posts: fix rare bug with first post.

Fix a rare bug that occurs once per year that causes post 1 to appear
insufficiently festive.

app/helpers/posts_helper.rb

@@ -41,4 +41,8 @@ module PostsHelper
       source
     end
   end
+
+  def is_danbirthday?(post)
+    post.id == 1 && post.created_at.strftime("%m-%d") == Time.zone.today.strftime("%m-%d")
+  end
 end

app/javascript/src/styles/specific/posts.scss

@@ -159,6 +159,16 @@ div#c-posts {
 
     .image-container {
       margin: 1em 0 0.5em;
+
+      &.danbirthday::before {
+        content: "";
+        position: absolute;
+        left: 33%;
+        top: -16%;
+        width: 100%;
+        height: 100%;
+        background: top left/20% no-repeat url(../../../../../public/images/danbirthday.png);
+      }
     }
 
     #favlist {

app/views/posts/show.html.erb

@@ -44,7 +44,7 @@
 
   <%= render "posts/partials/show/notices", :post => @post %>
 
-  <%= content_tag(:section, class: "image-container note-container", **PostPreviewComponent.new(post: @post).data_attributes) do -%>
+  <%= tag.section class: ["image-container", "note-container", ("danbirthday" if is_danbirthday?(@post))], **PostPreviewComponent.new(post: @post).data_attributes do -%>
     <%= render "posts/partials/show/embedded", post: @post %>
     <div id="note-preview"></div>
   <% end -%>