Update style.css

docs/assets/css/style.css

@@ -36,6 +36,18 @@ img {
     vertical-align: top;
 }
 
+::-webkit-scrollbar {
+    width: 5px;
+}
+
+::-webkit-scrollbar-thumb {
+    background-color: #666;
+}
+
+::-webkit-scrollbar-thumb:hover {
+    background-color: #ccc;
+}
+
 .header {
     display: flex;
     justify-content: space-between;
@@ -67,7 +79,7 @@ img {
     cursor: pointer;
 }
 
-.header .menus .has-sub-menu:hover .sub-menu{
+.header .menus .has-sub-menu:hover .sub-menu {
     display: block;
 }