Website Customer-Support Chatbot

I need a small, self-contained chat widget that visitors can open on my website to receive instant customer-support replies. For now the bot only has to match incoming questions to a set of simple, pre-defined answers that I will provide as a CSV or JSON file... (Budget: £20 - £250 GBP, Jobs: API, Chatbot Development, Frontend Development, HTML, JavaScript, PHP, Python, Web Development)