From 30d4d85b3462be4f04e1ea3e562b2f837dd9b7c6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E8=8A=B1=E8=A3=A4=E8=A1=A9?= <panfree23@gmail.com>
Date: Thu, 21 Feb 2019 16:08:22 +0800
Subject: [PATCH] perf[Navbar]: add scroll bar when the subMenu is too long
 (#1619)

---
 src/styles/sidebar.scss | 21 ++++++++++++++++++++-
 1 file changed, 20 insertions(+), 1 deletion(-)

diff --git a/src/styles/sidebar.scss b/src/styles/sidebar.scss
index ce619fd3..96e89be7 100644
--- a/src/styles/sidebar.scss
+++ b/src/styles/sidebar.scss
@@ -170,8 +170,27 @@
   .nest-menu .el-submenu>.el-submenu__title,
   .el-menu-item {
     &:hover {
-      // You can use $subMenuHover
+      // you can use $subMenuHover
       background-color: $menuHover !important;
     }
   }
+
+  // the scroll bar appears when the subMenu is too long
+  >.el-menu--popup {
+    max-height: 100vh;
+    overflow-y: auto;
+
+    &::-webkit-scrollbar-track-piece {
+      background: #d3dce6;
+    }
+
+    &::-webkit-scrollbar {
+      width: 6px;
+    }
+
+    &::-webkit-scrollbar-thumb {
+      background: #99a9bf;
+      border-radius: 20px;
+    }
+  }
 }