<style>body{ width:90%; margin:0 auto} #content{ overflow:auto; height:100%;} #nav,#feature,#footer{ background-color:#efefef; margin:1%;} .col1,.col2,.col3{ background-color:#efefef; width:31.3%px; float:left; margin:1%;} li{ display:inline; padding:0.5em;} #nav,#footer{ background-color:#efefef; padding:0.5em 0;} #feature,.article{ height:10em; margin-bottom:1em; background-color:#efefef;}</style>
<body><div id="header"><h1>Logo</h1><div id="nav"><ul><li>A</li><li>B</li><li>C</li><li>D</li><li>E</li></ul></div></div><div id="content"><div id="feature"><p>Feature</p></div><div class="article col1"><p>col one</p></div><div class="article col2"><p>col two</p></div><div class="article col3"><p>col three</p></div></div><div id="footer"><p>Copynight 2011</p></div></body>
.col1,.col2,.col3{ background-color:#efefef; width:31.3%px; float:left; margin:1%;}
<div class="article col1"><p>col one</p></div><div class="article col2"><p>col two</p></div><div class="article col3"><p>col three</p></div>
? え?違いは何ですか?
答えられる専門家はいますか