add ts file

src/loading.js

@@ -9,7 +9,11 @@ export default class Loading {
   init() {
     const { option, refs: { $loading } } = this.art;
     if (option.loading) {
-      $loading.insertAdjacentHTML('beforeend', option.loading);
+      if (option.loading instanceof Element) {
+        $loading.appendChild(option.loading);
+      } else {
+        $loading.insertAdjacentHTML('beforeend', option.loading);
+      }
     } else {
       $loading.appendChild(Icons.loading);
     }

src/utils/verification.js

@@ -67,7 +67,7 @@ export default function verification(option) {
   );
 
   errorHandle(
-    typeof option.loading === 'string',
+    typeof option.loading === 'string' || option.loading instanceof Element,
     `'loading' option require 'string' type, but got '${typeof option.loading}'.`
   );