body {
  font-family: "Poppins", sans-serif;
  background: linear-gradient(135deg, #007bff, #00b894);
  height: 100vh;
  margin: 0;
  display: flex;
  justify-content: center;
  align-items: center;
}

.form-wrapper {
  perspective: 1000px;
}

.card {
  width: 360px;
  height: 460px;
  position: relative;
  transform-style: preserve-3d;
  transition: transform 0.9s;
}

.card.flip {
  transform: rotateY(180deg);
}

.front, .back {
  background: #fff;
  border-radius: 20px;
  box-shadow: 0 5px 30px rgba(0, 0, 0, 0.15);
  position: absolute;
  width: 100%;
  height: 100%;
  padding: 30px;
  text-align: center;
  backface-visibility: hidden;
}

.back {
  transform: rotateY(180deg);
}

h2 {
  color: #333;
  margin-bottom: 20px;
  font-weight: 600;
}

input {
  width: 100%;
  padding: 12px;
  margin: 8px 0;
  border: 1px solid #ccc;
  border-radius: 8px;
  outline: none;
  transition: 0.3s;
}

input:focus {
  border-color: #007bff;
  box-shadow: 0 0 5px rgba(0, 123, 255, 0.4);
}

button {
  width: 100%;
  padding: 12px;
  margin-top: 10px;
  border: none;
  border-radius: 8px;
  background: #007bff;
  color: white;
  font-size: 16px;
  cursor: pointer;
  transition: background 0.3s;
}

button:hover {
  background: #0056b3;
}

.divider {
  margin: 15px 0;
  color: #aaa;
  font-size: 14px;
}

.toggle {
  color: #007bff;
  cursor: pointer;
  margin-top: 15px;
  font-weight: 500;
}

#msg, #reg-msg {
  color: red;
  font-size: 14px;
  margin-top: 10px;
}