Generate roughly the given appearance, starting from this HTML and CSS code.
<div id="container"> <div id="header"> <h1>Header</h1> </div> <div id="left-column"> <h2>Left column</h2> <p>Lorem ipsum dolor sit amet, consectetur ...</p> </div> <div id="right-column"> <h2>Right column</h2> <p>Lorem ipsum dolor sit amet, consectetur ...</p> </div> <div id="content"> <h2>Main content</h2> <p>Lorem ipsum dolor sit amet, consectetur ...</p> </div> <div id="footer"> <p>Footer</p> </div> </div>
ul { background-color: red; padding: 20px; text-align: center; } li { display: inline; border: 1px solid black; padding: 10px; background-color: white; }