<header>
    <div id="pagewrap">
        <header id="header">
            <hgroup>
                <h1 id="site-logo">Demo</h1>

                <h2 id="site-description">Site Description</h2>

            </hgroup>

            <nav>
                <ul id="main-nav">
                    <li><a href="http://www.mamicode.com/#">Home</a></li>
                </ul>
            </nav>

            <form id="searchform">
                <input type="search">
            </form>
        </header>

        <div id="content">
            <article> blog post</article>
        </div>

        <aside id="sidebar">
            <section> widget</section>
        </aside>

        <footer id="footer"> footer</footer>

    </div>
</header>

响应式布局简易自适应页面代码