生成一个指定选择器时，创建一个子选择器？
@import "compass/utilities/sprites";
@import "logo/*.png";
.test {
@include logo-sprites(icon-01);
}
生成的文件
/* line 64, logo/*.png */
.logo-sprite, .test .logo-icon-01 {
background-image: url('/Images/logo-s0130b10ba6.png');
background-repeat: no-repeat;
}
/* line 84, C:/Ruby22/lib/ruby/gems/2.2.0/gems/compass-core-1.0.3/stylesheets/compass/utilities/sprites/_base.scss */
.test .logo-icon-01 {
background-position: 0 0;
}
