design: gap 수치 수정

frontend/src/pages/LearningLectureDetailPage/LearningLectureDetailPage.jsx

@@ -20,7 +20,7 @@ export default function LearningLectureDetailPage() {
     ],
   };
   return (
-    <main className={styles.previews}>
+    <section className={styles.previews}>
       <ArticlePreview
         to="notice"
         title="공지사항"
@@ -32,6 +32,6 @@ export default function LearningLectureDetailPage() {
         contents={questions}
       />
       <ArticlePreview title="커리큘럼" />
-    </main>
+    </section>
   );
 }

frontend/src/pages/LearningLectureDetailPage/LearningLectureDetailPage.module.css

@@ -1,5 +1,5 @@
 .previews {
   display: flex;
   flex-direction: column;
-  gap: 40px;
+  gap: 20px;
 }