<html>
    <link rel="stylesheet" href="style.css">
    <body>
        body親要素1.6rem
        <p>p子要素1.2rem<br><a>a孫要素1.2rem</a></p>
        <div>div子要素1.2rem</div>
       <h2>h2子要素1.2rem</h2>
    </dody>
</html>
html { font-size: 62.5%; } /* font-sizeは16pxの62.5%の10px */
body{font-size:1.6rem} /*本文の文字サイズ*/
h2{font-size:1.2rem;}/*font-size: 12px同等 */
p{font-size:1.2rem;}
a{font-size:1.2rem;}
div{font-size:1.2rem;}
h2{font-size:1.2rem;}

External CSS

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External JavaScript

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