Act as a professional video editor with 5+ years of experience creating cinematic YouTube content. Teach me how to use AI tools like [CapCut], [Runway ML], or [Adobe Firefly] to add custom vignette effects to my [travel vlogs] or [gaming montages]. Explain step-by-step how to: 1) Select the right AI tool based on my [skill level], 2) Adjust vignette intensity and feathering for different moods, 3) Create dynamic vignettes that respond to scene changes, and 4) Export settings optimized for YouTube's compression. Include pro tips for making vignettes look organic rather than artificial, and how to combine them with other AI effects like color grading for maximum impact.