Style comment form

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

app/assets/stylesheets/generic/markdown_area.scss

@@ -65,8 +65,11 @@
   position: relative;
 }
 
-.md-header ul {
+.md-header {
+  ul {
     float: left;
+    margin-bottom: 1px;
+  }
 }
 
 .referenced-users {

app/assets/stylesheets/generic/zen.scss

@@ -4,7 +4,7 @@
   }
 
   .zen-enter-link {
-    color: #888;
+    color: $gl-gray;
     position: absolute;
     top: 0px;
     right: 4px;
@@ -13,7 +13,7 @@
 
   .zen-leave-link {
     display: none;
-    color: #888;
+    color: $gl-text-color;
     position: absolute;
     top: 10px;
     right: 10px;

app/assets/stylesheets/pages/issuable.scss

@@ -25,8 +25,6 @@
 }
 
 .issuable-context-title {
-  font-size: 14px;
-  line-height: 1.4;
   margin-bottom: 5px;
 
   .avatar {
@@ -34,18 +32,12 @@
   }
 
   label {
-    color: #666;
+    color: $gl-gray;
     font-weight: normal;
     margin-right: 4px;
   }
 }
 
-.issuable-affix .context {
-  font-size: 13px;
-
-  .btn { font-size: 13px; }
-}
-
 .project-issuable-filter {
   .controls {
     float: right;

app/views/projects/_md_preview.html.haml

 .md-area
   .md-header.clearfix
-    %ul.nav.nav-tabs
+    %ul.center-top-menu
       %li.active
         = link_to '#md-write-holder', class: 'js-md-write-button', tabindex: '-1' do
           Write