:root{
  --bg:#f6f8fb;--surface:#fff;--ink:#162033;--muted:#657084;--line:#e5eaf1;
  --physics:#2f6feb;--chem:#2f9e5b;--bio:#168b86;--radius:22px;
}
*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;background:var(--bg);color:var(--ink);line-height:1.55}a{color:inherit}.wrap{width:min(1120px,calc(100% - 32px));margin:auto}.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}.site-header{position:sticky;top:0;z-index:10;background:rgba(246,248,251,.92);backdrop-filter:blur(12px);border-bottom:1px solid rgba(229,234,241,.85)}.nav{min-height:68px;display:flex;align-items:center;justify-content:space-between;gap:22px}.brand{display:flex;align-items:center;gap:10px;text-decoration:none;font-weight:800;white-space:nowrap}.brand-mark{display:grid;place-items:center;width:34px;height:34px;border-radius:10px;background:#172033;color:#fff}.hub-nav{display:flex;gap:6px 18px;align-items:center;flex-wrap:wrap;justify-content:flex-end}.hub-nav a{text-decoration:none;color:var(--muted);font-weight:700;font-size:.9rem}.hub-nav a:hover{color:var(--ink);text-decoration:underline}.hero{padding:82px 0 58px;text-align:center}.eyebrow{margin:0 0 10px;font-size:.78rem;text-transform:uppercase;letter-spacing:.14em;font-weight:800;color:#778399}.hero h1{font-size:clamp(2.4rem,6vw,5rem);line-height:1.03;letter-spacing:-.045em;max-width:900px;margin:0 auto 22px}.lede{max-width:790px;margin:0 auto 30px;color:var(--muted);font-size:1.12rem}.hero-actions{display:flex;justify-content:center;gap:10px;flex-wrap:wrap}.primary,.secondary,.button-like{display:inline-block;text-decoration:none;font-weight:800;padding:12px 18px;border-radius:999px;min-height:46px}.primary{background:#172033;color:#fff;border:1px solid #172033}.secondary,.button-like{background:#fff;color:#172033;border:1px solid #cfd7e3}.button-like{font:inherit;cursor:pointer}.primary:hover{background:#29364d}.secondary:hover,.button-like:hover{border-color:#8392a7;background:#fbfcfe}.search-section{scroll-margin-top:90px;padding:24px 0 58px}.section-head{text-align:center;margin-bottom:28px}.section-head.compact{max-width:760px;margin-left:auto;margin-right:auto}.section-head h2,.how h2,.about-project h2,.feedback h2{margin:0;font-size:clamp(1.8rem,4vw,3rem);letter-spacing:-.03em}.section-head p:not(.eyebrow){color:var(--muted);margin:12px auto 0}.search-box{position:relative;max-width:820px;margin:0 auto}.search-box input{width:100%;border:1px solid #cbd5e1;border-radius:18px;background:#fff;color:var(--ink);font:inherit;font-size:1.05rem;padding:17px 58px 17px 18px;box-shadow:0 16px 38px rgba(22,32,51,.07);outline:none}.search-box input:focus{border-color:#65748d;box-shadow:0 0 0 3px rgba(47,111,235,.12),0 16px 38px rgba(22,32,51,.07)}.search-shortcut{position:absolute;right:17px;top:50%;transform:translateY(-50%);border:1px solid var(--line);background:#f8fafc;color:var(--muted);border-radius:7px;padding:2px 8px;font-weight:800}.search-chips{display:flex;justify-content:center;flex-wrap:wrap;gap:8px;margin:14px auto 0}.search-chips button{border:1px solid var(--line);background:#fff;border-radius:999px;padding:7px 12px;color:var(--muted);font:inherit;font-size:.84rem;cursor:pointer}.search-chips button:hover{border-color:#9aa8bb;color:var(--ink)}.search-status{max-width:820px;margin:14px auto 10px;color:var(--muted);font-size:.88rem}.search-results{max-width:820px;margin:auto;display:grid;grid-template-columns:1fr 1fr;gap:10px}.search-result{display:flex;flex-direction:column;gap:5px;text-decoration:none;background:#fff;border:1px solid var(--line);border-radius:14px;padding:15px;min-width:0}.search-result:hover{border-color:#a7b4c5;box-shadow:0 8px 20px rgba(22,32,51,.06)}.search-result strong{line-height:1.3}.search-result>span:last-child{color:var(--muted);font-size:.84rem}.search-subject{font-size:.72rem;font-weight:800;text-transform:uppercase;letter-spacing:.08em}.search-subject.physics{color:var(--physics)}.search-subject.chemistry{color:var(--chem)}.search-subject.biology{color:var(--bio)}.subjects{scroll-margin-top:90px;padding:36px 0 76px}.cards{display:grid;grid-template-columns:repeat(3,1fr);gap:20px}.subject-card{position:relative;overflow:hidden;display:flex;flex-direction:column;gap:24px;min-height:440px;padding:28px;border-radius:var(--radius);background:var(--surface);border:1px solid var(--line);text-decoration:none;box-shadow:0 18px 45px rgba(22,32,51,.06);transition:transform .18s ease,box-shadow .18s ease,border-color .18s ease}.subject-card:hover{transform:translateY(-5px);box-shadow:0 24px 55px rgba(22,32,51,.11)}.subject-card::after{content:"";position:absolute;right:-55px;top:-55px;width:190px;height:190px;border-radius:50%;opacity:.07;background:currentColor}.physics{color:var(--physics)}.chemistry{color:var(--chem)}.biology{color:var(--bio)}.subject-card>div:last-child{color:var(--ink)}.icon-wrap{width:86px;height:86px;border-radius:22px;background:color-mix(in srgb,currentColor 10%,white);display:grid;place-items:center;color:inherit}.icon-wrap svg{width:54px;height:54px}.kicker{display:inline-block;color:inherit;font-weight:800;font-size:.82rem;text-transform:uppercase;letter-spacing:.12em}.subject-card h3{font-size:1.62rem;line-height:1.15;margin:8px 0 12px;letter-spacing:-.02em}.subject-card p{color:var(--muted);margin:0 0 28px}.cta{font-weight:800;color:inherit}.about-project{scroll-margin-top:90px;padding:24px 0 72px}.about-project>div:first-child{text-align:center;max-width:820px;margin:0 auto 26px}.about-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:18px}.about-grid article,.how-grid article{background:#fff;border:1px solid var(--line);border-radius:18px;padding:24px}.about-grid h3{margin:0 0 8px}.about-grid p{color:var(--muted);margin:0}.how{padding:20px 0 82px}.how>div:first-child{text-align:center;margin-bottom:28px}.how-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:18px}.how-grid strong{display:grid;place-items:center;width:34px;height:34px;border-radius:999px;background:#172033;color:#fff}.how-grid h3{margin:16px 0 8px}.how-grid p{margin:0;color:var(--muted)}.updates{scroll-margin-top:90px;padding:16px 0 76px}.timeline{list-style:none;padding:0;margin:0 auto;max-width:880px;border-top:1px solid var(--line)}.timeline li{display:grid;grid-template-columns:130px 1fr;gap:24px;padding:22px 0;border-bottom:1px solid var(--line)}.timeline time{font-size:.85rem;color:var(--muted);font-weight:700}.timeline strong{display:block;margin-bottom:5px}.timeline p{margin:0;color:var(--muted)}.feedback{scroll-margin-top:90px;display:grid;grid-template-columns:1.4fr 1fr;gap:30px;align-items:start;padding:18px 0 86px}.feedback>div:first-child p:not(.eyebrow){color:var(--muted);max-width:700px}.feedback-actions{background:#fff;border:1px solid var(--line);border-radius:18px;padding:22px;display:flex;flex-direction:column;align-items:flex-start;gap:10px}.feedback-status{font-size:.84rem;color:var(--muted);margin:4px 0 0}.feedback-note{font-size:.84rem;color:var(--muted);margin:0}footer{border-top:1px solid var(--line);background:#fff}.footer-inner{min-height:90px;display:flex;justify-content:space-between;align-items:center;color:var(--muted);font-size:.92rem}
@media(max-width:850px){.nav{align-items:flex-start;padding:14px 0;flex-direction:column;gap:8px}.hub-nav{justify-content:flex-start}.cards,.how-grid,.about-grid{grid-template-columns:1fr}.subject-card{min-height:0}.search-results{grid-template-columns:1fr}.feedback{grid-template-columns:1fr}.footer-inner{flex-direction:column;justify-content:center;gap:4px;text-align:center}}
@media(max-width:520px){.hero{padding-top:55px}.wrap{width:min(100% - 22px,1120px)}.subject-card{padding:22px}.icon-wrap{width:74px;height:74px}.hub-nav{gap:4px 12px}.hub-nav a{font-size:.82rem}.timeline li{grid-template-columns:1fr;gap:5px}.search-shortcut{display:none}.search-box input{padding-right:18px}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}.subject-card{transition:none}}