修改tip的图标

@@ -21,9 +21,8 @@
         left: 12px;
         width: 0;
         height: 0;
-        border-width: 5px;
         top: -10px;
-        border-style: solid dashed dashed;
-        border-color: transparent transparent #379ed6;
+        border: 5px solid transparent;
+        border-bottom: 5px solid #379ed6;
     }
 }