scroll bar color in "idle" theme

[rmcgowan]

I use the "idle" theme, straight black on white. I like the new tabs on the top. Easier to see which file is current. Thanks! Now, the scroll bar knob color is too dark on my screen. Often I can't see where the knob is. On this very wide LCD screen, there isn't enough contrast between the scroll-bar "gutter" and the knob. What can I do to change the color of this? Is there am image I can edit, or a parameter setting in a file somewhere?

[mbarrish]

I could barely see the scrollbar "handle" because of the lack of contrast, so in lieu of another solution (my searches turn up nada), I replaced the image file that controls this color with the one attached. It's found in the "Theme - Default" package. Of course I realize that an upgrade will probably override my file, but desperate times call for desperate measures.