There are several ways to change the theme color of an object. Currently, there is no way of updating the color of multiple existing objects on your canvas. You will need to update the object color individually. We will go over the following:
Change the theme color of an existing object
Double-click on the object.
From the top navigation bar of the pop-up, click on Customize.
Select a color and click save.
Change the theme color of new objects
If you have existing objects on your canvas, the color of the objects will not change. Only new objects that you add to the canvas will use the new color that you select.
Click on the gear icon above your canvas.
Select a theme color and click save.
New objects that you add to your canvas will have the new color.