W3Schools Tryit Editor

<!doctype html>
<html>

<body>
<h1>Smooth Scroll</h1>
<div id="section1">
 <h2>Section 1</h2>
 <p>Click on the link to see the "smooth" scrolling effect.</p>
 <a href="#section2">Click Me to Smooth Scroll to Section 2 Below</a>
 <p>Note: Remove the scroll-behavior property to remove smooth scrolling.</p>
</div>
<div id="section2">
 <h2>Section 2</h2>
 <a href="#section1">Click Me to Smooth Scroll to Section 1 Above</a>
</div>
</div><div class="naked_ctrl">
<form action="/index.cgi/contrast" method="get" name="gate">
<p><a href="http://altstyle.alfasado.net">AltStyle</a> によって変換されたページ <a href="https://www.w3schools.com/cssref/tryit.php?filename=trycss_scroll_behavior">(->オリジナル)</a>
/ <label>アドレス: <input type="text" name="naked_post_url" value="https://www.w3schools.com/cssref/tryit.php?filename=trycss_scroll_behavior" size="22" /></label> <label>モード: <select name="naked_post_mode">
<option value="default">デフォルト</option>
<option value="speech">音声ブラウザ</option>
<option value="ruby">ルビ付き</option>
<option value="contrast" selected="selected">配色反転</option>
<option value="larger-text">文字拡大</option>
<option value="mobile">モバイル</option>
</select>
<input type="submit" value="表示" />
</p>
</form>
</div>		
</body>
</html>