Cascading Style Sheets (CSS) is an open-source programming language used in website building and HTML templates that integrates all relevant information related to web page displays. CSS is used to format the look and structure of a web page, as well as to set design features such as basic layout, colors, and fonts. CSS allows for continuity between different web pages on the website and makes webpage development easier and faster. This book has been created to help readers understand and learn the concepts of CSS. It discusses the fundamental concepts of CSS, including its properties and functions, and guides the reader through creating websites with it. Key Mastering CSS is a valuable resource for anyone who wants to create a website. After finishing this book, readers will quickly build their website with absolute ease, even if they were utterly oblivious to it before.