fix(rich-text): 移除全局CSS导入避免影响其他组件样式

- 移除 @tarojs/taro/html.css 全局样式导入
- 在组件 scoped style 中添加完整的富文本样式
- 解决 NavHeader 标题不居中的问题

@@ -26,7 +26,7 @@ import { ref, watch, nextTick } from 'vue'
 import Taro from '@tarojs/taro'
 import Taro from '@tarojs/taro'
 import { $ } from '@tarojs/extend'
 import { $ } from '@tarojs/extend'
 import { useFileOperation } from '@/composables/useFileOperation'
 import { useFileOperation } from '@/composables/useFileOperation'
-import '@tarojs/taro/html.css'
+// 注意：不再导入全局的 @tarojs/taro/html.css，改用 scoped 样式
 
 
 /**
 /**
  * 组件属性
  * 组件属性
@@ -265,10 +265,75 @@ watch(() => props.enableTransform, () => {
 
 
 <style lang="less" scoped>
 <style lang="less" scoped>
 .rich-text-content {
 .rich-text-content {
-  // 继承 Taro HTML 样式
-  :deep(img) {
+  // Taro v-html 基础样式（替代 @tarojs/taro/html.css）
+  :deep(.h5-p) {
+    margin: 16rpx 0;
+  }
+
+  :deep(.h5-img) {
     max-width: 100%;
     max-width: 100%;
     height: auto;
     height: auto;
+    display: block;
+  }
+
+  :deep(h1) {
+    font-size: 48rpx;
+    font-weight: bold;
+    margin: 32rpx 0 16rpx;
+  }
+
+  :deep(h2) {
+    font-size: 40rpx;
+    font-weight: bold;
+    margin: 24rpx 0 12rpx;
+  }
+
+  :deep(h3) {
+    font-size: 36rpx;
+    font-weight: bold;
+    margin: 20rpx 0 12rpx;
+  }
+
+  :deep(h4) {
+    font-size: 32rpx;
+    font-weight: bold;
+    margin: 16rpx 0 8rpx;
+  }
+
+  :deep(p) {
+    font-size: 28rpx;
+    line-height: 1.6;
+    margin: 12rpx 0;
+    color: #333;
+  }
+
+  :deep(ul),
+  :deep(ol) {
+    padding-left: 48rpx;
+    margin: 16rpx 0;
+  }
+
+  :deep(li) {
+    font-size: 28rpx;
+    line-height: 1.6;
+    margin: 8rpx 0;
+  }
+
+  :deep(strong) {
+    font-weight: bold;
+  }
+
+  :deep(em) {
+    font-style: italic;
+  }
+
+  :deep(a) {
+    color: #1989fa;
+    text-decoration: underline;
+  }
+
+  :deep(span) {
+    font-size: 28rpx;
   }
   }
 
 
   // 文件链接样式
   // 文件链接样式