Add extra scss file for site variables.

assets/sass/_custom.scss

@@ -1,3 +1,3 @@
 // stylelint-disable color-no-hex, color-named
 
-// Site custom styles
+// Site custom styles. This file loads last.

assets/sass/_extra.scss

@@ -0,0 +1 @@
+// Site extra variables. This file load after init but before everything else.

assets/sass/components/cookieconsent/_cookieconsent.scss

@@ -11,6 +11,7 @@
   text-align: center;
   transform: translateY(100vh);
   transition: all 130ms ease-in;
+  z-index: 99;
 
   a {
     color: inherit;

assets/sass/styles.scss

@@ -14,6 +14,10 @@
   }
 }
 
+// Site specific variables.
+
+@import 'extra';
+
 // Ensure fonts get loaded first to minimize front-end performance impact.
 
 @import 'fonts';