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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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About the <head>

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CSS

About CSS Preprocessors

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-.

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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

Add Packages

Search for and use JavaScript packages from npm here. By selecting a package, an import statement will be added to the top of the JavaScript editor for this package.

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HTML 

              
                <div class="gradient-box linear">
  <div class="linear-1">1</div>
  <div class="linear-2">2</div>
  <div class="linear-3">3</div>
  <div class="linear-4">4</div>
  <div class="linear-5">5</div>
  <div class="linear-6">6</div>
  <div class="linear-7">7</div>
  <div class="linear-8">8</div>
  <div class="linear-9">9</div>
  <div class="linear-10">10</div>
</div>
!

CSS 

              
                .gradient-box {
  display: flex;
  flex-wrap: wrap;
  div {
    width: 100px;
    height: 100px;
    align-content: center;
    text-align: center;
    font-weight: bold;
    color: #ffffff;
    font-size: 20px;
    display: inline-block;
  }
}

.linear-1 {
  /* orangeからblueにグラデする。orange 0%, blur 100% と同じ挙動 */
  background: linear-gradient(orange, blue);
}
.linear-2 {
  /* 左から右にグラデする。to right = 90deg or 0.25turn と同じ挙動 */
  background: linear-gradient(to right, orange, blue);
}
.linear-3 {
  /* 45度回転した状態でグラデする。45deg = to right top or 0.125turn と同じ挙動 */
  background: linear-gradient(45deg, orange, blue);
}
.linear-4 {
  /* グラデ軸の開始点を10%, 終了点を50%にする。 */
  background: linear-gradient(orange 10%, blue 50%);
}
.linear-5 {
  /* 複数グラデ&各色の開始を指定 */
  background: linear-gradient(orange 10%, blue 50%, deeppink 100%);
}
.linear-6 {
  /* グラデ軸の開始と終了点が同じのため変化が急になる。指定数値が昇順じゃない場合も開始＞終了となるので変化が急になる */
  background: linear-gradient(orange 30%, blue 30%);
}
.linear-7 {
  /* 変化の中心点を30%にする */
  background: linear-gradient(orange 0%, 30%, blue 100%);
}
.linear-8 {
  /* 左下に向かって複数グラデ */
  background: linear-gradient(to bottom right, orange 0% 20%, blue 20% 40%, deeppink 40% 60%, lime 60% 80%, yellow 80% 100%);
}
.linear-9 {
  /* 複数レイヤー(?)でのグラデ。透過箇所がない場合は最初に指定した色が表示される */
  background: linear-gradient(orange, transparent, transparent),
              linear-gradient(transparent, blue, transparent),
              linear-gradient(transparent, transparent, deeppink);
}
.linear-10 {
  /* 背景画像に対してのグラデ */
  background: linear-gradient(transparent, orange), url("https://i.imgur.com/djkvTYX.png") center no-repeat;
  background-size: contain;
}
!

JS
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999px

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