flex标题居中布局

<div class="title">
     <div class="line"></div>
     <div class="text">优惠信息</div>
     <div class="line"></div>
</div>

.title{
    display: flex;
    width:80%;
    margin:30px auto 24px auto;
  }
.title .line{
    flex: 1;
    position: relative;
    top:-6px;
    border-bottom: 1px solid rgba(255,255,255,0.2);
  }
.title .text{
    font-size:14px;
    padding:0 12px;
  }