fix:修复学院管理页header层级问题

src/modules/root/CollegeManagePage.less

@@ -13,6 +13,7 @@
     display: flex;
     display: flex;
     justify-content: center;
     justify-content: center;
     background: #fff;
     background: #fff;
+    z-index: 999;
     .box {
     .box {
       height: 60px;
       height: 60px;
       width: 1280px;
       width: 1280px;