Hi Aaron.
Each custom panel or device is free to use colours however they choose but we have defined a few constants in DashBoard as recommendations.
In this case, uncoloured is simply the default for a new button - it is also how most of the selection buttons look when they are toggled off.
The blue is recommended as a default for 'toggled on'. It provides a stronger visual feedback that a toggle button is pressed than just leaving it uncoloured. We recommend this style for most toggle buttons where you are selecting a parameter's value.
The pink (or purple depending on where you draw the line between the colours) is intended to be used for navigation buttons. So, if your button group is used to select between active user interfaces or selected tabs, this is the colour/style we recommend.
The light grey buttons are intended to be used as "commit" actions (apply, cancel, etc.)
That's about all we have in terms of pre-defined button styles in DashBoard. Again, they are considered recommendations and you'll find many choose to come up with their own styles and meanings for colours.
Hope this helps.
James
#DashBoard