element 点击切换按钮的颜色

   <el-button-group label="时间">
         <el-button  @click="seeHour" :type="buttonhour"  >时</el-button>
         <el-button  @click="seeDay"  :type="buttonday"  >天</el-button>
         <el-button  @click="seeMonth" :type="buttonmonth" >月</el-button>
   </el-button-group>

data() {
    return {
      buttonhour:‘primary‘,
      buttonday:‘‘,
      buttonmonth:‘‘,
}
}

seeHour() {
          this.showDay=false;
          this.showHour=true;
          this.showMonth=false;
          this.buttonhour=‘primary‘;
          this.buttonday=‘‘;
          this.buttonmonth=‘‘;
   },
   seeDay() {
          this.showDay=true;
          this.showHour=false;
          this.showMonth=false;
          this.buttonday=‘primary‘;
          this.buttonhour=‘‘;
          this.buttonmonth=‘‘;
   },
   seeMonth() {
         this.showDay=false;
         this.showHour=false;
         this.showMonth=true;
         this.buttonmonth=‘primary‘;
         this.buttonday=‘‘;
         this.buttonhour=‘‘;
   }