Build a ShadowSwap Puzzle Game in HTML5 (Playable & Interactive)

<p class="p1">Prompt:</p>
<p class="p1">Create a playable HTML5 puzzle game called ShadowSwap.</p>
<p class="p1">Rules:</p>
<p class="p1">•Player is a circle</p>
<p class="p1">•Shadow follows the player’s path with a 1–2 second delay</p>
<p class="p1">•Press a key to swap positions with the shadow</p>
<p class="p1">•Obstacles kill the player</p>
<p class="p1">•Goal tile completes the level</p>
<p class="p1">Requirements:</p>
<p class="p1">•Single HTML file (HTML + CSS + JS)</p>
<p class="p1">•Mobile + desktop compatible</p>
<p class="p1">•At least 3 levels</p>
<p class="p1">•Clean animations (no libraries)</p>