:root {
  --bg: #ffffff;
  --text: #1f2430;
  --muted: #5b6275;
  --accent: #2b59c3;
  --border: #dde1ea;
  --note-bg: #f3f6fd;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #14171f;
    --text: #e6e9f2;
    --muted: #9aa3b8;
    --accent: #8fb0ff;
    --border: #2b3040;
    --note-bg: #1b2030;
  }
}

* { box-sizing: border-box; }

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

main {
  max-width: 760px;
  margin: 0 auto;
  padding: 24px 16px 64px;
}

header.site {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 12px;
  flex-wrap: wrap;
  border-bottom: 1px solid var(--border);
  padding-bottom: 12px;
  margin-bottom: 24px;
}

header.site a.brand {
  font-weight: 700;
  font-size: 1.1rem;
  color: var(--text);
  text-decoration: none;
}

nav a { margin-left: 14px; }
a { color: var(--accent); }

h1 { font-size: 1.8rem; line-height: 1.25; margin: 0 0 4px; }
h2 { font-size: 1.25rem; margin: 32px 0 8px; }
h3 { font-size: 1.05rem; margin: 20px 0 4px; }

p, ul { margin: 8px 0; }
ul { padding-left: 22px; }
li { margin: 4px 0; }

.meta { color: var(--muted); font-size: 0.9rem; }

.note {
  background: var(--note-bg);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 12px 14px;
  margin: 16px 0;
}

footer { color: var(--muted); font-size: 0.85rem; margin-top: 40px; border-top: 1px solid var(--border); padding-top: 12px; }