I've searched all over for this but I can only find how to change/modify styles for input, select and button elements.
What I want to do is remove all shadows, borders, background, icons etc everything except the value itself, across all browsers and mobile.
You can use normalize.css for improve the cross-browser rendering. You can update the following class in the normalize.css.
Please add the following style to the above elements.
Style the input tag via css.
See: http://www.w3schools.com/tags/tag_input.asp
input etc.:
Buttons:
Reset the css: http://cssreset.com/
Nice looking reset: https://necolas.github.io/normalize.css/