Prime Theme Highlight Colour

[alexmalt001]

On my Prime (G1, not sure if this is different on G2) I tend to use the Dark Mode, and I have noticed that none of the available highlight colours are very visible if you look at the screen from even slightly below due to the quite poor viewing angles on the Prime, making it a real pain to see if I have selected the right thing from my history. In the apps menu, it seems that a lot of the colours there also become washed out when viewed from below, however the relatively bright orange of apps like 'Solve' seems to remain quite visible, so ideally I would use this as my highlight colour. Is there an option to set a custom highlight colour on the Prime (i.e. RGB), or maybe a 3rd party addon which allows custom highlight colours? The 'Theme' variable only seems to allow selection of the colours available in the menu, though perhaps I could redefine the RGB value of one of these existing colours?