My apologies for my answer being non specific, but you can change the web interface with custom CSS.
I, unfortunately, don't use live tv, so I am unable to find the exact class which is responsible for that particular text heading.
Maybe someone can look for it for you, or you can:
1. Hover your mouse cursor over the item which you wan to change.
2 right click the mouse and select "Inspect Element". This will open "Dev Tools" in your browser.
In most browsers the CSS for the site will be listed on the right hand side.
3. Form there you can locate the class which his responsible for the element in the page.
4. Copy the class name/s
5. Open emby dashboard and select "settings/branding"
6. Copy the class name into the text area.
7. Use "font-size" to make it bigger.
8. Use the keyword "!important" to override emby CSS.
Sorry if that wasn't a huge help.
Edited by chef, 21 September 2017 - 07:56 AM.