成功应用背景图像的步骤

确保使用link标签正确链接了HTML和CSS <link rel="stylesheet" ref="yourcssdocument.css"> 我不知道相对目录和子目录，所以我不能评论它 对我来说，最好的方法是在css中使用URL链接

#yourcssdoc .image {
   background-image: url("paste your link here with the quotations")
}

在CSS的.content选项卡中将其更改为position:absolute。否则，渲染的页面将不可滚动。

pen

取消了对额外元素的需求，同时使内容适合文档流，而不是像其他解决方案那样固定/绝对。

通过使用

.content { /* this is needed or the background will be offset by a few pixels at the top */ overflow: auto; position: relative; } .content::before { content: ""; position: fixed; left: 0; right: 0; z-index: -1; display: block; background-image: url('https://i.imgur.com/lL6tQfy.png'); background-size:cover; width: 100%; height: 100%; -webkit-filter: blur(5px); -moz-filter: blur(5px); -o-filter: blur(5px); -ms-filter: blur(5px); filter: blur(5px); } <div class="content"> Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum. </div>

编辑如果你想删除边缘的白色边框，使用宽度和高度为110%，左侧和顶部为-5%。这将放大你的背景-但不应该有纯色从边缘流出。感谢Chad Fawcett的建议。

.content { /* this is needed or the background will be offset by a few pixels at the top */ overflow: auto; position: relative; } .content::before { content: ""; position: fixed; top: -5%; left: -5%; right: -5%; z-index: -1; display: block; background-image: url('https://i.imgur.com/lL6tQfy.png'); background-size:cover; width: 110%; height: 110%; -webkit-filter: blur(5px); -moz-filter: blur(5px); -o-filter: blur(5px); -ms-filter: blur(5px); filter: blur(5px); } <div class="content"> Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum. </div>

规范引入了一个新的filter()函数，你可以像下面这样使用背景图像:

background: filter(url("whatever.jpg"), blur(5px));

<filter()>函数有两个参数。第一个参数是<image>。第二个是为CSS filter属性指定的筛选器函数列表。该函数接受参数并应用筛选规则，返回一个处理图像。

但是浏览器不支持这个:https://caniuse.com/css-filter-function。目前只能在Safari上进行测试。

这个答案是为材料设计水平卡片布局动态高度和图像。

为了防止由于卡片的动态高度而导致图像失真，您可以使用带有模糊的背景占位符图像来调整高度的变化。

解释

The card is contained in a <div> with class wrapper, which is a flexbox. The card is made up of two elements, an image which is also a link, and content. The link <a>, class link, is positioned relative. The link consists of two sub-elements, a placeholder <div> class blur and an <img> class pic which is the clear image. Both are positioned absolute and have width: 100%, but class pic has a higher stack order, i.e., z-index: 2, which places it above the placeholder. The background image for the blurred placeholder is set via inline style in the HTML.

Code

.wrapper { display: flex; width: 100%; border: 1px solid rgba(0, 0, 0, 0.16); box-shadow: 0 1px 1px rgba(0, 0, 0, 0.16), 0 1px 1px rgba(0, 0, 0, 0.23); background-color: #fff; margin: 1rem auto; height: auto; } .wrapper:hover { box-shadow: 0 3px 6px rgba(0, 0, 0, 0.16), 0 3px 6px rgba(0, 0, 0, 0.23); } .link { display: block; width: 200px; height: auto; overflow: hidden; position: relative; border-right: 2px solid #ddd; } .blur { position: absolute; top: 0; left: 0; right: 0; bottom: 0; margin: auto; width: 100%; height: 100%; filter: blur(5px); -webkit-filter: blur(5px); -moz-filter: blur(5px); -o-filter: blur(5px); -ms-filter: blur(5px); } .pic { width: calc(100% - 20px); max-width: 100%; height: auto; margin: auto; position: absolute; top: 0; left: 0; right: 0; bottom: 0; z-index: 2; } .pic:hover { transition: all 0.2s ease-out; transform: scale(1.1); text-decoration: none; border: none; } .content { display: flex; flex-direction: column; width: 100%; max-width: 100%; padding: 20px; overflow-x: hidden; } .text { margin: 0; } <div class="wrapper"> <a href="#" class="link"> <div class="blur" style="background: url('https://i.imgur.com/5SZI6qZ.jpeg') 50% 50% / cover;"></div> <img src="https://i.imgur.com/5SZI6qZ.jpeg" alt="Title" class="pic" /> </a> <div class="content"> <p class="text">Agendum dicendo memores du gi ad. Perciperem occasionem ei ac im ac designabam. Ista rom sibi vul apud tam. Notaverim to extendere expendere concilium ab. Aliae cogor tales fas modus parum sap nullo. Voluntate ingressus infirmari ex mentemque ac manifeste eo. Ac gnum ei utor sive se. Nec curant contra seriem amisit res gaudet adsunt. </p> </div> </div>

下面是一个简单的解决方案，适用于现代浏览器，使用纯CSS和一个'before'伪元素，就像Matthew Wilcoxson的解决方案一样。

为了避免在JavaScript中需要访问伪元素来更改图像和其他属性，只需使用inherit作为值，并通过父元素(这里是body)访问它们。

body::before {
    content: ""; /* Important */
    z-index: -1; /* Important */
    position: inherit;
    left: inherit;
    top: inherit;
    width: inherit;
    height: inherit;
    background-image: inherit;
    background-size: cover;
    filter: blur(8px);
}

body {
  background-image: url("xyz.jpg");
  background-size: 0 0;  /* Image should not be drawn here */
  width: 100%;
  height: 100%;
  position: fixed; /* Or absolute for scrollable backgrounds */
}