Added box sizing precaution.
Added variables for all the media query limiters.

Added the variables:
    $topMaxWidth
    $topMinWidth
    $medMaxWidth
    $botMaxWidth
    $botMinWidth
Applied them to all the media queries. 
The added scalability allows the change of quick media queries from one area.
Making it easier to align media queries from CSS to JS.
Merge pull request #3 from PaulAndreRada/master

Made the media queries easier to scale by using variables.