W3Schools Tryit Editor

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<h1>Change the grid-template-columns Property with JavaScript</h1>
<p>Click the button to change the grid layout from a four columns layout to a three columns layout, where each column is 50px wide:</p>
<p><button>Change layout</button></p>
<div id="myDIV">
 <div>1</div>
 <div>2</div>
 <div>3</div> 
 <div>4</div>
 <div>5</div>
 <div>6</div>
 <div>7</div>
 <div>8</div>
</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/cssref/tryit.php?filename=trycss_js_grid-template-columns">(->オリジナル)</a>
/ <label>アドレス: <input type="text" name="naked_post_url" value="http://www.w3schools.com/cssref/tryit.php?filename=trycss_js_grid-template-columns" 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>
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