You can change the snip's styling by adding your own custom CSS per profile.
NOTE: Custom HTML & Code is a Business feature - upgrade to business at http://snip.ly/upgrade/
Step by Step:
1. Go to 'Profiles' (under 'Account Settings')
2. Click the blue edit button on the relevant profile
3. Put your custom CSS and/or HTML in 'Custom HTML & Code' (click 'Update Profile' to save)
That's it! If you have any issues with custom css, don't hesitate to reach out by emailing email@example.com