Where is Style.css of Wyzi Theme ?
The style.css of the new template layout ( this https://wyzi.net/listing/ ) is indeed different from older template layout ( this https://wyzi.net )
To be exact about my answer now Old Layout Style.css is located in
And the new Layout style.css is located in
This is necessary to have two different layouts.
But in case you want to edit css, it is not recommended to alter those files directly as all your changes will be lost once you update your theme. Alternatively you can go to Theme Options > Custom Css and place your custom CSS in there.
Another option, if you have plenty of changes in CSS and functions you want to do, you can create a child theme. You can read more how to create a child theme here:
But that is just a start, you can google WordPress Child theme and learn more how to dig more into Child theme that will let you alter CSS and maybe create your own functions without losing your edits on every update, especially that we update frequently 😀