前端展示优化，选择的时候展示为绿色按钮

src/views/vehicle/index.vue

@@ -46,7 +46,8 @@
                   <el-tag :type="!vehicle.online ? 'info' : 'success'" style="padding-left: 0; padding-right: 0">
                     {{ vehicle.vin }}
                   </el-tag>
-                  <el-button style="float: right;" @click="checkVin = vehicle.vin" size="mini" :disabled="!vehicle.online">选择</el-button>
+                  <el-button style="float: right;" :type="checkVin === vehicle.vin ? 'success' : ''"
+                             @click="checkVin = vehicle.vin" size="mini" :disabled="!vehicle.online">{{checkVin === vehicle.vin ? "已选择" : "选择"}}</el-button>
                   <span style="float: right; color: rgba(255,255,255,0)">|</span>
                   <el-button v-if="!vehicle.online" style="float: right;" size="mini" @click="clientInit(vehicle.vin)">
                     上线
@@ -308,6 +309,8 @@ export default {
      */
     vehicleUnifiedOffline(){
       unifiedOffline().then(response => {
+        // 一键离线清空车辆选择
+        this.checkVin = null;
         this.$notify({
           title: '操作提示',
           message: response.msg,