:root {
  --bg: #fff;
  --card-w: min(88vw, 340px);
  --card-h: 460px;
  --gold: #f59e0b;
  --gold-glow: rgba(245, 158, 11, 0.45);
  --accent: #6366f1;
}
    
* { box-sizing: border-box; margin: 0; padding: 0; }
    
body {
  min-height: 100vh;
  display: grid;
  place-items: center;
  font-family: system-ui, -apple-system, sans-serif;
  color: #fff;
  overflow: hidden;
  perspective: 1200px;
}
    
#open { display: none; }
.card-box {
  position: relative;
  width: var(--card-w);
  height: var(--card-h);
  transform-style: preserve-3d;
  transition: transform 0.8s cubic-bezier(0.34, 1.56, 0.64, 1);
  cursor: pointer;
}
    
#open:checked ~ .card-box, .card-box:hover {
  transform: rotateX(10deg) rotateY(-18deg) scale(1.03);
}
    
.inner-card, .cover {
  position: absolute;
  inset: 0;
  border-radius: 22px;
  padding: 2.2rem 1.6rem;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  box-shadow: 0px 0px 20px rgba(0, 0, 0, 0.6);
}
    
.inner-card {
  background: linear-gradient(145deg, #181d38, #0e1124);
  border: 1.5px solid rgba(255, 255, 255, 0.12);
  z-index: 1;
}
    
.inner-card .badge {
  align-self: flex-start;
  background: rgba(245, 158, 11, 0.15);
  border: 1px solid var(--gold);
  color: #fde68a;
  padding: 0.35rem 0.8rem;
  border-radius: 99px;
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.1em;
}
    
.inner-card h2 {
  font-size: 1.65rem;
  line-height: 1.25;
  background: linear-gradient(to right, #fff, #a5b4fc);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}
    
.inner-card p { font-size: 0.9rem; color: #94a3b8; line-height: 1.6; }
.inner-card .btn {
  background: linear-gradient(135deg, #6366f1, #a855f7);
  border: none;
  padding: 0.85rem;
  border-radius: 12px;
  color: #fff;
  font-weight: 600;
  text-align: center;
}
    
.cover {
  background: linear-gradient(135deg, #2e1065 0%, #1e1b4b 60%, #0f172a 100%);
  border: 1.5px solid white;
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 20px;
  transform-origin: left center;
  transform-style: preserve-3d;
  transition: transform 0.9s cubic-bezier(0.25, 1, 0.5, 1), box-shadow 0.6s;
  z-index: 2;
  font-family: serif;
}
    
#open:checked ~ .card-box .cover, .card-box:hover .cover {
  transform: rotateY(-145deg);
  box-shadow: 0px 0px 20px rgba(0, 0, 0, 0.6);
}

.cover h3 { 
  font-size: 1.4rem; 
  text-align: center;
}
    
.cover .hint {
  text-align: center; 
  font-size: 0.8rem; 
  color: #cbd5e1;
  opacity: 0.8; }
    
@keyframes pulse { to { transform: scale(1.08); box-shadow: 0 0 45px #ec4899; } }