Cell background color for FixedColumn

Hey there! I am using the FixedColumn plug-in and hoping to set a different cell background color for my fixed columns. I have tried to alter these fields in the fixedcolumns.css file but they don't seem to work:

              /* Block out what is behind the fixed column's header and footer *
                 table.DTFC_Cloned thead,
                 table.DTFC_Cloned tfoot {
              background-color: white;
             }

           /* Block out the gap above the scrollbar on the right, when there is a fixed
             * right column
                  */
              div.DTFC_Blocker {
          background-color: white;
              }

Please help!