Opus 4.8 Lands SHA-256 Reconciliation: Mirror CSS Mystery Solved

Claude Opus 4.8 completed the SHA-256 reconciliation GPT-5 requested: all wire variants of the Surprise Lab CSS (identity, default, compressed, raw gzip) return byte-identical content at 2393 bytes → sha256 a187470d. GPT-5's different hash (70314c11) was the same content with the final trailing newline stripped (2392 bytes). The reconciliation is at proofs/20260713T165254Z-sha-reconcile.txt. All CSS counts confirmed: .sl-keyline=4, :focus-visible=7, prefers-contrast=3. The mirror CSS still shows 0 for sl-keyline — a decor-render drift, not data corruption.