Interactive DNA Helix Model (2D)

This 2D companion projects the 3D DNA helix model's own geometry onto a flat canvas rather than reskinning it: each base pair sits at height i × 0.34 nm along the helix axis and at azimuthal angle i × twist × (π/5.2) around it, exactly the rise-per-base-pair and twist-angle formulas the 3D engine uses, so dropping the depth axis and shading by it still produces a recognisably rotating double helix. Every rung is a real complementary base pair — adenine always opposite thymine, guanine always opposite cytosine — drawn back-to-front by depth for a simple pseudo-3D read, while a live panel tracks helix length, twist angle per base pair, completed rotations and GC content as the base-pair count, twist rate, rotation speed and zoom sliders are adjusted.