Pull request #2938: KERNEL-12151 按钮水波纹定位不对

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

* commit '8e186f57cf1083c0d70edcc575cf1acba7fcaf1d':
  KERNEL-12151 fix:按钮水波纹定位不对

src/less/base/single/button/button.less

@@ -401,6 +401,10 @@ body .bi-button, #body .bi-button {
 }
 
 .bi-basic-button {
+
+  // 按钮水波纹需要根据按钮根结点定位
+  position: relative;
+
   &.button-common, &.button-success, &.button-warning, &.button-error {
     &:after {
       content: "";