body {
  font-family: Arial;
  margin: 0;
  padding-top: 50px;
}

.menu {
  position: fixed;
  top: 0;
  width: 100%;
  background: #ddd;
  display: flex;
  justify-content: center;
  gap: 20px;
  padding: 10px;
}
.menu a {
  text-decoration: none;
  color: black;
}
.menu a.active {
  color: red;
  font-weight: bold;
}

section {
  height: 100vh;
  padding: 50px;
  border-bottom: 1px solid #ccc;
}

.dark {
  background: #222;
  color: #fff;
}

.box {
  opacity: 0;
  transform: translateY(30px);
  transition: 0.6s;
  background: lightblue;
  margin: 20px;
  padding: 30px;
}
.box.show {
  opacity: 1;
  transform: translateY(0);
}

.jump.animate {
  animation: jump 0.4s;
}
@keyframes jump {
  0% { transform: translateY(0); }
  50% { transform: translateY(-10px); }
  100% { transform: translateY(0); }
}

.circle {
  position: fixed;     
  width: 30px;
  height: 30px;
  background: red;
  border-radius: 50%;
  pointer-events: none;   
  z-index: 9999;          
}