[Base] Add MUI base example

[siriwatknp]

Add Base example to leverage the CodeSandbox package build in PRs. This PR started from my need to test the fix in #33145 via CodeSandbox (it is possible to manually install via command line but it is a slow process).

This is what the App.tsx looks like:

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• I have followed (at least) the PR section of the contributing guide.

[mui-bot]

No bundle size changes

Generated by 🚫 dangerJS against 6736a45

[michaldudak]

I'm wondering what styling solution should we use. I'm not convinced about emotion. If we want to showcase a CSS-in-JS solution, we could advertise our System here. But also we could go as simple as possible and use plain CSS. Or maybe we need two examples ;)

cc @mnajdova

[siriwatknp]

I'm wondering what styling solution should we use. I'm not convinced about emotion. If we want to showcase a CSS-in-JS solution, we could advertise our System here. But also we could go as simple as possible and use plain CSS. Or maybe we need two examples ;)

cc @mnajdova

I oppose with plain CSS (if I have to create another file and come up with a class name, it is KO for me) but I totally agree with using @mui/system instead of emotion.

[siriwatknp]

@michaldudak Switched to @mui/system. Should we merge this to leverage the CodeSandbox CI?

We can change in the future if we don't want to use @mui/system. Examples are not tied to anything, so I think it is fine.

[michaldudak]

Looks good to me!