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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.

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JavaScript

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Babel includes JSX processing.

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HTML 

              
                <body>
<h1>CSS:Position 範例</h1>

<div id="parent-container">
<strong>position:static (靜態定位)</strong><br>  
1. 該元素為此頁面中的父階層。此頁中其他的元素都是該元素的的子階層<br>
2. 該元素在 CSS 尚未設定 position 參數，就會被默認為「靜態定位（position:static）」，意即「不會被特別定位」在頁面上特定位置，而是照著瀏覽器預設的配置自動排版在頁面上。
  
<div id="static">
<strong>position:static (靜態定位)</strong><br> 1. 這元素被定位為「靜態定位（position:static）」，遵循「常態佈局」來排列。<br>所謂「常態佈局」就是「不會被特別定位」在頁面上特定位置，而是照著瀏覽器預設的配置自動排版在頁面上。
<br>
  2. 靜態定位的元素不受 top、bottom、left 與 right 屬性的影響。</div>
<div class="absolute">
<strong>position: absolute (絕對定位)-以網頁為定位點</strong><br> 
這個元素被設定成絕對定位（position: absolute;），當元素的 position 設定為 absolute 後，它就會看它的父層元素 position 是否有被設定為 relative、absolute 或是 fixed 的任一個，若有，則以父元素為定位基準點；若無，則以整個網頁頁面為基準定位。<br>
此例的父層元素 position 為 static，不屬於 relative、absolute、fixed 的任一個，因此會以整個網頁的頁面為定位基準：由最上方往下移動 200 px、由最右方往左移動 30 px。<br>
</div>
  
<div id="relative">
<strong>position: relative (相對定位)-尚未指定屬性</strong><br>此元素為「相對定位（position:relative）」的區塊，但因為沒有加入任何「left、right、bottom、top」屬性，所以表現得跟預設的「position:static」一樣。</div> 
  
<div id="relative-2"><strong>position: relative (相對定位)-已指定屬性</strong><br>這個元素是「相對定位（position:relative）」的區塊，已加入了「top: -20px;left: 20px;」的屬性，所以會相對於它「本來該出現的位置（指預設為）」進行定位:比原本在 static 的狀況時，向上偏移了 50px、並且離原本位置的最左側偏移了 20px。
  
<div class="absolute-2">
<strong>position: absolute (絕對定位)-以父元素為定位點</strong><br>
這裡又來一個 position 為「絕對定位（position: absolute）」的元素，會先看它的父層元素的 position 是否有被設定為 relative、absolute 或是 fixed，若有，則以父元素為定位基準。<br>
此例的父元素都有設定為 position:relative，因此以父元素為定位基準，往下移動 80 px、往左移動 30 px。<br>
</div>
  </div>    
<div id="fixed">
<strong>position: fixed (固定定位)</strong>
1. 該元素被設定為「固定定位（position:fixed）」，被固定在相對於瀏覽器視窗的最下方（bottom:0;margin: 0;）、最右方的位置（bottom: 0;right: 0;）<br>
2. 不屬於「Normal flow（常態佈局）」的其中一部分<br>
3. 位置相對於瀏覽器視窗來定位，這意味著即便頁面捲動，它還是會固定在相同的位置。
  </div>
</div>
</body>
!

CSS 

              
                h1{
text-align: center;
font-family: 'Noto Sans TC', sans-serif;
background: linear-gradient(45deg, red, blue);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

div {
  text-align: left;
  border: 5px solid magenta;
  font-weight: 600px;
  font-size: 16px;
  box-sizing: border-box;
  padding: 4px;
}

#static {
  border: 5px solid teal;
  height: ;
  width: 300px;
  text-align: left;
}
#relative {
  border-color: orange;
  position: relative;
  width:500px;
}
#relative-2 {
  border-color: orange;
  position: relative;
  top: -20px;
  left: 20px;
  height: 200px;
  background-color: white;
}
#fixed {
  text-align: left;
  border: none;
  position: fixed;
  bottom: 0;
  right: 0;
  margin: 0;
  width: 500px;
  background-color: black;
  color: white;
}
.absolute {
  text-align: left;
  border-color: red;
  position: absolute;
  top: 200px;
  right: 30px;
  max-width: 75%;
  background-color: #f2f2f2;
  box-shadow: 6px 6px rgba(0, 0, 0, 0.3)
}
.absolute-2 {
  text-align: left;
  border-color: red;
  position: absolute;
  top: 80px;
  right: 30px;
  max-width: 80%;
  background-color: #f2f2f2;
  box-shadow: 6px 6px rgba(0, 0, 0, 0.3)
}
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JS
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999px

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