Improving back button styling and colour schemes.

www/js/main.js

@@ -138,7 +138,10 @@ $(() => {
       top: '-3rem',
       right: '-3rem'
     }, {
-      duration: 300
+      duration: 300,
+      complete: () => {
+        $('#backbutton').removeAttr('class')
+      }
     })
 
 
@@ -194,7 +197,7 @@ $(() => {
       duration: 300
     })
 
-    $('#backbutton').animate({
+    $('#backbutton').addClass(p).animate({
       top: '2.5rem',
       right: '2.5rem'
     }, {