fix(picker): 解决透传popup的round属性不生效问题 (#3205)

* fix(badge): 解决中文偏上问题

* fix: css 变量更新

* fix: 解决picker设置popup的round属性不生效问题

Author: irisSong

src/packages/picker/picker.scss

@@ -1,7 +1,6 @@
 @import '../popup/popup.scss';
 @import '../pickerview/pickerview.scss';
 .nut-picker {
-  background-color: $color-background-overlay;
   width: 100%;
 
   &-control {