jQuery Grid Plugin - jqGrid

Inside Site.Master file I have a reference to main.css which has: Td { background-color: #FFFFFF; }

Inside MyAspPage.aspx file I have a reference to ui.jqgrid-custom.css:

.ui-state-highlight ui-widget-content .ui-state-highlight,.ui-widget-header .ui-state-highlight {

color: red !important; background: blue !important;

}

When I uncomment the "Td {background-color: #FFFFFF; }" inside main.css my grid doesn't seem to highlight the colors red and blue. If I comment out my main.css the jqgrid works great, however not sure why it doesn't override main.css.

Any help would be appreciated.