Do you have access to FTP on your hosting? If you do then you can do one of the following to regain access to both site and the admin area.
1) Access hosting via FTP and rename the plugin folder - this will effectively disable all active plugins. Check to see if you have access to admin and site. This process is so that we can rule out plugin conflict.
2) If deactivating the plugins in 1 above does not help or if deactivating them will loose data then use this step: Rename the WPCentriK theme folder to something like WPCentriK100 and then check admin.
Once you have access to the Admin area go to Appearance and refresh the screen so that the default theme fully kicks in for the main site. This should now restore full access to both site and the Admin area.
Rename the WPCentriK and in Admin > > Appearance under the theme click "Live Preview" to see how the theme looks under the Customizer - If its blank then we have a problem with the theme itself but if its fine then the problem may well be to do with a plugin conflict.
At this point if the Customizer Live Preview points to a blank theme then delete the theme and install a fresh copy and test again. If its a plugin conflict if you could let me know the list of your plugins I'll run some tests to see where the issue is.