css预处理器有 sass 、less
sass有两套语法: scss和sass,现在我们通常用sass
style.scss
.foo{
color: red;
font-size: 12px;
}
style.sass
.foo
color: red
font-size: 12px
安装sass
npm install -g sass
编译sass: 编译后sass转css
sass ./src/style.scss ./dist/index.css
以前的css写法:
.container {
max-width: 600px;
width: 100%;
margin: auto;
background: #eee;
}
.container .sidebar,
.container .main {
padding: 10px;
}
.container .marin {
margin-left: 220px;
min-height: 100vh;
border-left: 2px solid #333;
}
.container .sidebar {
width: 200px;
float: left;
}
现在的sass嵌套写法:
.container {
max-width: 600px;
width: 100%;
margin: auto;
background: #eee;
.sidebar,
.main {
padding: 10px;
}
.marin {
margin-left: 220px;
min-height: 100vh;
border-left: 2px solid #333;
}
.sidebar {
width: 200px;
float: left;
}
}
直接子元素:
.container {
>.left-area {
color: #444;
}
}
等于css:
.container > .left-area {
color: #444;
}
&父亲选择器:
.container {
&.right-nav {
color: #333;
}
}
div{
&.dome{
color: yellow;
}
a{
color: red;
}
}
等于css:
.container.right-nav {
color: #333;
}
div.dome {
color: yellow;
}
div a {
color: red;
}