diff --git a/assets/index.less b/assets/index.less
index 1eccdd4..65af1ec 100644
--- a/assets/index.less
+++ b/assets/index.less
@@ -72,7 +72,7 @@
 
   .@{checkboxInnerPrefixCls} {
     border-color: #3dbcf6;
-    background-color: #3dbcf6;
+    box-shadow: inset 0 0 0 16px #3dbcf6;
 
     &:after {
       transform: rotate(45deg);