fix css

my-blog/templates/post-simple.html

@@ -16,7 +16,7 @@
             <div class="article-actions">
                 {% if post.markdown_url %}
                 <a href="{{ post.markdown_url }}" class="action-btn markdown-btn" title="View Markdown">
-                    📝 Markdown
+                    .md
                 </a>
                 {% endif %}
                 {% if post.translation_url %}