diff --git a/addons/website/static/src/scss/website.backend.scss b/addons/website/static/src/scss/website.backend.scss
index 5bb145b0596..a3ec2034d62 100644
--- a/addons/website/static/src/scss/website.backend.scss
+++ b/addons/website/static/src/scss/website.backend.scss
@@ -427,8 +427,7 @@
 
 
 .o_theme_install_loader_container {
-    background-color: $o-shadow-color;
-    opacity: 0.95;
+    background-color: rgba($o-shadow-color, .9);
     pointer-events: all;
 }
 .o_theme_install_loader {