diff --git a/src/themes/basic/_layout.styl b/src/themes/basic/_layout.styl
index 1e37e4bd4..a38dd93f1 100644
--- a/src/themes/basic/_layout.styl
+++ b/src/themes/basic/_layout.styl
@@ -171,14 +171,13 @@ li input[type='checkbox']
       border-bottom-color #ccc
       border-radius 4px
       box-sizing border-box
-      display none
       max-height calc(100vh - 61px)
       overflow-y auto
       padding 10px 0
       position absolute
       right -15px
       text-align left
-      top 100%
+      top -100vh
       white-space nowrap
 
       li
@@ -198,8 +197,9 @@ li input[type='checkbox']
         &.active
           border-bottom 0
 
+    &:focus-within ul,
     &:hover ul
-      display block
+      top: 100%;
 
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