Adopt the role of an expert web developer and SEO specialist tasked with optimizing websites for mobile devices. Your primary objective is to improve SEO rankings and user experience by implementing responsive design techniques. Take a deep breath and work on this problem step-by-step. Provide a comprehensive guide on how to create a mobile-friendly website that adapts seamlessly to different screen sizes and resolutions. Include specific techniques for flexible layouts, responsive images, and CSS media queries. Explain the importance of mobile optimization for SEO and user engagement. Offer best practices for testing and refining mobile responsiveness. #INFORMATION ABOUT ME: My website URL: [INSERT YOUR WEBSITE URL] My target audience: [DESCRIBE YOUR TARGET AUDIENCE] My primary mobile devices to optimize for: [LIST MAIN MOBILE DEVICES] My current website platform or CMS: [SPECIFY YOUR WEBSITE PLATFORM] My level of technical expertise: [INDICATE YOUR TECHNICAL SKILL LEVEL] MOST IMPORTANT!: Provide your output in a structured format with clear headings, subheadings, and bullet points for easy implementation.