// 清除浮动
%clearfix {

    &:after,
    &:before {
      content: " ";
      display: table;
    }
  
    &:after {
      clear: both;
    }
  }
  
  // 文字溢出省略，仅webkit支持多
  @mixin ellipsis($lines) {
    @if ($lines==1) {
      overflow: hidden;
      text-overflow: ellipsis;
      white-space: nowrap;
    }
  
    @else {
      display: -webkit-box;
      -webkit-box-orient: vertical;
      -webkit-line-clamp: $lines;
      overflow: hidden;
      text-overflow: ellipsis;
      word-break: break-all;
    }
  }
  
  %ellipsis {
    @include ellipsis(1);
  }
  
  // 去掉滚动条
  %no-scrollbar {
    &::-webkit-scrollbar {
      display: none !important;
      width: 0 !important;
      height: 0 !important;
      -webkit-appearance: none;
      opacity: 0 !important;
    }
  }
  
  // 使用 @extend %no-scrollbar;
  
  // 一像素边框
  %_onepxElement {
    content: '';
    position: absolute;
  }
  
  %_onepxTopBottom {
    @extend %_onepxElement;
    left: 0;
    right: 0;
  }
  
  %_onepxLeftRight {
    @extend %_onepxElement;
    top: 0;
    bottom: 0;
  }
  
  @mixin setDprBorder($direction: tb) {
    @for $i from 1 through 4 {
      @media screen and (-webkit-min-device-pixel-ratio: $i) {
        @if($direction==tb) {
          transform: scaleY(1 / $i);
        }
  
        @else if($direction==lr) {
          transform: scaleX(1 / $i);
        }
  
        @else if($direction==full) {
          transform: scale(1 / $i);
        }
      }
    }
  }
  
  /*
   * 一像素边框
   * $direction: 边框方向，默认底边框
   * $style: 线条样式，默认solid
   * $color: 边框颜色
   */
  @mixin one-px-border($direction: bottom, $style: solid, $color: #e5e5e5) {
    position: relative;
    $border: 1px $style $color;
  
    @if ($direction==bottom) {
      &:after {
        @extend %_onepxTopBottom;
        @include setDprBorder(tb);
        border-top: $border;
        bottom: 0;
      }
    }
  
    @else if ($direction==top) {
      &:before {
        @extend %_onepxTopBottom;
        @include setDprBorder(tb);
        border-top: $border;
        top: 0;
      }
    }
  
    @else if ($direction==left) {
      &:before {
        @extend %_onepxLeftRight;
        @include setDprBorder(lr);
        border-left: $border;
        left: 0;
      }
    }
  
    @else if ($direction==right) {
      &:after {
        @extend %_onepxLeftRight;
        @include setDprBorder(lr);
        border-left: $border;
        right: 0;
      }
    }
  }
  
  // 默认下边框
  %one-px-border {
    @include one-px-border();
  }
  
  // 四边一像素边框
  @mixin full-px-border($color: #e5e5e5, $radius: 0, $zIndex: -1) {
    position: relative;
    z-index: 1;
  
    &:before {
      content: '';
      position: absolute;
      z-index: $zIndex;
      border: 1px solid $color;
      width: 200%;
      height: 200%;
      border-radius: inherit;
      transform: scale(.5);
      transform-origin: top left;
      border-radius: $radius * 2;
      left: 0;
      top: 0
    }
  }
  
  %full-px-border {
    @include full-px-border();
  }
  
  
  
  // 去除单位并返回数值
  @function strip-units($number) {
    @return $number / ($number * 0 + 1);
  }
  
  // px转rem
  @mixin px2rem($attr, $num, $base: 37.5) {
    $list: (); //存储所有转换后的值
  
    // 遍历所有值并转换为rem单位
    @for $i from 1 through length($num) {
      // 计算单个rem值
      $value: strip-units(nth($num, $i)) / $base * 1rem;
      // 添加到列表中
      $list: append($list, $value);
    }
  
    // 设置属性值
    #{$attr}:$list;
  }
  
  @function px2rem($num, $base: 37.5) {
    @return strip-units($num) / $base * 1rem;
  }
  
  // 居中一个元素
  @mixin center($position) {
    position: absolute;
  
    @if $position=='vertical' {
      top: 50%;
      transform: translateY(-50%);
    }
  
    @else if $position=='horizontal' {
      left: 50%;
      transform: translateX(-50%);
    }
  
    @else if $position=='both' {
      top: 50%;
      left: 50%;
      transform: translate(-50%, -50%);
    }
  }
  
  // 该函数可以用来做各种方向的背景渐变，
  @mixin background-gradient($start-color, $end-color, $orientation) {
    background: $start-color;
  
    @if $orientation=='vertical' {
      background: linear-gradient(to bottom, $start-color, $end-color);
    }
  
    @else if $orientation=='horizontal' {
      background: linear-gradient(to right, $start-color, $end-color);
    }
  
    @else {
      background: radial-gradient(ellipse at center, $start-color, $end-color);
    }
  }
  
  // 
  @mixin triangle($direction: down, $size: 5px, $color: #F96001) {
    width: 0px;
    height: 0px;
  
    @if ($direction==left) {
      border-top: $size solid transparent;
      border-bottom: $size solid transparent;
      border-right: $size solid $color;
    }
  
    @else if ($direction==right) {
      border-top: $size solid transparent;
      border-bottom: $size solid transparent;
      border-left: $size solid $color;
    }
  
    @else if ($direction==down) {
      border-left: $size solid transparent;
      border-right: $size solid transparent;
      border-top: $size solid $color;
    }
  
    @else {
      border-left: $size solid transparent;
      border-right: $size solid transparent;
      border-bottom: $size solid $color;
    }
  } 

//   媒体查询

$width-small: 400px;
$width-medium: 760px;
$width-large: 1200px;

@mixin responsive($width) {
  @if $width==wide-screens {
    @media only screen and (max-width: $width-large) {
      @content;
    }
  }

  @else if $width==medium-screens {
    @media only screen and (max-width: $width-medium) {
      @content;
    }
  }

  @else if $width==small-screens {
    @media only screen and (max-width: $width-small) {
      @content;
    }
  }
}

// @include responsive(wide-screens) {
//   width: 80%;
// }

// @include responsive(medium-screens) {
//   width: 50%;
//   font-size: 14px;
// }

// @include responsive(small-screens) {
//   float: none;
//   width: 100%;
//   font-size: 12px;
// }