08. Challenge

How might you achieve the three column design indicated in the wireframe below. You will need to add some new HTML for the left menu with dummy links such as:

<div class="sidebar">
    <ul>
        <li><a href="#">Link 1</a></li>
        <li><a href="#">Link 3</a></li>
        <li><a href="#">Link 3</a></li>
    </ul>
</div>

Amend the CSS rule such that the left menu and contact details take up around 25% of the available flex space compared to the main contents 50%.