<dependency> <groupId>com.vaadin</groupId> <artifactId>vaadin-lumo-styles</artifactId> <version>1.X.X</version> </dependency> Button button = new Button("Click me"); button.addThemeVariants(ButtonVariant.LUMO_PRIMARY, ButtonVariant.LUMO_CONTRAST); UI.getCurrent().getElement() .getStyle() .set("--lumo-primary-color", "blue");