Pull request #1579: REPORT-43230 ie下不支持focus-within 写在一起会有兼容性问题

Merge in VISUAL/fineui from ~ALAN/fineui:master to master

* commit '938a12025db9e201a5a6605ca6e1285b1742e509':
  补充注释
  fix: REPORT-43230 ie下不支持focus-within 写在一起会有兼容性问题

src/less/core/utils/common.less

@@ -42,7 +42,11 @@ textarea {
 }
 
 .bi-focus-shadow {
-  &:focus-within, &:focus, &:hover {
+  &:focus, &:hover {
+    border-color: @color-bi-border-highlight;
+  }
+  // ie下不支持focus-within， 和上面写在一起会导致ie下:hover不生效
+  &:focus-within{
     border-color: @color-bi-border-highlight;
   }
   &.disabled {