Question

我正在尝试在背景图片上叠加CSS渐变。我已经在Firefox中使用了它，但在safari和chrome中我只获得了背景图像，没有渐变。

（我使用http://www.colorzilla.com/gradient-editor/生成了渐变代码，然后在每行的末尾添加了url（））

更新：似乎我的问题可能是webkit显示图像背后的渐变，而不是像我需要的那样，而firefox就是这样。

  background: -moz-linear-gradient(top, rgba(0, 0, 0, 0) 0%, rgba(99, 130, 169, 0.7) 100%), url(app/bg.jpg) no-repeat center center fixed; /* FF3.6+ */
  background: -webkit-gradient(linear, left top, left bottom, color-stop(0%,rgba(0, 0, 0, 0)), color-stop(100%, rgba(99, 130, 169, 0.7))), url(app/bg.jpg) no-repeat center center fixed; /* Chrome,Safari4+ */
  background: -webkit-linear-gradient(top, rgba(0, 0, 0, 0) 0%,rgba(0,0,0,0.16) 100%), url(app/bg.jpg) no-repeat center center fixed; /* Chrome10+,Safari5.1+ */
  background: -o-linear-gradient(top, rgba(0, 0, 0, 0) 0%,rgba(99, 130, 169, 0.7) 100%), url(app/bg.jpg) no-repeat center center fixed; /* Opera 11.10+ */
  background: -ms-linear-gradient(top, rgba(0, 0, 0, 0) 0%,rgba(99, 130, 169, 0.7) 100%), url(app/bg.jpg) no-repeat center center fixed; /* IE10+ */
  background: linear-gradient(to bottom, rgba(0, 0, 0, 0) 0%,rgba(99, 130, 169, 0.7) 100%), url(app/bg.jpg) no-repeat center center fixed; /* W3C */

Answer 1

我建议在这种情况下使用速记符号，这将使其更容易阅读和维护（并解决了问题）。这是一个工作示例（和演示：http://jsfiddle.net/joshnh/yyy7V/）：

.foo {
    background-image: -webkit-gradient(linear, left top, left bottom, color-stop(0%, rgba(0, 0, 0, 0)), color-stop(100%, rgba(99, 130, 169, 0.7))), url('http://lorempixel.com/400/300/'); /* Chrome,Safari4+ */
    background-image: -webkit-linear-gradient(top, transparent, rgba(99,130,169,.7)), url('http://lorempixel.com/400/300/'); /* Chrome10+,Safari5.1+ */
    background-image:    -moz-linear-gradient(top, transparent, rgba(99,130,169,.7)), url('http://lorempixel.com/400/300/'); /* FF3.6+ */
    background-image:     -ms-linear-gradient(top, transparent, rgba(99,130,169,.7)), url('http://lorempixel.com/400/300/'); /* IE10+ */
    background-image:      -o-linear-gradient(top, transparent, rgba(99,130,169,.7)), url('http://lorempixel.com/400/300/'); /* Opera 11.10+ */
    background-image:         linear-gradient(to bottom, transparent, rgba(99,130,169,0.7)), url('http://lorempixel.com/400/300/'); /* W3C */

    background-repeat: no-repeat;
    background-position: 50% 50%;
    background-attachment: fixed;
}

Answer 2

图像落后于WebKit中的渐变。只是WebKit代码使用了另一种颜色rgba(0,0,0,0.16)，其中比用于其他浏览器{/ 1}}的颜色更难以发现。

Answer 3

我认为这里的问题来自CSS的排序。 Try Chris Coyier's appraoch instead.

.gradient-bg {
   background-color: #1a82f7; 
   background-image: url(images/fallback-gradient.png); 
   background-image: -webkit-gradient(linear, 0% 0%, 0% 100%, from(#2F2727), to(#1a82f7));
   background-image: -webkit-linear-gradient(top, #2F2727, #1a82f7); 
   background-image:    -moz-linear-gradient(top, #2F2727, #1a82f7);
   background-image:     -ms-linear-gradient(top, #2F2727, #1a82f7);
   background-image:      -o-linear-gradient(top, #2F2727, #1a82f7);
}

具有渐变叠加的CSS3背景 - 渐变仅在Firefox中工作

3 个答案: