Admittedly, I got really bored and figured I could make use of that time to attempt an alternate look of Calculator. I applied the .card style class to add some drop shadow. The number buttons (from 0 to 9) are slightly darker to follow the current UI’s design philosophy. I have no intention in getting it to upstream (anymore), because I’m applying CSS classes to unsupported widgets, and even applying classes to child widgets. In other words, it’s fundamentally a hack!
Personally, I like how it looks, but the old UI is fine as well. I’m genuinely curious to know what everyone thinks. It’s just for fun, so it’s nothing serious 
| Current | Alternate Universe | |
|---|---|---|
| Light style (default) |  |
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| Light style (high contrast) |  |
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| Dark style (default) |  |
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| Dark style (high contrast) |  |
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If you want to try it out for yourself, you can clone my fork (https://gitlab.gnome.org/TheEvilSkeleton/gnome-calculator.git), select the “TheEvilSkeleton/card-style-ui”, and press the Run Project button (
) at the top (or pressing Ctrl+Shift+Space) in GNOME Builder.