:root{color-scheme:dark;--bg:#0b0f14;--panel:#151e27;--line:#293745;--text:#f5f8fa;--muted:#b5c3ce;--accent:#52f5a5;--accent-dark:#062116}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;background:radial-gradient(circle at 75% 0,#174131 0,transparent 36rem),var(--bg);color:var(--text);font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,"Noto Sans KR",sans-serif;line-height:1.65}
a{color:inherit;text-underline-offset:4px}
a:focus-visible{outline:3px solid var(--accent);outline-offset:4px}
.wrap{width:min(1120px,calc(100% - 36px));margin:auto}
.topbar{display:flex;align-items:center;justify-content:space-between;gap:20px;padding:24px 0}
.brand{display:flex;align-items:center;gap:10px;color:var(--accent);font-size:.9rem;font-weight:900;letter-spacing:.1em;text-decoration:none}
.brand-mark{display:grid;place-items:center;width:34px;height:34px;border-radius:11px;background:var(--accent);color:var(--accent-dark);font-size:1.1rem;letter-spacing:0}
.topbar nav{display:flex;gap:22px;align-items:center;font-size:.9rem;font-weight:700}
.topbar nav a{text-decoration:none}
.topbar nav a:hover,.footer a:hover{text-decoration:underline}
.hero{display:grid;grid-template-columns:minmax(0,1.2fr) minmax(300px,.8fr);gap:50px;align-items:center;padding:80px 0 96px}
.eyebrow{margin:0 0 18px;color:var(--accent);font-size:.82rem;font-weight:900;letter-spacing:.13em;text-transform:uppercase}
h1{max-width:780px;margin:0;font-size:clamp(2.6rem,6.5vw,5.5rem);line-height:1.12;letter-spacing:-.06em}
.lead{max-width:620px;margin:25px 0 0;color:var(--muted);font-size:clamp(1rem,1.8vw,1.2rem)}
.actions{display:flex;flex-wrap:wrap;gap:12px;margin-top:32px}
.button{display:inline-flex;align-items:center;justify-content:center;min-height:52px;padding:12px 22px;border:1px solid var(--line);border-radius:14px;font-weight:850;text-decoration:none}
.button.primary{background:var(--accent);color:var(--accent-dark);border-color:var(--accent)}
.button:hover{transform:translateY(-2px)}
.hero-card{position:relative;padding:24px;border:1px solid #365444;border-radius:30px;background:linear-gradient(145deg,#1b352b,#131c25 68%);box-shadow:0 28px 80px #0006}
.hero-card:before{content:"";display:block;position:absolute;inset:15px;border:1px solid #ffffff12;border-radius:20px;pointer-events:none}
.screen-label{color:#a8cdb7;font-size:.8rem;font-weight:800;letter-spacing:.12em;text-transform:uppercase}
.score{margin:30px 0 7px;font-size:clamp(4.2rem,10vw,6rem);font-weight:950;line-height:1;color:var(--accent);font-variant-numeric:tabular-nums}
.score-sub{color:#c7d8cd;font-weight:700}
.equation{margin:36px 0 19px;padding:18px;border:1px solid #395447;border-radius:17px;background:#0d2019;text-align:center;font-size:2rem;font-weight:900}
.choices{display:grid;grid-template-columns:repeat(2,1fr);gap:10px}
.choices span{display:grid;place-items:center;min-height:54px;border:1px solid #385247;border-radius:13px;background:#1c352a;font-size:1.1rem;font-weight:850}
.choices span:nth-child(3){border-color:var(--accent);background:#285942;color:var(--accent)}
section.content{padding:74px 0;border-top:1px solid var(--line)}
section.content h2{max-width:760px;margin:0 0 16px;font-size:clamp(1.8rem,3.7vw,3rem);line-height:1.25;letter-spacing:-.045em}
section.content>.intro{max-width:760px;margin:0 0 28px;color:var(--muted)}
.grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:14px;margin-top:28px}
.tile{padding:25px;border:1px solid var(--line);border-radius:20px;background:var(--panel)}
.tile .num{color:var(--accent);font-size:.8rem;font-weight:900;letter-spacing:.1em}
.tile h3{margin:9px 0 7px;font-size:1.23rem;line-height:1.3}
.tile p{margin:0;color:var(--muted);font-size:.95rem}
.modes{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:11px;padding:0;margin:28px 0 0;list-style:none}
.modes li{padding:16px 19px;border:1px solid var(--line);border-radius:14px;background:#101820;font-weight:750}
.cta{margin:40px 0 70px;padding:35px;border:1px solid #375c49;border-radius:25px;background:linear-gradient(110deg,#18382a,#14202a)}
.cta h2{margin:0 0 8px;font-size:clamp(1.6rem,3vw,2.5rem);letter-spacing:-.04em}
.cta p{margin:0;color:var(--muted)}
.cta .actions{margin-top:22px}
.footer{display:flex;justify-content:space-between;gap:18px;flex-wrap:wrap;padding:25px 0 38px;border-top:1px solid var(--line);color:#99aab6;font-size:.86rem}
.footer nav{display:flex;gap:18px;flex-wrap:wrap}
@media(max-width:800px){.hero{grid-template-columns:1fr;padding:54px 0 65px}.hero-card{width:min(100%,450px)}.grid,.modes{grid-template-columns:repeat(2,minmax(0,1fr))}}
@media(max-width:550px){.topbar nav{gap:12px;font-size:.8rem}.hero{gap:38px}.grid,.modes{grid-template-columns:1fr}section.content{padding:56px 0}.cta{padding:25px}.footer{display:block}.footer nav{margin-top:12px}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}.button:hover{transform:none}}