:root {
  --bg: #0f172a;
  --panel: #111827;
  --panel-2: #1f2937;
  --border: #334155;
  --text: #e5e7eb;
  --muted: #94a3b8;
  --accent: #22c55e;
  --accent-2: #38bdf8;
  --danger: #ef4444;
  --warning: #f59e0b;
}

* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background: linear-gradient(180deg, #020617, #0f172a 40%, #111827);
  color: var(--text);
}

.hero {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  align-items: end;
  padding: 2rem 2rem 1rem;
}

.eyebrow {
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--accent-2);
  font-size: 0.75rem;
  margin: 0 0 0.5rem;
}

h1 {
  margin: 0;
  font-size: clamp(2rem, 4vw, 3rem);
}

.subtitle {
  color: var(--muted);
  max-width: 60ch;
}

.hero-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.pill, .badge {
  border: 1px solid var(--border);
  background: rgba(31, 41, 55, 0.8);
  color: var(--text);
  padding: 0.4rem 0.7rem;
  border-radius: 999px;
  font-size: 0.85rem;
}

.layout {
  display: grid;
  grid-template-columns: 340px 1fr;
  gap: 1rem;
  padding: 1rem 2rem 2rem;
}

.panel {
  background: rgba(17, 24, 39, 0.94);
  border: 1px solid var(--border);
  border-radius: 18px;
  box-shadow: 0 12px 40px rgba(2, 6, 23, 0.35);
}

.controls {
  padding: 1.2rem;
  align-self: start;
  position: sticky;
  top: 1rem;
}

.quiz-panel {
  padding: 1.2rem;
  min-height: 70vh;
}

label {
  display: block;
  margin-bottom: 1rem;
  color: var(--muted);
  font-size: 0.95rem;
}

input, select, button {
  width: 100%;
  border-radius: 12px;
  border: 1px solid var(--border);
  background: var(--panel-2);
  color: var(--text);
  padding: 0.8rem 0.9rem;
  margin-top: 0.4rem;
  font-size: 0.95rem;
}

button {
  cursor: pointer;
  transition: transform 0.12s ease, opacity 0.12s ease, border-color 0.12s ease;
}
button:hover { transform: translateY(-1px); }
button:disabled { opacity: 0.5; cursor: not-allowed; transform: none; }
button.primary {
  background: linear-gradient(90deg, #0f766e, #0891b2);
  border-color: #0ea5e9;
}
button.danger {
  border-color: #7f1d1d;
  background: #3f1113;
}

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

.button-column {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.stats-block {
  border-top: 1px solid rgba(148, 163, 184, 0.18);
  margin-top: 1.1rem;
  padding-top: 1.1rem;
}

.stat-grid, .summary-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.75rem;
}

.stat-grid div, .summary-grid div {
  background: rgba(31, 41, 55, 0.9);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 0.8rem;
}

.stat-label {
  display: block;
  color: var(--muted);
  font-size: 0.8rem;
  margin-bottom: 0.2rem;
}

.principles-list {
  margin: 0;
  padding-left: 1rem;
  color: var(--muted);
}
.principles-list li { margin-bottom: 0.5rem; }

.quiz-topbar {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  align-items: center;
  margin-bottom: 1rem;
}

.progress {
  margin-top: 0.5rem;
  width: min(560px, 100%);
  background: rgba(148, 163, 184, 0.2);
  border-radius: 999px;
  height: 10px;
  overflow: hidden;
}

#progressBar {
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, var(--accent), var(--accent-2));
}

.session-stats {
  display: flex;
  gap: 1rem;
  color: var(--muted);
  flex-wrap: wrap;
}

.question-card {
  background: rgba(15, 23, 42, 0.6);
  border: 1px solid var(--border);
  border-radius: 18px;
  padding: 1.2rem;
}

.meta-row {
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
  margin-bottom: 0.8rem;
}

.options {
  display: grid;
  gap: 0.8rem;
  margin-top: 1rem;
}

.option {
  text-align: left;
  background: rgba(31, 41, 55, 0.8);
}
.option.correct { border-color: #15803d; background: rgba(20, 83, 45, 0.45); }
.option.incorrect { border-color: #b91c1c; background: rgba(127, 29, 29, 0.35); }
.option.locked { pointer-events: none; }

.feedback {
  margin-top: 1rem;
  padding: 1rem;
  border-radius: 16px;
  border: 1px solid var(--border);
  background: rgba(15, 23, 42, 0.72);
}
.feedback.correct { border-color: #166534; }
.feedback.incorrect { border-color: #991b1b; }

.review-list {
  display: grid;
  gap: 0.9rem;
  margin-top: 0.8rem;
}

.review-item {
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 0.9rem;
  background: rgba(15, 23, 42, 0.6);
}

.empty-state, .summary-state {
  display: grid;
  gap: 1rem;
  place-items: start;
  padding: 2rem 0.25rem;
}

.hidden { display: none !important; }
.footer {
  padding: 0 2rem 2rem;
  color: var(--muted);
  font-size: 0.85rem;
}

@media (max-width: 980px) {
  .layout {
    grid-template-columns: 1fr;
    padding: 1rem;
  }
  .controls { position: static; }
  .hero {
    flex-direction: column;
    align-items: start;
    padding: 1.2rem 1rem 0.5rem;
  }
  .quiz-topbar {
    flex-direction: column;
    align-items: start;
  }
}

.filter-hint{font-size:.92rem;opacity:.8;margin:.25rem 0 1rem;}


.summary-note { margin: 0 0 1rem; color: #4b5563; }


.cta-card {
  width: 100%;
  background: rgba(15, 23, 42, 0.72);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 1rem;
}

.cta-card.compact {
  margin-top: 0.5rem;
}

.cta-title {
  margin: 0 0 0.35rem;
  font-weight: 700;
}

.cta-copy {
  margin: 0 0 0.9rem;
  color: var(--muted);
}

.filter-hint.limit {
  color: #fbbf24;
}