demo.html

<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta
      name="viewport"
      content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0"
    />
    <meta http-equiv="X-UA-Compatible" content="ie=edge" />
    <title>fire</title>
    <style>
      h1 {
        font-size: 24px;
        text-align: center;
        color: red;
      }

      .hid {
        position: absolute;
        left: -9999px;
        top: -9999px;
      }

      #fire {
        display: block;
        margin: 0 auto;
      }
    </style>
  </head>
  <body>
    <h1>🔥火焰🔥</h1>
    <canvas id="fire" width="1024" height="400"></canvas>
    <canvas id="noise" width="1024" height="2048" class="hid"></canvas>

    <script type="module" src="./src/fire.js"></script>
  
  </body>
</html>