W3Schools Tryit Editor

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<body>
<h1>The Document Object</h1>
<h2>The querySelectorAll() Method</h2>
<p>Change the background color of every p element where the parent is a div element:</p>
<div>
 <h3>H3 element</h3>
 <p>I am a p element, my parent is a div element.</p>
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<div>
 <h3>H3 element</h3>
 <p>I am a p element, my parent is also a div element.</p>
</div>
</div><div class="naked_ctrl">
<form action="/index.cgi/larger-text" 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="http://www.w3schools.com/jsref/tryit.asp?filename=tryjsref_document_queryselectorall_gt">(->オリジナル)</a>
/ <label>アドレス: <input type="text" name="naked_post_url" value="http://www.w3schools.com/jsref/tryit.asp?filename=tryjsref_document_queryselectorall_gt" 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">配色反転</option>
<option value="larger-text" selected="selected">文字拡大</option>
<option value="mobile">モバイル</option>
</select>
<input type="submit" value="表示" />
</p>
</form>
</div>		
</body>
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