:root {
  --bg: #f5f7fa; --card: #ffffff; --text: #1d2430; --muted: #5b6573;
  --accent: #1f6feb; --accent-text: #ffffff; --border: #dde2ea; --code: #eef1f5;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0f141b; --card: #171e28; --text: #e6eaf0; --muted: #9aa5b4;
    --accent: #4c8dff; --accent-text: #0f141b; --border: #283241; --code: #202a37;
  }
}
* { box-sizing: border-box; }
body {
  margin: 0; background: var(--bg); color: var(--text);
  font: 16px/1.55 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}
.wrap { max-width: 640px; margin: 0 auto; padding: 48px 16px; }
h1 { font-size: 1.9rem; margin: 0 0 8px; }
h2 { font-size: 1.1rem; margin: 0 0 12px; }
.lead { color: var(--muted); margin: 0 0 32px; }
.card {
  background: var(--card); border: 1px solid var(--border);
  border-radius: 10px; padding: 24px; margin-bottom: 20px;
}
.btn {
  display: inline-block; padding: 12px 20px; border-radius: 8px;
  background: var(--accent); color: var(--accent-text);
  font-weight: 600; text-decoration: none;
}
.btn.disabled { opacity: .45; pointer-events: none; cursor: not-allowed; }
.muted { color: var(--muted); font-size: .9rem; }
code { background: var(--code); padding: 2px 6px; border-radius: 4px; font-size: .9em; }
.key { word-break: break-all; }
dl { display: grid; grid-template-columns: max-content 1fr; gap: 8px 16px; margin: 0; }
dt { font-weight: 600; }
dd { margin: 0; min-width: 0; }
@media (max-width: 420px) { dl { grid-template-columns: 1fr; } dt { margin-top: 8px; } }
footer { margin-top: 28px; }