:root{--bg:#0e0f14;--card:#171923;--line:#262a38;--tx:#eceef6;--mut:#8b91a7;--ac:#6d5efc;--ok:#3ecf8e;--bad:#ff6b6b;--warn:#f5b84a}
@media (prefers-color-scheme:light){:root{--bg:#f6f6fa;--card:#fff;--line:#e2e4ee;--tx:#14151c;--mut:#666c82}}
*{box-sizing:border-box}
body{margin:0;background:var(--bg);color:var(--tx);font:16px/1.45 ui-sans-serif,system-ui,-apple-system,"Segoe UI",sans-serif}
#devbanner{background:var(--warn);color:#241a00;text-align:center;font-size:13px;padding:6px 12px;font-weight:600}
header{display:flex;justify-content:space-between;align-items:center;max-width:720px;margin:0 auto;padding:18px 16px 6px;gap:12px;flex-wrap:wrap}
.logo{font-weight:900;letter-spacing:.12em;font-size:22px}.logo span{color:var(--ac)}
nav{display:flex;gap:6px}
.tab{background:none;border:1px solid var(--line);color:var(--mut);border-radius:999px;padding:6px 14px;cursor:pointer;font:inherit;font-size:14px}
.tab.on{background:var(--ac);border-color:var(--ac);color:#fff}
main{max-width:720px;margin:0 auto;padding:8px 16px 60px}
.rounds{display:flex;gap:8px;margin:10px 0 18px}
.rounds button{flex:1;padding:9px 0;border-radius:10px;border:1px solid var(--line);background:var(--card);color:var(--mut);cursor:pointer;font:inherit;font-weight:700}
.rounds button.on{border-color:var(--ac);color:var(--tx)}
.rounds button.done{background:color-mix(in srgb,var(--ok) 18%,var(--card));color:var(--ok);border-color:transparent}
.meta{color:var(--mut);font-size:13px;letter-spacing:.1em;text-transform:uppercase;margin-bottom:10px}
.endpoints{display:flex;align-items:center;justify-content:space-between;gap:10px;background:var(--card);border:1px solid var(--line);border-radius:16px;padding:18px 20px}
.endpoints small{color:var(--mut);letter-spacing:.14em;font-size:11px}
.endpoints h1{margin:2px 0 0;font-size:clamp(26px,7vw,42px);letter-spacing:.04em;word-break:break-word}
.to{color:var(--ac);font-size:28px}
.chain{list-style:none;margin:18px 0 8px;padding:0;display:flex;flex-direction:column;gap:0}
.chain li{position:relative;padding:10px 14px;border:1px solid var(--line);background:var(--card);border-radius:10px;text-transform:uppercase;letter-spacing:.06em;font-weight:700;margin-bottom:14px}
.chain li:not(:last-child)::after{content:"";position:absolute;left:24px;bottom:-14px;height:14px;width:2px;background:var(--ac)}
.chain li.start{border-color:var(--ac)}
.chain li .why{display:block;text-transform:none;letter-spacing:0;font-weight:400;color:var(--mut);font-size:12px}
.chain li.unv{border-style:dashed}
form{display:flex;gap:8px}
input{flex:1;min-width:0;background:var(--card);border:1px solid var(--line);color:var(--tx);padding:12px 14px;border-radius:10px;font:inherit;font-size:17px;text-transform:uppercase;letter-spacing:.05em}
input:focus{outline:2px solid var(--ac);border-color:transparent}
button.primary{background:var(--ac);color:#fff;border:0;border-radius:10px;padding:0 18px;font:inherit;font-weight:700;cursor:pointer;min-height:44px}
button.primary:disabled{opacity:.5;cursor:wait}
button.ghost{background:none;border:1px solid var(--line);color:var(--tx);border-radius:10px;padding:8px 14px;font:inherit;cursor:pointer}
button:hover:not(:disabled){filter:brightness(1.1)}
.msg{min-height:24px;margin:8px 2px;font-size:14px}
.msg.bad{color:var(--bad)}.msg.ok{color:var(--ok)}
.msg a{color:var(--ac);cursor:pointer;text-decoration:underline;margin-left:6px}
.row{display:flex;gap:8px;align-items:center;flex-wrap:wrap;margin-top:10px}
#count{margin-right:auto;color:var(--mut)}
.hint,.muted{color:var(--mut);font-size:13px}
.arrow{align-self:center;color:var(--ac)}
#custom-form{margin-top:10px}
#result{background:var(--card);border:1px solid var(--line);border-radius:16px;padding:22px;margin-top:20px}
.grade{color:var(--ac);font-weight:800;letter-spacing:.12em;text-transform:uppercase;font-size:13px}
.big{font-size:44px;font-weight:900;margin:2px 0 12px}
.route{display:flex;flex-wrap:wrap;gap:6px;align-items:center;margin:6px 0}
.route b{background:var(--bg);border:1px solid var(--line);padding:3px 9px;border-radius:7px;text-transform:uppercase;font-size:13px;letter-spacing:.05em}
.route i{color:var(--ac);font-style:normal}
#community{margin:16px 0;border-top:1px solid var(--line);padding-top:12px}
#community h3{margin:0 0 4px;font-size:12px;letter-spacing:.12em;color:var(--mut);text-transform:uppercase}
#community .blk{margin-bottom:12px}
[hidden]{display:none!important}