Update responsiveUtils.js

[xcqwan]

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[cr-gpt]

the code review

The code looks good and there are no obvious bugs. However, there are some improvements that can be made.

First, the code should use more descriptive variable names. For example, instead of "md", "sm" and "xs", more descriptive names such as "medium", "small" and "extraSmall" could be used to make the code easier to read and understand.

Second, it might be a good idea to add a comment above the ResponsiveLayout type definition to explain what it is used for. This would help other developers understand the purpose of the type.

Third, it might also be a good idea to add an explicit type for the Breakpoint variable. This would make it easier to understand what values are expected for the variable.

Finally, a linter can be used to ensure that the code is formatted correctly and to flag any potential errors or warnings.

Overall, the code looks good and should work as intended with the suggested improvements.