diff --git a/web/static/app.css b/web/static/app.css
index 343ac66..fff1c3a 100644
--- a/web/static/app.css
+++ b/web/static/app.css
@@ -454,4 +454,16 @@ body, .lead-text, .page, .card, .search-input, .input-hero, .textarea-hero,
 /* Inner content padding so the paragraph/button align with the title text */
 .iotd-panel{
   padding:12px 16px;   /* same gutter as other panels */
+}
+
+body.dark-mode {
+  background-color: #0f172a; /* deep navy */
+  color: #e5e7eb; /* light gray text */
+}
+body.dark-mode .card {
+  background-color: #1e293b;
+  border-color: #334155;
+}
+body.dark-mode a {
+  color: #93c5fd; /* soft blue links */
 }
\ No newline at end of file