Explicitly set colors of banner.

assets/scss/hugo_cookie_consent/style.scss

@@ -1,10 +1,12 @@
 #cookie-banner {
+  color: inherit;
+  background-color: inherit;
   position: fixed;
   top: 2.5rem;
   left: 50%;
   transform: translateX(-50%);
-  width: min(480px, calc(100vw - 2rem));
-  background: #fff;
+  width: calc(100vw - 2rem);
+  max-width: 480px;
   border: 1px solid #e2e2e2;
   border-radius: 12px;
   padding: 1rem 1.25rem;
@@ -37,3 +39,6 @@
   background: #0b913a; color: #fff; border-color: #1a1a1a;
 }
 
+#cookie-decline {
+  background: #272b2e; color: #fff; border-color: #1a1a1a;
+}