love the style, colors and the cookie popup from https://karboosx.net/ https://karboosx.net/. Anyone knows if its an open source framework/style/tool being use

love the style, colors and the cookie popup from https://karboosx.net/ https://karboosx.net/. Anyone knows if its an open source framework/style/tool being used here or it just the web dev skills of the author that are superb?