How to apply css formatting for Webview in android?

In below example you will find that the css formatting is applied in onFinished method of webview .......

mWebView = (WebView) findViewById(R.id.termswebview);
mWebView.setBackgroundColor(Color.parseColor("#000000"));
mWebView.getSettings().setJavaScriptEnabled(true);

mWebView.setWebViewClient(new WebViewClient());
mWebView.getSettings().setBuiltInZoomControls(true);
mWebView.getSettings().setUseWideViewPort(true);


mWebView.setWebViewClient(new WebViewClient() {
   public boolean shouldOverrideUrlLoading(WebView view, String url) {
mWebView.loadUrl(url);
return false;
   }

   @Override
   public void onPageFinished(WebView view, String url) {
mWebView.loadUrl("javascript:document.getElementsByTagName('html')              [0].innerHTML+='<style>*{color:#fff}</style>';");

   }
});

mWebView.loadUrl(url);