:root {
  --bg: #f7f7f5;
  --card: #ffffff;
  --text: #1c1c1a;
  --muted: #55554f;
  --line: #dcdcd6;
  --accent: #0b5cad;
  --accent-bg: #e8f1fb;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #161615;
    --card: #20201e;
    --text: #ececea;
    --muted: #b4b4ad;
    --line: #3a3a37;
    --accent: #7db4ee;
    --accent-bg: #1c2a3a;
  }
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 17px/1.6 system-ui, -apple-system, "Segoe UI", Roboto, "Hiragino Sans", "Noto Sans JP", sans-serif;
}
.skip-link { position: absolute; left: -9999px; }
.skip-link:focus { left: 16px; top: 16px; background: var(--card); padding: 8px 12px; border: 2px solid var(--accent); z-index: 1; }
header.site, main, footer.site { max-width: 880px; margin: 0 auto; padding: 0 16px; }
header.site { padding-top: 48px; padding-bottom: 24px; }
.brand { margin: 0 0 8px; font-weight: 600; letter-spacing: .04em; color: var(--accent); }
h1 { margin: 0 0 12px; font-size: clamp(28px, 5vw, 40px); line-height: 1.2; }
.lead { margin: 0; color: var(--muted); max-width: 40em; }
.tools { list-style: none; margin: 8px 0 40px; padding: 0; display: grid; gap: 16px; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); }
.card {
  display: flex; flex-direction: column; gap: 8px; height: 100%;
  padding: 20px; background: var(--card); color: inherit; text-decoration: none;
  border: 1px solid var(--line); border-radius: 12px;
}
.card:hover, .card:focus-visible { border-color: var(--accent); outline: none; box-shadow: 0 0 0 3px var(--accent-bg); }
.flag { align-self: flex-start; font-size: 13px; font-weight: 600; padding: 2px 8px; border-radius: 6px; background: var(--accent-bg); color: var(--accent); }
.name { font-size: 19px; font-weight: 600; line-height: 1.3; }
.what { color: var(--muted); flex: 1; }
.go { color: var(--accent); font-weight: 600; }
.go::after { content: " \2192"; }
.how { border-top: 1px solid var(--line); padding-top: 24px; margin-bottom: 40px; }
.how h2 { font-size: 20px; margin: 0 0 8px; }
.how ul { margin: 0; padding-left: 20px; color: var(--muted); }
footer.site { border-top: 1px solid var(--line); padding-top: 16px; padding-bottom: 40px; color: var(--muted); font-size: 15px; }
.brand a { color: inherit; text-decoration: none; }
.doc { max-width: 720px; padding-bottom: 40px; }
.doc h2 { font-size: 20px; margin: 28px 0 8px; }
.doc ul { padding-left: 20px; }
a { color: var(--accent); }