From Nookipedia, the Animal Crossing wiki

! style="border-bottom:4px solid #FFDD66; border-right: 2px solid #FFDD66; border-left: 2px solid #FFDD66; background-color:#FFFFCC; color:#666;


Used in Template:TableHeader to reduce template clutter and apply formatting to table column headers. Acceptable parameters are "left" and "right" to generate {{roundyleft}} or {{roundyright}} tags respectively at the end of the style code before the final pipe.