XF 2.0 I need help fixing my Iron on my site

[Godzilla]

The black one is mine. I changed something and I don't know how to fix it back to normal like another picture

 

[Dnyan]

how do you find category id.

Take your mouse cursor on node or category, then you will find its url ending with numbe, that number is that node or category id.

Simply check a number shown at last of that category url link