:root{color-scheme:light;--ink:#152e40;--muted:#536878;--teal:#086d6d;--paper:#f8faf7;--lime:#def484}*{box-sizing:border-box}body{margin:0;background:var(--paper);color:var(--ink);font:17px/1.6 system-ui,-apple-system,"Segoe UI",sans-serif}a{color:inherit}header{max-width:1250px;margin:auto;padding:28px 36px;display:flex;justify-content:space-between;align-items:center;gap:20px}.brand{font-weight:850;font-size:25px;letter-spacing:-1px;text-decoration:none}.brand>span:first-child{font-weight:450}.brand-dot{color:var(--teal)}.teacher-link{font-size:14px;font-weight:650;text-decoration:none;border-bottom:1px solid #a3b3b6;padding-bottom:3px}main{position:relative;overflow:hidden;min-height:calc(100svh - 175px);display:grid;place-items:center;padding:44px 20px 55px}.hero{position:relative;z-index:1;max-width:680px;width:100%;text-align:center}.eyebrow{display:inline-flex;gap:12px;align-items:center;font-size:12px;font-weight:800;letter-spacing:2px;margin:0 0 24px}.eyebrow span{color:var(--teal);font-size:25px}h1{font-size:clamp(44px,7.5vw,83px);font-weight:850;letter-spacing:-3.7px;line-height:1.04;margin:0 0 24px}h1>span{background:linear-gradient(transparent 63%,var(--lime) 63%);padding:0 8px}.intro{color:var(--muted);font-size:18px;margin:0 0 35px}.code-card{position:relative;background:white;border:1px solid #dce6df;border-radius:24px;box-shadow:0 18px 60px #152e4009;padding:30px 34px;margin:auto;max-width:510px;text-align:left}.code-card label{font-size:17px;font-weight:750}.hint{font-size:13px;color:var(--muted);margin:5px 0 14px}.code-card input{width:100%;height:80px;border:2px solid #ccd9d1;background:#fafcf9;border-radius:12px;color:var(--ink);font:650 32px/1.2 ui-monospace,monospace;text-align:center;letter-spacing:7px;padding:12px;scroll-margin:20px}.code-card input::placeholder{color:#718278;opacity:1}.code-card button{display:flex;align-items:center;justify-content:center;gap:15px;width:100%;min-height:58px;margin-top:15px;border:0;border-radius:12px;background:var(--teal);color:white;font:750 17px/1.4 system-ui,sans-serif;cursor:pointer}.code-card button:hover{background:#075b5b}.code-card input:focus{border-color:var(--teal)}:focus-visible{outline:3px solid #dd9632;outline-offset:4px}.privacy{color:var(--muted);font-size:12px;margin:20px 0 0;text-align:center}.privacy span{color:var(--teal);font-weight:800}.error{margin:18px 0 0;padding:13px 15px;border-left:4px solid #ac3f36;border-radius:5px;background:#fff0ed;color:#8b2e27;font-size:15px}.next{font-size:13px;color:var(--muted);margin:25px 0 0}.orbit{position:absolute;border:1px solid #d5e2d4;border-radius:50%;width:320px;height:320px;pointer-events:none}.orbit-one{left:-195px;top:18%;box-shadow:0 0 0 45px #f8faf7,0 0 0 46px #e0e9da}.orbit-two{right:-205px;bottom:15%;border-color:#c2d5d5;background:#ecf3ec}footer{text-align:center;color:var(--muted);font-size:12px;padding:20px}@media(max-width:600px){header{padding:22px 20px}.brand{font-size:21px}.teacher-link{font-size:12px}main{padding:36px 16px 38px;min-height:auto}h1{letter-spacing:-2.3px}.intro{font-size:16px;margin-bottom:26px}.code-card{padding:25px 22px;border-radius:20px}.code-card input{font-size:29px;letter-spacing:5px;height:74px}.privacy{font-size:11px}.orbit{opacity:.5}.eyebrow{font-size:10px;letter-spacing:1.5px;margin-bottom:20px}}@media(prefers-reduced-motion:reduce){*{scroll-behavior:auto}}