docs(overlay): 增加修改遮罩样式的说明

src/packages/__VUE/overlay/doc.en-US.md

@@ -47,6 +47,8 @@ app.use(OverLay);
 
 ### Mask style
 
+It can be set through `overlay-style`
+
 :::demo
 
 ```html

src/packages/__VUE/overlay/doc.md

@@ -46,6 +46,8 @@ app.use(OverLay);
 
 ### 遮罩样式
 
+可以通过 `overlay-style` 进行设置
+
 :::demo
 
 ```html