Change path to background image (#7)

Author: shalingams

docs/stylesheets/extra.css

@@ -7,7 +7,7 @@
        background-image: url('/assets/background2.jpg');
 */
 body {
-    background-image: url('/assets/background.png');
+    background-image: url('../assets/background.png');
     background-size: cover;
     background-repeat: no-repeat;
     background-position: center center;
@@ -251,4 +251,4 @@ body {
     .datu-hero {
         padding: 2rem 0.5rem 1.5rem 0.5rem; /* Hero padding mobile */
     }
-}
+}