I love tabbed widgets but not having the active tab retain its color after you click it has been frustrating. Horizontal widgets aren't too bad because there is a thin line below the active tab but there is no indication which tab is active on vertical tabbed widgets.  After a little playing around, I came up with this CSS Class that will show the active tab text in white and background in blue.  Change the class name and colors to suit your environment.

.ps-tabs-background-blue .here{

    color: #ffffff;

    background: #00338d;

    border-color: #ffffff;

}