/* ============================================================
 * Quiz portal — functional baseline stylesheet.
 * Visual polish (typography, palette, micro-interactions) is layered
 * on top of this by the frontend-design pass; structural rules and
 * accessibility-relevant defaults live here.
 * ============================================================ */

:root {
  color-scheme: light dark;
  --bg: #f6f7f9;
  --surface: #ffffff;
  --border: #d9dee7;
  --text: #18212f;
  --muted: #5b6573;
  --primary: #0d6b57;
  --primary-text: #ffffff;
  --warn: #b67700;
  --warn-text: #ffffff;
  --danger: #a43831;
  --danger-text: #ffffff;
  --info: #254f7a;
  --accent: #1c8a72;
  --correct-bg: #e6f4ed;
  --correct-border: #199870;
  --wrong-border: #d04040;
  --shadow: 0 8px 28px rgba(15, 25, 42, 0.06);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background: var(--bg);
  color: var(--text);
}

* { box-sizing: border-box; }

body {
  margin: 0;
  min-height: 100dvh;
  background: var(--bg);
  color: var(--text);
  font-size: 16px;
  line-height: 1.45;
}

h1, h2, h3 { margin: 0 0 0.4rem; line-height: 1.2; }
h1 { font-size: 1.4rem; font-weight: 700; letter-spacing: -0.01em; }
h2 { font-size: 1.05rem; font-weight: 700; }
h3 { font-size: 0.95rem; font-weight: 700; color: var(--muted); text-transform: uppercase; letter-spacing: 0.06em; }
p { margin: 0 0 0.6rem; }
code { font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; font-size: 0.85em; }

.muted { color: var(--muted); }
.small { font-size: 0.85rem; }
.eyebrow { color: var(--muted); font-size: 0.8rem; text-transform: uppercase; letter-spacing: 0.08em; margin: 0 0 0.4rem; }

/* ---------- Layout containers ---------- */

.bootstrap-loading {
  display: grid;
  place-items: center;
  min-height: 100dvh;
  color: var(--muted);
  font-size: 0.95rem;
}

.centered-shell {
  display: grid;
  place-items: center;
  min-height: 100dvh;
  padding: 24px;
}

/* ---------- Cards & panels ---------- */

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 14px;
  box-shadow: var(--shadow);
  padding: 24px;
}

.card.narrow { width: min(440px, 100%); }
.card-header { margin-bottom: 16px; }
.card.center { text-align: center; }

.panel { padding: 20px; }
.panel + .panel { margin-top: 16px; }
.panel h2 { margin-bottom: 12px; display: flex; align-items: center; gap: 8px; }
.panel h2 .count {
  background: var(--info);
  color: #fff;
  border-radius: 999px;
  padding: 2px 10px;
  font-size: 0.75rem;
}

.stack { display: grid; gap: 14px; }

/* ---------- Forms ---------- */

.field { display: grid; gap: 6px; }
.field > span { font-weight: 600; font-size: 0.9rem; color: var(--muted); }

input, textarea, select {
  font: inherit;
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 10px 12px;
  background: var(--surface);
  color: var(--text);
  outline: none;
}
input:focus, textarea:focus, select:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--primary) 25%, transparent);
}

/* ---------- Buttons ---------- */

.btn, button {
  font: inherit;
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 10px 16px;
  background: var(--surface);
  color: var(--text);
  cursor: pointer;
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  transition: transform 0.05s ease, background 0.15s ease, border-color 0.15s ease;
}
.btn:active, button:active { transform: translateY(1px); }
.btn:disabled, button:disabled { cursor: not-allowed; opacity: 0.55; }

.btn.primary { background: var(--primary); border-color: var(--primary); color: var(--primary-text); }
.btn.warn { background: var(--warn); border-color: var(--warn); color: var(--warn-text); }
.btn.danger { background: var(--danger); border-color: var(--danger); color: var(--danger-text); }
.btn.ghost { background: transparent; }
.btn.block { width: 100%; }
.btn.big { padding: 14px 20px; font-size: 1.05rem; font-weight: 600; }
.btn.small { padding: 6px 10px; font-size: 0.85rem; }

/* ---------- Alerts ---------- */

.alert { padding: 10px 14px; border-radius: 8px; font-size: 0.9rem; }
.alert.error { background: color-mix(in srgb, var(--danger) 15%, transparent); border: 1px solid var(--danger); color: var(--danger); }
.alert.info { background: color-mix(in srgb, var(--info) 12%, transparent); border: 1px solid var(--info); color: var(--info); }

/* ---------- Admin topbar ---------- */

.admin-body { padding-bottom: 32px; }

.topbar {
  display: flex;
  justify-content: space-between;
  align-items: flex-end;
  gap: 16px;
  padding: 20px 24px 16px;
  border-bottom: 1px solid var(--border);
  flex-wrap: wrap;
}
.topbar-title h1 { font-size: 1.25rem; }
.topbar-title p { margin: 0; }
.topbar-actions { display: flex; gap: 10px; align-items: center; }

.state-badge {
  border-radius: 999px;
  padding: 4px 12px;
  font-size: 0.8rem;
  font-weight: 600;
  border: 1px solid var(--border);
}
.state-badge.state-lobby { background: color-mix(in srgb, var(--info) 18%, transparent); color: var(--info); border-color: var(--info); }
.state-badge.state-question_open { background: color-mix(in srgb, var(--primary) 18%, transparent); color: var(--primary); border-color: var(--primary); }
.state-badge.state-question_closed { background: color-mix(in srgb, var(--warn) 18%, transparent); color: var(--warn); border-color: var(--warn); }
.state-badge.state-finished { background: color-mix(in srgb, var(--accent) 18%, transparent); color: var(--accent); border-color: var(--accent); }
.state-badge.state-correct { background: var(--correct-bg); color: var(--accent); border-color: var(--correct-border); }
.state-badge.state-wrong { background: color-mix(in srgb, var(--danger) 12%, transparent); color: var(--danger); border-color: var(--wrong-border); }

/* ---------- Admin dashboard layout ---------- */

.dashboard {
  display: grid;
  gap: 16px;
  grid-template-columns: minmax(280px, 360px) 1fr;
  padding: 20px 24px;
  align-items: start;
}
@media (max-width: 800px) {
  .dashboard { grid-template-columns: 1fr; }
}

.dashboard-side { display: grid; gap: 16px; }
.dashboard-main { display: grid; gap: 16px; }

/* ---------- Join panel (QR + URL + roster) ---------- */

.qr-wrap {
  background: #fff;
  padding: 14px;
  border-radius: 10px;
  border: 1px solid var(--border);
  display: grid;
  place-items: center;
  margin-bottom: 12px;
}
.qr-wrap img { width: 100%; height: auto; max-width: 280px; display: block; }
.qr-fallback { padding: 40px; color: var(--muted); }

.join-url-row { display: flex; gap: 8px; align-items: center; flex-wrap: wrap; }
.join-url {
  flex: 1 1 200px;
  background: color-mix(in srgb, var(--info) 8%, transparent);
  padding: 6px 10px;
  border-radius: 6px;
  font-size: 0.85rem;
  word-break: break-all;
}

.roster {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 6px;
  max-height: 360px;
  overflow-y: auto;
}
.roster li { display: flex; align-items: center; gap: 10px; padding: 6px 0; border-bottom: 1px solid var(--border); }
.roster li:last-child { border-bottom: none; }
.roster .dot { width: 8px; height: 8px; border-radius: 999px; background: var(--accent); flex-shrink: 0; }
.roster .who { display: grid; line-height: 1.2; }
.roster .who small { color: var(--muted); font-size: 0.8rem; }

/* ---------- State CTA panel (lobby / finished) ---------- */

.state-cta { display: grid; gap: 10px; }
.state-cta .btn.big { justify-self: start; }

.action-row { display: flex; gap: 10px; flex-wrap: wrap; margin-top: 16px; }

/* ---------- Question card (admin + student share) ---------- */

.question-head {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 12px;
  margin-bottom: 10px;
}
.qnum { font-weight: 700; color: var(--muted); font-size: 0.9rem; }
.countdown {
  font-weight: 700;
  font-size: 1.1rem;
  font-variant-numeric: tabular-nums;
  color: var(--primary);
}

.qbar {
  height: 8px;
  background: color-mix(in srgb, var(--primary) 14%, transparent);
  border-radius: 999px;
  overflow: hidden;
  margin-bottom: 16px;
}
.qbar span {
  display: block;
  height: 100%;
  width: 100%;
  background: var(--primary);
  transition: width 0.2s linear;
}

.question-text { font-size: 1.2rem; font-weight: 600; margin: 8px 0 16px; }
.question-text.small { font-size: 1rem; }

.options {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 10px;
}
.options li {
  display: grid;
  grid-template-columns: 36px 1fr auto;
  gap: 12px;
  align-items: center;
  padding: 10px 14px;
  background: color-mix(in srgb, var(--info) 4%, transparent);
  border: 1px solid var(--border);
  border-radius: 10px;
}
.options .key {
  background: var(--info);
  color: #fff;
  font-weight: 700;
  border-radius: 6px;
  padding: 4px 0;
  text-align: center;
  width: 36px;
}
.options .opt-text { color: var(--text); }
.options .opt-count { color: var(--muted); font-size: 0.85rem; }

.options.reveal li.correct {
  background: var(--correct-bg);
  border-color: var(--correct-border);
}
.options.reveal li.correct .key { background: var(--correct-border); }
.options.reveal li.wrong-pick { border-color: var(--wrong-border); }
.options.reveal li.wrong-pick .key { background: var(--danger); }

.explanation {
  background: color-mix(in srgb, var(--accent) 8%, transparent);
  padding: 12px 14px;
  border-radius: 10px;
  border-left: 3px solid var(--accent);
  margin-top: 14px;
  font-size: 0.95rem;
}

/* ---------- Histogram ---------- */

.hist { margin-top: 16px; display: grid; gap: 8px; }
.hist-summary { display: flex; gap: 12px; flex-wrap: wrap; font-size: 0.9rem; }
.hist-rows { display: grid; gap: 6px; }
.hist-row {
  display: grid;
  grid-template-columns: 36px 1fr 80px;
  gap: 10px;
  align-items: center;
}
.hist-row .bar {
  height: 8px;
  background: color-mix(in srgb, var(--info) 12%, transparent);
  border-radius: 999px;
  overflow: hidden;
}
.hist-row .bar .fill {
  display: block;
  height: 100%;
  background: var(--info);
  transition: width 0.3s ease;
}
.hist-row.is-correct .bar .fill { background: var(--correct-border); }
.hist-row.missed .bar { background: transparent; }
.hist-row .num { font-size: 0.85rem; text-align: right; color: var(--muted); }

/* ---------- Leaderboard ---------- */

.leaderboard {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 4px;
}
.leaderboard li {
  display: grid;
  grid-template-columns: 32px 1fr auto;
  gap: 12px;
  align-items: center;
  padding: 8px 12px;
  border-radius: 8px;
}
.leaderboard li:nth-child(odd) { background: color-mix(in srgb, var(--info) 5%, transparent); }
.leaderboard .rank { font-weight: 700; color: var(--muted); font-variant-numeric: tabular-nums; }
.leaderboard .who { display: grid; line-height: 1.2; }
.leaderboard .who small { color: var(--muted); font-size: 0.78rem; }
.leaderboard .score { font-weight: 700; font-variant-numeric: tabular-nums; color: var(--primary); }

/* ---------- Student-side answer buttons (big, tappable) ---------- */

.quiz-card { width: min(640px, 100%); }
.answer-grid {
  display: grid;
  gap: 12px;
  margin: 18px 0 0;
}
.answer-btn {
  display: grid;
  grid-template-columns: 48px 1fr;
  gap: 14px;
  align-items: center;
  text-align: left;
  background: var(--surface);
  border: 2px solid var(--border);
  border-radius: 12px;
  padding: 18px 18px;
  font-size: 1rem;
  min-height: 64px;
}
.answer-btn:hover:not(:disabled) {
  border-color: var(--primary);
  background: color-mix(in srgb, var(--primary) 6%, transparent);
}
.answer-btn.picked {
  border-color: var(--primary);
  background: color-mix(in srgb, var(--primary) 12%, transparent);
}
.answer-btn .answer-key {
  background: var(--info);
  color: #fff;
  font-weight: 700;
  border-radius: 8px;
  padding: 6px 0;
  text-align: center;
  width: 48px;
  font-size: 1.05rem;
}
.answer-btn .answer-text { font-weight: 500; }

.big-score {
  font-size: 3rem;
  font-weight: 800;
  color: var(--primary);
  margin: 8px 0 4px;
  font-variant-numeric: tabular-nums;
}

.spinner {
  width: 28px;
  height: 28px;
  margin: 12px auto 0;
  border: 3px solid var(--border);
  border-top-color: var(--primary);
  border-radius: 50%;
  animation: spin 1s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }

/* ---------- Reveal stats (student) ---------- */

.reveal-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
  margin: 16px 0;
}
.reveal-stats .stat {
  text-align: center;
  padding: 12px 8px;
  background: color-mix(in srgb, var(--info) 6%, transparent);
  border-radius: 10px;
}
.reveal-stats .stat span { display: block; font-size: 0.8rem; }
.reveal-stats .stat b { display: block; font-size: 1.4rem; margin-top: 4px; }
.reveal-stats .stat.big b { font-size: 2.2rem; color: var(--primary); }

.celebration-card {
  text-align: center;
  width: min(640px, 100%);
  position: relative;
}
.celebration-banner {
  background: var(--primary);
  color: #fff;
  padding: 14px 20px;
  border-radius: 10px;
  font-weight: 700;
  font-size: 1.1rem;
  margin: -8px 0 20px;
}

/* ---------- Dark mode ---------- */

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0f1117;
    --surface: #181c25;
    --border: #2c3340;
    --text: #edf1f7;
    --muted: #98a3b3;
    --primary: #4ec9aa;
    --primary-text: #061612;
    --warn: #f0b441;
    --warn-text: #1a1102;
    --danger: #f06a6a;
    --info: #5489c6;
    --accent: #6dd2b6;
    --correct-bg: rgba(78, 201, 170, 0.18);
    --correct-border: #4ec9aa;
    --shadow: 0 8px 28px rgba(0, 0, 0, 0.4);
  }
  .qr-wrap { background: #fff; }
  .join-url { background: rgba(84, 137, 198, 0.12); }
}