原本的3D模型顏色是這樣棕色
但放入html裡變成紅色

試問有無方法解決此問題

    <script src="three.js"></script>
    <script type="module" src="GLTFLoader.js"></script>
    <script type="module">
      import { GLTFLoader } from "./GLTFLoader.js";

      var scene = new THREE.Scene();

      var camera = new THREE.PerspectiveCamera(
        15,
        window.innerWidth / window.innerHeight,
        0.01,
        1000
      );
      var renderer = new THREE.WebGLRenderer();
      renderer.setSize(700, 450);
      document.getElementById('3D').appendChild(renderer.domElement);
      /*document.body.appendChild(renderer.domElement);*/

      var loader = new GLTFLoader();

      var obj;
      loader.load("scene.gltf", function (gltf) {
        obj = gltf.scene;
        scene.add(gltf.scene);
      });
      scene.background = new THREE.Color(0x999999);
      var light = new THREE.HemisphereLight(0xffffff, 0x000000, 30);//(天空的反光颜色,地面的反光颜色,光的强度);
      scene.add(light);
      camera.position.set(0, 2.5, 45);
      function animate() {
        requestAnimationFrame(animate);
        obj.rotation.y += 0.01;
        renderer.render(scene, camera);
      }
      animate();
    </script>