我有一个JPEG文件，我使用作为搜索页面的背景图像，我使用CSS来设置它，因为我在Backbone.js上下文中工作:
background-image: url("whatever.jpg");
我想应用css3模糊过滤器只对背景，但我不确定如何样式只是一个元素。如果我试着:
-webkit-filter: blur(5px);
-moz-filter: blur(5px);
-o-filter: blur(5px);
-ms-filter: blur(5px);
filter: blur(5px);
就在我的CSS中的background-image下面，它为整个页面设置了样式，而不仅仅是背景。是否有一种方法只选择图像并应用过滤器?或者，有没有一种方法可以关闭页面上所有其他元素的模糊效果?
当前回答
CSS网格对我来说更容易理解。：）
html, body { width: 100%; height: 100%; } .container { width: 100%; height: 100%; display: grid; grid-template-columns: 1fr 6fr 1fr; grid-template-rows: 1fr 6fr 1fr; grid-template-areas: '. . .' '. content .' '. . .'; justify-content: center; align-items: center; } .backbround { width: 100%; height: 100%; grid-area: 1/1/5/5; background-image: url(https://i.imgur.com/aUhpEz3.jpg); filter: blur(5px); background-position: center; background-repeat: no-repeat; background-size: cover; } .content { height: 200px; position: relative; grid-area: content; display: flex; justify-content: center; align-items: center; color: white; } <div class="container"> <div class="backbround"></div> <div class="content"><h1>Hello World</h1></div> </div>
其他回答
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 */
}
我没有写这个，但是我注意到使用CSS SASS编译器有一个部分支持的后台过滤器的polyfill，所以如果你有一个编译管道，它可以很好地实现(它也使用TypeScript):
https://codepen.io/mixal_bl4/pen/EwPMWo
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>
为此，您需要重新构造HTML。为了模糊背景，你必须模糊整个元素。如果你只想模糊背景，它必须是它自己的元素。
<!-- Q:Create the blur on parenttal div without effecting the child div -->
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
</head>
<style>
*{
margin: 0; padding: 0; box-sizing: border-box;
font-size: 30px;
}
.parent{
background-image:url(hobby.jpg) ;
height: 100vh;
width: 100vw;
background-repeat: no-repeat;
background-size: cover;
background-position: center;
display: flex;
justify-content: center;
align-items: center;
}
.child{
height: 90vh;
width: 90vw;
backdrop-filter: blur(10px);
border: 1px solid rgba(0, 0, 0, 0.418);
justify-content: center;
align-items: center;
display: flex;
}
.text{
height: 300px;
width: 300px;
border-radius: 500px;
background-image: url(50cf380e5c78eb174faa8e6ac2cb654a.jpg);
background-size: cover;
background-position: center;
}
</style>
<body>
<div class="parent">
<div class="child">
<div class="text"></div>
</div>
</div>
</body>
</html>
