Hello,
You can override any CSS style in my add-on. See the Options page / General tab / "Custom CSS styles:".
For example, to change color of dials heading, use this:

.dials > a > div > div {
background: lightblue !important;
}

And to make group list more colorful, use this:

#groups {
background-color: rgba(255, 209, 57, 0.6) !important;
}
#groups > .selected {
background-color: orange !important;
}

You can create also new styles, just inspect the element you want to change and create new CSS rule. However make sure to pick the theme - black or while, depending on whether your final theme will be dark or light.

If you have more questions, feel free to write me to my support e-mail.


Best regards,
Juraj Mäsiar