fix(StudyDetailPage): 移除topWrapper高度计算中的冗余偏移量

在`StudyDetailPage.vue`中，`topWrapper`的高度计算中包含了不必要的30px偏移量，导致布局不准确。移除该偏移量以修复布局问题。

@@ -385,7 +385,7 @@ onMounted(async () => {
             const topWrapper = document.querySelector('.top-wrapper');
             const topWrapper = document.querySelector('.top-wrapper');
             const bottomWrapper = document.querySelector('.bottom-wrapper');
             const bottomWrapper = document.querySelector('.bottom-wrapper');
             if (topWrapper) {
             if (topWrapper) {
-                topWrapperHeight.value = topWrapper.clientHeight + 30 + 'px';
+                topWrapperHeight.value = topWrapper.clientHeight + 'px';
             }
             }
             if (bottomWrapper) {
             if (bottomWrapper) {
                 bottomWrapperHeight.value = bottomWrapper.clientHeight + 'px';
                 bottomWrapperHeight.value = bottomWrapper.clientHeight + 'px';