:root {
  --bg: #f4f5f7;
  --card: #ffffff;
  --text: #0b0f14;
  --muted: #5d6676;
  --line: #e4e7ec;
  --accent: #2563eb;
  --warn-bg: #fff7e6;
  --warn-line: #f5c26b;
  color-scheme: light;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0e1115;
    --card: #161a20;
    --text: #e6e8eb;
    --muted: #8b95a5;
    --line: #2e3540;
    --accent: #4f8cff;
    --warn-bg: #2a2214;
    --warn-line: #8a6a2a;
    color-scheme: dark;
  }
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.6 Inter, "Segoe UI", system-ui, -apple-system, sans-serif;
}

main {
  max-width: 760px;
  margin: 0 auto;
  padding: 40px 16px 64px;
}

header p { color: var(--muted); margin-top: 4px; }

h1 { margin: 0; font-size: 30px; line-height: 1.2; }
h2 { margin: 36px 0 10px; font-size: 20px; }

.card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 20px;
  margin-top: 20px;
}

.button {
  display: inline-block;
  padding: 12px 20px;
  border-radius: 10px;
  background: var(--accent);
  color: #fff;
  font-weight: 700;
  text-decoration: none;
}

.note {
  background: var(--warn-bg);
  border: 1px solid var(--warn-line);
  border-radius: 10px;
  padding: 12px 14px;
}

ol li, ul li { margin: 6px 0; }

code {
  font-family: Consolas, ui-monospace, monospace;
  font-size: 0.92em;
}

a { color: var(--accent); }

footer { margin-top: 48px; color: var(--muted); font-size: 14px; }