Fixed multiple bugs

【Contents of the fix】
■Fixed a bug in “Staff” and “Clinic” custom post types that hides the staff name and article name when the thumbnail is hidden.
■Fixed a bug in “Column” and “Campaign” custom post types that when you hide the thumbnail, the category name will also be hidden.

【Fixed files】
single-campaign.php
single-clinic.php
single-column.php
single-staff.php
style.css