fix(alert, callout): change text color of Alert and Callout

[Priyesh1311421]

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Closes #587

[huyenltnguyen]

Thanks @Priyesh1311421.

Just a quick note for next time: it's best to avoid editing changes directly on your main branch. Instead, you should create a separate branch for your work. This helps keep the main branch clean and allows you to make changes for multiple issues in parallel.