Earth, Top to Bottom

One scroll from the space station down to the Earth's core.

The brief

Build a single vertical scroll journey from the orbit of the International Space Station down to the center of the Earth, with a live altitude/depth counter and a short on-screen note explaining how you handled scale. Mark at least 25 real landmarks along the way (for example cruising airliners, Mount Everest, the deepest point of the ocean, the deepest borehole, the crust–mantle boundary, and the outer and inner core), each with an accurate figure and a one-line fact. Draw every illustration yourself, in code or as assets you generate, and let color, light and ambient sound shift as I descend.