Library — books as evidence
Read the real pages; prove it in the exercises.
The full Tatva books (82 chapters, 3,561 pages) are served as lossless page renders with the book's own clickable index — formulas are never re-typeset, so they cannot be silently wrong. Reading pages earns nothing by design: evidence starts when you answer the book's exercises.
Book answers cap ability at 0.60 — the lowest rung of the evidence ladder. Solution-first is logged as an encounter with zero credit. The shelf is grade-scoped like everything else, with an explicit toggle when you want next year's books early.
See it live — free