Hackerskeyboard: Key outlines are invisible on e-paper

[yodrew]

Thanks for your cool keyboard.

Below is how Material Light theme appears on my e-paper tablet (Onyx Boox Max 3). I think the outlines of keys are supposed to be visible. A simple black and white theme might fix it. I'm a very novice programmer, but if you point me to the right file, maybe I could do it.

Now, the outlines are visible in the Stone theme. But then their gradients and colors make them hard to see on a grayscale screen.

[TPS]

Just _(non-constructively)_ commenting, I'm astonished HK displays as well as it does on e-paper. I can't imagine that such could've even been planned for at the time the underlying _(relatively ancient)_ codebase was established.

Also, this overlaps #819.

[yodrew]

Yes, it is very crisp. This e-paper has high resolution (225 DPI).

Oh, I should add that when I touch the keys, the grey box they are in appears.

[solroot]

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