How do I remove the jumping effect?

[Nauman_Tanwir]

This is my site http://classichits.ie/

Kindly, check the attachment to understand which part of the site I am talking about.

I have tried implementing z-index to remove the jumping effect, but no success.

I think I choosing wrong class. Please help me out. Thanks.

[SamA74]

It is the addition of the 2px border on hover that is causing this. I thought the box-sizing would take care of that, but it does not.
Try adding an invisible 2px border to the non-hovered .nm > li, either `transparent or the background colour.

Edit
Another issue, the “Classic Hits” at the top is obscuring part of the menu.

[Nauman_Tanwir]

Thanks for replying back.

I am sorry. I am kinda newbie, don’t know much around.

Can you please tell me how to implement what you just suggested. Thanks.

[Nauman_Tanwir]

It worked mate. Thanks again.

[SamA74]

In the file 4fm.css at line 151 is the selector for .nm > li add a border to that to match the size of the hover border (.mn > li:hover)

border: 2px solid transparent;

Edit
Looks like you got it.