:root { --bg: #f7f6f3; --panel: #fff; --text: #1d1f24; --muted: #6b6f78; --line: #e4e2dc; --accent: #e0502f; color-scheme: light; }
@media (prefers-color-scheme: dark) {
  :root { --bg: #11131a; --panel: #181b24; --text: #e6e7eb; --muted: #959aa6; --line: #2a2e3a; --accent: #f26d4f; color-scheme: dark; }
}
* { box-sizing: border-box; }
body { margin: 0; min-height: 100vh; display: grid; place-items: center; padding: 16px; background: var(--bg); color: var(--text); font: 16px/1.5 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif; }
.box { width: 100%; max-width: 340px; padding: 28px 24px; background: var(--panel); border: 1px solid var(--line); border-radius: 16px; text-align: center; }
h1 { font-size: 22px; margin: 0 0 8px; }
.hint { color: var(--muted); font-size: 14px; margin: 0 0 16px; }
a { color: var(--accent); }
form { display: grid; gap: 10px; margin-top: 12px; }
input { width: 100%; height: 52px; text-align: center; font: 600 26px/1 ui-monospace, Consolas, monospace; letter-spacing: .4em; border: 1px solid var(--line); border-radius: 12px; background: var(--bg); color: var(--text); outline: 0; }
input:focus { border-color: var(--accent); }
input::placeholder { color: var(--muted); letter-spacing: .3em; }
button { height: 46px; border: 0; border-radius: 12px; background: var(--accent); color: #fff; font: 600 16px system-ui, sans-serif; cursor: pointer; }
.error { color: var(--accent); font-size: 14px; margin: 4px 0 0; }