diff --git a/source/css/_common/outline/header/image.styl b/source/css/_common/outline/header/image.styl
index 155e9da..b9863db 100644
--- a/source/css/_common/outline/header/image.styl
+++ b/source/css/_common/outline/header/image.styl
@@ -8,7 +8,9 @@
   min-height: 25rem;
   z-index: -9;
   background-color: #363636;
-
+  content-visibility: auto;
+  contain-intrinsic-size: 100vw 70vh;
+  
   img {
     width: 100%;
     height: 100%;
diff --git a/source/css/_common/outline/header/waves.styl b/source/css/_common/outline/header/waves.styl
index 9902aaa..62bfb34 100644
--- a/source/css/_common/outline/header/waves.styl
+++ b/source/css/_common/outline/header/waves.styl
@@ -5,9 +5,12 @@
   min-height: 3.125rem;
   max-height: 9.375rem;
   position:relative;
+  content-visibility: auto;
+  contain-intrinsic-size: 100vw 15vh;
 
   +mobile() {
     height: 10vh;
+    contain-intrinsic-size: 100vw 10vh;
   }
 }
 /* Animation */