If the event's ticket option is free, show the text "Free" instead of "$0.00".
Update the "Submit Booking" button at the bottom of the booking form to match the button styles used elsewhere on the site (see the "join us" button just below the form as an example).
Adjust styles for mobile resolutions
Testing instructions
Open an Event page from the frontend
Resize the page (including mobile resolutions) and confirm that the cover image gets resized properly (reference)
Changes proposed in this Pull Request
Testing instructions
Mentions https://github.com/a8cteam51/opensource-net/issues/49