Fix body height

Author: zuck

assets/css/main.css

@@ -12,7 +12,7 @@ body {
   display: flex;
   flex-direction: column;
   width: 100vw;
-  height: 100vh;
+  min-height: 100vh;
   background-image: url('../images/grass.jpg');
   background-position: center center;
   background-attachment: fixed;