我是 html 和 css 的新手,如何使背景全尺寸?我假设它会在css中?
body {
  background: url(../images/bg.jpg) no-repeat;
}
    尝试这个:
body {
  background: url(../images/bg.jpg) no-repeat;
  -webkit-background-size: cover; /*-- Used for Chrome and Safari browsers --*/
  -moz-background-size: cover; /*-- Used for Firefox browser --*/
  -o-background-size: cover; /*-- Used for Opera browser --*/
  background-size: cover; /*-- Used for IE browser --*/
}