first responsive adjustments done

Natours/starter/sass/layout/_grid.scss

@@ -4,6 +4,15 @@
 
     &:not(:last-child) {
         margin-bottom: $gutter-vertical;
+
+        @include respond(tab-port) {
+          margin-bottom: $gutter-vertical-small;
+        }
+    }
+
+    @include respond(tab-port) {
+      max-width: 50rem;
+      padding: 0 3rem;
     }
 
     @include clearfix;
@@ -13,7 +22,15 @@
         float: left;
 
         &:not(:last-child) {
-            margin-right: $gutter-horizontal;
+          margin-right: $gutter-horizontal;
+          @include respond(tab-port) {
+            margin-right: 0;
+            margin-bottom: $gutter-vertical-small;
+          }
+        }
+
+        @include respond(tab-port) {
+          width: 100% !important;
         }
     }
 
@@ -40,4 +57,4 @@
     .col-3-of-4 {
         width: calc(3 * ((100% - 3 * #{$gutter-horizontal}) / 4) + 2 * #{$gutter-horizontal});
     }
-}
+}