/* ═══════════════════════════════════════════
   base.css
   共通 design tokens / reset / レイアウト / header / footer
   全ページで読み込む
   ═══════════════════════════════════════════ */


/* ── Design Tokens ────────────────────────── */

:root {
  /* Colors */
  --bg:           #ffffff;
  --bg-section:   #f5f6f8;
  --bg-alt:       #fafbfc;
  --ink:          #0d1f3c;
  --ink-soft:     #9aa3b0;
  --ink-muted:    #c4cad3;
  --navy:         #0d1f3c;
  --navy-soft:    #1e3557;
  --border:       #e8eaed;

  /* Typography */
  --font-display: 'DM Serif Display', Georgia, serif;
  --font-body:    'Noto Sans JP', 'Hiragino Sans', sans-serif;

  /* Layout */
  --nav-h:  60px;
  --max-w:  760px;
}


/* ── Reset ────────────────────────────────── */

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

html {
  scroll-behavior: smooth;
}


/* ── Body ─────────────────────────────────── */

body {
  font-family: var(--font-body);
  background: var(--bg);
  color: var(--ink);
  -webkit-font-smoothing: antialiased;
  line-height: 1.8;
}


/* ── Links ────────────────────────────────── */

a {
  color: inherit;
  text-decoration: none;
}


/* ── Images ───────────────────────────────── */

img {
  display: block;
  max-width: 100%;
  height: auto;
}


/* ── Inner (共通コンテナ) ─────────────────── */

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


/* ── Header ───────────────────────────────── */

header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  height: var(--nav-h);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 32px;
  background: rgba(255, 255, 255, 0.88);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid rgba(13, 31, 60, 0.04);
  transition: box-shadow 0.3s;
}

.nav-brand {
  display: flex;
  align-items: center;
}

.nav-brand img {
  display: block;
  height: 30px;
  width: auto;
  mix-blend-mode: multiply;
}

.nav-links {
  display: flex;
  gap: 32px;
  list-style: none;
}

.nav-links a {
  font-size: 0.78rem;
  letter-spacing: 0.08em;
  color: #7a8594;
  font-weight: 400;
  transition: color 0.2s;
}

.nav-links a:hover {
  color: var(--ink);
}

.nav-links a[aria-current="page"] {
  color: var(--ink);
  border-bottom: 1px solid rgba(13, 31, 60, 0.2);
  padding-bottom: 2px;
}

.nav--inactive {
  opacity: 0.4;
  pointer-events: none;
  cursor: default;
}


/* ── Label (小見出し) ─────────────────────── */

.label {
  display: block;
  font-size: 0.65rem;
  letter-spacing: 0.2em;
  color: var(--ink-muted);
  font-weight: 400;
  text-transform: uppercase;
  margin-bottom: 16px;
}


/* ── Section Title (セクション大見出し) ────── */

.section-title {
  font-family: var(--font-display);
  font-size: clamp(1.6rem, 4vw, 2.4rem);
  color: var(--ink);
  letter-spacing: 0.02em;
  line-height: 1.25;
  margin-bottom: 32px;
}


/* ── Button ───────────────────────────────── */

.btn {
  display: inline-block;
  font-size: 0.75rem;
  letter-spacing: 0.12em;
  color: var(--navy);
  border: 1px solid rgba(13, 31, 60, 0.35);
  padding: 10px 28px;
  border-radius: 2px;
  font-weight: 400;
  transition: background 0.25s ease, color 0.25s ease, border-color 0.25s ease;
  cursor: pointer;
}

.btn:hover {
  background: var(--navy);
  color: #fff;
  border-color: var(--navy);
}

.btn--coming-soon {
  font-size: 0.68rem;
  letter-spacing: 0.2em;
  color: var(--ink-muted);
  border-color: var(--border);
  cursor: default;
  pointer-events: none;
}


/* ── Section ──────────────────────────────── */

.section {
  padding: 88px 0 96px;
  background: var(--bg);
  border-top: 1px solid var(--border);
  text-align: center;
}

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


/* ── Hero ─────────────────────────────────── */

.hero {
  min-height: 80vh;
  padding-top: var(--nav-h);
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  background: var(--bg-section);
}

.hero__inner {
  padding: 80px 24px 60px;
  max-width: var(--max-w);
  margin: 0 auto;
}

.hero__eyebrow {
  font-size: 0.7rem;
  letter-spacing: 0.2em;
  color: var(--ink-muted);
  text-transform: uppercase;
  margin-bottom: 24px;
}

.hero__title {
  font-family: var(--font-display);
  font-size: clamp(2rem, 6vw, 3.4rem);
  color: var(--ink);
  line-height: 1.2;
  letter-spacing: 0.02em;
  margin-bottom: 28px;
}

.hero__lead {
  font-size: clamp(1rem, 2.2vw, 1.2rem);
  color: var(--ink-soft);
  font-weight: 300;
  letter-spacing: 0.04em;
  line-height: 1.9;
  margin-bottom: 16px;
}

.hero__note {
  font-size: clamp(0.8rem, 1.6vw, 0.9rem);
  color: var(--ink-muted);
  font-weight: 300;
  letter-spacing: 0.04em;
  line-height: 1.9;
  opacity: 0.85;
}


/* ── Footer ───────────────────────────────── */

.footer {
  padding: 28px 40px;
  background: var(--bg);
  border-top: 1px solid var(--border);
  text-align: center;
}

.footer__copy {
  font-size: 0.68rem;
  letter-spacing: 0.1em;
  color: var(--ink-muted);
  font-weight: 300;
}


/* ── Utility ──────────────────────────────── */

.divider {
  display: none;
}


/* ── Responsive ───────────────────────────── */

@media (max-width: 640px) {
  header {
    padding: 0 20px;
  }

  .nav-links {
    gap: 20px;
  }

  .hero__inner {
    padding: 60px 24px 48px;
  }

  .section {
    padding: 64px 0 72px;
  }
}