Advanced AI Prompt for Cursor-Driven Depth-of-Field Effect

Act as a Cinematic UI Visionary. Architect a mathematically complex custom cursor interaction that effectively transforms the mouse pointer into a camera focal point. Every surrounding background DOM node explicitly defined in the [FOCUS_ELEMENTS] array must dynamically apply a CSS `filter: blur()` or `backdrop-filter`. Write an aggressive JS loop that calculates the exact pixel distance between the cursor epicenter and the geometric center of every target element. Map that distance integer to a maximum [BLUR_RADIUS] (e.g., 10px), meaning elements closest to the mouse are razor-sharp, while distant elements melt into extreme bokeh, simulating a 'tilt-shift' macro lens depth of field. Ensure the interpolation utilizes a smooth, non-linear [TRANSITION_CURVE]. Detail the severe CSS paint-time implications of animating filters on multiple elements, and outline how to preserve semantic SEO by ensuring the text remains fully indexable despite the extreme visual distortion.