/* =========================
   Base
   ========================= */
:root {
  --color-bg: #0b1020;
  --color-surface: #0f172a;
  --color-muted: #94a3b8;
  --color-text: #e2e8f0;
  --color-primary: #0ea5e9;
  --color-primary-700: #0284c7;
  --max-w: 1080px;
  --radius: 12px;
  --shadow: 0 10px 30px rgba(2, 132, 199, 0.2);
}

* { box-sizing: border-box; }
html, body {
  margin: 0;
  padding: 0;
  color: var(--color-text);
  background: linear-gradient(180deg, #04060f 0%, var(--color-bg) 100%);
  font-family: system-ui, -apple-system, Segoe UI, Roboto, Noto Sans JP, Helvetica, Arial, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol";
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  scroll-behavior: smooth;
}

.container {
  width: 100%;
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 20px;
}

h1, h2, h3 {
  line-height: 1.25;
  margin: 0 0 12px;
}

h1 { font-size: clamp(28px, 4vw, 42px); }
h2 { font-size: clamp(22px, 3vw, 28px); }
h3 { font-size: clamp(18px, 2.5vw, 22px); }
p { margin: 0 0 14px; }

.list { padding-left: 18px; margin: 10px 0 0; }
.list li { margin: 6px 0; }
.list.num { list-style: decimal; }
.note { color: var(--color-muted); }
.muted { color: var(--color-muted); font-size: 14px; }

/* =========================
   Header / Nav
   ========================= */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(15, 23, 42, 0.7);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid rgba(148, 163, 184, 0.12);
}
.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--color-text);
  text-decoration: none;
  font-weight: 700;
  letter-spacing: 0.2px;
}
.nav {
  display: flex;
  gap: 18px;
}
.nav a {
  color: var(--color-text);
  text-decoration: none;
  opacity: 0.9;
}
.nav a:hover { opacity: 1; }

.nav-toggle {
  display: none;
  width: 40px;
  height: 40px;
  border: 1px solid rgba(148,163,184,.25);
  border-radius: 8px;
  background: transparent;
  align-items: center;
  justify-content: center;
  gap: 3px;
}
.nav-toggle span {
  display: block;
  width: 18px;
  height: 2px;
  background: var(--color-text);
}

@media (max-width: 840px) {
  .nav { 
    position: absolute;
    right: 20px;
    top: 64px;
    flex-direction: column;
    background: var(--color-surface);
    border: 1px solid rgba(148, 163, 184, 0.12);
    border-radius: 12px;
    padding: 12px;
    display: none;
    box-shadow: var(--shadow);
  }
  .nav.is-open { display: flex; }
  .nav-toggle { display: inline-flex; }
}

/* =========================
   Hero
   ========================= */
.hero {
  padding: 64px 0 24px;
  background:
    radial-gradient(1200px 400px at 10% -10%, rgba(14, 165, 233, 0.25), transparent 60%),
    radial-gradient(800px 400px at 90% -10%, rgba(99, 102, 241, 0.22), transparent 60%);
}
.hero-inner {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 32px;
  align-items: center;
}
.hero-copy p { color: var(--color-muted); font-size: 18px; }
.hero-cta { display: flex; gap: 12px; margin-top: 18px; }
.hero-logo {
  width: min(280px, 70%);
  display: block;
  margin-left: auto;
  opacity: 0.95;
  filter: drop-shadow(0 20px 30px rgba(14,165,233,.15));
}
@media (max-width: 840px) {
  .hero-inner { grid-template-columns: 1fr; }
  .hero { padding: 42px 0 6px; }
  .hero-logo { margin: 12px auto 0; width: 160px; }
}

/* =========================
   Sections
   ========================= */
.section { padding: 54px 0; }
.section.alt {
  background: linear-gradient(180deg, rgba(148, 163, 184, 0.05), rgba(148, 163, 184, 0.02));
  border-top: 1px solid rgba(148,163,184,.08);
  border-bottom: 1px solid rgba(148,163,184,.08);
}

.cards {
  margin-top: 18px;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}
.card {
  background: rgba(15, 23, 42, 0.7);
  border: 1px solid rgba(148, 163, 184, 0.12);
  border-radius: var(--radius);
  padding: 18px;
  box-shadow: var(--shadow);
}
.card p { color: var(--color-muted); }
@media (max-width: 960px) {
  .cards { grid-template-columns: 1fr; }
}

/* =========================
   Buttons
   ========================= */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  height: 42px;
  padding: 0 14px;
  border-radius: 10px;
  border: 1px solid rgba(148,163,184,.2);
  color: var(--color-text);
  text-decoration: none;
  background: transparent;
  transition: transform .08s ease, background .2s ease, border-color .2s ease, color .2s ease;
  will-change: transform;
}
.btn:hover { transform: translateY(-1px); }
.btn:active { transform: translateY(0); }
.btn-primary {
  background: linear-gradient(180deg, var(--color-primary), var(--color-primary-700));
  border-color: rgba(14,165,233,.6);
  color: #fff;
  box-shadow: 0 10px 30px rgba(14,165,233,.25);
}
.btn-ghost {
  background: rgba(148,163,184,.08);
}

.contact-actions { display: flex; gap: 12px; flex-wrap: wrap; }

/* =========================
   Footer
   ========================= */
.site-footer {
  padding: 28px 0 36px;
  color: var(--color-muted);
  border-top: 1px solid rgba(148, 163, 184, 0.12);
  background: rgba(15, 23, 42, 0.5);
}