(vue)人工智能，区分对话框各自内容区域样式

效果：

思路：
1.一行里包含 对方头像、内容、我方头像 三部分
2.根据消息数组的下标，确定是我方消息还是对方消息（偶数我方，奇数对方）
3.根据奇偶数显示对应头像，添加对应class。

<!-- 对话框 --> 
<div
  v-for="(item, index) in chatList"
  class="chat-item"
  :class="[index%2===1 ? 'question' :'answer']"
  :key="index"
>
  <!-- 1.对方头像 --> 
  <div class="header-img-wrapper">
    <el-image v-if="index%2===1" :src="otherImg" :fit="fit" class="header-img"></el-image>
  </div>
  <!-- 2.内容 --> 
  <div class="content">
    <div class="content-width">{{ item.content }}</div>
    <div class="indicator"></div>  <!-- 小箭头 --> 
  </div>
  <!-- 3.我方头像 --> 
  <div class="header-img-wrapper">
    <el-image v-if="index%2===0" :src="meImg" :fit="fit" class="header-img"></el-image>
  </div>
</div>

css

.chat-main {
  width: 90%;
  height: 67%;
  padding: 20px;
  margin: 0 auto;
  overflow-y: auto; 
  // 单条信息
  .chat-item {
    display: flex;
    justify-content: space-between;
    text-align: left;
    // 头像
    .header-img-wrapper {
      width: 60px;
      height: 60px;
      .header-img {
        width: 60px;
        height: 60px;
        border-radius: 4px;
      }
    }
    // 内容
    .content {
      flex: 1;
      font-size: 16px;
      color: #ffffff;
      margin: 0 30px;
      position: relative;
      border-radius: 4px;
      padding: 16px 20px;
      line-height: 23px; 
    } 
  }
  
  // 重点样式 //
    
  .chat-item.question .content {
    background: rgba(31, 159, 191, 0.9);
    border: 1px solid #74eaff;
    box-shadow: 0 0 20px -8px #74eaff, 0 0 20px -8px #74eaff,
      0 0 20px -8px #74eaff, 0 0 20px -8px #74eaff, 0 0 20px -8px #74eaff;
  }
  .chat-item.question .indicator {
    width: 0;
    height: 0;
    border-top: 10px solid transparent;
    border-bottom: 10px solid transparent;
    border-right: 10px solid rgba(31, 159, 191, 0.9);
    position: absolute;
    left: -8px;
    top: 16px;
    box-shadow: 0 0 20px -8px #74eaff, 0 0 20px -8px #74eaff,
      0 0 20px -8px #74eaff, 0 0 20px -8px #74eaff, 0 0 20px -8px #74eaff;
    background-image: url("../assets/images/middle/otherBg.png");
    background-size: 100% 100%;
  }

  .chat-item.answer .content {
    background: rgba(0, 22, 87, 0.9);
    border: 1px solid #74eaff;
    box-shadow: 0 0 20px -8px #74eaff, 0 0 20px -8px #74eaff,
      0 0 20px -8px #74eaff, 0 0 20px -8px #74eaff, 0 0 20px -8px #74eaff;
  }

  .chat-item.answer .indicator {
    width: 0;
    height: 0;
    border-top: 10px solid transparent;
    border-bottom: 10px solid transparent;
    border-left: 10px solid rgba(0, 22, 87, 0.9);
    position: absolute;
    right: -8px;
    top: 16px;
    box-shadow: 0 0 20px -8px #74eaff, 0 0 20px -8px #74eaff,
      0 0 20px -8px #74eaff, 0 0 20px -8px #74eaff, 0 0 20px -8px #74eaff;
  }

  .chat-item:not(:first-child) {
    margin-top: 38px;
  }
}