Use classic three.js global build instead of ES module import map

index.html

@@ -72,12 +72,8 @@
   <div class="stage" id="stage"></div>
   <p class="hint">나무를 드래그해서 흔들어 보세요 🍎</p>
 
-<script type="importmap">
-{ "imports": { "three": "./vendor/three.module.min.js" } }
-</script>
-<script type="module">
-import * as THREE from "three";
-
+<script src="./vendor/three.min.js"></script>
+<script>
 const stage = document.getElementById('stage');
 
 // ---------- renderer / scene / camera ----------