TITLE: Crate Yard — Sokoban Shift

FULL PROMPT:
Create a self-contained, single-file interactive page titled "Crate Yard — Sokoban Shift". Render a Sokoban warehouse puzzle on a canvas sized to the level: beveled concrete walls, checkered floor tiles, dashed amber dock pads, wooden crates drawn with gradients, cross-bracing and drop shadows (glowing amber when they sit on a pad), and a teal worker dot with a facing wedge. Six hand-authored, machine-verified-solvable levels ship with the page — each solvable, none trivial (6 to 28 pushes) — listed in a side shift log with a ★ once cleared, best move count persisted in localStorage. Arrow keys or WASD walk and shove; pushing checks the cell beyond for walls and other crates; the whole state is snapshotted before every move so Z undoes arbitrarily far, R restarts, N/P switch shifts. Player and pushed crate interpolate over ~130ms with eased motion. HUD shows shift name, moves, pushes and best. Clearing every crate onto its pad overlays "SHIFT COMPLETE" with the score. Everything inline, no external resources.

INTENDED DESIGN DESCRIPTION:
The page is a night shift clipboard in a lumber yard: moss-dark greens, safety-orange headings, crates that look lifted from a hardware catalogue. The craft is honest puzzle engineering — six levels that were verified solvable by a search algorithm before shipping, dead-corner consequences, and an undo that makes experimentation free.

MAJOR VISUAL TECHNIQUES:
- Level-driven canvas sizing (tiles × 44px) with per-row parsing of #, ., $, *, @, + glyphs
- Beveled two-tone wall blocks and alternating floor checker drawn cell by cell
- Gradient crates with cross-brace strokes, drop shadows and an amber on-pad halo
- Dashed destination pads under crates and goals
- Eased tween of player and pushed crate between grid cells (~130ms)
- Full-state undo stack plus localStorage star/best persistence

INTENDED INTERACTION MODEL:
Walk with arrows/WASD, shove crates by walking into them, and use undo whenever a crate lands in a corner. Pick any shift from the side log, chase a low move count shown as best, and watch stars accumulate as the yard clears.