fixed sidebar issue in vuejs#2157 (vuejs#2158)

Author: fayazara

themes/vue/source/css/_sidebar.styl

@@ -21,7 +21,7 @@
     margin-top: .5em
   .sidebar-inner
     width: 260px
-    padding: $content-padding-top + 10px 20px 60px 60px
+    padding: $content-padding-top + 40px 0px 60px 20px
   .version-select
     vertical-align: middle
     margin-left: 5px