Brief: the below tutorial helps you to view, edit, and add style templates.
1- Login to Cpanel
2- From the side list, select (Styles & layout) > (Styles) >then ( List) as the picture below:
3- A list of styles titles, select the style you want to edit its templates, and press (Design) as below:
4- A list will be appeared above including all style templates, choose the template you want to edit , then press (Display) as below:
5- Edit the template you have selected, then press (Edit) to save.
There are two icons at the bottom of every template; 
- Edit: is used to save the modifications and approve them after editing.
- Delete: is used to delete the template.
If the template is edited, three additional icons will appear as shown in the below picture:
- View previous: is viewing the previous template before editing in a seperate screen, so you can check and compare modifications.
- View Default: is viewing the basic template before any editing in a seperate screen, so you can copy and make use of it.
- RollBack: is restoring and approving the previous template before being modified.