:root { --bg: #12151b; --card: #1b2029; --line: #2a313d; --fg: #e3e7ee; --dim: #8c96a6; --acc: #4f9dff; --bad: #e5534b; }
* { box-sizing: border-box; }
body { margin: 0; min-height: 100vh; display: grid; place-items: center; color: var(--fg); font: 14px/1.45 system-ui, sans-serif;
  background: radial-gradient(900px 500px at 20% -10%, #1a2740 0%, transparent 60%), var(--bg); }
.box { width: min(360px, 92vw); background: var(--card); border: 1px solid var(--line); border-radius: 12px; padding: 26px 26px 22px;
  box-shadow: 0 20px 60px #0007; }
h1 { font-size: 19px; margin: 0 0 18px; text-align: center; }
label { display: block; color: var(--dim); font-size: 12px; margin: 12px 0 0; }
input { width: 100%; margin-top: 4px; background: #0f1217; color: var(--fg); border: 1px solid var(--line); border-radius: 6px;
  padding: 9px 10px; font: inherit; }
input:focus { outline: none; border-color: var(--acc); }
button { width: 100%; margin-top: 20px; padding: 10px; border: 0; border-radius: 8px; font: inherit; font-weight: 600; color: #fff;
  cursor: pointer; background: linear-gradient(135deg, #4f9dff, #7b6cff); }
.err { background: #3a1d20; border: 1px solid #6b2b2f; color: #ffb3ae; border-radius: 6px; padding: 7px 10px; font-size: 13px; }
.hidden { display: none; }
.hint { color: var(--dim); font-size: 12px; background: #0f1217; border-radius: 6px; padding: 8px 10px; }
.hint code { color: var(--fg); font-size: 11px; word-break: break-all; }