Set the background image in Vue-cli to cover the entire screen

 Choose one of three CSS setting methods

<template>
  <div class="wrapper">

  </div>
</template>

<style>
.wrapper {

  /*1.背景全屏固定,使用fixed定位，内容完全显示且可滚动查看*/

  /* 
  position: fixed;
  height: 100%;
  width: 100%;
  background: url("../assets/dd.png") no-repeat;
  background-size:100% 100%;
  overflow-y: scroll;
  overflow-x: hidden;
  */

  /*2.线性渐变色背景全屏缩放大小，不用定位,内容完全显示且可滚动查看*/
 
  /*
  background: linear-gradient(to bottom right, blue, red) center center no-repeat;
  background-size: 100% 100%;
  overflow: hidden;
  min-height: 100vh;
  */



  /* 3.背景全屏缩放大小，内容完全显示且可滚动查看,绝对定位*/
  
  width: 100%;
  min-height: 100vh;
  background: url("../assets/bg.jpg") center center no-repeat;
  background-size: 100% 100%;
  position:absolute;



}

</style>