PrimeVue is a design agnostic library so unlike some other UI libraries it does not enforce a certain styling such as material design. Styling is decoupled from the components using the themes instead. A theme consists of two parts; base and preset. The base is the style rules with CSS variables as placeholders whereas the preset is a set of design tokens to feed a base by mapping the tokens to CSS variables. A base may be configured with different - presets, currently Aura is the only preset and in upcoming version more presets will be available. + presets, currently Aura, Lara and Nora are the available presets and in upcoming version more presets will be available such as Material Design.
The core of the styled mode architecture is based on a concept named design token, a preset defines the token configuration in 3 tiers; primitive, semantic and component.