:root {
  color-scheme: light dark;
  --accent: #dc8b16;
  --accent-soft: color-mix(in srgb, var(--accent) 12%, transparent);
  --background: #f6f6f8;
  --surface: #ffffff;
  --text: #19191c;
  --secondary: #66666e;
  --border: #e6e6e9;
}

@media (prefers-color-scheme: dark) {
  :root {
    --accent: #f0a638;
    --accent-soft: color-mix(in srgb, var(--accent) 14%, transparent);
    --background: #111114;
    --surface: #1c1c20;
    --text: #f3f3f5;
    --secondary: #aaaab2;
    --border: #303036;
  }
}

* {
  box-sizing: border-box;
}

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

main {
  width: min(100% - 32px, 760px);
  margin: 0 auto;
  padding: 64px 0 72px;
}

header {
  margin-bottom: 28px;
}

.eyebrow {
  margin: 0 0 8px;
  color: var(--accent);
  font-size: 0.82rem;
  font-weight: 700;
  letter-spacing: 0.08em;
}

h1 {
  margin: 0;
  font-size: clamp(2rem, 7vw, 3rem);
  line-height: 1.25;
  letter-spacing: -0.03em;
}

.lead {
  margin: 14px 0 0;
  color: var(--secondary);
  font-size: 1.05rem;
}

article {
  padding: clamp(24px, 6vw, 48px);
  border: 1px solid var(--border);
  border-radius: 24px;
  background: var(--surface);
  box-shadow: 0 16px 44px rgb(0 0 0 / 0.05);
}

section + section {
  margin-top: 36px;
  padding-top: 34px;
  border-top: 1px solid var(--border);
}

h2 {
  margin: 0 0 10px;
  font-size: 1.2rem;
  line-height: 1.5;
}

p {
  margin: 0;
}

p + p,
ul + p {
  margin-top: 12px;
}

ul {
  margin: 10px 0 0;
  padding-left: 1.35em;
}

li + li {
  margin-top: 5px;
}

a {
  color: var(--accent);
  font-weight: 600;
  text-underline-offset: 3px;
}

.summary {
  margin-bottom: 36px;
  padding: 18px 20px;
  border-radius: 16px;
  background: var(--accent-soft);
  font-weight: 600;
}

.date {
  margin-top: 32px;
  color: var(--secondary);
  font-size: 0.88rem;
}

footer {
  padding-top: 24px;
  color: var(--secondary);
  font-size: 0.85rem;
  text-align: center;
}

@media (max-width: 520px) {
  main {
    padding-top: 38px;
  }

  article {
    border-radius: 20px;
  }
}

nav {
  display: flex;
  gap: 18px;
  margin-top: 18px;
  font-size: 0.95rem;
}

nav a[aria-current="page"] {
  color: var(--text);
  text-decoration: none;
}

h3 {
  margin: 20px 0 4px;
  font-size: 1rem;
  line-height: 1.6;
}

h2 + h3 {
  margin-top: 12px;
}

.contact {
  display: inline-block;
  margin-top: 14px;
  padding: 10px 18px;
  border-radius: 999px;
  background: var(--accent-soft);
  text-decoration: none;
}