Location of the internal navigation bar

Hi, I am a newbie to HTML and I am getting unsatisfactory results when applying it.
When I enter the following code in SSX and apply it in the wiki:

image

image

My internal navigation bar showed the following phenomenon:

image

How can I improve my code so that no matter how the window changes, the navigation bar always occupies the middle of the body and the right panel boundary?

This looks like a generic CSS issue. I’m not sure what’s specific to XWiki. You should be able to achieve the same result using the {{html}} macro.

Sorry for that.

Thank you for your response.