blur content when the menu is open

_sass/klise/_base.scss

@@ -271,6 +271,11 @@ blockquote {
     max-width: calc(#{$narrow-size} - (#{$spacing-full}));
     padding-right: $spacing-full - 10;
     padding-left: $spacing-full - 10;
+
+    &.trigger-wrapper {
+      animation: 0.2s ease-in forwards blur;
+      -webkit-animation: 0.2s ease-in forwards blur;
+    }
   }
 }
 

_sass/klise/_miscellaneous.scss

@@ -5,7 +5,18 @@
   }
 
   100% {
-    opacity: 0.99;
+    opacity: 0.8;
+  }
+}
+
+// Animation blur
+@keyframes blur {
+  0% {
+    filter: blur(0px);
+  }
+
+  100% {
+    filter: blur(4px);
   }
 }