theme doesn't work on internet explorer

i just finished costumizing the activello theme and i noticed that it doesn’t work on Internet Explorer. What should i do?
this is my site

Hi @kate,

I hope you are well today and thanks for posting here.

Could you please tell me on which Internet Explorer version it is not working?

Also do you mean it’s not displaying at all or having issue with specific part of the site? If yes then please share the screenshot of it.

Kind Regards,