:root {
  color-scheme: light;
  --ink: #122033;
  --muted: #5c6b7d;
  --blue: #1473e6;
  --green: #2f865c;
  --line: #dce7f2;
  --paper: #ffffff;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  color: var(--ink);
  background: #f5f9fd;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Hiragino Sans", "Noto Sans JP", sans-serif;
  font-size: 17px;
  line-height: 1.8;
}

.wrap {
  width: min(860px, calc(100% - 40px));
  margin: 0 auto;
}

.hero {
  padding: 72px 0 58px;
  background:
    radial-gradient(circle at 80% 10%, rgba(47, 134, 92, .18), transparent 34%),
    linear-gradient(145deg, #e6f3ff, #f5fbf8);
  border-bottom: 1px solid var(--line);
}

.eyebrow {
  color: var(--blue);
  font-size: 14px;
  font-weight: 700;
  letter-spacing: .08em;
  text-transform: uppercase;
}

h1, h2 { line-height: 1.35; }
h1 { margin: 12px 0 14px; font-size: clamp(34px, 7vw, 52px); }
h2 { margin: 0 0 12px; font-size: 23px; }
.lead { max-width: 700px; margin: 0; color: var(--muted); font-size: 19px; }

nav { display: flex; gap: 10px; margin-top: 28px; }
.pill {
  display: inline-flex;
  padding: 6px 16px;
  color: var(--blue);
  background: rgba(255,255,255,.8);
  border: 1px solid rgba(20,115,230,.2);
  border-radius: 999px;
  text-decoration: none;
}
.pill.active { color: #fff; background: var(--blue); }

main { padding: 54px 0 72px; }
article { scroll-margin-top: 20px; }
article > h1 { margin-top: 0; font-size: 36px; }
section {
  margin: 22px 0;
  padding: 26px 28px;
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: 18px;
  box-shadow: 0 8px 30px rgba(35, 73, 111, .05);
}
p { margin: 0 0 14px; }
p:last-child { margin-bottom: 0; }
li + li { margin-top: 8px; }
a { color: var(--blue); text-underline-offset: 3px; }
.updated { color: var(--muted); font-size: 14px; }
.links { padding-left: 22px; }
hr { margin: 72px 0; border: 0; border-top: 1px solid var(--line); }

footer {
  padding: 28px 0;
  color: var(--muted);
  background: #eaf2f8;
  border-top: 1px solid var(--line);
  font-size: 14px;
}

@media (max-width: 600px) {
  body { font-size: 16px; }
  .hero { padding: 48px 0 40px; }
  main { padding-top: 36px; }
  section { padding: 21px 20px; border-radius: 15px; }
  ul { padding-left: 22px; }
}