style(theme): 统一使用主题颜色变量替换硬编码颜色值

将多处硬编码的颜色值替换为主题颜色变量，提高代码可维护性
更新活动封面页的背景高度以适应新的底部区域高度
更新默认海报图片

@@ -11,7 +11,7 @@
     top: 0;
     left: 0;
     width: 100vw;
-    height: calc(100vh - 100rpx); // 减去底部区域的高度，确保背景图不被遮挡
+    height: calc(100vh - 300rpx); // 减去底部区域的高度，确保背景图不被遮挡
     object-fit: cover;
     object-position: top center;
     z-index: 1;

 <!--
  * @Date: 2022-09-19 14:11:06
  * @LastEditors: hookehuyr hookehuyr@gmail.com
- * @LastEditTime: 2025-09-07 11:09:26
+ * @LastEditTime: 2025-09-11 10:27:08
  * @FilePath: /lls_program/src/pages/ActivitiesCover/index.vue
  * @Description: 活动海报页面 - 展示活动信息并处理定位授权
 -->
@@ -117,7 +117,7 @@
               @click="onLocationConfirm"
               type="primary"
               size="normal"
-              color="#007AFF"
+              :color="THEME_COLORS.PRIMARY"
               block
             >
               同意授权
@@ -139,9 +139,11 @@ import ShareButton from '../../components/ShareButton/index.vue'
 // 接口信息
 import { getMyFamiliesAPI } from '@/api/family'
 import { handleSharePageAuth, addShareFlag } from '@/utils/authRedirect'
+// 导入主题颜色
+import { THEME_COLORS } from '@/utils/config';
 
 // 默认海报图
-const defaultPoster = 'https://cdn.ipadbiz.cn/lls_prog/images/welcome_1.png';
+const defaultPoster = 'https://cdn.ipadbiz.cn/lls_prog/images/welcome_3.jpg';
 /**
  * 活动海报页面组件
  * 功能：展示活动信息、处理定位授权、跳转到活动页面

@@ -66,7 +66,7 @@
 
         <!-- Save Button -->
         <view class="fixed bottom-0 left-0 right-0 p-4 bg-white border-t border-gray-100">
-            <nut-button type="primary" size="large" :color="isFormValid ? '#4A90E2' : '#D8D8D8'" block @click="handleSave" :disabled="!isFormValid">保存</nut-button>
+            <nut-button type="primary" size="large" :color="isFormValid ? THEME_COLORS.PRIMARY : '#D8D8D8'" block @click="handleSave" :disabled="!isFormValid">保存</nut-button>
         </view>
 
         <!-- Popups -->
@@ -114,6 +114,8 @@ import BASE_URL from '@/utils/config';
 const defaultAvatar = 'https://cdn.ipadbiz.cn/mlaj/images/icon_1.jpeg'
 // 获取接口信息
 import { updateUserProfileAPI } from '@/api/user';
+// 导入主题颜色
+import { THEME_COLORS } from '@/utils/config';
 
 /**
  * @description 表单数据

@@ -66,7 +66,7 @@
 
         <!-- Save Button -->
         <view class="fixed bottom-0 left-0 right-0 p-4 bg-white border-t border-gray-100">
-            <nut-button type="primary" size="large" color="#4A90E2" block @click="handleSave">保存</nut-button>
+            <nut-button type="primary" size="large" :color="THEME_COLORS.PRIMARY" block @click="handleSave">保存</nut-button>
         </view>
 
         <!-- Popups -->
@@ -114,6 +114,8 @@ import BASE_URL from '@/utils/config';
 const defaultAvatar = 'https://cdn.ipadbiz.cn/mlaj/images/icon_1.jpeg'
 // 获取接口信息
 import { getUserProfileAPI, updateUserProfileAPI } from '@/api/user';
+// 导入主题颜色
+import { THEME_COLORS } from '@/utils/config';
 
 /**
  * @description 表单数据