HELP! Navigation bar doesn't show up in IE8

Hi,

I ran into an issue and seeing if someone here might have an answer…
As other people had the issue before, my navigation bar is not showing up in IE8.
The navigation bar from the template provider shows up in IE8 though.

I asked them for help, but they are not willing to.

Here is the link to my site: https://tulsiliving.com/

I tried and added:
<!–[if IE 8]>
<style>
.site-navigation .nav-menu { display: block; }
</style>
<![endif]–>

in the header.php right under </head> but it didn’t work…

Thanks so much!