:root{
  --bg: #0b0f16;
  --panel: #101827;
  --card: #121c2c;
  --text: #eaf0fb;
  --muted: #b7c2d9;
  --line: #24324b;
  --accent: #7aa7ff;
  --accent2: #79f2c0;
  --warn: #ffd36f;

  --r: 16px;
  --shadow: 0 12px 30px rgba(0,0,0,.35);
  --max: 1120px;
}

*{ box-sizing: border-box; }
html,body{ margin:0; padding:0; }
body{
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, "Noto Sans JP", "Hiragino Sans", "Yu Gothic", "Meiryo", sans-serif;
  background:
    radial-gradient(1200px 600px at 18% 0%, rgba(122,167,255,.22), transparent 60%),
    radial-gradient(900px 520px at 84% 10%, rgba(121,242,192,.14), transparent 55%),
    var(--bg);
  color: var(--text);
  line-height: 1.75;
}

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

.container{
  max-width: var(--max);
  margin: 0 auto;
  padding: 0 18px;
}

.muted{ color: var(--muted); }
.small{ font-size: .92rem; }

/* Header */
.site-header{
  position: sticky;
  top: 0;
  z-index: 1000;
  background: rgba(11,15,22,.72);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid rgba(36,50,75,.55);
}

.header-inner{
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap: 12px;
  height: 64px;
}

.brand{
  display:flex;
  align-items:center;
  gap: 10px;
  font-weight: 900;
  letter-spacing: .2px;
}

.brand-mark{
  width: 36px;
  height: 36px;
  display:inline-flex;
  align-items:center;
  justify-content:center;
  border-radius: 10px;
  background: linear-gradient(135deg, rgba(122,167,255,.95), rgba(121,242,192,.7));
  color: #07101a;
  font-weight: 900;
}

.brand-name{
  font-size: 1rem;
  white-space: nowrap;
}

.nav{
  display:flex;
  gap: 14px;
  flex-wrap: wrap;
  align-items:center;
  justify-content:flex-end;
}

.nav a{
  color: var(--muted);
  padding: 8px 10px;
  border-radius: 12px;
  border: 1px solid transparent;
}

.nav a:hover{
  color: var(--text);
  text-decoration: none;
  background: rgba(18,28,44,.65);
  border-color: rgba(36,50,75,.65);
}

.nav-cta{
  color: var(--text) !important;
  background: linear-gradient(135deg, rgba(122,167,255,.25), rgba(121,242,192,.16));
  border-color: rgba(122,167,255,.35) !important;
}

/* Hero */
.hero{
  padding: 56px 0 28px;
}

.hero-inner{
  display:grid;
  grid-template-columns: 1.1fr .9fr;
  gap: 18px;
  align-items: start;
}

.badge{
  display:inline-flex;
  align-items:center;
  gap: 8px;
  padding: 6px 10px;
  border-radius: 999px;
  background: rgba(255,211,111,.12);
  border: 1px solid rgba(255,211,111,.25);
  color: var(--warn);
  font-size: .9rem;
}

.hero-title{
  margin: 14px 0 10px;
  font-size: 2.2rem;
  line-height: 1.25;
  font-weight: 950;
}

.hero-lead{
  margin: 0 0 14px;
  color: var(--muted);
}

.hero-note{
  margin-top: 14px;
  padding: 14px 14px;
  border-radius: var(--r);
  border: 1px solid rgba(36,50,75,.70);
  background: rgba(16,24,39,.55);
  box-shadow: var(--shadow);
}

.note-title{
  margin: 0 0 6px;
  font-weight: 900;
}

.note-text{
  margin: 0;
  color: var(--muted);
}

/* Sections */
.section{
  padding: 46px 0;
}

.section-alt{
  background: rgba(16,24,39,.45);
  border-top: 1px solid rgba(36,50,75,.45);
  border-bottom: 1px solid rgba(36,50,75,.45);
}

.section-head{
  margin-bottom: 16px;
}

.section-title{
  margin: 0 0 6px;
  font-size: 1.55rem;
  font-weight: 950;
}

.section-sub{
  margin: 0;
  color: var(--muted);
}

/* Cards / Grid */
.grid{
  display:grid;
  gap: 14px;
}

.grid-2{
  grid-template-columns: repeat(2, minmax(0,1fr));
}

.grid-3{
  grid-template-columns: repeat(3, minmax(0,1fr));
}

.card{
  background: rgba(18,28,44,.72);
  border: 1px solid rgba(36,50,75,.72);
  border-radius: var(--r);
  padding: 16px 16px;
  box-shadow: var(--shadow);
}

.card-title{
  margin: 0 0 10px;
  font-weight: 950;
}

.card-text{
  margin: 10px 0 0;
  color: var(--muted);
}

.card-text:first-of-type{
  margin-top: 0;
}

.card-foot{
  margin: 12px 0 0;
  color: var(--muted);
}

.list{
  margin: 0;
  padding-left: 18px;
  color: var(--muted);
}

.list li{
  margin: 6px 0;
}

/* Buttons */
.btn{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  padding: 11px 14px;
  border-radius: 14px;
  border: 1px solid rgba(122,167,255,.45);
  background: linear-gradient(135deg, rgba(122,167,255,.22), rgba(121,242,192,.12));
  color: var(--text);
  font-weight: 900;
  text-decoration: none;
  transition: transform .08s ease, background .15s ease;
}

.btn:hover{
  transform: translateY(-1px);
  text-decoration: none;
  background: linear-gradient(135deg, rgba(122,167,255,.30), rgba(121,242,192,.16));
}

.btn-ghost{
  border-color: rgba(183,194,217,.25);
  background: rgba(18,28,44,.55);
  color: var(--muted);
}

/* Fineprint */
.fineprint{
  margin-top: 14px;
  padding-top: 10px;
  border-top: 1px solid rgba(36,50,75,.45);
}

/* Footer */
.site-footer{
  padding: 26px 0 38px;
}

.footer-inner{
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap: 10px;
  border-top: 1px solid rgba(36,50,75,.45);
  padding-top: 16px;
}

@media (max-width: 920px){
  .hero-inner{ grid-template-columns: 1fr; }
  .grid-3{ grid-template-columns: 1fr; }
  .grid-2{ grid-template-columns: 1fr; }
  .nav{ display:none; } /* スマホはナビ非表示（必要なら後で追加） */
  .hero-title{ font-size: 2rem; }
}