diff --git a/packages/ember-promise-modals/src/components/epm-modal-container.css b/packages/ember-promise-modals/src/components/epm-modal-container.css
index 517ebe49..b2e5af84 100644
--- a/packages/ember-promise-modals/src/components/epm-modal-container.css
+++ b/packages/ember-promise-modals/src/components/epm-modal-container.css
@@ -1,18 +1,20 @@
-:root {
-  /* The named -duration and -delay variables will be lowered to near zero when using the setupPromiseModals test helper  */
-  --epm-animation-backdrop-in-duration: 0.3s;
-  --epm-animation-backdrop-out-duration: 0.18s;
-  --epm-animation-modal-in-duration: 0.3s;
-  --epm-animation-modal-out-duration: 0.18s;
-  --epm-animation-backdrop-in-delay: 0s;
-  --epm-animation-backdrop-out-delay: 0s;
-  --epm-animation-modal-in-delay: 0s;
-  --epm-animation-modal-out-delay: 0s;
-  --epm-animation-backdrop-in: var(--epm-animation-backdrop-in-duration) ease var(--epm-animation-backdrop-in-delay) forwards epm-backdrop-in;
-  --epm-animation-backdrop-out: var(--epm-animation-backdrop-out-duration) ease var(--epm-animation-backdrop-out-delay) forwards epm-backdrop-out;
-  --epm-animation-modal-in: var(--epm-animation-modal-in-duration) ease-out var(--epm-animation-modal-in-delay) forwards epm-modal-in;
-  --epm-animation-modal-out: var(--epm-animation-modal-out-duration) ease-out var(--epm-animation-modal-out-delay) forwards epm-modal-out;
-  --epm-backdrop-background: #2d3748CD;
+@layer ember-promise-modals {
+  :root {
+    /* The named -duration and -delay variables will be lowered to near zero when using the setupPromiseModals test helper  */
+    --epm-animation-backdrop-in-duration: 0.3s;
+    --epm-animation-backdrop-out-duration: 0.18s;
+    --epm-animation-modal-in-duration: 0.3s;
+    --epm-animation-modal-out-duration: 0.18s;
+    --epm-animation-backdrop-in-delay: 0s;
+    --epm-animation-backdrop-out-delay: 0s;
+    --epm-animation-modal-in-delay: 0s;
+    --epm-animation-modal-out-delay: 0s;
+    --epm-animation-backdrop-in: var(--epm-animation-backdrop-in-duration) ease var(--epm-animation-backdrop-in-delay) forwards epm-backdrop-in;
+    --epm-animation-backdrop-out: var(--epm-animation-backdrop-out-duration) ease var(--epm-animation-backdrop-out-delay) forwards epm-backdrop-out;
+    --epm-animation-modal-in: var(--epm-animation-modal-in-duration) ease-out var(--epm-animation-modal-in-delay) forwards epm-modal-in;
+    --epm-animation-modal-out: var(--epm-animation-modal-out-duration) ease-out var(--epm-animation-modal-out-delay) forwards epm-modal-out;
+    --epm-backdrop-background: #2d3748CD;
+  }
 }
 
 @media (prefers-reduced-motion: reduce) {