如何在背景图片上应用CSS滤镜

Question

我有一个JPEG文件，我正在将其用作搜索页面的背景图像，并且我正在使用CSS进行设置，因为我在Backbone.js上下文中工作：background-image:url("whatever.jpg");我想仅将CSS3模糊滤镜应用于背景，但我不确定如何仅对该元素进行样式设置。如果我尝试：-webkit-filter:blur(5px);-moz-filter:blur(5px

P粉976737101 · Answer

pen

消除了额外元素的需要，并使内容适应文档流，而不像其他解决方案那样固定/绝对。

使用以下方式实现：

.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);
}


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.

编辑如果您希望删除边缘的白色边框，请使用110%的宽度和高度以及-5%的左边和顶部。这将稍微放大您的背景 - 但边缘不应有实心颜色渗入。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);
}


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.

P粉823268006 · Answer

查看这个pen。

你需要使用两个不同的容器，一个用于背景图片，另一个用于内容。

在示例中，我创建了两个容器，.background-image和.content。

它们都使用position: fixed和left: 0; right: 0;进行定位。它们显示的差异来自于为元素设置的不同z-index值。

.background-image {
  position: fixed;
  left: 0;
  right: 0;
  z-index: 1;
  display: block;
  background-image: url('https://i.imgur.com/lL6tQfy.png');
  width: 1200px;
  height: 800px;
  -webkit-filter: blur(5px);
  -moz-filter: blur(5px);
  -o-filter: blur(5px);
  -ms-filter: blur(5px);
  filter: blur(5px);
}

.content {
  position: fixed;
  left: 0;
  right: 0;
  z-index: 9999;
  margin-left: 20px;
  margin-right: 20px;
}



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