:root{color-scheme:dark;--bg:#080a0d;--card:#15191f;--layer:#0e1217;--line:#29313a;--text:#f5f7fa;--muted:#97a3b3;--cyan:#16d7ff;--purple:#ae3bff;--green:#42e6b2;font:16px/1.55 "Segoe UI Variable",Segoe UI,sans-serif}
*{box-sizing:border-box}body{margin:0;min-height:100vh;color:var(--text);background:radial-gradient(circle at 20% -10%,#11364c 0,transparent 35%),radial-gradient(circle at 90% 0,#321446 0,transparent 32%),var(--bg)}
.page{width:min(940px,calc(100% - 36px));margin:auto;padding:32px 0 60px}.brand{display:flex;align-items:center;gap:12px}.brand-mark{display:grid;place-items:center;width:46px;height:46px;border-radius:14px;font-weight:900;background:linear-gradient(135deg,var(--cyan),#2877ff,var(--purple));box-shadow:0 8px 28px #135f8d55}.brand strong,.brand small{display:block}.brand small{color:var(--muted);font-size:12px}
.hero{text-align:center;padding:70px 12px 36px}.eyebrow{color:var(--cyan);font-size:12px;font-weight:800;letter-spacing:.15em}.hero h1{margin:12px 0 8px;font-size:clamp(34px,6vw,58px);line-height:1.12}.hero p{margin:0;color:var(--muted);font-size:18px}
.card{padding:28px;border:1px solid var(--line);border-radius:22px;background:linear-gradient(145deg,#181d24ee,#11151aee);box-shadow:0 22px 70px #0007}label{display:block;margin-bottom:9px;font-weight:700}.code-row{display:grid;grid-template-columns:1fr auto;gap:12px}input,button{font:inherit;border-radius:11px}input{min-width:0;padding:16px 18px;border:1px solid var(--line);outline:0;background:var(--layer);color:var(--text);font:700 21px/1.2 Consolas,monospace;letter-spacing:.09em;text-transform:uppercase}input:focus{border-color:var(--cyan);box-shadow:0 0 0 3px #16d7ff22}button{border:0;padding:14px 24px;color:white;font-weight:800;cursor:pointer;background:linear-gradient(120deg,var(--cyan),#3d83ff,var(--purple))}button:disabled{opacity:.55;cursor:wait}.help{margin:11px 0 0;color:var(--muted);font-size:13px}.help b{color:#cfd8e4;font-family:Consolas,monospace}
.result{margin-top:22px;padding:22px;border:1px solid #1f765f;border-radius:14px;background:#0c2924}.result span{display:block;color:var(--green);font-weight:800}.result strong{display:block;margin:10px 0 5px;font:800 clamp(18px,4vw,28px)/1.3 Consolas,monospace;overflow-wrap:anywhere}.result p{margin:0 0 16px;color:#b5d7ce}.result button{background:#1d6957}.error{margin-top:18px;padding:14px 16px;border:1px solid #8c3441;border-radius:11px;background:#361820;color:#ffc4ca}
.rules{display:grid;grid-template-columns:repeat(3,1fr);gap:14px;margin-top:18px}.rules article{display:flex;gap:13px;padding:20px;border:1px solid var(--line);border-radius:16px;background:#11151a}.rules article>span{display:grid;place-items:center;flex:0 0 36px;height:36px;border-radius:10px;color:var(--cyan);background:#0b2f3a;font-weight:800}.rules h2{margin:0;font-size:16px}.rules p{margin:5px 0;color:var(--muted);font-size:13px}.rules a{color:var(--cyan);text-decoration:none;font-weight:700}
@media(max-width:720px){.hero{padding-top:52px}.card{padding:20px}.code-row{grid-template-columns:1fr}.rules{grid-template-columns:1fr}}