Sass 3.4.13 发布，该版本改进记录：
Be clearer in the reference about hyphen/underscore equivalence.
@keyframes rules are now converted from CSS properly.
Extending a selector that contains a non-final pseudo-class no longer crashes.
When @extending, only a single :root element will be retained.
Sass 扩展了 CSS3，增加了规则、变量、混入、选择器、继承等等特性。Sass 生成良好格式化的 CSS 代码，易于组织和维护。
软件详情：http://sass-lang.com/
下载地址：https://github.com/sass/sass
来自:开源中国社区
