s4-nosetwidth messes up dialogbox

Question

since im doing a branding for my SP enterprise server which uses a fixed and centered layout i need to use the s4-nosetwidth class to adjust my width..

as you can see in the screenshot below this messes up my dialogboxes.. anyone ideas how the width from the class is not applied to dialog boxes?

*small reso*/
@media screen and (max-width: 1123px)
{ 
    .s4-nosetwidth{
        width:990px !important;
    }
    .s4-ca{
        margin-left:0px;
        margin-top:10px;
        margin-right:5px;
        width:80%;
        float:left;
    }
    .ms-dialog .s4-nosetwidth
    {
        width:auto !important;
        overflow:hidden !important;
    } 
}

Answer 1

i had a background applied to my workspace container which stretched the whole dialog-box. Now the background is applied to my s4-bodyContainer which basically fixed all my troubles.

Answer 2

you can add .ms-dialog then the css class that sets your width and change that width to auto. Sometimes it takes a bit of work around to get it just right. Basically use the .ms-dialog and reverse the width, or remove the background image or color, anything that messes up the dialog box.

Else I make sure I just use my custom master on the site master page and leave my system master page to use the v4.master.