diff --git a/public/css/nimforum.scss b/public/css/nimforum.scss
index 98b4a04..ead7b0e 100644
--- a/public/css/nimforum.scss
+++ b/public/css/nimforum.scss
@@ -214,17 +214,7 @@ $threads-meta-color: #545d70;
   }
 }
 
-.triangle {
-  // TODO: Abstract this into a "category" class.
-  width: 0;
-  height: 0;
-  border-left: 0.3rem solid transparent;
-  border-right: 0.3rem solid transparent;
-  border-bottom: 0.6rem solid #98c766;
-  display: inline-block;
-}
-
-.square {
+.category-color {
   width: 0;
   height: 0;
   border: 0.3rem solid #98c766;
diff --git a/src/frontend/category.nim b/src/frontend/category.nim
index 1d18c97..de2d248 100644
--- a/src/frontend/category.nim
+++ b/src/frontend/category.nim
@@ -24,7 +24,7 @@ when defined(js):
         tdiv(class="category",
              title=category.description,
              "data-color"="#" & category.color):
-          tdiv(class="square",
+          tdiv(class="category-color",
                style=style(
                  (StyleAttr.border,
                   kstring"0.3rem solid #" & category.color)