Your theme code seems to be different than the normal generated code of the theme. For example we usually has the theme and Cornerstone version printed as a class of the BODY tag in the HTML, but your's is in a separate BR tag, It seems to be the problem of Child Theme, so apparently you have an old Child Theme that you override few files originally and did your customization on. Now it seems that the original files are changed and that is why you need to update your Child Theme.
Also Test for a plugin conflict. You can do this by deactivating all third-party plugins, and see if the problem remains. If it's fixed, you'll know a plugin caused the problem, and you can narrow down which one by reactivating them one at a time.
If you still are experiencing the issue kindly get back to us with the result of the steps above and URL/User/Pass of your WordPress dashboard using the Secure Note functionality of the post to follow up the case.