:root { color-scheme: light dark; --bg: #f6f8f4; --fg: #1d2a1f; --muted: #5b6b5e; --card: #fff; --accent: #2e7d32; }
@media (prefers-color-scheme: dark) { :root { --bg: #121512; --fg: #e8efe8; --muted: #9fb0a2; --card: #1c211d; --accent: #81c784; } }
* { box-sizing: border-box; }
body { margin: 0; min-height: 100vh; display: grid; place-items: center; padding: 16px;
  background: var(--bg); color: var(--fg); font: 17px/1.55 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif; }
.card { max-width: 560px; width: 100%; background: var(--card); border-radius: 20px; padding: 28px; box-shadow: 0 8px 30px rgb(0 0 0 / 0.08); }
h1 { margin: 0 0 12px; color: var(--accent); font-size: 1.8rem; }
.muted { color: var(--muted); font-size: 0.92rem; }
.code { font: 600 2.2rem/1.2 ui-monospace, "Cascadia Mono", monospace; letter-spacing: 0.12em; text-align: center; margin: 20px 0; }