CSS预处理语言

CSS预处理语言

　　Less,Sass,Stylus

安装

Less

　　yarn add less

　　运行命令 ./node_modules/.bin/lessc

嵌套规则

Less、Sass嵌套规则一样

#header {
  h1 {
    font-size: 26px;
    font-weight: bold;
  }
  p { font-size: 12px;
    a { text-decoration: none;
      &:hover { border-width: 1px }
    }
  }
}

变量

Less

@color: #4D926F;

#header {
  color: @color;
}
h2 {
  color: @color;
}

Sass

$nav-color: #F90;
nav {
  $width: 100px;
  width: $width;
  color: $nav-color;
}

Less变量采用的是@

Sass变量采用的是$

混合(mixin)

Less

.rounded-corners (@radius: 5px) {
  border-radius: @radius;
  -webkit-border-radius: @radius;
  -moz-border-radius: @radius;
}

#header {
  .rounded-corners;
}
#footer {
  .rounded-corners(10px);
}

Sass

@mixin rounded-corners ($radius: 5px) {
  border-radius: $radius;
  -webkit-border-radius: $radius;
  -moz-border-radius: $radius;
}

#header {
  @include rounded-corners;
}
#footer {
  @include rounded-corners(10px);
}

Less的mixin尽可能的跟CSS一样

Sass的mixin接近JS的书写风格  @mixin  @include

extend

Less

.a{
    &:extend(.b);
    font-size: 12px;
}
.b{
    font-weight: bold;
}

Sass

.a{
    @extend .b;
    font-size: 12px;
}
.b{
    font-weight: bold;
}

Less和Sass书写区别