#introOverlay{
  position:fixed; inset:0; z-index:9999;
  background:rgba(10,8,30,.85); backdrop-filter:blur(10px);
  display:flex; align-items:center; justify-content:center;
  transition:opacity .7s ease;
}
.intro-card{
  background:#2b2350; border:1px solid #4a3f80; border-radius:16px;
  padding:40px 60px; text-align:center;
  box-shadow:0 20px 60px rgba(0,0,0,.5);
}
.intro-brand{ color:#fff; letter-spacing:4px; font:600 12px Arial, sans-serif; margin:0; }
.intro-logo{ color:#e8e6f5; font-family:Georgia, serif; font-size:22px; margin:24px 0 32px; line-height:1.4; }
.intro-logo span{ font-size:13px; letter-spacing:2px; }
#startJourneyBtn{
  background:linear-gradient(180deg,#a8e04a,#7fbf2a);
  border:none; border-radius:999px; padding:14px 36px;
  color:#1e2b05; font:700 13px Arial, sans-serif; letter-spacing:2px;
  cursor:pointer; box-shadow:0 0 18px rgba(160,220,60,.55);
  transition:transform .2s ease;
}
#startJourneyBtn:hover{ transform:scale(1.06); }
#musicToggle{
  position:fixed; right:20px; bottom:20px; z-index:9998;
  width:46px; height:46px; border-radius:50%;
  border:1px solid #4a3f80; background:#2b2350;
  font-size:18px; cursor:pointer; display:none;
}