style(profile): 调整学习课程页面底部间距

style(checkin): 优化打卡卡片图片布局

修改学习课程页面底部间距从30vh增加到80vh以提供更多空间
重构打卡卡片图片布局，使用固定宽高比和更合理的间距

@@ -43,8 +43,10 @@
             <div class="post-media">
                 <!-- Images -->
                 <div v-if="post.images.length" class="post-images">
-                    <van-image width="30%" fit="cover" v-for="(image, index) in post.images" :key="index"
-                        :src="getOptimizedUrl(image)" radius="5" @click="openImagePreview(index)" />
+                    <div class="post-image-item" v-for="(image, index) in post.images" :key="index">
+                        <van-image width="100%" height="100%" fit="cover" :src="getOptimizedUrl(image)" radius="5"
+                            @click="openImagePreview(index)" />
+                    </div>
                 </div>
                 <van-image-preview v-if="post.images.length" v-model:show="showLocalImagePreview" :images="post.images"
                     :start-position="localStartPosition" :show-index="true" />
@@ -253,6 +255,13 @@ defineExpose({
                 display: flex;
                 flex-wrap: wrap;
                 gap: 0.5rem;
+
+                .post-image-item {
+                    width: calc((100% - 1rem) / 3);
+                    aspect-ratio: 1 / 1;
+                    border-radius: 6px;
+                    overflow: hidden;
+                }
             }
 
             .post-video {

@@ -96,7 +96,7 @@
                 </div>
             </div>
 
-            <div style="height: 30vh;"></div>
+            <div style="height: 80vh;"></div>
         </div>
 
         <!-- 打卡弹窗：统一使用 CheckInDialog 组件 -->