:root,
[data-theme="dark"] {
	--bg: #0f1419;
	--surface: #1a2332;
	--surface2: #243044;
	--border: #2d3a4f;
	--text: #e8eef7;
	--muted: #8b9bb4;
	--accent: #3b82f6;
	--accent-hover: #2563eb;
	--ok: #22c55e;
	--ok-bg: rgba(34, 197, 94, 0.12);
	--bad: #ef4444;
	--bad-bg: rgba(239, 68, 68, 0.12);
	--warn: #f59e0b;
	--radius: 12px;
	--font: "Segoe UI", system-ui, -apple-system, sans-serif;
}

[data-theme="light"] {
	--bg: #f1f5f9;
	--surface: #ffffff;
	--surface2: #e2e8f0;
	--border: #cbd5e1;
	--text: #0f172a;
	--muted: #64748b;
	--accent: #2563eb;
	--accent-hover: #1d4ed8;
	--ok: #16a34a;
	--ok-bg: rgba(22, 163, 74, 0.12);
	--bad: #dc2626;
	--bad-bg: rgba(220, 38, 38, 0.1);
	--warn: #d97706;
}

* {
	box-sizing: border-box;
}

body {
	margin: 0;
	min-height: 100vh;
	font-family: var(--font);
	background: radial-gradient(ellipse at top, #1a2740 0%, var(--bg) 55%);
	color: var(--text);
	line-height: 1.5;
}

a {
	color: var(--accent);
	text-decoration: none;
}

a:hover {
	text-decoration: underline;
}

.wrap {
	max-width: 760px;
	margin: 0 auto;
	padding: 1.5rem 1rem 3rem;
}

.mode-bar {
	display: flex;
	flex-wrap: wrap;
	gap: 0.4rem;
	margin-bottom: 1rem;
}

.mode-bar button {
	background: transparent;
	border: 1px solid var(--border);
	color: var(--muted);
	font-weight: 600;
}

.mode-bar button.active {
	background: var(--accent);
	border-color: var(--accent);
	color: #fff;
}

.mode-bar button:hover:not(.active) {
	background: var(--surface2);
}

.feed {
	display: flex;
	flex-direction: column;
	gap: 1rem;
}

.ad-slot {
	display: block;
	width: 100%;
	min-height: 90px;
	overflow: hidden;
	text-align: center;
}

.quiz-card .explanation-body {
	white-space: pre-wrap;
	margin: 0;
}

.badge.tag {
	color: #c4b5fd;
	border-color: #4c1d95;
	background: rgba(139, 92, 246, 0.15);
	text-transform: none;
	letter-spacing: 0;
	font-weight: 600;
}

.search-field {
	flex: 2;
	min-width: 180px;
}

.tag-picker {
	display: flex;
	flex-wrap: wrap;
	gap: 0.5rem 0.85rem;
	padding: 0.65rem 0.75rem;
	border: 1px dashed var(--border);
	border-radius: 10px;
	background: var(--surface2);
}

.tag-picker label {
	display: flex;
	align-items: center;
	gap: 0.35rem;
	font-size: 0.85rem;
	color: var(--text);
	cursor: pointer;
}

.btn-like:disabled {
	opacity: 0.75;
}

header.app-header {
	display: flex;
	align-items: center;
	justify-content: space-between;
	gap: 1rem;
	margin-bottom: 1.75rem;
	flex-wrap: wrap;
}

header.app-header h1 {
	margin: 0;
	font-size: 1.35rem;
	font-weight: 700;
	letter-spacing: -0.02em;
}

header.app-header .sub {
	color: var(--muted);
	font-size: 0.9rem;
	margin: 0.2rem 0 0;
}

.card {
	background: var(--surface);
	border: 1px solid var(--border);
	border-radius: var(--radius);
	padding: 1.25rem 1.35rem;
	box-shadow: 0 8px 32px rgba(0, 0, 0, 0.25);
}

.toolbar {
	display: flex;
	flex-wrap: wrap;
	gap: 0.75rem;
	align-items: end;
	margin-bottom: 1rem;
}

label.field {
	display: flex;
	flex-direction: column;
	gap: 0.35rem;
	font-size: 0.8rem;
	color: var(--muted);
	flex: 1;
	min-width: 140px;
}

input,
select,
textarea,
button {
	font: inherit;
}

input,
select,
textarea {
	background: var(--surface2);
	border: 1px solid var(--border);
	color: var(--text);
	border-radius: 8px;
	padding: 0.55rem 0.7rem;
	outline: none;
}

input:focus,
select:focus,
textarea:focus {
	border-color: var(--accent);
}

button,
.btn {
	display: inline-flex;
	align-items: center;
	justify-content: center;
	gap: 0.4rem;
	background: var(--accent);
	color: #fff;
	border: none;
	border-radius: 8px;
	padding: 0.55rem 1rem;
	cursor: pointer;
	font-weight: 600;
	font-size: 0.95rem;
}

button:hover,
.btn:hover {
	background: var(--accent-hover);
}

button:disabled {
	opacity: 0.5;
	cursor: not-allowed;
}

button.secondary,
.btn.secondary {
	background: var(--surface2);
	border: 1px solid var(--border);
	color: var(--text);
}

button.secondary:hover,
.btn.secondary:hover {
	background: var(--border);
}

button.danger {
	background: var(--bad);
}

button.danger:hover {
	background: #dc2626;
}

.badge {
	display: inline-block;
	font-size: 0.72rem;
	font-weight: 700;
	text-transform: uppercase;
	letter-spacing: 0.04em;
	padding: 0.2rem 0.5rem;
	border-radius: 999px;
	background: var(--surface2);
	color: var(--muted);
	border: 1px solid var(--border);
}

.badge.cat {
	color: #93c5fd;
	border-color: #1e3a5f;
	background: rgba(59, 130, 246, 0.12);
}

.meta-row {
	display: flex;
	flex-wrap: wrap;
	gap: 0.5rem;
	margin-bottom: 0.85rem;
}

.prompt {
	font-size: 1.15rem;
	font-weight: 600;
	margin: 0 0 1rem;
	white-space: pre-wrap;
}

.options {
	display: flex;
	flex-direction: column;
	gap: 0.55rem;
	margin-bottom: 1rem;
}

.option {
	display: flex;
	align-items: flex-start;
	gap: 0.65rem;
	padding: 0.75rem 0.9rem;
	border-radius: 10px;
	border: 1px solid var(--border);
	background: var(--surface2);
	cursor: pointer;
	transition: border-color 0.15s, background 0.15s;
}

.option:hover {
	border-color: #4b5d78;
}

.option.selected {
	border-color: var(--accent);
	background: rgba(59, 130, 246, 0.1);
}

.option.correct {
	border-color: var(--ok);
	background: var(--ok-bg);
}

.option.incorrect {
	border-color: var(--bad);
	background: var(--bad-bg);
}

.option input {
	margin-top: 0.2rem;
	accent-color: var(--accent);
}

.option .label {
	font-weight: 700;
	color: var(--muted);
	min-width: 1.2rem;
}

.option .body {
	flex: 1;
	white-space: pre-wrap;
}

.pagination {
	display: flex;
	flex-wrap: wrap;
	align-items: center;
	justify-content: space-between;
	gap: 0.75rem;
	margin-top: 0.85rem;
	font-size: 0.9rem;
	color: var(--muted);
}

.pagination .pager {
	display: flex;
	align-items: center;
	gap: 0.5rem;
}

.option-row textarea[name="opt_body"] {
	min-height: 2.4rem;
	resize: vertical;
}

.actions {
	display: flex;
	flex-wrap: wrap;
	gap: 0.6rem;
}

.explanation {
	margin-top: 1rem;
	padding: 0.9rem 1rem;
	border-radius: 10px;
	border: 1px solid var(--border);
	background: rgba(255, 255, 255, 0.03);
}

.explanation h3 {
	margin: 0 0 0.4rem;
	font-size: 0.85rem;
	text-transform: uppercase;
	letter-spacing: 0.04em;
	color: var(--muted);
}

.explanation.ok {
	border-color: rgba(34, 197, 94, 0.4);
}

.explanation.bad {
	border-color: rgba(239, 68, 68, 0.4);
}

.result-banner {
	font-weight: 700;
	margin-bottom: 0.35rem;
}

.result-banner.ok {
	color: var(--ok);
}

.result-banner.bad {
	color: var(--bad);
}

.empty,
.error,
.loading {
	text-align: center;
	color: var(--muted);
	padding: 2rem 1rem;
}

.error {
	color: var(--bad);
}

.hidden {
	display: none !important;
}

footer.site-footer {
	margin-top: 2rem;
	text-align: center;
	color: var(--muted);
	font-size: 0.85rem;
	padding: 0 1rem 2rem;
}

.footer-nav {
	display: flex;
	flex-wrap: wrap;
	justify-content: center;
	gap: 0.35rem 0.85rem;
	margin-bottom: 0.5rem;
}

.footer-nav a {
	color: var(--muted);
}

.footer-nav a:hover {
	color: var(--accent);
}

.footer-note {
	margin: 0;
	font-size: 0.8rem;
}

.seo-block,
.seo-article {
	margin-top: 1.5rem;
}

.seo-heading {
	font-size: 1.15rem;
	margin: 0 0 0.65rem;
}

.seo-sub {
	font-size: 0.95rem;
	margin: 1rem 0 0.4rem;
	color: var(--muted);
	text-transform: uppercase;
	letter-spacing: 0.04em;
	font-weight: 700;
}

.seo-prompt {
	font-size: 1.15rem;
	font-weight: 650;
	line-height: 1.45;
	margin: 0.5rem 0 0.75rem;
}

.seo-lead {
	margin: 0 0 1rem;
	font-size: 0.9rem;
}

.seo-options {
	margin: 0 0 1rem;
	padding-left: 1.25rem;
}

.seo-option {
	margin: 0.35rem 0;
}

.seo-option .label {
	font-weight: 700;
	color: var(--accent);
	margin-right: 0.35rem;
}

.seo-notes {
	margin-top: 0.5rem;
}

.seo-q-list {
	list-style: none;
	margin: 0;
	padding: 0;
}

.seo-q-list li {
	border-top: 1px solid var(--border);
	padding: 0.65rem 0;
	display: flex;
	flex-direction: column;
	gap: 0.15rem;
}

.seo-q-list li:last-child {
	border-bottom: 1px solid var(--border);
}

.seo-q-meta {
	font-size: 0.8rem;
	color: var(--muted);
}

.seo-cat-grid {
	list-style: none;
	margin: 0 0 1.25rem;
	padding: 0;
	display: grid;
	grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
	gap: 0.6rem;
}

.seo-cat-grid a {
	display: flex;
	flex-direction: column;
	gap: 0.2rem;
	padding: 0.75rem 0.85rem;
	background: var(--surface);
	border: 1px solid var(--border);
	border-radius: var(--radius);
	color: var(--text);
	text-decoration: none;
}

.seo-cat-grid a:hover {
	border-color: var(--accent);
	text-decoration: none;
}

.seo-cat-grid span {
	font-size: 0.8rem;
	color: var(--muted);
}

.seo-more {
	margin-top: 1rem;
}

.seo-related {
	margin-top: 1.25rem;
}

.static-page {
	padding: 1.25rem 1.35rem 1.5rem;
}

.static-page h1 {
	margin: 0 0 0.75rem;
	font-size: 1.5rem;
}

.static-page h2 {
	margin: 1.35rem 0 0.5rem;
	font-size: 1.1rem;
}

.static-page p,
.static-page li {
	color: var(--text);
}

.static-page ul {
	padding-left: 1.25rem;
}

.home-intro p {
	margin: 0 0 0.75rem;
}

.muted {
	color: var(--muted);
}

/* Admin extras */
.admin-nav {
	display: flex;
	flex-wrap: wrap;
	gap: 0.4rem;
	margin-bottom: 1.25rem;
}

.admin-nav button {
	background: transparent;
	border: 1px solid var(--border);
	color: var(--muted);
	font-weight: 600;
}

.admin-nav button.active {
	background: var(--accent);
	border-color: var(--accent);
	color: #fff;
}

.stats-grid {
	display: grid;
	grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
	gap: 0.75rem;
	margin-bottom: 1.25rem;
}

.stat {
	background: var(--surface2);
	border: 1px solid var(--border);
	border-radius: 10px;
	padding: 0.85rem;
	text-align: center;
}

.stat .n {
	font-size: 1.4rem;
	font-weight: 700;
}

.stat .l {
	font-size: 0.75rem;
	color: var(--muted);
	text-transform: uppercase;
	letter-spacing: 0.03em;
}

table {
	width: 100%;
	border-collapse: collapse;
	font-size: 0.9rem;
}

th,
td {
	text-align: left;
	padding: 0.55rem 0.45rem;
	border-bottom: 1px solid var(--border);
	vertical-align: top;
}

th {
	color: var(--muted);
	font-size: 0.75rem;
	text-transform: uppercase;
	letter-spacing: 0.03em;
}

.table-wrap {
	overflow-x: auto;
}

th.sortable {
	cursor: pointer;
	user-select: none;
	white-space: nowrap;
}

th.sortable:hover {
	color: var(--text);
}

th.sortable.sort-asc::after,
th.sortable.sort-desc::after {
	margin-left: 0.25rem;
	opacity: 0.85;
}

th.sortable.sort-asc::after {
	content: "↑";
}

th.sortable.sort-desc::after {
	content: "↓";
}

.form-grid {
	display: flex;
	flex-direction: column;
	gap: 0.85rem;
}

.form-row {
	display: flex;
	flex-wrap: wrap;
	gap: 0.75rem;
}

.form-row > * {
	flex: 1;
	min-width: 140px;
}

.option-editor {
	border: 1px dashed var(--border);
	border-radius: 10px;
	padding: 0.75rem;
	display: flex;
	flex-direction: column;
	gap: 0.5rem;
}

.option-row {
	display: grid;
	grid-template-columns: 56px 1fr auto auto;
	gap: 0.45rem;
	align-items: start;
}

@media (max-width: 560px) {
	.option-row {
		grid-template-columns: 1fr 1fr;
	}
}

.msg {
	padding: 0.65rem 0.8rem;
	border-radius: 8px;
	margin-bottom: 0.75rem;
	font-size: 0.9rem;
}

.msg.error {
	background: var(--bad-bg);
	color: #fca5a5;
	text-align: left;
}

.msg.ok {
	background: var(--ok-bg);
	color: #86efac;
}

.login-box {
	max-width: 400px;
	margin: 3rem auto;
}

.brand-link {
	color: inherit;
	text-decoration: none;
}

.brand-link:hover {
	text-decoration: none;
}

.brand-link h1 {
	margin: 0;
}

.header-nav {
	display: flex;
	flex-wrap: wrap;
	gap: 0.5rem;
}

.session-score {
	position: sticky;
	top: 0;
	z-index: 20;
	background: rgba(26, 35, 50, 0.92);
	backdrop-filter: blur(8px);
	border: 1px solid var(--border);
	border-radius: 10px;
	padding: 0.5rem 0.85rem;
	margin-bottom: 0.85rem;
	font-size: 0.9rem;
	color: var(--muted);
}

[data-theme="light"] .session-score {
	background: rgba(255, 255, 255, 0.92);
}

.onboarding {
	margin-bottom: 1rem;
}

.onboarding .sub {
	margin: 0.35rem 0 0.75rem;
}

.mode-link {
	display: inline-flex;
	align-items: center;
	padding: 0.45rem 0.85rem;
	border: 1px solid var(--border);
	border-radius: 8px;
	color: var(--muted);
	font-weight: 600;
	font-size: 0.9rem;
	text-decoration: none;
}

.mode-link:hover {
	background: var(--surface2);
	text-decoration: none;
	color: var(--text);
}

.load-more-wrap {
	display: flex;
	justify-content: center;
	margin: 1.25rem 0 0.5rem;
}

.badge.diff-easy {
	color: #86efac;
	border-color: #166534;
	background: rgba(34, 197, 94, 0.12);
}

.badge.diff-medium {
	color: #fcd34d;
	border-color: #854d0e;
	background: rgba(245, 158, 11, 0.12);
}

.badge.diff-hard {
	color: #fca5a5;
	border-color: #991b1b;
	background: rgba(239, 68, 68, 0.12);
}

.badge.diff-new {
	color: #c4b5fd;
	border-color: #5b21b6;
	background: rgba(139, 92, 246, 0.12);
}

.feedback-row {
	display: flex;
	flex-wrap: wrap;
	align-items: center;
	gap: 0.4rem;
	margin-top: 0.75rem;
}

.feedback-row .muted,
.muted {
	color: var(--muted);
	font-size: 0.85rem;
}

.related {
	margin-top: 0.85rem;
	padding-top: 0.75rem;
	border-top: 1px solid var(--border);
}

.related-title {
	margin: 0 0 0.4rem;
	font-size: 0.85rem;
	text-transform: uppercase;
	letter-spacing: 0.04em;
	color: var(--muted);
}

.related-list {
	margin: 0;
	padding-left: 1.1rem;
}

.related-list li {
	margin: 0.25rem 0;
}

.related-why {
	display: block;
	font-size: 0.75rem;
	color: var(--muted);
	margin-top: 0.15rem;
}

.daily-hero h2 {
	margin: 0 0 0.35rem;
	font-size: 1.15rem;
}

.daily-progress {
	margin-top: 0.5rem;
	font-weight: 600;
	color: var(--accent);
}

.leaderboard {
	margin: 0.5rem 0 0;
	padding-left: 1.25rem;
}

.daily-submit {
	margin-top: 0.75rem;
	align-items: end;
}

.hotseat {
	display: flex;
	flex-direction: column;
	gap: 1rem;
}

.hs-stage {
	display: grid;
	grid-template-columns: 140px 1fr;
	gap: 1rem;
	align-items: start;
}

@media (max-width: 640px) {
	.hs-stage {
		grid-template-columns: 1fr;
	}

	.hs-rail {
		order: -1;
	}

	.hs-ladder {
		display: flex;
		flex-direction: row-reverse;
		overflow-x: auto;
		gap: 0.35rem;
		padding-bottom: 0.25rem;
	}

	.hs-ladder .hs-step {
		flex: 0 0 auto;
		min-width: 4.5rem;
		border-bottom: none;
		border-right: 1px solid var(--border);
		flex-direction: column;
		padding: 0.4rem 0.5rem;
	}

	.hs-ladder .hs-step:last-child {
		border-right: none;
	}
}

.hs-rail {
	padding: 0.65rem 0.5rem;
	position: sticky;
	top: 0.5rem;
}

.hs-ladder {
	list-style: none;
	margin: 0;
	padding: 0;
}

.hs-step {
	display: flex;
	align-items: center;
	justify-content: space-between;
	gap: 0.35rem;
	padding: 0.35rem 0.45rem;
	font-size: 0.78rem;
	font-weight: 650;
	border-bottom: 1px solid var(--border);
	color: var(--muted);
}

.hs-step:last-child {
	border-bottom: none;
}

.hs-step .hs-n {
	opacity: 0.7;
	font-variant-numeric: tabular-nums;
}

.hs-step.locked {
	opacity: 0.55;
}

.hs-step.current {
	color: #fff;
	background: linear-gradient(90deg, var(--accent), #1d4ed8);
	border-radius: 6px;
	border-bottom-color: transparent;
	box-shadow: 0 0 0 1px rgba(59, 130, 246, 0.4);
}

.hs-step.cleared {
	color: var(--ok);
	background: var(--ok-bg);
	border-radius: 6px;
	border-bottom-color: transparent;
}

.hs-step.failed {
	color: var(--bad);
	background: var(--bad-bg);
	border-radius: 6px;
	border-bottom-color: transparent;
}

.hs-question .quiz-card {
	margin: 0;
}

.hs-continue {
	margin-top: 0.75rem;
}

.hs-next-note {
	margin: 0.65rem 0 0;
	font-size: 0.9rem;
}

.embed-credit {
	text-align: center;
	font-size: 0.8rem;
	color: var(--muted);
	margin: 0.75rem 0 0;
}

.hp-field {
	position: absolute;
	left: -9999px;
	height: 0;
	overflow: hidden;
}

.site-footer a {
	color: var(--muted);
}

.site-footer a:hover {
	color: var(--accent);
}

.quiz-card:focus {
	outline: 2px solid var(--accent);
	outline-offset: 2px;
}

@media (max-width: 560px) {
	.toolbar {
		flex-direction: column;
		align-items: stretch;
	}

	.toolbar .field {
		min-width: 0;
	}

	.header-nav .btn {
		padding: 0.45rem 0.7rem;
		font-size: 0.85rem;
	}
}