body {
  margin: 0;
  font-family: Arial;
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;

  background: linear-gradient(120deg, #f5f5dc, #87ceeb, #001f3f);
  background-size: 300% 300%;
  animation: bg 8s infinite;
}

/* BACKGROUND ANIMATION */
@keyframes bg {
  0% {
    background-position: 0% 50%;
  }
  50% {
    background-position: 100% 50%;
  }
  100% {
    background-position: 0% 50%;
  }
}

.container {
  background: linear-gradient(90deg, #87ceeb, #001f3f);
  padding: 25px;
  border-radius: 12px;
  width: 300px;
  text-align: center;
  box-shadow: 0 10px 25px rgba(0, 0, 0, 0.2);
}

/* LISTS */
ul {
  list-style: none;
  padding: 0;
  margin: 0;
}

li {
  padding: 12px;
  margin: 8px 0;
  background: #001f3f;
  color: white;
  border-radius: 8px;
  cursor: pointer;
  transition: 0.3s;
}

li:hover {
  background: #87ceeb;
  color: #001f3f;
}

/* HIDE LEVELS INITIALLY */
.level-list {
  display: none;
}