TSRef - TypoScript Reference
4.1.16. treeLevel
Syntax:
[treeLevel = levelnumber, levelnumber, ...]
Comparison:
This checks if the last element of the rootLine is at a level corresponding to one of the figures in "treeLevel". Level = 0 is the "root" of a website. Level=1 is the first menuen
Example:
This changes something with the template, if the page viewed is on level either level 0 (basic) or on level 2
[treeLevel = 0,2]