I'm creating an extremely difficult regex challenge that combines multiple advanced patterns in one text sample. The text includes a complex email with special characters and a hyphenated domain, an international phone number with parentheses and spaces, two different date formats (ISO and European), both IPv4 and full IPv6 addresses, a standard UUID with dashes, a base64 encoded string with precise padding, an HTML element that demands a backreference to verify matching tags, a 24-hour time for... (truncated)