修改预览图标大小

src/components/pages/course.vue

@@ -216,7 +216,7 @@
             <div class="three_bottom">
 							<el-tooltip effect="dark" content="预览" placement="top">
     					  <div class="t_b_Item" @click="get(item)">
-									<img src="../../assets/icon/course/lookeye.svg">
+									<img style="height: 90%;width: 90%;" src="../../assets/icon/course/lookeye.svg">
 								</div>
     					</el-tooltip>