With the new touch editor, now your page have unlimited hight [1] and width [2] (though we recommend not to increase your page width and hight to extreme sizes, for esthetic purpose).
Note: Keep in mind that your site will become wider only to the right.
This affects how the site will be visible on phones and tablets. When you open a non-mobile site on your phone, it will be displayed starting from the margin limit on the left.