<dependency> <groupId>com.vaadin</groupId> <artifactId>vaadin-lumo-styles</artifactId> <version>1.5.0</version> </dependency> import com.vaadin.flow.theme.Theme; import com.vaadin.flow.theme.lumo.Lumo; @Theme(value = Lumo.class, variant = Lumo.LIGHT) public class AppConfig { } Button button = new Button("Click me"); button.addClassName("primary"); Button button = new Button("Click me"); button.getElement().setAttribute("style", "background-color: var(--lumo-primary-color); color: white;"); Button button = new Button("Click me"); button.addClassName("custom-button");