add class for mark buttons

boards/static/css/md/base_page.css

@@ -189,6 +189,11 b' blockquote {'
     background-color: #442222;
 }
 
+.mark_btn {
+    padding: 2px 4px;
+    border: 1px solid;
+}
+
 .quote {
     color: #92cf38;
     font-style: italic;