Sass @mixin 与 @include

@mixin 指令允许我们定义一个可以在整个样式表中重复使用的样式。
@include 指令可以将混入（mixin）引入到文档中。

@mixin flex {
  display: flex;
}
@mixin flex-center-v {
  display: flex;
  align-items: center;
}
@mixin flex-center-h {
  display: flex;
  justify-content: center;
}
@mixin flex-center {
  display: flex;
  align-items: center;
  justify-content: center;
}
@mixin flex-column {
  display: flex;
  flex-flow: column wrap;
  align-items: center;
  justify-content: center;
}
@mixin ellipsis($lines) {
  overflow: hidden;
  text-overflow: ellipsis;
  display: -webkit-box;
  -webkit-line-clamp: $lines;
  -webkit-box-orient: vertical;
}
@mixin scroller {
  &::-webkit-scrollbar {
    background: transparent;
    width: 8px;
  }
  &::-webkit-scrollbar-thumb {
    background: #ddd;
  }
}

$purple: #d08fff;
$green: #43ac8d;
$primary: #ef7f45;
$primary-dark: #eb6528;
$blue: #1b9ef0;
$red: #ff3b45;

@import "./variables.scss";
@import "./mixins.scss";
#app {
  font-family: Avenir, Helvetica, Arial, sans-serif;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  color: #2c3e50;
  a {
    color: #42b983;
  }
}
.column-center {
  display: flex;
  flex-flow: column wrap;
  align-items: center;
}
.flex {
  @include flex;
}
.flex-center {
  @include flex-center;
}
.flex-center-v {
  @include flex-center-v;
}
.flex-center-h {
  @include flex-center-h;
}