:root{
  --bg:#000;
  --text:#fff;
  --muted:rgba(255,255,255,.78);
  --muted2:rgba(255,255,255,.62);
  --border:rgba(255,255,255,.18);
  --shadow:0 18px 60px rgba(0,0,0,.55);
  --radius:18px;
}

*{ box-sizing:border-box; }
html,body{ height:100%; }

body{
  margin:0;
  background:var(--bg);
  color:var(--text);
  font-family: system-ui, -apple-system, "Hiragino Kaku Gothic ProN", "Noto Sans JP", "Yu Gothic", sans-serif;
  line-height:1.8;
  letter-spacing:.02em;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

/* subtle glow */
body::before{
  content:"";
  position:fixed;
  inset:-20%;
  background:
    radial-gradient(circle at 20% 10%, rgba(255,255,255,.08), transparent 35%),
    radial-gradient(circle at 80% 30%, rgba(255,255,255,.06), transparent 40%),
    radial-gradient(circle at 50% 90%, rgba(255,255,255,.05), transparent 45%);
  pointer-events:none;
  filter: blur(2px);
}

.wrap{
  min-height:100%;
  display:flex;
  align-items:center;
  justify-content:center;
  padding:56px 20px;
  position:relative;
  z-index:1;
}

.card{
  width:min(900px, 100%);
  border:1px solid var(--border);
  border-radius:var(--radius);
  background:rgba(255,255,255,.03);
  box-shadow:var(--shadow);
  padding:46px 54px;
  backdrop-filter: blur(10px);
}

.brand{
  display:flex;
  justify-content:center;
  margin-bottom:10px;
}
.brand img{
  width:220px;
  max-width:70%;
  height:auto;
  display:block;
}

.head{
  text-align:center;
  margin-bottom:10px;
}
.kicker{
  margin:0 0 8px;
  color:var(--muted2);
  font-size:12px;
  letter-spacing:.14em;
}

h1{
  margin:0 0 10px;
  font-size:28px;
  letter-spacing:.08em;
}

.lead{
  color:var(--muted);
  max-width:48em;
  margin:0 auto 18px;
  text-align:center;
  font-size:16px;
}

.divider{
  height:1px;
  background:rgba(255,255,255,.14);
  margin:26px auto;
  width:min(560px, 92%);
}

.cta{
  text-align:center;
}

.btn{
  display:inline-flex;
  justify-content:center;
  align-items:center;
  padding:16px 22px;
  min-width:340px;
  border-radius:999px;
  border:1px solid rgba(255,255,255,.28);
  background:rgba(255,255,255,.10);
  color:#fff;
  text-decoration:none;
  font-weight:700;
  letter-spacing:.06em;
  transition: transform .12s ease, background .18s ease, border-color .18s ease;
  user-select:none;
}

.btn:hover{
  background:rgba(255,255,255,.18);
  border-color:rgba(255,255,255,.40);
  transform: translateY(-1px);
}
.btn:active{
  transform: translateY(0);
}

.note-mini{
  margin-top:10px;
  font-size:12px;
  color:var(--muted2);
}

.notes{
  margin:26px auto 0;
  max-width:56em;
  color:var(--muted2);
}

.notes h2{
  font-size:14px;
  letter-spacing:.08em;
  margin:0 0 10px;
  color:rgba(255,255,255,.85);
}

.notes ul{
  margin:0;
  padding-left:1.2em;
}
.notes li{
  margin:6px 0;
}

.footer{
  margin-top:28px;
  padding-top:18px;
  border-top:1px solid rgba(255,255,255,.12);
  text-align:center;
  font-size:12px;
  color:rgba(255,255,255,.55);
}
.footer div{
  margin:4px 0;
}

/* ===== PC ===== */
@media (min-width: 769px){
  h1{ font-size:30px; }
}

/* ===== Smartphone ===== */
@media (max-width: 768px){
  .wrap{ padding:34px 14px; }
  .card{ padding:28px 18px; border-radius:16px; }
  .brand img{ width:180px; }

  h1{ font-size:22px; }
  .lead{
    font-size:14px;
    text-align:left;
    margin-bottom:14px;
  }

  .btn{
    width:100%;
    min-width:0;
    padding:15px 16px;
    font-size:14px;
  }

  .notes{ font-size:12px; }
}

/* Accessibility */
@media (prefers-reduced-motion: reduce){
  .btn{ transition:none; }
  .btn:hover{ transform:none; }
}