1.1.0 introduced the ability to style your tags.
This is now a small tutorial to show the possibilities.
While editing the tag details in the ACP, you can define specific css code for the tag.
The content of the "Style" field needs to be valid CSS code.
Most of the time you'll only want to set the background and text color, following code would result in a blue tag.
background-color: blue !important;
color: white !important;