Adjust box material in instanced demo

examples/webgl_modifier_curve_instanced.html

@@ -51,7 +51,7 @@
 				camera.lookAt( scene.position );
 
 				const boxGeometry = new THREE.BoxBufferGeometry( 0.1, 0.1, 0.1 );
-				const boxMaterial = new THREE.MeshBasicMaterial( 0x99ff99 );
+				const boxMaterial = new THREE.MeshBasicMaterial();
 
 				const curves = [[
 					{ x: 1, y: - 0.5, z: - 1 },