:root {
  --bg: #fafaf7;
  --text: #1c1c1c;
  --muted: #6b6b6b;
  --accent: #1f6feb;
  --line: #e4e4de;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #141414;
    --text: #ededed;
    --muted: #a0a0a0;
    --accent: #5b9dff;
    --line: #2a2a2a;
  }
}
* { box-sizing: border-box; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 17px/1.6 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}
main {
  max-width: 640px;
  margin: 0 auto;
  padding: 56px 20px 32px;
  min-height: calc(100vh - 80px);
}
h1 { font-size: 2rem; line-height: 1.2; margin: 0 0 16px; }
h2 { font-size: 1.1rem; margin: 32px 0 6px; }
p { margin: 0 0 12px; }
a { color: var(--accent); }
.lead { font-size: 1.15rem; color: var(--muted); margin-bottom: 28px; }
.button {
  display: inline-block;
  background: var(--accent);
  color: #fff;
  text-decoration: none;
  padding: 14px 24px;
  border-radius: 10px;
  font-weight: 600;
}
.back { display: inline-block; margin-bottom: 24px; text-decoration: none; }
footer {
  border-top: 1px solid var(--line);
  padding: 20px;
  text-align: center;
  font-size: 0.9rem;
  color: var(--muted);
}
footer a { color: var(--muted); margin: 0 10px; }