feat: 页面级入场动画 (fade + translateY) 应用到 5 个页面

app.wxss

@@ -94,3 +94,13 @@ image {
   color: var(--text);
   margin-bottom: 20rpx;
 }
+
+/* ---- page-level transition ---- */
+.page-enter {
+  animation: pageIn 0.35s cubic-bezier(0.2, 0, 0.2, 1) both;
+}
+
+@keyframes pageIn {
+  from { opacity: 0; transform: translateY(20rpx); }
+  to   { opacity: 1; transform: translateY(0); }
+}

pages/index/index.wxml

@@ -1,4 +1,4 @@
-<view class="container" style="{{themeStyle}}">
+<view class="container page-enter" style="{{themeStyle}}">
 
   <!-- 顶部问候 -->
   <view class="greeting-row">

pages/leaderboard/leaderboard.wxml

@@ -1,4 +1,4 @@
-<view class="container" style="{{themeStyle}}">
+<view class="container page-enter" style="{{themeStyle}}">
   <!-- Period tabs -->
   <view class="period-tabs">
     <view

pages/records/records.wxml

@@ -1,4 +1,4 @@
-<view class="container" style="{{themeStyle}}">
+<view class="container page-enter" style="{{themeStyle}}">
   <!-- 统计卡片 -->
   <ui-card variant="in">
     <view class="stats">

pages/settings/settings.wxml

@@ -1,4 +1,4 @@
-<view class="container" style="{{themeStyle}}">
+<view class="container page-enter" style="{{themeStyle}}">
   <!-- 个人资料 -->
   <ui-card variant="in">
     <view class="section-header">

pages/timer/timer.wxml

@@ -1,4 +1,4 @@
-<view class="container timer-page" style="{{themeStyle}}">
+<view class="container timer-page page-enter" style="{{themeStyle}}">
 
   <!-- 呼吸引导环 + 进度条 -->
   <view class="ring-wrapper">