In this video, I break down how we “vibe coded” a production-grade, high-end 3D product website in a single weekend—one developer, no agency, just a long conversation with an AI agent. The project is Slam Dunk 3D: scroll-driven cinematic transitions, a hyperreal 3D basketball that morphs through sections, physics-style motion, and an “add to cart” moment where the ball flies into a DOM cart icon with hover + sound effects. The stack is React 19, Three.js via React Three Fiber, and GSAP for scroll animation—built through Gemini in Google AI Studio. But the real point isn’t “AI magically built a website.” It’s the structured agentic workflow we used: research references before prompting, define constraints upfront, write a master prompt that locks the design, iterate surgically (with measurable feedback), solve one problem at a time, and—most importantly—understand what you ship. I show why most people get mediocre AI output (vague prompts, broad fixes, regression), and how tight context + targeted iteration gets you to results that used to take full teams. The takeaway: frontend isn’t “dead,” but the job is shifting—your edge is vision, taste, and the ability to direct AI with precision.