Brighter image banner (#13)

Author: Grufoony

_styles/background.scss

@@ -16,6 +16,6 @@
   background-size: cover;
   background-repeat: no-repeat;
   background-position: 50% 50%;
-  opacity: 0.25;
+  opacity: 0.6;
   z-index: -1;
-}
+}