页面自适应

body {
   //设置页面大小
  width: 1920px;
  height: 1080px;
  //关键
  transform-origin: left top 0px;
}

在浏览器resize时刷新并调用方法：

body_resize = () => {
  let wid = 1920;
  let hei = 1080;
  if (window.innerWidth == wid && window.innerHeight == hei) return;
  document.body.style.transform =
    "scale(" +
    window.innerWidth / wid +
    "," +
    window.innerHeight / hei +
    ")";
  }