修改需求

src/components/single-input.vue

@@ -7,7 +7,7 @@
   >
     <el-input
       v-model.trim="ivalue"
-      :maxlength="500"
+      :maxlength="100"
       show-word-limit
       type="textarea"
       placeholder="请输入"

src/view/layout/nav.vue

@@ -1,7 +1,13 @@
 <template>
   <div class="main-layout">
     <div class="header" :class="{ [name]: true }">
-      <el-button :icon="Back" circle type="primary" @click="router.back()" />
+      <el-button
+        :icon="Back"
+        circle
+        type="primary"
+        @click="router.back()"
+        v-if="user || name === 'pano'"
+      />
       <el-dropdown class="avatar" v-if="user">
         <span>
           <el-avatar :src="user.head" />