Closer - That helped as now the link is active when there is a Big_Pic_Name and it's dead when there is none. However, now when you click on an active Product Name/Title, I am getting this error 'You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'color=' at line 1.'
The code seems to be constructing the link now with extra characters - <font%20color= added to the link to make .../products_detail.php?ID=4<font%20color=
Tried several moves with the <font> piece of code but they all failed. Maybe you can see the syntax error. Latest products_results.php file and link attached.