style: 调整支付页面和组件的样式以改善视觉效果

将 `h-screen` 替换为 `h-full`，并在 `OrdersPage.vue` 中添加渐变背景，以提升支付页面的视觉一致性和美观度。

 <template>
   <!-- 支付成功状态 -->
-  <div v-if="paymentStatus === 'success'" class="h-screen flex flex-col items-center justify-center px-4">
+  <div v-if="paymentStatus === 'success'" class="h-full flex flex-col items-center justify-center px-4">
     <FrostedGlass class="p-6 rounded-xl text-center">
       <div class="w-20 h-20 bg-green-100 rounded-full flex items-center justify-center mx-auto mb-4">
         <svg xmlns="http://www.w3.org/2000/svg" class="h-10 w-10 text-green-500" fill="none" viewBox="0 0 24 24" stroke="currentColor">
@@ -22,7 +22,7 @@
   </div>
 
   <!-- 支付处理中状态 -->
-  <div v-else-if="paymentStatus === 'processing'" class="h-screen flex flex-col items-center justify-center px-4">
+  <div v-else-if="paymentStatus === 'processing'" class="h-full flex flex-col items-center justify-center px-4">
     <FrostedGlass class="p-6 rounded-xl text-center">
       <div class="w-20 h-20 bg-blue-50 rounded-full flex items-center justify-center mx-auto mb-4">
         <div class="w-10 h-10 border-4 border-blue-500 border-t-transparent rounded-full animate-spin"></div>
@@ -33,7 +33,7 @@
   </div>
 
   <!-- 支付失败状态 -->
-  <div v-else-if="paymentStatus === 'failed'" class="h-screen flex flex-col items-center justify-center px-4 sm:px-6 lg:px-8">
+  <div v-else-if="paymentStatus === 'failed'" class="h-full flex flex-col items-center justify-center px-4 sm:px-6 lg:px-8">
     <FrostedGlass class="w-full max-w-sm sm:max-w-md lg:max-w-lg p-6 sm:p-8 rounded-2xl text-center">
       <div class="w-20 h-20 sm:w-24 sm:h-24 bg-red-50 rounded-full flex items-center justify-center mx-auto">
         <svg xmlns="http://www.w3.org/2000/svg" class="h-10 w-10 sm:h-12 sm:w-12 text-red-500" fill="none" viewBox="0 0 24 24" stroke="currentColor">

@@ -166,13 +166,15 @@
       close-icon-position="top-right"
       :style="{ height: '90%' }"
     >
-      <WechatPayment
-        v-if="showPaymentPopup && currentOrder"
-        :order-id="currentOrder.id"
-        @success="handlePaymentSuccess"
-        @failed="handlePaymentFailed"
-        @processing="handlePaymentProcessing"
-      />
+      <div class="bg-gradient-to-r from-green-500/10 to-blue-500/10 h-full">
+        <WechatPayment
+          v-if="showPaymentPopup && currentOrder"
+          :order-id="currentOrder.id"
+          @success="handlePaymentSuccess"
+          @failed="handlePaymentFailed"
+          @processing="handlePaymentProcessing"
+        />
+      </div>
     </van-popup>
   </AppLayout>
 </template>