在 CSS 中根据浏览器大小更改背景颜色

Question

我不知道这段代码有什么问题。背景颜色根本没有改变，它一直保持白色。

<style type="text/css">
      h1 {
        position: absolute;
        text-align: center;
        width: 100%;
        font-size: 6em;
        font-family: Roboto;
        transition: all 0.5s;
      }

      @media screen and (min-width: 0px) and (max-width: 400px) {
        background-color: red;
      }
      @media screen and (min-width: 401px) and (max-width: 599px) {
        background-color: green;
      }
      @media screen and (min-width: 600px) {
        background-color: blue;
      }
    </style>

Answer 1

尝试：

@media screen and (min-width: 0px) and (max-width: 400px) {
    body { background-color: red; }
}
@media screen and (min-width: 401px) and (max-width: 599px) {
    body { background-color: green; }
}
@media screen and (min-width: 600px) {
    body { background-color: blue; }
}

background-color 属性现在分配给 body

Answer 2

您需要为 media query 中的某些元素定义 CSS（例如本例中的 body）。这是一个demo.

试试这个：

h1 {
    position: absolute;
    text-align: center;
    width: 100%;
    font-size: 6em;
    font-family: Roboto;
    transition: all 0.5s;
  }

  @media screen and (min-width: 0px) and (max-width: 400px) {
    body{
      background-color: red;
    }
  }
  @media screen and (min-width: 401px) and (max-width: 599px) {
    body{
      background-color: green;
    }
  }
  @media screen and (min-width: 600px) {
    body{
      background-color: blue;
    }
  }

Answer 3

 @media screen and (min-width: 0px) and (max-width: 400px) {
   body{ background-color: red; }
 }
 @media screen and (min-width: 401px) and (max-width: 599px) {
   body{ background-color: green; }
 }
 @media screen and (min-width: 600px) {
   body{ background-color: blue; }
 }

样式仅适用于正文或任何class仅

Answer 4

h1 {
  position: absolute;
  text-align: center;
  width: 100%;
  transition: all 0.5s;
}

@media screen and (min-width: 0px) and (max-width: 400px) {
  body{
    background-color: red;
  }
}

@media screen and (min-width: 401px) and (max-width: 599px) {
  body{
    background-color: green;
  }
}
  
@media screen and (min-width: 600px) {
  body{
    background-color: blue;
  }
}

在 CSS 中根据浏览器大小更改背景颜色

Changing background color based on browser size in CSS

html

css

background-color

media-queries