Change color of text that user types

Hello,

I am looking for some way to change the color of the text that a user enters inside of a textbox.  I know there is a setting to change the color of the heading of a label or textbox, but I do not know of a way to change the color of text that a user types in. 

Also would there be any possible way to have a setting that takes away all the color off of elements on a form?  I mean in the sense of making the buttons on a form black color instead of the usual blue?  And the drop down lists the arrow on them make that black instead of blue? 

My first thought was to somehow use CSS or JavaScript but I am not sure how to go about this.

Thank you!