:root {
  color-scheme: light;
  --navy: #102b46;
  --navy-2: #183e63;
  --gold: #d1a33b;
  --gold-soft: #f6ebcb;
  --paper: #f7f8fa;
  --ink: #17202a;
  --muted: #657383;
  --line: #dce2e8;
  --white: #ffffff;
  --good: #147a56;
  --good-soft: #e8f6ef;
  --bad: #bc3b3b;
  --bad-soft: #fff0ef;
  --shadow: 0 24px 64px rgba(16, 43, 70, 0.13);
}

* { box-sizing: border-box; }
html { min-height: 100%; background: var(--paper); }
body {
  min-height: 100%; margin: 0; color: var(--ink); background:
    radial-gradient(circle at 5% 0%, rgba(209,163,59,.14), transparent 26rem),
    linear-gradient(180deg, #edf2f6 0, var(--paper) 25rem);
  font-family: "Microsoft YaHei", "PingFang SC", system-ui, sans-serif;
  font-size: 16px; line-height: 1.65;
}
button, input { font: inherit; }
button { touch-action: manipulation; }
.app-shell { width: min(100% - 28px, 720px); min-height: 100vh; margin: 0 auto; padding: max(28px, env(safe-area-inset-top)) 0 max(36px, env(safe-area-inset-bottom)); }
.welcome-card, .exam-card, .result-card {
  position: relative; overflow: hidden; background: rgba(255,255,255,.97); border: 1px solid rgba(16,43,70,.10);
  border-radius: 28px; box-shadow: var(--shadow); padding: clamp(24px, 6vw, 44px);
}
.welcome-card { margin-top: min(10vh, 84px); text-align: center; }
.welcome-card::before { content:""; position:absolute; inset:0 0 auto; height:7px; background:linear-gradient(90deg,var(--navy),var(--gold)); }
.brand-mark { display:grid; place-items:center; width:64px; height:64px; margin:0 auto 18px; border-radius:20px; color:var(--gold-soft); background:var(--navy); font:700 34px/1 Georgia,serif; box-shadow:0 12px 24px rgba(16,43,70,.2); }
.eyebrow { margin:0; color:var(--gold); font-size:.875rem; font-weight:800; letter-spacing:.16em; }
h1 { margin:8px 0 14px; color:var(--navy); font-size:clamp(1.9rem,7vw,2.8rem); line-height:1.2; letter-spacing:-.03em; }
.intro { max-width:34rem; margin:0 auto; color:var(--muted); }
.paper-mix { display:grid; grid-template-columns:repeat(3,1fr); gap:10px; margin:28px 0; }
.paper-mix span { padding:12px 6px; border-radius:14px; color:var(--muted); background:#f1f4f7; font-size:.86rem; }
.paper-mix b { display:block; color:var(--navy); font-size:1.35rem; line-height:1.25; }
.primary-button, .secondary-button { width:100%; min-height:54px; border:0; border-radius:16px; cursor:pointer; font-weight:800; transition:transform .15s ease, opacity .15s ease; }
.primary-button { color:#fff; background:var(--navy); box-shadow:0 10px 24px rgba(16,43,70,.22); }
.secondary-button { color:var(--navy); background:#eaf0f5; }
.primary-button:active, .secondary-button:active { transform:translateY(1px); }
.primary-button:disabled { opacity:.42; cursor:not-allowed; box-shadow:none; }
.bank-note { margin:14px 0 0; color:var(--muted); font-size:.82rem; }
.home-actions { display:grid; gap:10px; }
.topbar { display:flex; align-items:center; justify-content:space-between; gap:16px; margin-bottom:16px; color:var(--navy); }
.progress-meta { font-weight:800; }
.score-pill { padding:7px 12px; border-radius:999px; color:var(--navy); background:var(--gold-soft); font-weight:800; }
.progress-journey { position:relative; margin-bottom:20px; padding:18px 0; }
.progress-track { height:8px; overflow:hidden; border-radius:999px; background:#dce4eb; }
.progress-fill { height:100%; background:linear-gradient(90deg,var(--navy-2),var(--gold)); transition:width .25s ease; }
.progress-avatar { position:absolute; top:50%; width:44px; height:44px; border:3px solid #fff; border-radius:50%; object-fit:cover; object-position:50% 30%; box-shadow:0 6px 16px rgba(16,43,70,.28); transform:translateY(-50%); transition:left .25s ease; }
.question-type { display:inline-block; margin:0 0 12px; padding:5px 10px; border-radius:8px; color:var(--navy); background:#eaf0f5; font-size:.82rem; font-weight:800; }
.question-text { margin:0 0 22px; color:var(--ink); font-size:clamp(1.08rem,4vw,1.28rem); line-height:1.75; }
.option-list { display:grid; gap:12px; margin:0; padding:0; border:0; }
.option { display:grid; grid-template-columns:32px 1fr; align-items:start; gap:10px; min-height:56px; padding:13px 14px; border:1.5px solid var(--line); border-radius:16px; background:#fff; cursor:pointer; }
.option:hover { border-color:#9eacb8; }
.option.selected { border-color:var(--navy-2); background:#edf4fa; }
.option input { position:absolute; opacity:0; pointer-events:none; }
.option-key { display:grid; place-items:center; width:30px; height:30px; border-radius:9px; color:var(--navy); background:#edf1f5; font-weight:800; }
.option.selected .option-key { color:#fff; background:var(--navy); }
.option.correct { border-color:var(--good); background:var(--good-soft); }
.option.incorrect { border-color:var(--bad); background:var(--bad-soft); }
.feedback { margin:22px 0 0; padding:18px; border-radius:16px; }
.feedback.correct { color:#0f6045; background:var(--good-soft); }
.feedback.incorrect { color:#8f2d2d; background:var(--bad-soft); }
.feedback h2 { margin:0 0 8px; font-size:1.05rem; }
.feedback p { margin:5px 0 0; color:var(--ink); }
.action-row { display:grid; grid-template-columns:1fr; gap:10px; margin-top:22px; }
.section-title { margin:0 0 18px; color:var(--navy); font-size:1.5rem; }
.score-hero { display:flex; align-items:baseline; gap:8px; margin:10px 0 26px; color:var(--navy); }
.score-hero strong { font:700 clamp(3.2rem,15vw,5rem)/1 Georgia,serif; }
.metric-grid { display:grid; grid-template-columns:repeat(3,1fr); gap:10px; margin-bottom:24px; }
.metric { padding:14px 8px; border-radius:14px; background:#f1f4f7; text-align:center; }
.metric strong { display:block; color:var(--navy); font-size:1.2rem; }
.metric span { color:var(--muted); font-size:.8rem; }
.wrong-list { display:grid; gap:12px; margin:18px 0 24px; }
.wrong-item { padding:16px; border:1px solid var(--line); border-radius:14px; background:#fff; }
.wrong-item h3 { margin:0 0 7px; font-size:1rem; line-height:1.6; }
.wrong-item p { margin:3px 0; color:var(--muted); font-size:.9rem; }
.wrong-item strong { color:var(--ink); }
.perfect-note { padding:18px; border-radius:14px; color:var(--good); background:var(--good-soft); text-align:center; font-weight:800; }
.install-hint { display:none; margin-top:10px; }
.sr-only { position:absolute; width:1px; height:1px; padding:0; margin:-1px; overflow:hidden; clip:rect(0,0,0,0); white-space:nowrap; border:0; }
@media (min-width: 620px) { .action-row.two { grid-template-columns:1fr 1fr; } }
@media (max-width: 380px) { .app-shell { width:min(100% - 18px,720px); } .welcome-card,.exam-card,.result-card { border-radius:22px; padding:22px 18px; } }
@media (prefers-reduced-motion: reduce) { * { scroll-behavior:auto !important; transition:none !important; } }