:root {
  --bg: #121211;
  --paper: #1c1c1a;
  --ink: #f7f5ef;
  --sub: #d2d0c8;
  --muted: #a9a79f;
  --line: #3a3934;
  --accent: #d4ff3a;
  --accent-ink: #0f0f0e;
}
@media (prefers-color-scheme: light) {
  :root {
    --bg: #e9e7e1;
    --paper: #f7f6f2;
    --ink: #161614;
    --sub: #45443f;
    --muted: #6b6962;
    --line: #cfcbc2;
    --accent: #6f8f00;
    --accent-ink: #ffffff;
  }
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: "Hiragino Sans", "Hiragino Kaku Gothic ProN", "Yu Gothic", "Noto Sans JP", system-ui, sans-serif;
  line-height: 1.8;
  font-size: 15px;
}
main { max-width: 720px; margin: 0 auto; padding: 40px 16px 64px; }
header.brand { display: flex; align-items: center; gap: 14px; margin-bottom: 28px; }
header.brand img { width: 56px; height: 56px; border-radius: 13px; }
header.brand .name { font-weight: 700; font-size: 20px; }
header.brand .tag { color: var(--muted); font-size: 13px; }
h1 { font-size: 26px; line-height: 1.4; margin: 0 0 8px; }
h2 { font-size: 18px; margin: 36px 0 8px; padding-top: 4px; }
h3 { font-size: 15px; margin: 20px 0 4px; }
p, li { color: var(--sub); }
ul { padding-left: 1.3em; }
a { color: var(--accent); }
.meta { color: var(--muted); font-size: 13px; }
.card { background: var(--paper); border: 1px solid var(--line); border-radius: 18px; padding: 18px 18px 6px; margin: 16px 0; }
.card h3:first-child { margin-top: 0; }
.button {
  display: inline-block; background: var(--accent); color: var(--accent-ink); text-decoration: none;
  font-weight: 700; padding: 12px 20px; border-radius: 999px; margin: 8px 0 16px;
}
nav.links { display: flex; flex-wrap: wrap; gap: 8px 18px; margin-top: 40px; padding-top: 16px; border-top: 1px solid var(--line); font-size: 13px; }
nav.links a { color: var(--muted); }