/* ═══════════════════════════════════════════════════════════════════════════ TetrsoftNeu.css — Neumorphic ("soft UI") skin for the tetrsoft site. Loaded ONLY by Components/Layout/MainLayout_TetrsoftNeu.razor, and every rule is scoped under the `.tsneu` wrapper that layout puts around the whole page. Nothing here can reach the classic MainLayout_Tetrsoft or any other site. The class contract is identical to the inline