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<head>
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  <title>网状粒子效果1</title>
  <style>
    html, body {
      margin: 0;
      padding: 0;
      height: 100%;
      overflow: hidden;
    }
  </style>
</head>
<body>
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<script>
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  var ctx = canvas.getContext("2d");

  resize();
  window.onresize = resize;

  function resize() {
    canvas.width = window.innerWidth || document.documentElement.clientWidth || documen