:root{--bg:#F5F6F8;--panel:#FFFFFF;--ink:#18202E;--muted:#5E6878;--line:#DDE2E9;--acc:#B3541E;--accHover:#9C4718;--accInk:#FFFFFF;--err:#B42318;color-scheme:light dark}@media (prefers-color-scheme:dark){:root{--bg:#10151F;--panel:#171E2B;--ink:#E6EBF2;--muted:#9BA6B7;--line:#2B3446;--acc:#E8894F;--accHover:#F0A574;--accInk:#1A0F08;--err:#F08A80}}body{margin:0;min-height:100vh;display:grid;place-items:center;background:var(--bg);color:var(--ink);font-family:'IBM Plex Sans',system-ui,'Segoe UI',Arial,sans-serif}.box{background:var(--panel);border:1px solid var(--line);border-radius:12px;padding:28px;width:min(360px,calc(100vw - 32px));box-shadow:0 1px 2px rgba(24,32,46,.06),0 4px 16px rgba(24,32,46,.06)}h1{margin:8px 0 4px;font-size:24px}p{color:var(--muted)}.err{color:var(--err);font-weight:600}form{display:grid;gap:8px;margin-top:12px}input{font:inherit;font-size:18px;letter-spacing:.08em;padding:10px;border:1px solid var(--line);border-radius:8px;background:var(--panel);color:var(--ink)}input:focus-visible,button:focus-visible{outline:2px solid var(--acc);outline-offset:2px}button{font:inherit;font-weight:700;min-height:44px;border:0;border-radius:8px;background:var(--acc);color:var(--accInk);cursor:pointer}button:hover{background:var(--accHover)}