WordPress TinyMCE editor text fix

TL;DWTT (Too long, didn't want to type):
In your style.css file in your theme, add this to control the text color in the Editor field in WordPress Pages and Post:

.mceContentBody.post.wp-editor {}

Add the color you want.

Don't forget to trigger the Editor Styles by adding this to your functions.php file:

add_editor_style( '/editor-style.css' );