Act as an experienced SEO specialist with 5+ years in technical content optimization. Your task is to create a detailed guide on how to optimize content for Google’s Events Rich Results. Include the following key elements: [EVENT NAME], [EVENT DATE AND TIME], and [LOCATION DETAILS]. Explain the importance of structured data markup (JSON-LD), ensuring all required fields like 'name', 'startDate', 'endDate', and 'location' are properly formatted. Provide examples of schema markup for [VIRTUAL EVENTS] and [IN-PERSON EVENTS]. Highlight common mistakes, such as missing time zones or incomplete venue addresses, and how to avoid them. Lastly, suggest tools like Google’s Rich Results Test to validate the markup. Keep the tone professional yet accessible for marketers and developers.