body {
  margin: 0;
  font-family: 'Georgia', serif;
  background-color: #f8f4ef;
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 20px;
}

.container {
  text-align: center;
}

.envelope {
  position: relative;
  width: 350px;
  height: 250px;
  background: url('envelope.png') no-repeat center/cover;
  border-radius: 8px;
  overflow: hidden;
  margin: auto;
}

.flap {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 50%;
  background: rgba(255,255,255,0.8);
  transform-origin: top center;
  transition: transform 1s;
  z-index: 2;
}

.card {
  position: absolute;
  bottom: 0;
  width: 100%;
  height: 100%;
  background: url('invitation.png') no-repeat center/cover;
  transform: translateY(100%);
  transition: transform 1s;
  z-index: 1;
}

.envelope.open .card {
  transform: translateY(0);
}

.envelope.open .flap {
  transform: rotateX(180deg);
}

.hint {
  margin: 20px 0;
  color: #666;
}

.text-section {
  max-width: 600px;
  background: white;
  padding: 20px;
  margin-top: 20px;
  border-radius: 10px;
  box-shadow: 0 4px 15px rgba(0,0,0,0.1);
}