Tabpanel Background

I am using a custom style on this form and I am unable to change the grey area in line with the tabs to a custom colour

tabpanel
{
color: Black ;
background-color: #ffffcc;
foreground-color: #ffffcc;
border-style: none ;
border-width: 0px 0px 0px 0px;
}

Thanks

Mostly, you don’t set this color, but set the tabpanel to transparant.
Than the tabpanel will disappear!

Thankyou