Lumo Style Properties
The style properties, such as colors, typography and other visual styles that define the Lumo theme.
Lumo is based on a set of style properties – CSS custom properties – representing colors, fonts, sizes and other styles, that can be customized by providing new values for them in a CSS stylesheet, either globally, or scoped to a certain component type or instance.

A small sample of Lumo style properties and their use in Vaadin components
html {
--lumo-primary-color: green;
--lumo-font-family: 'Roboto';
}
Lumo style properties can also be used in CSS instead of hard-coded literal values, through the var()
function:
div {
border: 1px solid var(--lumo-primary-color);
border-radius: var(--lumo-border-radius-m);
}
The Styling Vaadin Components section provides more details on using Lumo properties to modify the look and feel of Vaadin components. The Styling Other UI Elements section provides more details on using Lumo properties to style other UI elements.