For both headlines and paragraphs, you have the option to choose the group of text that you want to change the color of. You can do this by clicking a Headline or paragraph element and then edit the color in the right-hand style panel. Highlight the text(s) and then select the color below the Text style options.
In order to change a shape’s background, click on it. This will open the menu on the right. Here you can select the background color:
For backgrounds, you can change the color for a block or the whole page.
Adjusting the background color for your whole page is done from the right-side Settings menu. Choose Page Background, then select the color you wish:
Alternatively, to modify the color only for a block of your landing page, click on the Block Style icon for the block in question: