diff --git a/src/app/globals.css b/src/app/globals.css
index 14d660c..4a4ec19 100644
--- a/src/app/globals.css
+++ b/src/app/globals.css
@@ -554,3 +554,8 @@ img {
 img:hover {
   filter: blur(4px);
 }
+
+/* Mass style: make all buttons background black */
+button, .button, [class*='button'], [class*='btn'] {
+  background-color: #000000;
+}