diff --git a/.changeset/rich-crews-wonder.md b/.changeset/rich-crews-wonder.md
new file mode 100644
index 000000000..67aaf1cb8
--- /dev/null
+++ b/.changeset/rich-crews-wonder.md
@@ -0,0 +1,5 @@
+---
+'@primer/primitives': patch
+---
+
+Add ::backdrop to css
diff --git a/src/platforms/css.ts b/src/platforms/css.ts
index b58005ea4..652abfc40 100644
--- a/src/platforms/css.ts
+++ b/src/platforms/css.ts
@@ -10,9 +10,9 @@ const getCssSelectors = (outputFile: string): {selector: string; selectorLight:
   const mode = outputBasename.substring(0, 4) === 'dark' ? 'dark' : 'light'
 
   return {
-    selector: `[data-color-mode="${mode}"][data-${mode}-theme="${themeName}"]`,
-    selectorLight: `[data-color-mode="auto"][data-light-theme="${themeName}"]`,
-    selectorDark: `[data-color-mode="auto"][data-dark-theme="${themeName}"]`,
+    selector: `[data-color-mode="${mode}"][data-${mode}-theme="${themeName}"], [data-color-mode="${mode}"][data-${mode}-theme="${themeName}"] ::backdrop`,
+    selectorLight: `[data-color-mode="auto"][data-light-theme="${themeName}"], [data-color-mode="auto"][data-light-theme="${themeName}"] ::backdrop`,
+    selectorDark: `[data-color-mode="auto"][data-dark-theme="${themeName}"], [data-color-mode="auto"][data-dark-theme="${themeName}"] ::backdrop`,
   }
 }