Fix post-wrapper-style in sm-devices.

Author: FawzyMokhtar

src/styles/components/_post-wrapper.scss

@@ -2,3 +2,9 @@
   padding: 0 2rem 2rem 2rem;
   margin-top: calc(#{$top-navbar-height} - #{$main-content-top-spacing});
 }
+
+@include screen-max-sm {
+  .post-wrapper {
+    margin-top: $top-navbar-height;
+  }
+}