Rapid CSS Editor is a lightweight and powerful HTML and CSS3 editor designed specifically for front-end development. It has features such as fast startup, intelligent code completion, syntax highlighting, code snippet library, built-in AI assistant, multi browser preview, FTP/SFTP direct editing, etc. It supports multiple languages such as HTML, CSS, JavaScript, PHP, and is compatible with HTML5 and CSS3 standards. It is suitable for beginners and experts to use and can significantly improve development efficiency with high cost-effectiveness.