fix: 修改悬浮按钮样式

src/components/CustomerServiceFab.vue

@@ -70,7 +70,7 @@ function openHelpCenter() {
 </script>
 
 <template>
-  <wd-fab v-model:active="active" position="right-bottom" direction="top" :custom-style="fabCustomStyle" :expandable="false" :draggable="true">
+  <wd-fab v-model:active="active" position="right-bottom" :z-index="999" direction="top" :custom-style="fabCustomStyle" :expandable="false" :draggable="true">
     <template #trigger>
       <view class="w-80rpx">
         <view class="customer-fab-action mb-12rpx" @click="openCustomerService">