Fix .ace_fold arrows

border color will now be applied correctly

dist/nord-polar-night-aurora.rstheme

 
 .ace_fold {
   background-color: #bf616a;
-  border-color: #d8dee9;
+  border: 1px solid #d8dee9 !important;
 }
 
 .ace_indent-guide {

dist/nord-snow-storm.rstheme

 }
 
 .ace_fold {
-  background-color: #bf616a;
-  border-color: #4c566a;
+  background-color: rgba(191, 97, 106, 0.5);
+  border: 1px solid #bf616a !important;
 }
 
 .ace_indent-guide {

dist/oceanic-plus.rstheme

 
 .ace_fold {
   background-color: #EC5f67;
-  border-color: #D8DEE9;
+  border: 1px solid #D8DEE9 !important;
 }
 
 .ace_indent-guide {

dist/solarized-dark.rstheme

 
 .ace_fold {
   background-color: #6c71c4;
-  border-color: #839496;
+  border: 1px solid #839496 !important;
 }
 
 .ace_indent-guide {

dist/solarized-light.rstheme

 
 .ace_fold {
   background-color: #6c71c4;
-  border-color: #657b83;
+  border: 1px solid #657b83 !important;
 }
 
 .ace_indent-guide {

src/nord-snow-storm.scss

 $ui-invisible             : $nord4;
 $ui-indent-guide          : $nord4;
 $ui-debug-background      : lighten($ui-background, 10%);
-$ui-fold-arrows-background: $nord11;
-$ui-fold-arrows-color     : $ui-foreground;
+$ui-fold-arrows-color     : $nord11;
+$ui-fold-arrows-background: transparentize($ui-fold-arrows-color, 0.5);
 
 // rstudio
 $ui-rstudio-background          : darken($ui-background, 2%);

src/rstudio/_rstudio-dark.scss

 }
 .ace_fold {
 	background-color: $ui-fold-arrows-background;
-	border-color: $ui-fold-arrows-color;
+	border: 1px solid $ui-fold-arrows-color !important;
 }
 .ace_indent-guide{
 	border-right: 1px solid $ui-indent_guide;

src/rstudio/_rstudio-light.scss

 }
 .ace_fold {
 	background-color: $ui-fold-arrows-background;
-	border-color: $ui-fold-arrows-color;
+	border: 1px solid $ui-fold-arrows-color !important;
 }
 .ace_indent-guide{
 	border-right: 1px solid $ui-indent_guide;