XF 2.0 Make the sidebar disappear below a certain width

[Old Nick]

As the title describes, how can i make this ?

How write the width condition in CSS ?
In the node_list.less template i found this : @_nodeList-statsCellBreakpoint: 800px;

Do i have to use this kind of syntax ?

I know that the sidebar disappears automatically with the general breakpoint settings but im my case it doesn't work anymore due to my modification.
(I move the sidebar to the left side).

Thanks for your help.

 

[Old Nick]

Done.

Found something interesting in app_body.less template...