There are several ways in which you can change the appearance of a Sitefinity website, depending on the scope of the change you are looking for.
If you want to change the layout of the page, you can create a new masterpage and upload it to create a new template. More information on how to do this, you can find here:
To create a custom css file and add any images or assets you should create a new theme. By combining the template and a theme you will get the complete control over the look and feel of your pages. More information on how to create a theme you can find here:
If you whish to change the layout of a particular control you will need to modify the control templates. All control templates (for public controls) are located in this folder: ~/Sitefinity/ControlTemplates
Finally, it is also possible to change the appearance of the administrative side of Sitefinity. The admin control templates are located in this folder: ~/Sitefinity/Admin/ControlTemplates
You can also change the appearance of admin side pages and modify the CSS. More information on this you can find here:
Bear in mind that you are not allowed to remove the Sitefinity logo unless you specifically get a permission from our business development department. Otherwise you would be breaching the terms of the license agreement.
I hope you'll find this information helpful. Let us know if there is anything else we can do for you.
the Telerik team
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