:root{--paper:#161616;--surface:#1E1E1E;--ink:#F7F7F7;--muted:#A4A4A4;--rule:#2C2C2C;--accent:#2BC4C4;}
  *{box-sizing:border-box;margin:0;padding:0;}
  html,body{background:var(--paper);}
  body{color:var(--ink);font-family:"IBM Plex Sans",-apple-system,"Segoe UI",Roboto,Arial,sans-serif;
       font-size:17px;line-height:1.6;min-height:100vh;display:flex;align-items:center;justify-content:center;padding:32px;}
  .card{max-width:560px;width:100%;}
  .eyebrow{font-family:ui-monospace,Consolas,monospace;font-size:11px;font-weight:600;
           letter-spacing:.2em;text-transform:uppercase;color:var(--accent);margin-bottom:16px;}
  h1{font-size:30px;line-height:1.15;letter-spacing:-.02em;margin-bottom:14px;font-weight:700;}
  p{color:var(--muted);margin-bottom:14px;}
  .file{font-family:ui-monospace,Consolas,monospace;font-size:14px;background:var(--surface);
        border:1px solid var(--rule);padding:12px 14px;margin:18px 0;word-break:break-all;color:var(--ink);}
  a.btn{display:inline-block;background:var(--accent);color:#001C24;font-weight:600;
        padding:13px 24px;text-decoration:none;border:1.5px solid var(--accent);margin-right:10px;}
  a.btn:hover{background:#7FD9DC;border-color:#7FD9DC;}
  a.btn[hidden]{display:none;}
  a.back{color:var(--accent);font-size:15px;}
  .err{color:#E7A948;}