导航栏位置调整

src/stage/index/style/CourseScene.less

@@ -53,7 +53,7 @@
 			display: inline-block;
 			width: 8rem;
 			height: 100%;
-			margin-left: 2.3rem;
+			margin-left: 2.1rem;
 
 			.nav-item {
 				position: relative;