css3 – 如何使跨浏览器渐变mixin在罗盘,与IE9,IE8,IE7和Opera？

我想为所有浏览器,包括IE9 IE9,IE8,IE7和Opera进行mixin.

像http://www.colorzilla.com/gradient-editor/生成代码

它产生

BACkground: #1e5799; /* Old browsers */
/* IE9 SVG,needs conditional override of 'filter' to 'none' */
BACkground: url(data:image/svg+xml;base64,PD94bWwgdmVyc2lvbj0iMS4wIiA/Pgo8c3ZnIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8ymDAwL3N2ZyIgd2lkdGg9ijewMCUiIGhlaWdodD0iMTAwJSIgdmlld0JveD0iMCAwIDEgMSIgcHJlc2VydmVBc3BlY3RSYXRpbz0ibm9uZSI+CiAgPGxpbmVhckdyYWRpZW50IGlkPSJncmFkLXVjZ2ctZ2VuZXJhdGVkIiBncmFkaWVudFVuaXRzPSJ1c2VyU3BhY2VPblVzZSIgeDE9ijAlIiB5MT0iMCUiIHgyPSIwJSIgeTI9ijewMCUiPgogICAgPHN0b3Agb2Zmc2V0PSIwJSIgc3RvcC1jb2xvcj0iIzFlNTc5OSIgc3RvcC1vcGFjaXR5PSIxIi8+CiAgICA8c3RvcCBvZmZzZXQ9ijUwJSIgc3RvcC1jb2xvcj0iIzI5ODlkOCIgc3RvcC1vcGFjaXR5PSIxIi8+CiAgICA8c3RvcCBvZmZzZXQ9ijUxJSIgc3RvcC1jb2xvcj0iIzIwN2NjYSIgc3RvcC1vcGFjaXR5PSIxIi8+CiAgICA8c3RvcCBvZmZzZXQ9ijewMCUiIHN0b3AtY29sb3I9iiM3ZGI5ZTgiIHN0b3Atb3BhY2l0eT0iMSIvPgogIDwvbGluZWFyR3JhZGllbnQ+CiAgPHJlY3QgeD0iMCIgeT0iMCIgd2lkdGg9ijeiIGhlaWdodD0iMSIgZmlsbD0idXJsKCNncmFkLXVjZ2ctZ2VuZXJhdGVkKSIgLz4KPC9zdmc+);
BACkground: -moz-linear-gradient(top,#1e5799 0%,#2989d8 50%,#207cca 51%,#7db9e8 100%); /* FF3.6+ */
BACkground: -webkit-gradient(linear,left top,left bottom,color-stop(0%,#1e5799),color-stop(50%,#2989d8),color-stop(51%,#207cca),color-stop(100%,#7db9e8)); /* Chrome,Safari4+ */
BACkground: -webkit-linear-gradient(top,#7db9e8 100%); /* Chrome10+,Safari5.1+ */
BACkground: -o-linear-gradient(top,#7db9e8 100%); /* Opera 11.10+ */
BACkground: -ms-linear-gradient(top,#7db9e8 100%); /* IE10+ */
BACkground: linear-gradient(top,#7db9e8 100%); /* W3C */
filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#1e5799',endColorstr='#7db9e8',GradientType=0 ); /* IE6-8 */

而对于IE9,我们需要设置filter：none

Compass具有渐变http://compass-style.org/reference/compass/css3/images/的最新模块,我们可以在调用$experimental-support-for-svg：true之后使用,例如使用像

.gradient {@include linear-gradient(#000000,#ff0000)}

这给出了这样的输出

.gradient {
  BACkground-image: url('data:image/svg+xml;base64,PD94bWwgdmVyc2lvbj0iMS4wIiBlbmNvZGluZz0idXRmLTgiPz4gPHN2ZyB2ZXJzaW9uPSIxLjeiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8ymDAwL3N2ZyI+PGRlZnM+PGxpbmVhckdyYWRpZW50IGlkPSJncmFkIiBncmFkaWVudFVuaXRzPSJ1c2VyU3BhY2VPblVzZSIgeDE9ijUwJSIgeTE9ijAlIiB4Mj0iNTAlIiB5Mj0iMTAwJSI+PHN0b3Agb2Zmc2V0PSIwJSIgc3RvcC1jb2xvcj0iIzAwMDAwMCIvPjxzdG9wIG9mZNNLdD0iMTAwJSIgc3RvcC1jb2xvcj0iI2ZmMDAwMCIvPjwvbGluZWFyR3JhZGllbnQ+PC9kZWZzPjxyZWN0IHg9ijAiIHk9ijAiIHdpZHRoPSIxMDAlIiBoZWlnaHQ9ijewMCUiIGZpbGw9inVybCgjZ3JhZCkiIC8+PC9zdmc+IA==');
  BACkground-size: 100%;
  BACkground-image: -webkit-gradient(linear,50% 0%,50% 100%,#000000),#ff0000));
  BACkground-image: -webkit-linear-gradient(#000000,#ff0000);
  BACkground-image: -moz-linear-gradient(#000000,#ff0000);
  BACkground-image: -o-linear-gradient(#000000,#ff0000);
  BACkground-image: -ms-linear-gradient(#000000,#ff0000);
  BACkground-image: linear-gradient(#000000,#ff0000);
}

如果我们比较compass Image代码这个colorzilla代码

>它的缺失是IE6-8

filter：progid：DXImageTransform.Microsoft.gradient(startColorstr =’#1e5799′,endColorstr =’#7db9e8′,GradientType = 0); / *
IE6-8 * /
>和旧版浏览器背景：#1e5799; / *旧浏览器* /
>而是使用BACkground-image代替BACkground
>它有一个额外的属性BACkground-size：100％;
>并且此页面上没有指令
http://compass-style.org/reference/compass/css3/images/为了如何
解决过滤器：IE9不需要.

我的问题：

>背景大小有什么好处：100％？
>使用背景图像而不是背景有什么好处？
>有没有办法添加过滤器：没有为元素仅为IE9的
罗盘？
>如何在这样的过滤器的指南针中获得IE6-8兼容代码：
progid：DXImageTransform.Microsoft.gradient(startColorstr =’#1e5799′,
endColorstr =’#7db9e8′,GradientType = 0);？