Changes sites' main content background color from white to #F5F5F5

- adds <main> tag to apps layout gives it class .main & bulma class .has-background-light
- gives .main padding-bottom of 5rem
- and removed margin top of 5rem from footer so as to get rid of white space between footer and main

Author: JackieBinya

src/App.vue

@@ -112,6 +112,9 @@ export default {
         color: #2c3e50;
         counter-reset: step-counter;
     }
+    .main {
+        padding-bottom: 5rem;
+    }
     #site-container {
         padding: 0.75rem;
     }