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

body {
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 100vh;
  background-color: hsl(0, 0%, 15%);
}

.postcard {
  position: relative;
  width: 600px;
  height: 400px;
  overflow: hidden;
  border-radius: 16px;
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.5);
}

.sky {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 65%;
  /* TODO: background sky gradient */
  background: #ffa600;
  background: linear-gradient(210deg,rgba(255, 166, 0, 1) 0%, rgba(54, 37, 0, 1) 100%);
}

.sun {
  position: absolute;
  top: 60px;
  right: 80px;
  width: 80px;
  height: 80px;
  /* TODO: sun shape and glow */
  background-color: hsl(45, 100%, 70%);
  border-radius: 50%;
  box-shadow: 0 0 40px 20px hsl(45, 100%, 80%);
  /* TODO: sun color experiment */
  animation: sunPulse 2s ease-in-out infinite alternate;
}

@keyframes sunPulse {
  0% {
    transform: scale(1);
    opacity: 0.7;
  }

  100% {
    transform: scale(1.15);
    opacity: 1;
  }
}

.hills {
  position: absolute;
  bottom: 30%;
  left: -10%;
  width: 120%;
  height: 45%;
  /* TODO: hills shape */
  background: radial-gradient(
    ellipse 120% 60% at 50% 100%,
    hsl(120, 50%, 35%),
    hsl(120, 40%, 25%)
  );
  border-radius: 50% 50% 0 0;
}

.water {
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 32%;
  /* TODO: water color and transparency */
  background: linear-gradient(
    to bottom,
    hsla(210, 70%, 50%, 0.85),
    hsla(210, 60%, 30%, 1)
  );
}

.text-overlay {
  position: absolute;
  bottom: 40px;
  left: 0;
  width: 100%;
  text-align: center;
  font-family: Georgia, serif;
  /* TODO: text styling and shadow */
  /* TODO: text color experiment */
}