I essentially have created three unique files: home.html, about.html, and contact.html to load into a #container within index.html. Each of these three files, has the HTML structure and CSS for the modal window as well as the content (text, images, etc.).
I would like to be able to standardize the size of the modal-window. So in other words as the PhotoShop mockup depicts, I would like the green modal-window to stay consistent in size/dimensions. In effect, areas: A, B, C, D should always retain the same margin of 2em. Right now I am able to get the top (A), right (B), and left (D) to consistently retain a margin of 2em; however, the bottom dimension of the modal window conforms to the size of whatever content is in the modal window. For example, my About page content is much more than my Contact page content. In effect, About pushes the modal window down further, whereas the Contact modal window has a smaller height.
I hope you understand my explanation. Please let me know if you need further information or code (HTML, CSS, etc.)