:root {
  color-scheme: dark;
  --bg: #10384f;
  --panel: #123e55;
  --panel2: #194a60;
  --text: #f4f7fb;
  --muted: #bbd2dd;
  --line: rgba(148,163,184,.18);
  --accent: #22c55e;
  --accent2: #14b8a6;
  --sag-teal: #08b1ad;
  --sag-orange: #f47e38;
  --danger: #fb7185;
  --warning: #fbbf24;
  --shadow: 0 20px 50px rgba(0,0,0,.22);
}
html[data-theme="light"] {
  color-scheme: light;
  --bg: #eaf5f6;
  --panel: #ffffff;
  --panel2: #e0f0f1;
  --text: #0f172a;
  --muted: #64748b;
  --line: rgba(15,23,42,.12);
  --shadow: 0 18px 45px rgba(15,23,42,.08);
}
* { box-sizing: border-box; }
body { margin:0; font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif; background:var(--bg); color:var(--text); }
button, select { font:inherit; }
button { cursor:pointer; }
.hidden { display:none !important; }
.app-shell { min-height:100dvh; width:min(1180px,100%); margin:0 auto; padding:0 18px; }
.topbar { height:76px; display:flex; align-items:center; justify-content:space-between; border-bottom:1px solid var(--line); position:sticky; top:0; z-index:20; background:color-mix(in srgb, var(--bg) 88%, transparent); backdrop-filter: blur(16px); }
.brand-btn { display:flex; align-items:center; gap:12px; border:0; background:none; color:var(--text); padding:0; text-align:left; }
.brand-mark { display:grid; place-items:center; width:44px; height:44px; border-radius:14px; background:linear-gradient(145deg,var(--accent),var(--accent2)); color:#04120a; font-weight:900; letter-spacing:.5px; }
.brand-copy { display:grid; line-height:1.08; }
.brand-copy strong { font-size:1.05rem; }
.brand-copy small { color:var(--muted); margin-top:4px; }
.top-actions { display:flex; gap:8px; align-items:center; }
.icon-btn,.ghost-btn,.secondary-btn,.primary-btn,.link-btn { border-radius:12px; border:1px solid var(--line); padding:11px 15px; background:var(--panel); color:var(--text); transition:.18s ease; }
.icon-btn { width:44px; height:44px; padding:0; }
.primary-btn { background:linear-gradient(135deg,var(--accent),var(--accent2)); color:#04120a; border-color:transparent; font-weight:800; }
.secondary-btn { background:var(--panel2); font-weight:700; }
.link-btn { border:0; background:none; color:var(--accent); padding:6px; font-weight:800; }
button:hover { transform:translateY(-1px); filter:brightness(1.04); }
button:disabled { opacity:.45; cursor:not-allowed; transform:none; }
.hero { display:grid; grid-template-columns:1fr auto; gap:24px; align-items:end; padding:54px 0 30px; }
.hero h1,.quiz-head h1,.result-hero h1 { font-size:clamp(2rem,5vw,4.2rem); line-height:.98; margin:8px 0 16px; letter-spacing:-.05em; }
.hero p { color:var(--muted); max-width:760px; font-size:1.05rem; line-height:1.65; margin:0; }
.eyebrow,.tag { color:var(--accent); font-weight:900; font-size:.76rem; letter-spacing:.14em; }
.hero-score { width:170px; aspect-ratio:1; border-radius:32px; background:var(--panel); box-shadow:var(--shadow); display:grid; place-content:center; text-align:center; border:1px solid var(--line); }
.hero-score strong { font-size:3rem; line-height:1; }
.hero-score span { color:var(--muted); margin-top:8px; }
.notice { display:flex; gap:16px; align-items:center; justify-content:space-between; padding:15px 18px; border:1px solid color-mix(in srgb,var(--accent) 34%,var(--line)); background:color-mix(in srgb,var(--accent) 8%,var(--panel)); border-radius:16px; margin-bottom:22px; }
.notice span { color:var(--muted); }
.mode-grid { display:grid; grid-template-columns:repeat(2,minmax(0,1fr)); gap:16px; }
.mode-card { display:flex; flex-direction:column; gap:18px; padding:22px; background:var(--panel); border:1px solid var(--line); border-radius:22px; box-shadow:var(--shadow); }
.mode-card.featured { background:linear-gradient(155deg,color-mix(in srgb,var(--accent) 12%,var(--panel)),var(--panel)); }
.mode-card h2 { margin:5px 0 8px; font-size:1.45rem; }
.mode-card p { margin:0; color:var(--muted); line-height:1.55; }
.mode-card > button { margin-top:auto; align-self:flex-start; }
.card-icon { width:48px; height:48px; display:grid; place-items:center; border-radius:14px; background:var(--panel2); font-size:1.35rem; }
.chapter-row { display:flex; gap:10px; margin-top:auto; }
.chapter-row select { width:100%; min-width:0; border:1px solid var(--line); border-radius:12px; padding:11px 12px; background:var(--panel2); color:var(--text); }
.stats-panel { margin-top:16px; display:grid; grid-template-columns:repeat(4,1fr); gap:10px; }
.stat { background:var(--panel); border:1px solid var(--line); border-radius:18px; padding:18px; display:grid; }
.stat span,.stat small { color:var(--muted); }
.stat strong { font-size:1.45rem; margin:7px 0 2px; }
.about-panel,.continue-card { margin-top:16px; background:var(--panel); border:1px solid var(--line); border-radius:18px; padding:16px 18px; }
.about-panel p { color:var(--muted); line-height:1.6; }
.continue-card { display:flex; justify-content:space-between; gap:14px; align-items:center; }
.continue-card p { margin:4px 0 0; color:var(--muted); }
.footer { display:flex; justify-content:space-between; gap:18px; color:var(--muted); font-size:.82rem; padding:30px 0; margin-top:24px; border-top:1px solid var(--line); }

.quiz-head { padding:34px 0 22px; display:flex; justify-content:space-between; gap:20px; align-items:end; }
.quiz-head h1 { font-size:clamp(1.7rem,4vw,3rem); margin-bottom:0; }
.quiz-metrics { display:flex; gap:10px; }
.metric { min-width:112px; padding:12px 14px; border-radius:14px; background:var(--panel); border:1px solid var(--line); display:grid; }
.metric small { color:var(--muted); }
.metric strong { font-size:1.2rem; margin-top:2px; }
.metric.danger strong { color:var(--danger); }
.quiz-layout { display:grid; grid-template-columns:minmax(0,1fr) 270px; gap:16px; align-items:start; }
.question-card,.navigator-card { background:var(--panel); border:1px solid var(--line); border-radius:22px; box-shadow:var(--shadow); }
.question-card { padding:clamp(18px,3vw,30px); }
.question-meta { display:flex; justify-content:space-between; gap:12px; color:var(--muted); font-size:.85rem; margin-bottom:18px; }
.question-card h2 { white-space:pre-line; font-size:clamp(1.08rem,2.4vw,1.45rem); line-height:1.55; letter-spacing:-.01em; margin:0 0 22px; }
.options { display:grid; gap:11px; }
.option-btn { width:100%; text-align:left; display:grid; grid-template-columns:38px 1fr; gap:12px; align-items:flex-start; border:1px solid var(--line); border-radius:16px; background:var(--panel2); color:var(--text); padding:14px; line-height:1.45; }
.option-key { width:34px; height:34px; border-radius:10px; display:grid; place-items:center; background:var(--panel); border:1px solid var(--line); font-weight:900; }
.option-btn.selected { border-color:var(--accent); box-shadow:0 0 0 2px color-mix(in srgb,var(--accent) 20%,transparent); }
.option-btn.correct { border-color:var(--accent); background:color-mix(in srgb,var(--accent) 11%,var(--panel2)); }
.option-btn.wrong { border-color:var(--danger); background:color-mix(in srgb,var(--danger) 10%,var(--panel2)); }
.option-btn.locked { cursor:default; }
.feedback { border-radius:14px; padding:14px 16px; margin-top:16px; line-height:1.5; }
.feedback.good { background:color-mix(in srgb,var(--accent) 12%,var(--panel2)); border:1px solid color-mix(in srgb,var(--accent) 45%,var(--line)); }
.feedback.bad { background:color-mix(in srgb,var(--danger) 10%,var(--panel2)); border:1px solid color-mix(in srgb,var(--danger) 45%,var(--line)); }
.question-actions { margin-top:24px; display:flex; gap:10px; justify-content:space-between; flex-wrap:wrap; }
.navigator-card { padding:16px; position:sticky; top:92px; }
.nav-head { display:flex; justify-content:space-between; align-items:center; margin-bottom:14px; }
.nav-grid { display:grid; grid-template-columns:repeat(5,1fr); gap:7px; }
.nav-q { aspect-ratio:1; border-radius:9px; border:1px solid var(--line); background:var(--panel2); color:var(--muted); padding:0; }
.nav-q.answered { color:var(--text); border-color:color-mix(in srgb,var(--accent) 45%,var(--line)); background:color-mix(in srgb,var(--accent) 10%,var(--panel2)); }
.nav-q.flagged { box-shadow:inset 0 -3px 0 var(--warning); }
.nav-q.current { border-color:var(--accent); color:var(--accent); font-weight:900; }
.legend { display:grid; gap:6px; color:var(--muted); font-size:.75rem; margin-top:14px; }
.legend span { display:flex; gap:7px; align-items:center; }
.dot { width:10px; height:10px; border-radius:50%; border:1px solid var(--line); }
.dot.current { border-color:var(--accent); }
.dot.answered { background:color-mix(in srgb,var(--accent) 35%,transparent); }
.dot.flagged { background:var(--warning); }

.result-hero { text-align:center; padding:55px 0 28px; }
.result-score { width:180px; aspect-ratio:1; border-radius:50%; margin:0 auto 24px; display:grid; place-content:center; background:var(--panel); border:10px solid var(--accent); box-shadow:var(--shadow); }
.result-score strong { display:block; font-size:3rem; line-height:1; }
.result-score span { color:var(--muted); margin-top:5px; }
.result-hero h1 { margin:10px 0 12px; }
.result-hero p { color:var(--muted); max-width:650px; margin:0 auto; line-height:1.6; }
.result-actions { display:flex; gap:10px; justify-content:center; flex-wrap:wrap; margin-top:24px; }
.review-list { display:grid; gap:12px; max-width:900px; margin:0 auto; }
.review-item { background:var(--panel); border:1px solid var(--line); border-radius:18px; padding:18px; }
.review-item h3 { margin:0 0 10px; line-height:1.45; white-space:pre-line; }
.review-item p { margin:7px 0; color:var(--muted); }
.review-item .right { color:var(--accent); }
.review-item .wrong-answer { color:var(--danger); }

@media (max-width: 820px) {
  .hero { grid-template-columns:1fr; }
  .hero-score { width:132px; }
  .mode-grid { grid-template-columns:1fr; }
  .stats-panel { grid-template-columns:repeat(2,1fr); }
  .footer { flex-direction:column; }
  .quiz-head { align-items:stretch; flex-direction:column; }
  .quiz-layout { grid-template-columns:1fr; }
  .navigator-card { position:static; order:2; }
  .nav-grid { grid-template-columns:repeat(10,1fr); }
}
@media (max-width: 520px) {
  .app-shell { padding:0 12px; }
  .topbar { height:68px; }
  .brand-copy small { display:none; }
  .hero { padding-top:34px; }
  .hero h1 { font-size:2.45rem; }
  .notice { align-items:flex-start; flex-direction:column; gap:4px; }
  .chapter-row { flex-direction:column; }
  .chapter-row button { width:100%; }
  .stats-panel { grid-template-columns:repeat(2,1fr); }
  .quiz-metrics { width:100%; }
  .metric { flex:1; min-width:0; }
  .nav-grid { grid-template-columns:repeat(8,1fr); }
  .question-actions { display:grid; grid-template-columns:1fr 1fr; }
  .question-actions #nextBtn { grid-column:1 / -1; }
}
/* SAG brand and bilingual controls */
body { background:radial-gradient(ellipse at 90% 5%,#08b1ad16,transparent 48%),var(--bg); }
.topbar { min-height:96px; height:auto; padding:14px 0; gap:18px; border-bottom:2px solid var(--sag-teal); }
.brand-logo { width:220px; height:auto; display:block; border-radius:6px; }
.brand-copy { border-left:2px solid var(--sag-orange); padding-left:14px; }
.language-switch { display:flex; border:1px solid var(--sag-teal); border-radius:12px; padding:3px; gap:3px; }
.language-switch button { min-height:38px; min-width:44px; border:0; border-radius:8px; background:transparent; color:var(--text); font-weight:800; }
.language-switch button[aria-pressed="true"] { background:var(--sag-teal); color:#062b3b; }
.eyebrow,.tag { color:var(--sag-orange); font-size:.875rem; letter-spacing:.08em; }
html[data-theme="light"] .eyebrow,html[data-theme="light"] .tag { color:#a64714; }
.hero h1 { font-size:clamp(2rem,4.3vw,3.65rem); line-height:1.12; letter-spacing:-.035em; }
.hero { padding-top:34px; }
.hero-score { border-top:4px solid var(--sag-orange); }
.mode-card.featured { border-color:var(--sag-teal); background:linear-gradient(145deg,color-mix(in srgb,var(--sag-teal) 13%,var(--panel)),var(--panel)); }
.secondary-btn { background:#22c55e; color:#04120a; border-color:transparent; }
.legend,.footer,.question-meta,.brand-copy small { font-size:.875rem; }
.question-meta { flex-wrap:wrap; }
.option-btn:disabled { opacity:1; }
button:focus-visible,select:focus-visible { outline:3px solid var(--sag-orange); outline-offset:3px; }
@media(max-width:680px){.topbar{flex-wrap:wrap;position:relative;gap:12px}.brand-logo{width:180px}.brand-copy strong{font-size:1rem}.brand-copy small{display:none}.top-actions{margin-left:auto}.hero h1{font-size:2.2rem}.navigator-card{top:16px}}
@media(max-width:380px){.brand-logo{width:150px}.brand-copy{padding-left:8px}.hero h1{font-size:1.9rem}.continue-card{align-items:stretch;flex-direction:column}}