*{box-sizing:border-box}html,body{height:100%}body{margin:0;font-family:system-ui,-apple-system,Segoe UI,Roboto,Ubuntu;line-height:1.5;background:#0b1220;color:#e5e7eb}
.container{max-width:860px;margin:0 auto;padding:24px}
h1{font-size:clamp(28px,3.2vw,42px);margin:0 0 16px}
.card{background:#111827;border:1px solid #374151;border-radius:16px;padding:16px;margin:16px 0;box-shadow:0 6px 16px rgba(0,0,0,.25)}
button{appearance:none;border:0;border-radius:12px;padding:10px 14px;font-weight:600;background:#2563eb;color:#fff;cursor:pointer}
button:hover{filter:brightness(1.1)}
pre{white-space:pre-wrap;background:#0f172a;color:#93c5fd;padding:12px;border-radius:12px}
dialog{border:0;border-radius:16px;padding:16px;max-width:420px}