:root{
  --bg:#f3f2ef; --paper:#fff; --ink:#171717; --muted:#6c6a66; --line:#dedbd5;
  --red:#b21f2d; --red-dark:#8c1622; --blue:#244a73; --green:#247a4d; --amber:#9b6500;
  --shadow:0 18px 50px rgba(28,23,20,.09); --radius:18px;
}
*{box-sizing:border-box} html{scroll-behavior:smooth} body{margin:0;background:var(--bg);color:var(--ink);font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;min-height:100vh}
button,input{font:inherit} button{cursor:pointer}.road-stripe{position:fixed;inset:0 0 auto 0;height:5px;background:repeating-linear-gradient(90deg,var(--red) 0 90px,#fff 90px 125px,var(--blue) 125px 215px,#fff 215px 250px);z-index:20;animation:stripe 18s linear infinite}@keyframes stripe{to{background-position:500px 0}}
.topbar{height:82px;display:flex;align-items:center;justify-content:space-between;padding:10px clamp(18px,4vw,56px);border-bottom:1px solid var(--line);background:rgba(243,242,239,.94);position:sticky;top:0;z-index:10;backdrop-filter:blur(12px)}
.brand{border:0;background:none;display:flex;align-items:center;gap:12px;text-align:left;color:inherit;padding:0}.brand-mark{width:44px;height:44px;border-radius:10px;background:var(--red);color:#fff;display:grid;place-items:center;font-weight:900;letter-spacing:-1px;box-shadow:inset 0 -5px 0 rgba(0,0,0,.12)}.brand b,.brand small{display:block}.brand b{font-size:16px}.brand small{font-size:12px;color:var(--muted);margin-top:2px}.top-actions{display:flex;gap:8px}.ghost-btn,.secondary-btn,.icon-btn{border:1px solid var(--line);background:#fff;color:var(--ink);border-radius:10px;padding:10px 14px;font-weight:700;transition:.18s ease}.ghost-btn:hover,.secondary-btn:hover,.icon-btn:hover{transform:translateY(-1px);border-color:#bdb9b1}.icon-btn{padding:7px 11px;font-size:20px}
main{width:min(1180px,calc(100% - 32px));margin:0 auto;padding:46px 0 72px;min-height:calc(100vh - 150px)}
.hero{display:grid;grid-template-columns:1.25fr .75fr;gap:36px;align-items:stretch}.eyebrow{font-size:12px;letter-spacing:.16em;font-weight:900;color:var(--red);text-transform:uppercase}.hero h1{font-size:clamp(42px,6vw,78px);line-height:.94;letter-spacing:-.055em;margin:14px 0 20px;max-width:780px}.hero h1 em{font-style:normal;color:var(--red)}.lede{font-size:18px;line-height:1.65;color:#54514c;max-width:690px}.hero-panel{background:#1d2630;border-radius:24px;color:white;padding:26px;box-shadow:var(--shadow);position:relative;overflow:hidden;min-height:300px}.hero-panel:before{content:"";position:absolute;width:220px;height:220px;border:40px solid rgba(255,255,255,.055);border-radius:50%;right:-90px;top:-100px}.hero-panel .big{font-size:70px;font-weight:900;letter-spacing:-.07em;line-height:1}.hero-panel h3{margin:6px 0 14px}.hero-panel p{color:#cad1d8;line-height:1.5}.meter{height:9px;background:#39444f;border-radius:999px;overflow:hidden}.meter span{display:block;height:100%;background:#fff;width:75%;border-radius:999px}.metric-row{display:grid;grid-template-columns:repeat(3,1fr);gap:8px;margin-top:28px}.metric{padding:12px;border-radius:12px;background:rgba(255,255,255,.07)}.metric b{display:block;font-size:20px}.metric small{color:#b9c2ca}
.section-head{display:flex;justify-content:space-between;align-items:end;gap:18px;margin:48px 0 18px}.section-head h2{font-size:28px;margin:0;letter-spacing:-.03em}.section-head p{margin:0;color:var(--muted)}
.difficulty-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:12px}.difficulty-card{position:relative;border:1px solid var(--line);background:#fff;border-radius:16px;padding:20px;text-align:left;transition:.2s ease;min-height:182px}.difficulty-card:hover{transform:translateY(-3px);box-shadow:0 12px 30px rgba(20,20,20,.07)}.difficulty-card.selected{border:2px solid var(--red);padding:19px;box-shadow:0 0 0 4px rgba(178,31,45,.08)}.difficulty-card .level{font-size:11px;font-weight:900;color:var(--muted);letter-spacing:.13em}.difficulty-card h3{margin:12px 0 7px;font-size:21px}.difficulty-card p{margin:0;color:var(--muted);line-height:1.45;font-size:14px}.difficulty-card .pill{position:absolute;right:14px;top:14px;background:#f2efea;padding:6px 8px;border-radius:999px;font-size:11px;font-weight:800}.difficulty-card.selected .pill{background:#f7e6e8;color:var(--red)}
.setup-card{margin-top:16px;background:#fff;border:1px solid var(--line);border-radius:18px;padding:22px;display:flex;align-items:center;justify-content:space-between;gap:16px}.mode-seg{display:flex;gap:6px;padding:5px;background:#efede8;border-radius:12px}.mode-seg button{border:0;background:transparent;padding:10px 13px;border-radius:9px;font-weight:800;color:var(--muted)}.mode-seg button.active{background:#fff;color:var(--ink);box-shadow:0 3px 10px rgba(0,0,0,.07)}.primary-btn{border:0;background:var(--red);color:white;border-radius:12px;padding:14px 20px;font-weight:900;box-shadow:0 8px 18px rgba(178,31,45,.22);transition:.18s ease}.primary-btn:hover{background:var(--red-dark);transform:translateY(-1px)}.primary-btn.large{padding:15px 27px;font-size:16px}.setup-note{color:var(--muted);font-size:13px}.inline-actions{display:flex;gap:10px;align-items:center;flex-wrap:wrap}
.test-shell{max-width:900px;margin:0 auto}.test-head{display:flex;justify-content:space-between;align-items:center;gap:16px;margin-bottom:20px}.test-meta{display:flex;gap:8px;align-items:center;flex-wrap:wrap}.chip{border:1px solid var(--line);background:#fff;padding:7px 10px;border-radius:999px;font-size:12px;font-weight:800;color:#5f5c57}.chip.red{color:var(--red);border-color:#e7c3c8;background:#fff7f8}.progress-track{height:7px;background:#dfdcd6;border-radius:99px;overflow:hidden;margin-bottom:16px}.progress-track span{height:100%;display:block;background:var(--red);border-radius:99px;transition:width .35s ease}.question-card{background:#fff;border:1px solid var(--line);border-radius:22px;padding:clamp(20px,4vw,38px);box-shadow:var(--shadow);animation:cardIn .28s ease}@keyframes cardIn{from{opacity:0;transform:translateY(8px) scale(.995)}to{opacity:1;transform:none}}.question-top{display:flex;justify-content:space-between;gap:14px;align-items:center}.question-no{font-size:13px;font-weight:900;color:var(--muted)}.question-card h2{font-size:clamp(23px,3vw,34px);line-height:1.18;letter-spacing:-.025em;margin:20px 0}.answer-grid{display:grid;gap:10px;margin-top:24px}.answer{width:100%;border:1px solid var(--line);background:#fbfaf8;border-radius:13px;padding:15px 16px;display:flex;gap:13px;align-items:flex-start;text-align:left;color:var(--ink);transition:.16s ease}.answer:hover:not(:disabled){border-color:#aaa59c;transform:translateX(3px)}.answer .key{width:26px;height:26px;flex:0 0 26px;border-radius:7px;background:#ebe8e2;display:grid;place-items:center;font-size:12px;font-weight:900}.answer.selected{border-color:#7a8793;background:#f1f4f6;box-shadow:inset 0 0 0 1px #7a8793}.answer.selected .key{background:#34495e;color:#fff}.answer.correct{border-color:#9bcbb2;background:#f0faf5}.answer.correct .key{background:var(--green);color:#fff}.answer.wrong{border-color:#e0a0a7;background:#fff2f3}.answer.wrong .key{background:var(--red);color:#fff}.feedback{margin-top:18px;border-left:4px solid var(--green);background:#f3f8f5;padding:14px 16px;border-radius:0 10px 10px 0;line-height:1.55}.feedback.wrong{border-color:var(--red);background:#fff4f5}.question-actions{display:flex;justify-content:space-between;gap:10px;margin-top:22px}.flag-btn.flagged{border-color:#efc26b;background:#fff9ea;color:#7a4d00}
.sign-stage{display:grid;place-items:center;min-height:180px;background:#f2f5f7;border-radius:15px;margin:18px 0 4px;border:1px solid #e0e4e6;overflow:hidden}.sign{filter:drop-shadow(0 8px 8px rgba(0,0,0,.16))}.sign.stop{width:120px;aspect-ratio:1;clip-path:polygon(29% 0,71% 0,100% 29%,100% 71%,71% 100%,29% 100%,0 71%,0 29%);background:#c62433;border:7px solid white;outline:3px solid #c62433;color:white;display:grid;place-items:center;font-size:25px;font-weight:900}.sign.yield{width:0;height:0;border-left:70px solid transparent;border-right:70px solid transparent;border-top:125px solid #d02b39;position:relative}.sign.yield:after{content:"YIELD";position:absolute;top:-103px;left:-53px;width:106px;height:75px;clip-path:polygon(50% 100%,0 0,100% 0);background:white;color:#b3212c;display:grid;place-items:start center;padding-top:20px;font-size:18px;font-weight:900}.sign.diamond{width:104px;height:104px;background:#f4c430;border:4px solid #1d1d1d;transform:rotate(45deg);display:grid;place-items:center}.sign.diamond span{transform:rotate(-45deg);font-size:38px;font-weight:900}.sign.rr{width:116px;height:116px;border-radius:50%;background:#f6df42;border:4px solid #222;display:grid;place-items:center;font-size:28px;font-weight:900;line-height:.85;text-align:center}.sign.speed{width:88px;height:118px;background:white;border:3px solid #222;border-radius:5px;display:grid;place-items:center;text-align:center;font-size:16px;font-weight:900}.sign.speed b{font-size:36px}.sign.no-passing{width:112px;height:112px;background:#f5cf35;clip-path:polygon(50% 0,100% 25%,100% 75%,50% 100%,0 75%,0 25%);display:grid;place-items:center;text-align:center;font-weight:900;font-size:17px;border:0}.sign.oneway{background:white;border:3px solid #222;color:#111;padding:14px 18px;font-weight:900;font-size:20px}.sign.school{width:116px;height:116px;background:#d8f14b;clip-path:polygon(50% 0,94% 32%,78% 100%,22% 100%,6% 32%);display:grid;place-items:center;font-size:38px;border:3px solid #222}.sign.merge{width:104px;height:104px;background:#f4c430;border:4px solid #1d1d1d;transform:rotate(45deg);display:grid;place-items:center}.sign.merge span{transform:rotate(-45deg);font-size:44px}
.results-hero{background:#fff;border:1px solid var(--line);border-radius:24px;padding:32px;box-shadow:var(--shadow);display:grid;grid-template-columns:auto 1fr;gap:28px;align-items:center}.score-ring{width:150px;height:150px;border-radius:50%;display:grid;place-items:center;position:relative;background:conic-gradient(var(--green) var(--score),#e9e6e0 0)}.score-ring:after{content:"";width:118px;height:118px;background:#fff;border-radius:50%;position:absolute}.score-ring span{position:relative;z-index:2;font-size:34px;font-weight:900}.result-copy h1{margin:5px 0 8px;font-size:38px;letter-spacing:-.04em}.result-copy p{color:var(--muted);line-height:1.55}.breakdown{display:grid;grid-template-columns:repeat(4,1fr);gap:10px;margin-top:18px}.break-item{border:1px solid var(--line);border-radius:13px;padding:14px;background:#fff}.break-item small{display:block;color:var(--muted);margin-bottom:6px}.break-item b{font-size:21px}.review-list{display:grid;gap:10px}.review-item{background:#fff;border:1px solid var(--line);border-radius:14px;padding:16px}.review-item h4{margin:0 0 10px;font-size:16px}.review-item p{margin:5px 0;color:var(--muted);font-size:14px;line-height:1.45}.review-item .good{color:var(--green);font-weight:800}.review-item .bad{color:var(--red);font-weight:800}
.study-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:12px}.study-card{background:#fff;border:1px solid var(--line);border-radius:16px;padding:18px;min-height:225px;display:flex;flex-direction:column}.study-card .visual{flex:1;display:grid;place-items:center;min-height:130px}.study-card h3{margin:12px 0 4px}.study-card p{margin:0;color:var(--muted);font-size:14px;line-height:1.45}.history-list{display:grid;gap:10px}.history-row{background:#fff;border:1px solid var(--line);border-radius:14px;padding:16px 18px;display:grid;grid-template-columns:1fr auto auto;gap:16px;align-items:center}.history-row b{display:block}.history-row small{color:var(--muted)}.empty{background:#fff;border:1px dashed #c9c5bd;border-radius:16px;padding:36px;text-align:center;color:var(--muted)}
dialog{width:min(620px,calc(100% - 28px));border:0;border-radius:18px;padding:24px;box-shadow:0 30px 90px rgba(0,0,0,.24)}dialog::backdrop{background:rgba(20,20,20,.45);backdrop-filter:blur(4px)}.dialog-head{display:flex;justify-content:space-between;align-items:start}.dialog-head h2{margin:4px 0 0}.dialog-head small{color:var(--red);font-weight:900;letter-spacing:.12em}.source-list{display:grid;gap:8px}.source-list a{display:flex;justify-content:space-between;gap:10px;text-decoration:none;color:var(--ink);border:1px solid var(--line);padding:13px;border-radius:10px;font-weight:700}.source-list a:hover{border-color:#aaa}
footer{border-top:1px solid var(--line);min-height:58px;padding:14px clamp(18px,4vw,56px);display:flex;align-items:center;justify-content:space-between;gap:12px;color:var(--muted);font-size:12px}footer button{border:0;background:transparent;color:var(--blue);font-weight:800}
@media(max-width:900px){.hero{grid-template-columns:1fr}.difficulty-grid{grid-template-columns:repeat(2,1fr)}.breakdown{grid-template-columns:repeat(2,1fr)}.study-grid{grid-template-columns:repeat(2,1fr)}}
@media(max-width:620px){.topbar{height:72px;padding:10px 16px}.brand small{display:none}.ghost-btn{padding:9px 10px;font-size:12px}main{width:min(100% - 22px,1180px);padding-top:28px}.hero h1{font-size:46px}.lede{font-size:16px}.difficulty-grid{grid-template-columns:1fr}.setup-card{align-items:stretch;flex-direction:column}.mode-seg{display:grid;grid-template-columns:1fr 1fr}.results-hero{grid-template-columns:1fr;text-align:center}.score-ring{margin:auto}.study-grid{grid-template-columns:1fr}.history-row{grid-template-columns:1fr auto}.history-row .date{grid-column:1/-1}.question-card{border-radius:17px}.question-actions{align-items:stretch;flex-direction:column-reverse}.question-actions .primary-btn{width:100%}.breakdown{grid-template-columns:1fr 1fr}footer{flex-direction:column;align-items:flex-start}}
@media(prefers-reduced-motion:reduce){*{animation:none!important;transition:none!important;scroll-behavior:auto!important}}