Create and modify Windows themes
Using @Superfly's ColorChooser:
You can always do some advanced-editing in Notepad, open the *.theme file directly.
Some items speak for themselves, others need extra explanation.
What are those items and what they do:
The most heavy change is done by altering the so-called 3D Objects field ( a reference to Win7 advanced theme options and below) which is composed of multiple color items stored in the theme:
Followed by Window TEXT:
Active and inactive borders:
*titles are NOT actually window titles (at least they seem to be): other programs can use titles on different places.
*mind the gap and avoid gray-yellow or other not so well balanced combinations.
AppWorkspace: not actually seen in the preview; don't ask where is it:
Goes without saying:
Some changes here:
A few tweaks to note there:
*Not all programs will color though
*Metrics are not working in Win8 / 10
Not all items can be changed using Win10 standard themes. The most changes are possible using a High Contrast theme.