diff --git a/layout/archive.njk b/layout/archive.njk
index f8e4d9a..76e1a14 100644
--- a/layout/archive.njk
+++ b/layout/archive.njk
@@ -4,7 +4,7 @@
 
 {% block title %}{{ __('title.archive') }} | {{ title }}{% endblock %}
 
-{% block class %}archive{% endblock %}
+{% block class %}archive posts-collapse{% endblock %}
 
 {% block content %}
 
@@ -12,7 +12,7 @@
   {### ARCHIVE BLOCK ###}
   {#####################}
   <div class="post-block">
-    <div class="posts-collapse">
+    <div class="post-content">
       <div class="collection-title">
         {%- set posts_length = site.posts.length %}
         {%- if posts_length > 210 %}
diff --git a/layout/category.njk b/layout/category.njk
index be7f193..49850fd 100644
--- a/layout/category.njk
+++ b/layout/category.njk
@@ -4,7 +4,7 @@
 
 {% block title %}{{ __('title.category') }}: {{ page.category }} | {{ title }}{% endblock %}
 
-{% block class %}category{% endblock %}
+{% block class %}category posts-collapse{% endblock %}
 
 {% block content %}
 
@@ -12,7 +12,7 @@
   {### CATEGORY BLOCK ###}
   {######################}
   <div class="post-block">
-    <div class="posts-collapse">
+    <div class="post-content">
       <div class="collection-title">
         <h2 class="collection-header">
           {{- page.category }}
diff --git a/layout/tag.njk b/layout/tag.njk
index 6756666..66a6a9e 100644
--- a/layout/tag.njk
+++ b/layout/tag.njk
@@ -4,7 +4,7 @@
 
 {% block title %}{{ __('title.tag') }}: {{ page.tag }} | {{ title }}{% endblock %}
 
-{% block class %}tag{% endblock %}
+{% block class %}tag posts-collapse{% endblock %}
 
 {% block content %}
 
@@ -12,7 +12,7 @@
   {### TAG BLOCK ###}
   {#################}
   <div class="post-block">
-    <div class="posts-collapse">
+    <div class="post-content">
       <div class="collection-title">
         <h2 class="collection-header">
           {{- page.tag }}
diff --git a/source/css/_common/components/post/post-collapse.styl b/source/css/_common/components/post/post-collapse.styl
index 038964c..2a4351c 100644
--- a/source/css/_common/components/post/post-collapse.styl
+++ b/source/css/_common/components/post/post-collapse.styl
@@ -1,4 +1,4 @@
-.posts-collapse {
+.posts-collapse .post-content {
   margin-bottom: $posts-collapse-margin;
   margin-left: $posts-collapse-margin;
   position: relative;
diff --git a/source/css/_common/outline/mobile.styl b/source/css/_common/outline/mobile.styl
index 7e59409..bb14012 100644
--- a/source/css/_common/outline/mobile.styl
+++ b/source/css/_common/outline/mobile.styl
@@ -24,11 +24,6 @@
     padding: $content-mobile-padding 18px $content-mobile-padding !important;
   }
 
-  .posts-collapse {
-    margin-left: 0;
-    margin-right: 0;
-  }
-
   .post-body {
     // For headers narrow width.
     h1, h2, h3, h4, h5, h6 {
diff --git a/source/css/_variables/base.styl b/source/css/_variables/base.styl
index 6db4a24..ffd7c6e 100644
--- a/source/css/_variables/base.styl
+++ b/source/css/_variables/base.styl
@@ -222,7 +222,7 @@ $site-subtitle-color            = $grey-dark;
 // Posts Collpase
 // --------------------------------------------------
 $posts-collapse-margin          = 35px;
-$posts-collapse-margin-mobile   = 0px;
+$posts-collapse-margin-mobile   = 0;
 
 
 // Tag Cloud