.letter-page {
  position: relative;
  width: 100vw;
  height: 100vh;
  background-image: url('images/bg1.jpg'); /* your background image */
  background-size: cover;
  background-position: center;
  display: flex;
  justify-content: center;
  align-items: center;
}

.letter-image {
  max-width: 70%;
  max-height: 80%;
  box-shadow: 0 10px 25px rgba(0,0,0,0.3);
  border-radius: 12px;
}

/* back button */
.back-button {
  position: absolute;
  top: 20px;
  left: 20px;
  text-decoration: none;
  color: #fff;
  font-size: 18px;
  background: rgba(255, 160, 200, 0.8);
  padding: 6px 12px;
  border-radius: 8px;
  transition: background 0.3s ease;
}

.back-button:hover {
  background: rgba(255, 160, 200, 1);
}