{"content":"I've designed an extremely difficult regex challenge that combines multiple complex pattern types requiring advanced matching techniques. This challenge includes: 1) Complex email formats with quoted local parts, embedded special characters, and unusual domain formats, 2) Date/time formats with varying separators and timezone notations, 3) URLs with complex query parameters, fragments, and unusual schemes, 4) JSON path expressions with deeply nested structures and escaped quotations, 5) Code snippets with nested function calls and special character escaping, 6) XML/HTML with complex attribute values containing escaped JSON, and 7) International phone numbers with varying formats and extensions. Each category contains both valid targets and similar-looking non-targets (distractors) that require precise pattern matching to differentiate. Most items contain regex metacharacters that need careful escaping. This would require sophisticated use of alternation, character classes, ... (truncated)