Code:
{if $main eq "catalog" and $current_category.category eq ""}
{ 3 column layout }
{else}
{ 2 column layout }
{/if}
HTH
__________________
Developing in 4.7.x now (Dipping into v5 - Slowly!)
Have used 4.1.x, 4.2.x, 4.4.x, 4.5.x, 4.6.x & 4.7.x
Multiple Instances of X-Cart
MySQL 5.6.37
CentOS 7.4
Chamber Internet - Lancashire, United Kingdom
http://www.chamberelancs.co.uk