:root {
  --ink: #1f2933;
  --muted: #7b8794;
  --bg: #ffffff;
  --rule: #e4e7eb;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Hiragino Sans", "Noto Sans JP", sans-serif;
  font-weight: 300;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

main {
  max-width: 640px;
  margin: 0 auto;
  padding: 64px 24px 96px;
}

.hero {
  text-align: center;
  padding: 32px 0 64px;
}

.hero .logo {
  width: 96px;
  height: 96px;
  margin: 0 auto 24px;
  border-radius: 50%;
  border: 5px solid var(--ink);
  box-sizing: border-box;
}

.hero h1 {
  font-size: 2.4rem;
  font-weight: 300;
  letter-spacing: 2px;
  margin: 0 0 8px;
}

.tagline {
  font-size: 1.05rem;
  margin: 4px 0;
  color: var(--ink);
}

.tagline-ja {
  color: var(--muted);
  font-size: 0.95rem;
}

section {
  border-top: 1px solid var(--rule);
  padding: 40px 0;
}

h2 {
  font-size: 1.1rem;
  font-weight: 400;
  letter-spacing: 1px;
  margin: 0 0 16px;
  text-transform: uppercase;
  color: var(--muted);
}

p {
  margin: 0 0 16px;
  font-size: 1.05rem;
}

ol {
  padding-left: 1.2em;
}

ol li {
  margin-bottom: 12px;
}

strong { font-weight: 500; }

a {
  color: var(--ink);
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
}

a:hover { color: var(--muted); }

footer {
  border-top: 1px solid var(--rule);
  padding-top: 32px;
  margin-top: 32px;
  text-align: center;
  color: var(--muted);
  font-size: 0.9rem;
}

footer p { margin: 4px 0; }