}

[data-theme="dark"] .title,
[data-theme="dark"] .admin-section-title,
[data-theme="dark"] .admin-user-name,
[data-theme="dark"] .key-title {
    color: #f8fafc;
}

[data-theme="dark"] .admin-backlink {
    color: #b9c7dd;
}

[data-theme="dark"] .admin-backlink:hover {
    color: #f8fafc;
}

[data-theme="dark"] .admin-link {
    color: #93c5fd;
}

[data-theme="dark"] .admin-btn-secondary {
    background: #1d2739;
    color: #e5e7eb;
    border-color: #32425e;
}

[data-theme="dark"] .admin-btn-secondary:hover {
    background: #26324a;
}

[data-theme="dark"] .admin-btn-ghost {
    background: #172033;
    color: #dbe4f1;
    border-color: #2c3b56;
}

[data-theme="dark"] .admin-btn-ghost:hover {
    background: #1f2a40;
}

[data-theme="dark"] .admin-btn-link {
    background: #1f2a40;
    color: #9ec5ff;
    border-color: #36517a;
}

[data-theme="dark"] .admin-btn-link:hover {
    background: #25344f;
}

.admin-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--space-4);
}

.admin-card,
.admin-user-card {
    background: var(--bg-surface-soft);
    border: 1px solid var(--border-soft);
    border-radius: var(--radius-md);
    padding: 18px;
}

.admin-card-label,
.admin-routes-title {
    font-size: 13px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.04em;
    color: var(--text-muted);
    margin-bottom: var(--space-2);
}

.admin-link {
    font-family: var(--font-mono);
    font-size: 12px;
    line-height: 1.7;
    word-break: break-all;
    color: #1d4ed8;
}

.admin-stack {
    display: grid;
    gap: var(--space-4);
}

.admin-user-top,
.admin-route-row,
.admin-event-row {
    display: flex;
    justify-content: space-between;
    gap: var(--space-4);
}

.admin-user-top {
    align-items: flex-start;
}

.admin-user-name {
    font-size: 22px;
    line-height: 1.2;
    font-weight: 800;
    margin-bottom: var(--space-2);
    color: #0f172a;
}

.admin-user-meta {
    color: var(--text-secondary);
    font-size: 13px;
    line-height: 1.6;
    word-break: break-word;
}

.admin-routes {
    margin-top: var(--space-4);
    display: grid;
    gap: var(--space-3);
}

.admin-error {
    color: var(--bad-text);
    font-size: 13px;
    line-height: 1.6;
    background: var(--bad-bg);
    border: 1px solid #fecaca;
    border-radius: 10px;
    padding: 8px 10px;
}

.status-pill {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 92px;
    padding: 7px 12px;
    border-radius: var(--radius-pill);
    font-size: 12px;
    font-weight: 700;
    letter-spacing: 0.02em;
}

.status-ok {
    background: var(--ok-bg);
    color: var(--ok-text);
}

.status-warn {
    background: var(--warn-bg);
    color: var(--warn-text);
}

.status-bad {
    background: var(--bad-bg);
    color: var(--bad-text);
}

.admin-events {
    display: grid;
    gap: var(--space-3);
}

.admin-event-row {
    align-items: flex-start;
    background: var(--bg-surface-soft);
    border: 1px solid var(--border-soft);
    border-radius: var(--radius-sm);
    padding: 14px 16px;
}

.admin-event-side {
    text-align: right;
}

.admin-empty {
    color: var(--text-muted);
    font-size: 14px;
}

.admin-status-card {
    min-height: 120px;
}

.admin-refresh-panel {
    padding-top: 20px;
    padding-bottom: 20px;
}

.admin-statusbar-panel {
    padding-top: 14px;
    padding-bottom: 14px;
}

.admin-statusbar {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    align-items: center;
}

.admin-refresh-row {
    display: flex;
    justify-content: space-between;
    gap: var(--space-4);
    align-items: center;
    flex-wrap: wrap;
}

.admin-backlink {
    display: inline-block;
    margin-bottom: 12px;
    color: #475569;
    text-decoration: none;
    font-size: 14px;
    font-weight: 600;
}

.admin-backlink:hover {
    color: #0f172a;
}

.admin-banner {
    border-radius: var(--radius-sm);
    padding: 14px 18px;
    margin-bottom: 16px;
    font-size: 14px;
    border: 1px solid var(--border-soft);
    transition: opacity 0.3s ease, transform 0.3s ease;
}

.admin-banner-success {
    background: var(--ok-bg);
    color: var(--ok-text);
    border-color: #bbf7d0;
}

.admin-banner-error {
    background: var(--bad-bg);
    color: var(--bad-text);
    border-color: #fecaca;
}

.admin-actions {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-2);
    margin-top: var(--space-2);
}

.admin-actions form {
    margin: 0;
}

.admin-inline-form {
    display: flex;
    gap: var(--space-2);
    flex-wrap: wrap;
    align-items: center;
}

.admin-confirm-form {
    display: grid;
    gap: var(--space-2);
}

.admin-confirm-check {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    font-size: 13px;
    color: var(--text-secondary);
}

.admin-confirm-check input {
    accent-color: var(--accent);
}

.admin-btn {
    border: 1px solid transparent;
    border-radius: var(--radius-sm);
    padding: 10px 14px;
    font-family: inherit;
    font-size: 13px;
    line-height: 1.2;
    font-weight: 700;
    cursor: pointer;
    transition: transform 0.12s ease, background-color 0.2s ease, border-color 0.2s ease;
}

.admin-btn:hover {
    transform: translateY(-1px);
}

.admin-btn-primary {
    background: var(--accent);
    color: var(--accent-contrast);
    border-color: var(--accent-strong);
}

.admin-btn-primary:hover {
    background: var(--accent-strong);
    color: #ffffff;
}

.admin-btn-secondary {
    background: #f1f5f9;
    color: #0f172a;
    border-color: #dbe1ea;
}

.admin-btn-secondary:hover {
    background: #e8eef8;
}

.admin-btn-ghost {
    background: #ffffff;
    color: #374151;
    border-color: #d6dee9;
}

.admin-btn-ghost:hover {
    background: #f8fbff;
}

.admin-btn-danger {
    background: #fff3f3;
    color: #a11717;
    border-color: #fecaca;
}

.admin-btn-danger:hover {
    background: #ffe8e8;
}

.admin-warning-card {
    margin-bottom: 16px;
    padding: 16px 18px;
    border-radius: var(--radius-md);
    background: #fffaf0;
    border: 1px solid #fde68a;
    display: grid;
    gap: 8px;
}

.admin-warning-title {
    font-size: 14px;
    font-weight: 800;
    color: #92400e;
    text-transform: uppercase;
    letter-spacing: 0.04em;
}

.admin-warning-inline {
    padding: 12px 14px;
    border-radius: var(--radius-sm);
    background: #f8fafc;
    border: 1px solid #e2e8f0;
    color: #334155;
    font-size: 13px;
}

.admin-checklist {
    display: grid;
    gap: var(--space-3);
}

.admin-check-row {
    padding: 14px 16px;
    border-radius: var(--radius-sm);
    background: var(--bg-surface-soft);
    border: 1px solid var(--border-soft);
}

.admin-check-main {
    display: flex;
    gap: 14px;
    align-items: flex-start;
}

.admin-check-label {
    font-size: 14px;
    font-weight: 700;
    color: #0f172a;
    margin-bottom: 4px;
}

.admin-rollout-footer {
    margin-top: 14px;
    padding: 14px 16px;
    border-radius: var(--radius-sm);
    font-size: 14px;
    font-weight: 700;
}

.admin-rollout-ready {
    background: var(--ok-bg);
    color: var(--ok-text);
    border: 1px solid #bbf7d0;
}

.admin-rollout-blocked {
    background: var(--warn-bg);
    color: var(--warn-text);
    border: 1px solid #fde68a;
}

.admin-btn-link {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    text-decoration: none;
    background: var(--bg-hover);
    color: var(--accent-strong);
    border-color: #c7dcff;
}

.admin-btn-link:hover {
    background: var(--bg-focus);
}

.admin-mode-row {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin-top: var(--space-3);
}

.mode-pill {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius-pill);
    padding: 6px 10px;
    font-size: 12px;
    font-weight: 700;
    letter-spacing: 0.03em;
    border: 1px solid color-mix(in srgb, currentColor 18%, transparent);
}

.mode-stable {
    background: var(--pill-stable-bg);
    color: var(--pill-stable-text);
}

.mode-candidate {
    background: var(--pill-candidate-bg);
    color: var(--pill-candidate-text);
}

.mode-active {
    background: var(--pill-active-bg);
    color: var(--pill-active-text);
}

.mode-partial {
    background: var(--pill-partial-bg);
    color: var(--pill-partial-text);
}

.mode-empty {
    background: var(--pill-empty-bg);
    color: var(--pill-empty-text);
}

.admin-compact-group {
    margin: 0;
}

.admin-compact-summary {
    cursor: pointer;
    list-style: none;
    font-size: 18px;
    font-weight: 700;
    color: #0f172a;
    display: flex;
    align-items: center;
    gap: 10px;
}

.admin-compact-summary::-webkit-details-marker {
    display: none;
}

.admin-compact-summary::before {
    content: "+";
    width: 24px;
    height: 24px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border-radius: 999px;
    background: var(--bg-hover);
    color: var(--accent-strong);
    font-size: 16px;
    line-height: 1;
}

.admin-compact-group[open] .admin-compact-summary::before {
    content: "-";
}

@media (max-width: 900px) {
    .admin-header {
        flex-direction: column;
        align-items: flex-start;
    }

    .admin-shell {
        padding: 20px 14px 40px;
    }

    .admin-panel {
        padding: 16px;
        margin-top: 14px;
    }

    .admin-grid {
        grid-template-columns: 1fr;
        gap: 12px;
    }

    .admin-stats-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
        gap: 10px;
    }

    .admin-stat-value {
        font-size: 26px;
    }

    .admin-user-top,
    .admin-route-row,
    .admin-event-row {
        flex-direction: column;
        align-items: flex-start;
        gap: 10px;
    }

    .admin-event-side {
        text-align: left;
    }

    .admin-actions {
        gap: 8px;
    }
}