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HTML

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HTML preprocessors can make writing HTML more powerful or convenient. For instance, Markdown is designed to be easier to write and read for text documents and you could write a loop in Pug.

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Adding Classes

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CSS

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CSS preprocessors help make authoring CSS easier. All of them offer things like variables and mixins to provide convenient abstractions.

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CSS Base

About CSS Base

It's a common practice to apply CSS to a page that styles elements such that they are consistent across all browsers. We offer two of the most popular choices: normalize.css and a reset. Or, choose Neither and nothing will be applied.

Vendor Prefixing

About Vendor Prefixing

To get the best cross-browser support, it is a common practice to apply vendor prefixes to CSS properties and values that require them to work. For instance -webkit- or -moz-.

We offer two popular choices: Autoprefixer (which processes your CSS server-side) and -prefix-free (which applies prefixes via a script, client-side).

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JavaScript

About JavaScript Preprocessors

JavaScript preprocessors can help make authoring JavaScript easier and more convenient.

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Babel includes JSX processing.

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Packages

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HTML 

              
                .container
  h1.title Polygons
  ul.list
    li.lists--odd
      h2 5
      .pentagon
        - var i = 5;
        while i--
          div.rect
    li.lists
      h2 6
      .hexagon
        - var i = 3;
        while i--
          div.rect
    li.lists
      h2 8
      .octagon
        - var i = 4;
        while i--
          div.rect
    li.lists--odd
      h2 9
      .nonagon
        - var i = 9;
        while i--
          div.rect
    li.lists
      h2 10
      .decagon
        - var i = 5;
        while i--
          div.rect
    li.lists
      h2 12
      .dodecagon
        - var i = 6;
        while i--
          div.rect
    li.lists--odd
      h2 15
      .pentadecagon
        - var i = 15;
        while i--
          div.rect
    li.lists
      h2 16
      .hexadecagon
        - var i = 8;
        while i--
          div.rect
    li.lists
      h2 18
      .octadecagon
        - var i = 9;
        while i--
          div.rect
    li.lists
      h2 20
      .icosagon
        - var i = 10;
        while i--
          div.rect
!

CSS 

              
                @import url(https://fonts.googleapis.com/css?family=Quattrocento+Sans);

$size: 200px;
$bk-color: #f5f5f5;
$border-color: #333;
$rect-even-color: #333;
$rect-odd-color: transparent;
$text-even-color: #fff;
$text-odd-color: #000;

@mixin center {
  position: absolute;
  top: 0;
  bottom: 0;
  left: 0;
  right: 0;
  margin: auto;
}

@mixin center-tf {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%,-50%);
}

@mixin border {
  box-sizing: border-box;
  border: 1px solid $border-color;
  border-left: none;
  border-right: none;
}

body {
  width: 100%;
  height: 100%;
  background: $bk-color;
}

.container {
  position: relative;
  width: 100%;
  height: 100%;
  min-height: 100vh;
  margin: 0 auto;
  .title {
    position: relative;
    box-sizing: border-box;
    width: 200px;
    height: 40px;
    line-height: 40px;
    margin: 40px auto 0;
    padding-left: 10px;
    font-size: 11px;
    text-transform: uppercase;
    text-align: center;
    letter-spacing: 10px;
    font-family: 'Quattrocento Sans';
    &:before,
    &:after {
      content: '';
      position: absolute;
      top: calc(50% - 1px);
      width: 10px;
      height: 1px;
      background: #333;
    }
    &:before {
      left: 0;
    }
    &:after {
      right: 0;
    }
  }
}

.list {
  text-align: center;
}

.lists,
.lists--odd {
  position: relative;
  display: inline-block;
  width: 10%;
  min-width: $size * 1.5;
  height: $size * 1.5;
  h2 {
    font-size: 12px;
    color: $text-even-color;
    font-family: 'Quattrocento Sans';
    z-index: 1;
    @include center-tf;
  }
}

.lists--odd {
  h2 {
    color: $text-odd-color;
  }
}

.pentagon,
.hexagon,
.dodecagon,
.octagon,
.nonagon,
.decagon,
.pentadecagon,
.hexadecagon,
.octadecagon,
.icosagon {
  width: $size;
  height: $size;
  @include center;
  .rect {
    background: $rect-even-color;
    transform-origin: center center;
    @include border;
    @include center;
  }
}

.lists--odd {
  .rect {
    background: $rect-odd-color;
  }
}

.pentagon {
  .rect {
    width: 72.65425280053%;// √(5-2√5)
    height: 100%;
    border-top: none;
    @for $i from 0 through 4 {
      &:nth-of-type(#{$i + 1}) {
        transform: rotate(72deg * $i);
      }
    }
  }
}

.hexagon {
  .rect {
    width: 57.735026919%;// (50/√3)*2
    height: 100%;
    @for $i from 0 through 2 {
      &:nth-of-type(#{$i + 1}) {
        transform: rotate(60deg * $i);
      }
    }
  }
}

.octagon {
  .rect {
    width: 41.421356237%;// √2-1
    height: 100%;
    @for $i from 0 through 3 {
      &:nth-of-type(#{$i + 1}) {
        transform: rotate(45deg * $i);
      }
    }
  }
}

.nonagon {
  .rect {
    width: 36.397023426%;// tan(π/9)
    height: 100%;
    border-top: none;
    @for $i from 0 through 8 {
      &:nth-of-type(#{$i + 1}) {
        transform: rotate(40deg * $i);
      }
    }
  }
}

.decagon {
  .rect {
    width: 32.491969623%;// √(25-10√5)/5
    height: 100%;
    @for $i from 0 through 4 {
      &:nth-of-type(#{$i + 1}) {
        transform: rotate(36deg * $i);
      }
    }
  }
}

.dodecagon {
  .rect {
    width: 26.794919243%;// 2-√3 円に外接する正多角形
    height: 100%;
    @for $i from 0 through 5 {
      &:nth-of-type(#{$i + 1}) {
        transform: rotate(30deg * $i);
      }
    }
  }
}

.pentadecagon {
  .rect {
    width: 21.255656167%;// (-√(50-22√5)-√15+3√3)/2
    height: 100%;
    border-top: none;
    @for $i from 0 through 14 {
      &:nth-of-type(#{$i + 1}) {
        transform: rotate(24deg * $i);
      }
    }
  }
}

.hexadecagon {
  .rect {
    width: 19.891236738%;// tan(π/16)
    height: 100%;
    @for $i from 0 through 7 {
      &:nth-of-type(#{$i + 1}) {
        transform: rotate(22.5deg * $i);
      }
    }
  }
}

.octadecagon {
  .rect {
    width: 17.63269807%;// tan(π/18)
    height: 100%;
    @for $i from 0 through 8 {
      &:nth-of-type(#{$i + 1}) {
        transform: rotate(20deg * $i);
      }
    }
  }
}

.icosagon {
  .rect {
    width: 15.838444032%;// -√(5+2√5)+√5+1
    height: 100%;
    @for $i from 0 through 9 {
      &:nth-of-type(#{$i + 1}) {
        transform: rotate(18deg * $i);
      }
    }
  }
}
!

JS
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