diff --git a/resources/css/components/tooltip.css b/resources/css/components/tooltip.css
index 5c00df6a..31398847 100644
--- a/resources/css/components/tooltip.css
+++ b/resources/css/components/tooltip.css
@@ -25,7 +25,7 @@
         margin: 0;
         max-inline-size: 200px;
         overflow: visible;
-        border: 0;
+        border-width: 0;
         border-radius: var(--md-sys-shape-corner-xs);
         padding-block: var(--md-sys-measurement-space50);
         padding-inline: var(--md-sys-measurement-space100);