* {
  box-sizing: border-box;
}
.flip-container {
  font-family: system-ui, "Segoe UI", Roboto, Helvetica, Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol";
  perspective: 1000px;
  width: 320px;
  height: 200px;
  margin: 0 auto;
}
.flipper {
  position: relative;
  width: 100%;
  height: 100%;
  transition: transform 0.6s;
  transform-style: preserve-3d;
}
.flip-container:hover .flipper {
  transform: rotateY(180deg);
}
.front, .back {
  position: absolute;
  width: 100%;
  height: 100%;
  backface-visibility: hidden;
  border-radius: 16px;
  box-shadow: 0 15px 35px rgba(0,0,0,0.2);
  color: white;
  padding: 20px;
  box-sizing: border-box;
}
.front {
  background: linear-gradient(135deg, #1e293b, #0f172a);
}
.back {
  background: linear-gradient(135deg, #1e293b, #0f172a);
  transform: rotateY(180deg);
}
/* Front Details */
.chip {
  width: 40px;
  height: 30px;
  background: #fbbf24;
  border-radius: 5px;
  margin-bottom: 40px;
}
.card-num {
  font-size: 1.4rem;
  letter-spacing: 2px;
  font-family: monospace;
  margin-bottom: 25px;
}
.card-name {
  text-transform: uppercase;
  font-size: 0.8rem;
}
.card-exp {
  position: absolute;
  bottom: 20px;
  right: 80px;
  font-size: 0.9rem;
}
.card-logo {
  position: absolute;
  bottom: 20px;
  right: 20px;
  font-weight: 800;
  font-style: italic;
  font-size: 1.2rem;
}
/* Back Details */
.magnetic-strip {
  background: #000;
  height: 40px;
  width: 100%;
  position: absolute;
  left: 0;
  top: 20px;
}
.cvv-box {
  background: #fff;
  color: #000;
  width: 100%;
  margin-top: 60px;
  padding: 10px;
  border-radius: 4px;
  text-align: right;
  font-family: monospace;
  position: relative;
}
.cvv-box span {
  position: absolute;
  top: -20px;
  right: 0;
  color: white;
  font-size: 0.7rem;
}