# 随机位置随机颜色的点
    <script>
        setInterval(function() {
  var dot = document.createElement("div");
  dot.style.position = "fixed";
   = Math.random() * 100 + "%";
  dot.style.left = Math.random() * 100 + "%";
  dot.style.width = "10px";
  dot.style.height = "10px";
  dot.style.borderRadius = "50%";
  dot.style.backgroundColor = "#" + Math.floor(Math.random()*16777215).toString(16);
  document.body.appendChild(dot);
}, 1000);
    </script>


   
# 元素跳动
 <style>
        @keyframes jump {
  0% { transform: translateY(0); }
  50% { transform: translateY(-20px); }
  100% { transform: translateY(0); }
}

.jump-element {
  animation: jump 1s infinite;
}
    </style>