:root {
  --bg: #ffffff;
  --text: #1d1d1f;
  --muted: #6e6e73;
  --line: #d2d2d7;
  --link: #0066cc;
  --panel: #f5f5f7;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #000000;
    --text: #f5f5f7;
    --muted: #a1a1a6;
    --line: #424245;
    --link: #2997ff;
    --panel: #1c1c1e;
  }
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Hiragino Sans", "Hiragino Kaku Gothic ProN", "Noto Sans JP", sans-serif;
  line-height: 1.8;
  font-size: 16px;
}

header, main, footer {
  max-width: 720px;
  margin: 0 auto;
  padding: 0 16px;
}

header { padding-top: 20px; font-size: 14px; }
footer { padding-top: 32px; padding-bottom: 40px; font-size: 14px; color: var(--muted); border-top: 1px solid var(--line); margin-top: 48px; }

a { color: var(--link); }
header a { color: var(--muted); text-decoration: none; }

h1 { font-size: 28px; line-height: 1.4; margin: 24px 0 8px; }
h2 { font-size: 20px; margin: 36px 0 8px; }
.lead { font-size: 17px; }
.note { color: var(--muted); font-size: 14px; }

dt { font-weight: 600; margin-top: 20px; }
dd { margin: 4px 0 0; }

.apps { padding-left: 20px; }
.apps li { margin: 8px 0; }

.table { overflow-x: auto; }
table { border-collapse: collapse; width: 100%; font-size: 14px; }
th, td { text-align: left; vertical-align: top; padding: 8px; border-bottom: 1px solid var(--line); }
thead th { background: var(--panel); }