fix: 设置多个视图的背景色为透明

Web/src/views/BudgetView.vue

@@ -507,4 +507,9 @@ const handleDelete = (budget) => {
   font-weight: 600;
   font-family: DIN Alternate, system-ui;
 }
+
+/* 设置页面容器背景色 */
+:deep(.van-nav-bar) {
+  background: transparent !important;
+}
 </style>

Web/src/views/CalendarView.vue

@@ -291,6 +291,10 @@ onBeforeUnmount(() => {
 </script>
 
 <style scoped>
+.van-calendar{
+  background: transparent !important;
+}
+
 .calendar-container {
   /* 使用准确的视口高度减去 TabBar 高度（50px）和安全区域 */
   height: calc(var(--vh, 100vh) - 50px - env(safe-area-inset-bottom, 0px));

Web/src/views/StatisticsView.vue

@@ -969,14 +969,14 @@ onBeforeUnmount(() => {
 
 <style scoped>
 .page-container-flex{
-  background-color: var(--van-background-2);
+  background: transparent !important;
 }
 
 .overview-fixed-wrapper {
   position: sticky;
   top: 0;
   z-index: 10;
-  background-color: var(--van-background-2);
+  background: transparent !important;
   padding: 16px 0 1px 0;
   overflow-x: hidden;
 }