Read the original PDF on the left. The lab follows your page automatically. Choose a topic in the sidebar, or explore the controls on the right.
Drag a 3D model to rotate it. Use the mouse wheel or a pinch gesture to zoom. Diagrams are idealized teaching models; whole boundary atoms are drawn for clarity.
Everything runs locally. No AI service, accounts, tracking, or API keys. The PDF is the original lecture; companion notes clarify a few terminology and formula issues.