diff --git a/app/javascript/stylesheets/components/Board.scss b/app/javascript/stylesheets/components/Board.scss
index bae445c5..19ceb528 100644
--- a/app/javascript/stylesheets/components/Board.scss
+++ b/app/javascript/stylesheets/components/Board.scss
@@ -16,7 +16,7 @@
     }
   }
 
-  @media (max-width: 800px) {
+  @include media-breakpoint-down(sm) {
     flex-direction: column;
 
     .sidebar {
@@ -24,10 +24,10 @@
       width: 100%;
       top: 0;
 
-      .sidebarBox {
-        width: 100%;
-      }
+      .sidebarBox { width: 100%; }
     }
+
+    .postList { width: 100%; }
   }
 
   .newBoardContainer {
diff --git a/app/javascript/stylesheets/components/Roadmap.scss b/app/javascript/stylesheets/components/Roadmap.scss
index 6e88103b..33384c8a 100644
--- a/app/javascript/stylesheets/components/Roadmap.scss
+++ b/app/javascript/stylesheets/components/Roadmap.scss
@@ -13,7 +13,7 @@
     width: 32%;
     background-color: $astuto-grey;
 
-    @media (max-width: 800px) {
+    @include media-breakpoint-down(sm) {
       width: 100%;
     }
   }
diff --git a/app/views/layouts/_header.html.erb b/app/views/layouts/_header.html.erb
index 596a4129..f6a63b60 100644
--- a/app/views/layouts/_header.html.erb
+++ b/app/views/layouts/_header.html.erb
@@ -1,4 +1,4 @@
-<nav class="navbar navbar-expand-lg navbar-light">
+<nav class="navbar navbar-expand-md navbar-light">
   <div class="container">
     <%= link_to 'Astuto', root_path, class: 'navbar-brand' %>
     <button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarSupportedContent" aria-controls="navbarSupportedContent" aria-expanded="false" aria-label="Toggle navigation">