```

feat(LearningSystem): 添加展开按钮样式类和调整高度

- 为学习系统页面的展开按钮容器添加 isShowBtn 样式类
- 调整类型列表的高度从 50px 到 52.17px 以适配内容
- 为 isShowBtn 类添加行高样式 line-height: 31px
```

src/pages/LearningSystem/LearningSystem.vue

@@ -39,7 +39,7 @@
               {{item.dictLabel}}
             </div>
           </div>
-          <div>
+          <div class="isShowBtn">
             <el-link type="primary" v-if="!isShowStudyStage" @click="isShowStudyStage = true;">
               {{$t('common.expand')}}<el-icon><ArrowDown /></el-icon>
             </el-link>
@@ -63,7 +63,7 @@
               {{item.dictLabel}}
             </div>
           </div>
-          <div>
+          <div class="isShowBtn">
             <el-link type="primary" v-if="!isShowCourseCategory" @click="isShowCourseCategory = true;">
               {{$t('common.expand')}}<el-icon><ArrowDown /></el-icon>
             </el-link>
@@ -87,7 +87,7 @@
               {{item.dictLabel}}
             </div>
           </div>
-          <div>
+          <div class="isShowBtn">
             <el-link type="primary" v-if="!isShowSkillTag" @click="isShowSkillTag = true;">
               {{$t('common.expand')}}<el-icon><ArrowDown /></el-icon>
             </el-link>
@@ -282,10 +282,10 @@
     padding: 0 12px 0;
     .typeList{
       padding: 9px 0;
-      height: 50px;
+      height: 52.17px;
       overflow: hidden;
       &.isShow{
-        min-height: 50px;
+        min-height: 52.17px;
         height: auto;
       }
       &.typeborder{
@@ -308,6 +308,9 @@
           font-weight: 600;
         }
       }
+      .isShowBtn{
+        line-height: 31px;
+      }
     }
   }
   .course-item{