:root{--bg:#080914;--panel:#111326;--panel2:#171a31;--text:#f7f7ff;--muted:#a9acc6;--purple:#8b5cf6;--blue:#4f8cff;--green:#41d69b;--red:#ff667d;--line:#292d4c}*{box-sizing:border-box}body{margin:0;background:radial-gradient(circle at 80% 0,#1c1742 0,transparent 35%),var(--bg);color:var(--text);font-family:Poppins,Arial,sans-serif;min-height:100vh}.shell{width:min(920px,92%);margin:auto;padding:52px 0 80px}.screen{display:none}.screen.active{display:block}.eyebrow{font-size:.78rem;letter-spacing:.18em;font-weight:700;color:#bca8ff;margin-bottom:12px}h1{font-size:clamp(2.5rem,8vw,5rem);line-height:.95;margin:0 0 20px;font-weight:800}h1 span{color:#9b78ff}.lead{color:var(--muted);font-size:1.08rem;max-width:720px;line-height:1.75}.video{margin:32px 0;border:1px solid var(--line);border-radius:22px;overflow:hidden;background:#000;box-shadow:0 20px 70px #0007}.video video{width:100%;display:block;max-height:520px}.card,.question-card,.form{background:linear-gradient(145deg,#12152a,#0e1020);border:1px solid var(--line);border-radius:22px;padding:28px;margin:24px 0}.tutorial h2,.card h2{margin-top:0}.versus{display:grid;grid-template-columns:1fr 1fr;gap:14px;margin:22px 0}.versus div{background:var(--panel2);padding:18px;border-radius:15px}.versus small{display:block;color:var(--muted);margin-bottom:8px}.versus strong{font-size:1rem;line-height:1.7}.example{padding:16px;border-left:3px solid var(--purple);background:#17152b;border-radius:8px}.example em{color:#bda8ff;font-style:normal;font-weight:800}.primary{border:0;border-radius:14px;padding:16px 24px;background:linear-gradient(100deg,var(--purple),var(--blue));color:white;font:700 1rem Poppins;cursor:pointer;display:inline-block;text-decoration:none}.primary:hover{filter:brightness(1.08);transform:translateY(-1px)}.topbar{display:flex;justify-content:space-between;font-weight:700;color:#c8c9db;margin-bottom:10px}.progress{height:7px;background:#1d2038;border-radius:99px;overflow:hidden;margin-bottom:24px}.progress i{display:block;height:100%;width:5%;background:linear-gradient(90deg,var(--purple),var(--blue));transition:.3s}.question-card{padding:34px}.context{color:#b7b9cf;line-height:1.7}.question-card h2{font-size:clamp(1.35rem,3vw,2rem);line-height:1.5}.answers{display:grid;gap:12px;margin:25px 0}.answer{background:#181b32;border:1px solid #303451;color:white;border-radius:14px;padding:16px 18px;text-align:left;font:500 1rem Poppins;cursor:pointer}.answer:hover{border-color:#7562c8}.answer.correct{border-color:var(--green);background:#103128}.answer.wrong{border-color:var(--red);background:#36151e}.answer:disabled{cursor:default}.feedback{padding:16px 18px;border-radius:14px;background:#171a31;color:#d8d9e7;line-height:1.65;margin-bottom:18px}.boss{display:inline-block;background:#351548;color:#f0b5ff;border:1px solid #7c3b92;border-radius:999px;padding:7px 12px;font-size:.78rem;font-weight:800;letter-spacing:.08em}.hidden{display:none!important}.form{display:grid;gap:18px}.form label{display:grid;gap:8px;font-weight:600}.form input,.form textarea{width:100%;background:#0a0c19;border:1px solid #323653;color:white;border-radius:12px;padding:14px;font:500 1rem Poppins}.form textarea{min-height:170px;resize:vertical}.teacher-note{background:#17152c;border-left:3px solid var(--purple);padding:18px;border-radius:10px;color:#d5d5e5}.teacher-note p{margin-bottom:0}.consent{grid-template-columns:auto 1fr!important;align-items:start;font-weight:400!important;color:#c0c2d4;font-size:.9rem}.consent input{width:auto;margin-top:4px}.error{color:#ff91a3}.unlock{font-weight:800;color:var(--green);letter-spacing:.08em;margin-bottom:14px}.result-card{font-size:1.05rem;line-height:1.7}.run{display:flex;gap:8px;flex-wrap:wrap}.run button{width:43px;height:43px;border-radius:10px;border:1px solid var(--line);background:#171a31;color:white;cursor:pointer}.run button.ok{border-color:#267e61}.run button.no{border-color:#9e3546}.review{margin-top:18px}.review-item{border-top:1px solid var(--line);padding:16px 0;color:#d8d9e7}.review-item b{color:white}.cta{text-align:center}.link{margin-top:8px}@media(max-width:650px){.shell{padding-top:30px}.versus{grid-template-columns:1fr}.question-card,.card,.form{padding:21px}h1{font-size:2.7rem}}