diff --git a/styles/simple.css b/styles/simple.css
index 8160a826..4b38d96b 100644
--- a/styles/simple.css
+++ b/styles/simple.css
@@ -1753,6 +1753,7 @@ div.horloge-roue div img {
 
 .calendar-boutons-heure .calendar-btn:is(.calendar-lyre,.calendar-vaisseau) img {
   color: hsla(0, 0%, 100%, 0.5);
+  border: none;
   vertical-align: bottom;
   max-width: 1.2em;
   max-height: 1.2em;