Hi I just added Google\'s No CAPTCHA reCAPTCHA to my website, and I am running into a small little issue. It does NOT fit on my mobile website, and that is
I successfully implemented Geek Goddess' solution. The main issue with it is that it may not work on all browsers. Now, however, there is a simple solution provided by Google.
With reCAPTCHA version 2.0, there are new rules for the display of the widget and Google added tag attributes that change the way it is rendered.
The tag data-size can take the values of "normal", which is the default, and "compact", which fits in mobile device screens. This is what the compact widget looks like.

It is not the best looking widget, but it fits with less work than the other solutions.
For more attributes, check Google's reCAPTCHA v2.0 documentation