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

:root {
  --sky: #0ea5e9;
  --sky-dark: #0369a1;
  --sky-light: #e0f2fe;
  --amber: #f59e0b;
  --amber-dark: #d97706;
  --light: #f8fafc;
  --white: #ffffff;
  --gray: #64748b;
  --text: #1e293b;
  --border: #e2e8f0;
}

body {
  font-family: 'Noto Sans JP', sans-serif;
  color: var(--text);
  background: var(--white);
  line-height: 1.7;
}

/* ========== ナビ ========== */
header {
  position: fixed; top: 0; left: 0; right: 0;
  background: rgba(255,255,255,0.97);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
  z-index: 100; height: 64px;
  display: flex; align-items: center;
  justify-content: space-between; padding: 0 48px;
}
.logo { color: var(--sky-dark); font-size: 1rem; font-weight: 700; text-decoration: none; letter-spacing: 0.04em; display: flex; align-items: center; gap: 10px; }
.logo-mark {
  width: 32px; height: 32px; background: var(--sky);
  border-radius: 8px; display: flex; align-items: center; justify-content: center;
  color: white; font-weight: 900; font-size: 0.9rem;
}
nav { display: flex; align-items: center; gap: 4px; }
nav a {
  color: var(--gray); text-decoration: none; font-size: 0.85rem;
  padding: 8px 16px; border-radius: 6px; font-weight: 500;
  transition: color 0.2s, background 0.2s;
}
nav a:hover, nav a.active { color: var(--sky-dark); background: var(--sky-light); }
.nav-cta {
  background: var(--sky) !important; color: white !important;
  font-weight: 700 !important; margin-left: 8px;
}
.nav-cta:hover { background: var(--sky-dark) !important; }

/* ========== ボタン ========== */
.btn-primary {
  display: inline-block; background: var(--sky); color: white;
  padding: 13px 36px; border-radius: 8px; font-weight: 700;
  font-size: 0.95rem; text-decoration: none;
  transition: background 0.2s, transform 0.2s, box-shadow 0.2s;
  box-shadow: 0 4px 14px rgba(14,165,233,0.35);
}
.btn-primary:hover { background: var(--sky-dark); transform: translateY(-2px); box-shadow: 0 8px 20px rgba(14,165,233,0.4); }
.btn-outline {
  display: inline-block; border: 2px solid var(--sky);
  color: var(--sky); padding: 11px 32px; border-radius: 8px;
  font-weight: 700; font-size: 0.95rem; text-decoration: none;
  transition: background 0.2s, color 0.2s;
}
.btn-outline:hover { background: var(--sky); color: white; }
.btn-amber {
  display: inline-block; background: var(--amber); color: white;
  padding: 13px 36px; border-radius: 8px; font-weight: 700;
  font-size: 0.95rem; text-decoration: none;
  box-shadow: 0 4px 14px rgba(245,158,11,0.35);
  transition: background 0.2s, transform 0.2s;
}
.btn-amber:hover { background: var(--amber-dark); transform: translateY(-2px); }

/* ========== セクション共通 ========== */
.section { padding: 96px 80px; }
.section-light { background: var(--light); }
.section-sky { background: var(--sky-light); }
.section-tag {
  font-size: 0.72rem; font-weight: 700; letter-spacing: 0.25em;
  text-transform: uppercase; color: var(--sky); margin-bottom: 12px;
}
.section h2 {
  font-size: clamp(1.6rem, 2.4vw, 2.4rem); font-weight: 900;
  line-height: 1.3; color: var(--text); margin-bottom: 48px;
}
.lead { font-size: 1rem; color: var(--gray); max-width: 560px; margin-bottom: 48px; margin-top: -32px; }

/* ========== フッター ========== */
footer {
  background: var(--text); color: rgba(255,255,255,0.45);
  padding: 56px 80px 32px;
}
.footer-inner {
  display: flex; justify-content: space-between;
  gap: 40px; padding-bottom: 40px;
  border-bottom: 1px solid rgba(255,255,255,0.08);
  margin-bottom: 24px; flex-wrap: wrap;
}
.footer-logo { display: flex; align-items: center; gap: 10px; margin-bottom: 12px; }
.footer-logo-mark { width: 32px; height: 32px; background: var(--sky); border-radius: 8px; display: flex; align-items: center; justify-content: center; color: white; font-weight: 900; }
.footer-logo span { color: var(--white); font-size: 1rem; font-weight: 700; }
.footer-info { font-size: 0.8rem; line-height: 2; }
.footer-nav-title { color: rgba(255,255,255,0.5); font-size: 0.72rem; font-weight: 700; letter-spacing: 0.15em; margin-bottom: 12px; text-transform: uppercase; }
.footer-nav { display: flex; flex-direction: column; gap: 8px; }
.footer-nav a { color: rgba(255,255,255,0.6); text-decoration: none; font-size: 0.85rem; transition: color 0.2s; }
.footer-nav a:hover { color: white; }
.footer-copy { font-size: 0.75rem; text-align: center; }
.demo-badge { display: block; text-align: center; margin-top: 8px; font-size: 0.68rem; color: rgba(255,255,255,0.2); }

@media (max-width: 900px) {
  header { padding: 0 20px; }
  nav a:not(.nav-cta) { display: none; }
  .section { padding: 64px 24px; }
  footer { padding: 48px 24px 28px; }
  .footer-inner { flex-direction: column; gap: 32px; }
}