Was the UI kit based on a library or fully custom?

A UI kit can be built either on the basis of a ready-made component library (for example, Material-UI, Ant Design, Bootstrap) or be completely custom-developed from scratch to meet specific project requirements. Using ready-made libraries speeds up development and ensures consistency, but a custom UI kit allows for a closer match to the design and the unique needs of the product.

Example: if a project requires a strict corporate style and non-standard interactive elements, a custom UI kit is often chosen. If speed and standardization are important, popular libraries are used.