:root {
  --bg: #0e1320;
  --bg-soft: #161d2e;
  --fg: #e8edf6;
  --muted: #97a3b8;
  --accent: #5b8cff;
  --accent-2: #7af0d0;
  --radius: 16px;
  --max: 1080px;
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
}

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

html { scroll-behavior: smooth; }

body {
  font-family: -apple-system, "Segoe UI", "Hiragino Sans", "Noto Sans JP", sans-serif;
  background: var(--bg);
  color: var(--fg);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

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

/* ---------- ナビ ---------- */
.nav {
  position: fixed;
  inset: 0 0 auto 0;
  display: flex;
  align-items: center;
  gap: 24px;
  padding: 18px clamp(16px, 5vw, 48px);
  z-index: 50;
  transition: background 0.4s var(--ease), box-shadow 0.4s var(--ease),
    padding 0.4s var(--ease);
}
.nav.is-scrolled {
  background: rgba(14, 19, 32, 0.82);
  backdrop-filter: blur(12px);
  box-shadow: 0 1px 0 rgba(255, 255, 255, 0.06);
  padding-top: 12px;
  padding-bottom: 12px;
}
.nav__logo { font-weight: 800; font-size: 1.2rem; letter-spacing: -0.02em; }
.nav__logo span { color: var(--accent); }
.nav__links { display: flex; gap: 22px; margin-left: auto; color: var(--muted); }
.nav__links a { position: relative; transition: color 0.25s var(--ease); }
.nav__links a::after {
  content: ""; position: absolute; left: 0; bottom: -4px;
  width: 100%; height: 2px; background: var(--accent);
  transform: scaleX(0); transform-origin: left;
  transition: transform 0.3s var(--ease);
}
.nav__links a:hover { color: var(--fg); }
.nav__links a:hover::after { transform: scaleX(1); }
.nav__cta {
  padding: 9px 18px; border-radius: 999px;
  background: var(--accent); color: #fff; font-weight: 700;
  transition: transform 0.25s var(--ease), box-shadow 0.25s var(--ease);
}
.nav__cta:hover { transform: translateY(-2px); box-shadow: 0 8px 24px rgba(91, 140, 255, 0.4); }

/* ---------- ヒーロー ---------- */
.hero {
  position: relative; min-height: 100vh;
  display: grid; place-items: center;
  padding: 120px 24px 80px; text-align: center; overflow: hidden;
}
.hero__bg {
  position: absolute; inset: -20%;
  background:
    radial-gradient(40% 40% at 20% 20%, rgba(91, 140, 255, 0.45), transparent 70%),
    radial-gradient(45% 45% at 80% 30%, rgba(122, 240, 208, 0.30), transparent 70%),
    radial-gradient(50% 50% at 50% 90%, rgba(91, 140, 255, 0.25), transparent 70%);
  filter: blur(20px);
  animation: drift 18s ease-in-out infinite alternate;
}
@keyframes drift {
  0%   { transform: translate3d(0, 0, 0) scale(1); }
  100% { transform: translate3d(0, -4%, 0) scale(1.12); }
}
.hero__inner { position: relative; max-width: 760px; }
.hero__eyebrow {
  letter-spacing: 0.3em; font-size: 0.72rem; color: var(--accent-2);
  font-weight: 700; margin-bottom: 18px;
}
.hero__title {
  font-size: clamp(2.4rem, 7vw, 4.4rem); line-height: 1.12;
  letter-spacing: -0.03em; font-weight: 800; margin-bottom: 22px;
}
.hero__lead { color: var(--muted); font-size: clamp(1rem, 2.4vw, 1.2rem); margin-bottom: 34px; }
.hero__actions { display: flex; gap: 14px; justify-content: center; flex-wrap: wrap; }
.hero__scroll {
  position: absolute; left: 50%; bottom: -40px; transform: translateX(-50%);
  color: var(--muted); font-size: 0.72rem; letter-spacing: 0.2em;
  display: grid; justify-items: center; gap: 8px;
}
.hero__scroll span {
  width: 22px; height: 34px; border: 2px solid var(--muted); border-radius: 12px;
  position: relative;
}
.hero__scroll span::after {
  content: ""; position: absolute; left: 50%; top: 7px; transform: translateX(-50%);
  width: 4px; height: 7px; border-radius: 2px; background: var(--muted);
  animation: wheel 1.6s var(--ease) infinite;
}
@keyframes wheel { 0% { opacity: 1; top: 7px; } 100% { opacity: 0; top: 18px; } }

/* ---------- ボタン ---------- */
.btn {
  display: inline-block; padding: 13px 26px; border-radius: 999px;
  font-weight: 700; transition: transform 0.25s var(--ease), box-shadow 0.25s var(--ease),
    background 0.25s var(--ease);
}
.btn--primary { background: var(--accent); color: #fff; }
.btn--primary:hover { transform: translateY(-2px); box-shadow: 0 12px 30px rgba(91, 140, 255, 0.45); }
.btn--ghost { border: 1px solid rgba(255, 255, 255, 0.18); color: var(--fg); }
.btn--ghost:hover { transform: translateY(-2px); background: rgba(255, 255, 255, 0.06); }

/* ---------- セクション共通 ---------- */
.section__title {
  text-align: center; font-size: clamp(1.6rem, 4vw, 2.4rem);
  letter-spacing: -0.02em; margin-bottom: 48px;
}
.features, .stats, .pricing { padding: clamp(70px, 12vw, 130px) clamp(16px, 5vw, 48px); max-width: var(--max); margin: 0 auto; }

/* ---------- 特長カード ---------- */
.features__grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 22px; }
.card {
  background: var(--bg-soft); border: 1px solid rgba(255, 255, 255, 0.06);
  border-radius: var(--radius); padding: 30px 26px;
  transition: transform 0.35s var(--ease), border-color 0.35s var(--ease);
}
.card:hover { transform: translateY(-6px); border-color: rgba(91, 140, 255, 0.5); }
.card__icon { font-size: 2rem; margin-bottom: 14px; }
.card h3 { margin-bottom: 8px; font-size: 1.15rem; }
.card p { color: var(--muted); }

/* ---------- 数字 ---------- */
.stats { text-align: center; }
.stats__grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(180px, 1fr)); gap: 28px; }
.stat__num {
  display: block; font-size: clamp(2.2rem, 6vw, 3.4rem); font-weight: 800;
  letter-spacing: -0.02em;
  background: linear-gradient(120deg, var(--accent), var(--accent-2));
  -webkit-background-clip: text; background-clip: text; color: transparent;
}
.stat__label { color: var(--muted); font-size: 0.9rem; }

/* ---------- 料金 ---------- */
.pricing__grid {
  display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 22px; max-width: 720px; margin: 0 auto;
}
.plan {
  position: relative; background: var(--bg-soft);
  border: 1px solid rgba(255, 255, 255, 0.08); border-radius: var(--radius);
  padding: 32px 28px; text-align: center;
  transition: transform 0.35s var(--ease);
}
.plan:hover { transform: translateY(-6px); }
.plan--featured { border-color: rgba(91, 140, 255, 0.6); box-shadow: 0 20px 50px rgba(91, 140, 255, 0.18); }
.plan__badge {
  position: absolute; top: -12px; left: 50%; transform: translateX(-50%);
  background: var(--accent); color: #fff; font-size: 0.72rem; font-weight: 700;
  padding: 4px 12px; border-radius: 999px;
}
.plan__price { font-size: 2.2rem; font-weight: 800; margin: 10px 0 18px; }
.plan__price span { font-size: 0.95rem; color: var(--muted); font-weight: 600; }
.plan ul { list-style: none; margin-bottom: 24px; color: var(--muted); display: grid; gap: 8px; }

/* ---------- フッター ---------- */
.footer {
  text-align: center; padding: 50px 24px; color: var(--muted);
  font-size: 0.85rem; border-top: 1px solid rgba(255, 255, 255, 0.06);
}
.footer strong { color: var(--accent-2); }

/* ---------- トップへ戻る ---------- */
.totop {
  position: fixed; right: 22px; bottom: 22px; width: 46px; height: 46px;
  border: none; border-radius: 50%; background: var(--accent); color: #fff;
  font-size: 1.1rem; cursor: pointer; opacity: 0; pointer-events: none;
  transform: translateY(12px); transition: opacity 0.3s var(--ease), transform 0.3s var(--ease);
}
.totop.is-visible { opacity: 1; pointer-events: auto; transform: translateY(0); }
.totop:hover { transform: translateY(-3px); }

/* ---------- スクロール・リビール ---------- */
.reveal {
  opacity: 0; transform: translateY(26px);
  transition: opacity 0.7s var(--ease), transform 0.7s var(--ease);
  transition-delay: calc(var(--i, 0) * 90ms);
}
.reveal.is-visible { opacity: 1; transform: translateY(0); }

@media (prefers-reduced-motion: reduce) {
  *, *::after { animation: none !important; transition: none !important; }
  .reveal { opacity: 1; transform: none; }
}