Update or Save As your Style Kit
At any point you can customise the values of any Theme Style Kit as you see fit. For example, you might want to change colors, or Font family. To do so, simply hit the blue Update button in the Theme Style Editor after you make your changes. The changes will instantly apply to all the pages that use the same Theme Style Kit.
You also make a copy of your Style Kit without affecting the old one. You can do this with the Save As function which is located under the Theme Style Kit panel.
Once the panel is expanded, click on the Save As button.
In the popup, give your new Style Kit a name and click Save. Your New Style Kit will be saved and applied on the specific page.
If at any point you want to define this new Style Kit as global, you can do so in the Style Kit Settings.