style(UI): 统一卡片样式并增强视觉效果

为所有页面卡片添加 enhanced-card 类，实现统一视觉风格
添加卡片悬停动画、顶部装饰条和状态变化效果
优化状态标签、按钮和详情布局的样式

index.php

@@ -487,7 +487,7 @@ $packages_json = json_encode(array_map(function($package) {
                     }
                 </style>
                 
-                <div class="calendar" id="calendarContainer">
+                <div class="calendar enhanced-card" id="calendarContainer">
                     <!-- 日期将通过JavaScript动态生成 -->
                 </div>
                 
@@ -667,7 +667,7 @@ $packages_json = json_encode(array_map(function($package) {
                     }
                 </style>
                 
-                <div class="time-slots" id="timeSlots" style="display: none;">
+                <div class="time-slots enhanced-card" id="timeSlots" style="display: none;">
                     <h3>🕐 选择时间段</h3>
                     <div class="quick-duration">
                         <span>快捷时长：</span>
@@ -688,13 +688,13 @@ $packages_json = json_encode(array_map(function($package) {
                 </div>
                 
                 <!-- 预约详情显示区域 -->
-                <div id="bookingDetails" class="booking-details" style="display: none;">
+                <div id="bookingDetails" class="booking-details enhanced-card" style="display: none;">
                     <h3 id="detailsDateTitle"></h3>
                     <div id="bookingDetailsContent"></div>
                 </div>
             </div>
 
-            <div class="booking-form-section">
+            <div class="booking-form-section enhanced-card">
                 <h2>📋 预约信息</h2>
                 <form method="POST" class="form" id="bookingForm">
                     <div class="form-row">