Vulcan uses the Vuetify Material Design framework as a basis for its User Interface and Interaction design patterns.
It's an extensive framework, with a huge list of UI Components that are easy to use and have many properties for all kinds of use-cases.
Vulcan Components have access to the Vuetify library, so you can go ahead and use it inside your custom components.
Take a look at the excellent Vuetify documentation.
Through Vuetify, you also have access to the Material Icons set.