If you use system fonts and colors, your winforms application is dominated by the font and operating system settings.
For example, if the ForeColor property for your buttons is set to ControlText (system color) and not black (for example), your application will be displayed using any ForeColor property of the operating system.
Also keep in mind that adjusting the font size of the operating system will affect the layout of your forms. If the font size of the operating system is set to 125% or 150%, overlap problems may occur.
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