diff --git a/snippets/Alert.md b/snippets/Alert.md
index 9daaaf42c..a3832c476 100644
--- a/snippets/Alert.md
+++ b/snippets/Alert.md
@@ -60,7 +60,7 @@ Renders an alert component with `type` prop.
   font-size: 16px;
 }
 
-.alert .close:after {
+.alert .close::after {
   content: 'x';
 }
 ```
diff --git a/snippets/TreeView.md b/snippets/TreeView.md
index 0d13cf359..a10ddbcfb 100644
--- a/snippets/TreeView.md
+++ b/snippets/TreeView.md
@@ -26,7 +26,7 @@ Renders a tree view of a JSON object or array with collapsible content.
   margin-left: 16px;
 }
 
-div.tree-element:before {
+div.tree-element::before {
   content: '';
   position: absolute;
   top: 24px;