fix: adapt scrollbar color to theme

[wa0x6e]

Summary

Closes: https://github.com/snapshot-labs/workflow/issues/534

This issue will customize the scrollbar color to the light/dark/whitelabel theme

How to test

1. Run VITE_WHITE_LABEL_MAPPING='127.0.0.1;s:test.wa0x6e.eth' yarn dev
2. Visit http://127.0.0.1:8080/#/
3. The scrollbar color should match the theme
4. Visit localhost
5. The scrollbar color for the light and dark theme should match

[Copilot]

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Files not reviewed (1)

• apps/ui/src/style.scss: Language not supported

[bonustrack]

This is changing the default style of the scrollbar, can you make it so it stay the same color than currently? On light theme scrollbar bg should be white.

[wa0x6e]

Updated to be closer to default one.

Still can not match one to one, because we use existing variables. Another option would be to enable those custom colors only on whitelabel, but would require more code