problem with menu in Isis template

-- HikaShop version -- : 2.5.0
-- Joomla version -- : 3.4.1

Hi,
Recently I upgraded (successfully at last) my site from joomla 2.5 to 3.4.1.
But I have a problem with isis template. The menu below tabs position is fixed in my backend. I send you 2 screenshots (#1 - #2).




I looked for a solution in forum and found it but the option "menu position" in general display options don't display in my backend (I send you another screenshot - #3)


Thanks you in advance for your help.

Hi,

Please check the backend CSS file that you are using.
It looks like you do not have the "default" one which contains CSS rules for the configuration sub menu.

Regards,

:oops: :oops:
Fixed. Thanks.
I was using a custom CSS file in the backend (but I don't know why I changed it :S )