:root {
  --color-bg: #ffffff;
  --color-text: #1a1a1a;
  --color-muted: #6b7280;
  --color-border: #e5e7eb;
  --color-accent: #0f766e;
  --color-accent-hover: #0d5f59;
  --color-surface: #f9fafb;
  --max-width: 1080px;
  --font-jp: "Noto Sans JP", -apple-system, BlinkMacSystemFont, "Hiragino Kaku Gothic ProN", "Yu Gothic Medium", sans-serif;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-jp);
  color: var(--color-text);
  background: var(--color-bg);
  line-height: 1.7;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
}

a {
  color: var(--color-accent);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

/* ─────────── Header ─────────── */
header.site-header {
  border-bottom: 1px solid var(--color-border);
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(8px);
  position: sticky;
  top: 0;
  z-index: 10;
}

.header-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 64px;
}

.header-logo img {
  height: 28px;
  width: auto;
  display: block;
}

.header-cta {
  display: inline-flex;
  align-items: center;
  padding: 8px 18px;
  background: var(--color-accent);
  color: #fff;
  border-radius: 6px;
  font-weight: 600;
  font-size: 14px;
  transition: background 0.15s;
}

.header-cta:hover {
  background: var(--color-accent-hover);
  text-decoration: none;
  color: #fff;
}

/* ─────────── Hero ─────────── */
.hero {
  padding: 96px 0 72px;
  text-align: center;
}

.hero h1 {
  font-size: 48px;
  font-weight: 700;
  line-height: 1.3;
  letter-spacing: -0.01em;
  margin-bottom: 24px;
}

.hero .lead {
  font-size: 18px;
  color: var(--color-muted);
  margin-bottom: 40px;
  max-width: 640px;
  margin-left: auto;
  margin-right: auto;
}

.hero .cta-row {
  display: flex;
  gap: 12px;
  justify-content: center;
  flex-wrap: wrap;
}

.btn-primary {
  display: inline-flex;
  align-items: center;
  padding: 14px 32px;
  background: var(--color-accent);
  color: #fff;
  border-radius: 8px;
  font-weight: 600;
  font-size: 16px;
  transition: background 0.15s;
}

.btn-primary:hover {
  background: var(--color-accent-hover);
  text-decoration: none;
  color: #fff;
}

.btn-secondary {
  display: inline-flex;
  align-items: center;
  padding: 14px 32px;
  background: transparent;
  color: var(--color-text);
  border: 1px solid var(--color-border);
  border-radius: 8px;
  font-weight: 600;
  font-size: 16px;
  transition: border-color 0.15s;
}

.btn-secondary:hover {
  border-color: var(--color-text);
  text-decoration: none;
  color: var(--color-text);
}

/* ─────────── Features ─────────── */
.features {
  padding: 80px 0;
  background: var(--color-surface);
}

.section-title {
  font-size: 32px;
  font-weight: 700;
  text-align: center;
  margin-bottom: 16px;
}

.section-lead {
  text-align: center;
  color: var(--color-muted);
  margin-bottom: 56px;
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 32px;
}

.feature-card {
  padding: 32px;
  background: #fff;
  border: 1px solid var(--color-border);
  border-radius: 12px;
}

.feature-card h3 {
  font-size: 18px;
  font-weight: 700;
  margin-bottom: 12px;
}

.feature-card p {
  color: var(--color-muted);
  font-size: 14px;
  line-height: 1.7;
}

/* ─────────── About ─────────── */
.about {
  padding: 80px 0;
}

.about-grid {
  display: grid;
  grid-template-columns: 200px 1fr;
  gap: 24px 48px;
  font-size: 15px;
  max-width: 720px;
  margin: 0 auto;
}

.about-grid dt {
  font-weight: 600;
  color: var(--color-muted);
}

.about-grid dd {
  color: var(--color-text);
}

/* ─────────── Footer ─────────── */
footer.site-footer {
  border-top: 1px solid var(--color-border);
  padding: 48px 0;
  font-size: 14px;
  color: var(--color-muted);
}

.footer-inner {
  display: flex;
  flex-wrap: wrap;
  gap: 32px;
  justify-content: space-between;
  align-items: flex-start;
}

.footer-brand {
  font-weight: 600;
  color: var(--color-text);
  margin-bottom: 8px;
}

.footer-links {
  display: flex;
  gap: 24px;
  flex-wrap: wrap;
}

.footer-links a {
  color: var(--color-muted);
}

.footer-copy {
  width: 100%;
  text-align: left;
  font-size: 12px;
  margin-top: 24px;
  padding-top: 24px;
  border-top: 1px solid var(--color-border);
  color: var(--color-muted);
}

/* ─────────── Legal pages ─────────── */
.legal {
  padding: 64px 0 96px;
  max-width: 800px;
  margin: 0 auto;
}

.legal h1 {
  font-size: 32px;
  font-weight: 700;
  margin-bottom: 8px;
}

.legal .updated {
  color: var(--color-muted);
  font-size: 14px;
  margin-bottom: 40px;
}

.legal h2 {
  font-size: 20px;
  font-weight: 700;
  margin: 40px 0 16px;
}

.legal h3 {
  font-size: 16px;
  font-weight: 700;
  margin: 24px 0 8px;
}

.legal p,
.legal li {
  font-size: 15px;
  line-height: 1.9;
  margin-bottom: 12px;
}

.legal ul,
.legal ol {
  margin-bottom: 16px;
  padding-left: 24px;
}

.legal table {
  width: 100%;
  border-collapse: collapse;
  margin: 16px 0 24px;
}

.legal table th,
.legal table td {
  border-bottom: 1px solid var(--color-border);
  padding: 14px 12px;
  text-align: left;
  vertical-align: top;
  font-size: 14px;
  line-height: 1.7;
}

.legal table th {
  width: 36%;
  font-weight: 600;
  background: var(--color-surface);
}

.back-link {
  display: inline-block;
  margin-bottom: 24px;
  font-size: 14px;
}

/* ─────────── Responsive ─────────── */
@media (max-width: 720px) {
  .hero {
    padding: 64px 0 48px;
  }
  .hero h1 {
    font-size: 32px;
  }
  .hero .lead {
    font-size: 16px;
  }
  .feature-grid {
    grid-template-columns: 1fr;
  }
  .about-grid {
    grid-template-columns: 1fr;
    gap: 4px 0;
  }
  .about-grid dt {
    margin-top: 12px;
  }
  .legal table th {
    width: 40%;
    font-size: 13px;
  }
  .legal table td {
    font-size: 13px;
  }
}