Add modern Minecraft background and button style

[LeoDreamer2004]

• Add backgrounds for Minecraft 1.21.9 1.21.11 26.1 26.2 from Minecraft Wiki
• Apply modern outline-style button textures for Minecraft>=1.15 instead of blue highlighting

[Lxtharia]

Ohh, thank you. I need to try this out when I get the chance (might take a week or two though x)

[LeoDreamer2004]

any reply？

[Lxtharia]

Thanks for the reminder (I forgot). I'll try to test this out later today, feel free to remind me again tomorrow in case I forget :)

[Lxtharia]

Looks good so far :) I didn't even realize that the button style changed in new versions and that the new version is named "26" instead of "1.26".

However, you would only get the button style when manually choosing a background, but I assume a lot of people use the python script to automatically shuffle the backgrounds. I think it would be better for the python script to handle this.

Tbh, the bash script is a mess and I need to adjust that anyway, but if you can just add the behavior to the update_theme.py script, I'll merge this and update the installation script when I find the time and energy.

[LeoDreamer2004]

Okay, done.

[Lxtharia]

Thank you very much!