Create a three-column layout with CSS

For this exercise, I want you to add a third column to your design.

In addition to adding third column I also want you to change the design from a fixed (pixel-based) design to a liquid (percentage-based) design. You'll have to work out the percentages of all the sidebars and the main content area, as well as the container. (My recommendation is to set the container to somewhere between 70%-80%.)

You will also want to add a max-width and a min-width to your container. These will prevent the page from stretching out too wide on big screens and from going too small on a small screen. These will be added into your container rule:

max-width: 1260px;

min-width: 780px;

(You can play with different values here to see how this affects the look of your page.)