The latest update lets you customise your UI colors, so you can match it to your in-game HUD colors (if you have changed them).
Go to Settings -> UI Settings and in the UI Colors section you will see a list of settings, each with a 6-character hex code which represents the color.
You can search on the internet for "hex code color picker" to get pages where you can select colors and be told the codes. Just note the codes, and change them on the Settings panel.
Here is a graphic with how the Settings impact the UI panel :