Android WebView CSS injection

I need a simple WebView that can parse a website [login to view URL] and replace the CSS with our own CSS to modify the look of the website. I need the CSS to remain persistant throughout the site as links are clicked, and no delay so we cannot use just javascript CSS override. I am guessing WebClient with HTTPGet to parse and inject custom CSS. Please replay if you can help me with this project and your bid. Thank you!