Add hero

Signed-off-by: Nikolaos Karaolidis <nick@karaolidis.com>

assets/sass/common.scss

@@ -21,3 +21,19 @@ h6 {
   margin: 0;
   font-weight: 500;
 }
+
+figure {
+  margin: 0;
+}
+
+body {
+  margin: 0.5rem;
+  min-height: calc(100vh - 1rem);
+
+  display: flex;
+  flex-direction: column;
+
+  main {
+    flex: 1;
+  }
+}