You can create and customize a website color palette in the global styles settings.
Within the editor, expand the Styles panel on the left and open the Colors tab. Here, you can select from a variety of predesigned color palettes:
To change colors within the palette, click Change colors and select a color to customize. You can always go back to the original color palette by clicking on Reset colors:
Once you set your custom colors, they're suggested for you to use all across your site, but you still can edit the appearance of individual elements and sections manually anytime.