TITLE: Grandmaster's Study FILE: 070-chess-study.html === PROMPT (exact prompt used) === Create "Grandmaster's Study", an elegant, playable two-player chess board (local hot-seat). A luxurious board of maple (#e8d0aa) and walnut (#8a5a3b) squares with subtle wood-grain gradients, a lacquered frame with brass corner fittings, and file/rank coordinates engraved in serif. Pieces drawn in SVG as original Staunton-inspired silhouettes — ivory (#f7f0e1, warm shading) and ebony (#1e1b18, soft highlights). Full legal chess rules: legal move generation with check detection, castling, en passant, promotion (with a chooser), and checkmate/stalemate detection. UX: click or drag pieces; legal moves shown as subtle dots/rings; last move highlighted; check shown as a red glow on the king; a move list in algebraic notation in a side panel styled like a score sheet; a captured-pieces tray; undo; flip board; new game. Smooth gliding piece animations and a soft synthesized "clack" on each move (toggle). Responsive: the board fits the width on phones with the panel below. Typography: a classic serif. SHARED REQUIREMENTS (apply to every page in this 100-page collection): 1. One standalone HTML5 file. All CSS inline in