Applying CSS dynamically in Web app using Javascript

This code:

$("#btnaccept").css("bordercolor","purple");

issued in the Click delegate of a commandbutton, btnaccept, in a Canvas section in theory should set the border color to purple, using JSQuery syntax.

It doesn't error, but neither does it do anything.

I must be missing something...

I know i could just set bordercolor (that works, of course), but what I really want is a boxshadow.

$("#btnaccept").css("boxShadow","inset 1em");

The line is running (Chrome inspector, breakpoint), no error thrown, no change in the color (for the first) or boxshadow (for the second).

thanks,

Hank