/* RESET */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

/* Background luar (biar kaya layar HP di tengah laptop) */
body {
  background: #000;
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;
  font-family: sans-serif;
}

/* Frame layar HP */
.container {
  width: 390px;              /* Lebar standar HP */
  height: 100vh;
  max-height: 844px;         /* Biar proporsional */
  background: url("img/bg.png") no-repeat center center;
  background-size: cover;

  display: flex;
  justify-content: center;
  align-items: center;

  overflow: hidden;
  position: relative;

  border-radius: 30px;       /* Biar agak kaya HP */
  box-shadow: 0 0 40px rgba(0,0,0,0.8);
}

/* Amplop */
.envelope {
  width: 100%;
  max-width: 500px;
  cursor: pointer;
  transition: transform 0.3s ease;
}

/* Efek hover kecil */
.envelope:hover {
  transform: scale(1.05);
}

/* Animasi geter */
.shake {
  animation: shake 0.6s ease;
}

/* Keyframes geter */
@keyframes shake {
  0% { transform: rotate(0deg) scale(1); }
  20% { transform: rotate(6deg) scale(1.05); }
  40% { transform: rotate(-6deg) scale(1.08); }
  60% { transform: rotate(4deg) scale(1.05); }
  80% { transform: rotate(-3deg) scale(1.08); }
  100% { transform: rotate(0deg) scale(1.1); }
}