修复：解决测试发现的问题

pages/book/detail.vue

@@ -128,7 +128,7 @@
             </text>
           </view>
         </view>
-        <wd-button type="primary" custom-class="buy-btn" @click="handlePurchase">
+        <wd-button type="primary" block @click="handlePurchase">
           {{ $t('bookDetails.buy') }}
         </wd-button>
       </view>
@@ -222,15 +222,12 @@ function initScrollHeight() {
 // 加载书籍详情
 async function loadBookInfo() {
   try {
-    uni.showLoading({ title: t('global.loading') })
     const res = await bookApi.getBookInfo(bookId.value)
-    uni.hideLoading()
     
     if (res.bookInfo) {
       bookInfo.value = res.bookInfo
     }
   } catch (error) {
-    uni.hideLoading()
     console.error('Failed to load book info:', error)
   }
 }
@@ -531,6 +528,7 @@ function goToDetail(id: number) {
       &.buy-full {
         flex: 1;
         padding: 0 30rpx;
+        text-align: center;
       }
     }
   }