Content Resize Menu

HTML

<nav role="navigation">
    <ul>
        <li>Home</li>
        <li>
            About
            <ul>
                <li>History</li>
                <li>Our Goals</li>
            </ul>
        </li>
        <li>Products</li>
        <li>Contact</li>
    </ul>
</nav>

CSS

body {
    font-family: sans-serif;
    margin: 20px;
}

ul, li {
    padding: 0;
    list-style-type: none;
}

nav > ul {
    background: #eee;
    border: 1px solid #e6e6e6;
    border-radius: 5px;
    display: table;
    table-layout: fixed;
    width: 100%;
}

nav > ul > li {
    border-right: 1px solid #ddd;
    box-shadow: inset -1px 0 0 #fff;
    display: table-cell;
    padding: 12px 0;
    position: relative;
    text-align: center;
}

nav > ul > li:last-child {
    border: none;
    box-shadow: none;
}

nav > ul > li:hover {
    background: #f2f2f2;
}

nav li ul {
    background: #f2f2f2;
    border: 1px solid #e6e6e6;
    border-top-color: #f2f2f2;
    box-shadow: inset 0 0 15px rgba(0, 0, 0, 0.1);
    display: none;
    padding: 5px 0;
    position: absolute;
    top: 42px;
    width: 100%;
}

nav li:hover ul {
    display: block;
}

nav li li {
    padding: 5px 0;
}