:root {
  --bg: #f6f8fb;
  --bg-alt: #eef2f7;
  --text: #0f172a;
  --muted: #475569;
  --primary: #0ea5a4;
  --primary-dark: #0b7f7e;
  --line: #d9e1ec;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: "Hiragino Sans", "Noto Sans JP", sans-serif;
  color: var(--text);
  background: linear-gradient(160deg, #ffffff 0%, var(--bg) 55%, #ecf4f9 100%);
  line-height: 1.65;
}

.container {
  width: min(1040px, 92vw);
  margin: 0 auto;
}

.site-header {
  position: sticky;
  top: 0;
  backdrop-filter: blur(6px);
  background: color-mix(in srgb, #ffffff 78%, transparent);
  border-bottom: 1px solid var(--line);
  z-index: 10;
}

.header-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  min-height: 68px;
}

.brand {
  font-weight: 800;
  letter-spacing: 0.08em;
  text-decoration: none;
  color: var(--text);
}

.nav {
  display: flex;
  gap: 1rem;
}

.nav a {
  color: var(--muted);
  text-decoration: none;
  font-weight: 600;
}

.hero {
  padding: 96px 0 72px;
}

.eyebrow {
  color: var(--primary-dark);
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

h1 {
  margin: 0.25rem 0 1rem;
  font-size: clamp(2rem, 5vw, 3.4rem);
  line-height: 1.2;
}

.lead {
  max-width: 58ch;
  color: var(--muted);
}

.hero-actions {
  display: flex;
  gap: 0.75rem;
  margin-top: 1.5rem;
}

.btn {
  display: inline-block;
  padding: 0.72rem 1.1rem;
  border-radius: 10px;
  font-weight: 700;
  text-decoration: none;
}

.btn-primary {
  background: var(--primary);
  color: #fff;
}

.btn-primary:hover {
  background: var(--primary-dark);
}

.btn-ghost {
  border: 1px solid var(--line);
  color: var(--text);
  background: #fff;
}

.section {
  padding: 52px 0;
}

.section-alt {
  background: var(--bg-alt);
}

h2 {
  margin: 0 0 0.8rem;
  font-size: clamp(1.4rem, 2.5vw, 2rem);
}

.cards {
  margin-top: 1rem;
  display: grid;
  gap: 1rem;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
}

.card {
  border: 1px solid var(--line);
  border-radius: 14px;
  background: #fff;
  padding: 1rem;
}

.card h3 {
  margin-top: 0;
}

.news-list {
  padding-left: 1.2rem;
}

.site-footer {
  border-top: 1px solid var(--line);
  padding: 24px 0;
}

.footer-inner {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  flex-wrap: wrap;
  color: var(--muted);
}

@media (max-width: 720px) {
  .nav {
    display: none;
  }

  .hero {
    padding-top: 72px;
  }
}