1

src/App.vue

@@ -101,6 +101,7 @@ export default {
   justify-content: space-between;
   font-size: 16px;
   line-height: 24px;
+  z-index: 3;
   :nth-child(1) {
     margin-right: 8px;
   }

src/views/courseView.vue

@@ -451,7 +451,7 @@ export default {
       background: #fff;
       position: fixed;
       left: 0;
-      z-index: 1;
+      z-index: 2;
     }
     .content-tree-full {
       position: fixed !important;

src/views/courseWare.vue

@@ -475,7 +475,7 @@ export default {
       background: #fff;
       position: fixed;
       left: 0;
-      z-index: 1;
+      z-index: 2;
     }
     .content-tree-full {
       position: fixed !important;