2-Column Page Layout

With navigation on the left

<div id="wrapper">
    <nav>
    </nav>

    <div id="rightcol">
        <header>
        </header>
        <main>
        </main>
        <footer>
        </footer>
    </div>
</div>

#wrapper {
    width: 80%;
    margin-left: auto;
    margin-right: auto;
    background-color: #b3c7e6;
}

With top header and left navigation

<div id="wrapper">

    <header>
    </header>
    <nav>
    </nav>

    <div id="rightcol">
        <main>
        </main>
        <footer>
        </footer>
    </div>
</div>

#wrapper {
    width: 80%;
    margin-left: auto;
    margin-right: auto;
    background-color: #b3c7e6;
}