常见布局

1. 美团网切换城市

按字母选择和他下面的主体内容的样式

.category {
    padding-top: 20px;
    dd {
      cursor: pointer;
      font-size: 15px;
      color: #666;
    }
    .hd {
      margin-bottom: 30px;
      dt {
        font-size: 16px;
        color: #333;
        font-weight: 500;
        display: inline-block;
      }
      dd {
        width: 24px;
        text-align: center;
        margin: 0 6px;
        display: inline-block;
        a {
          color: #41B883;
        }
      }
    }
    .bd {
      display: flex;
      padding: 13px 30px 13px 10px;
      border-radius: 10px;
      &:hover {
        background-color: #F8F8F8;
      }
      dt {
        color: #fff;
        border-radius: 50%;
        background-color: #13D1BE;
        text-align: center;
        width: 40px;
        height: 40px;
        line-height: 40px;
        box-shadow: 0 4px 5px 0 rgba(39, 178, 164, 0.22)
      }
      dd {
        flex: 1;
        a {
          color: #666;
          display: inline-block;
          margin: 10px 20px;
          &:hover {
            color: #222;
          }
        }
      }
    }
  }

2. 美团footer

3. 美团订单页

4. 美团注册

<template>
  <div class="mt-register">
    <div class="hd"><!-- 为了占满全屏的下边框 -->
      <div class="header"><!-- 版心居中 -->
        <a href="" class="logo">美团网</a>
        <p>
          已有美团账号？
          <a href="/login">
            <el-button type="primary" size="small">登录</el-button>
          </a>
        </p>
      </div>
    </div>

    <div class="bd">
      <el-form :model="ruleForm" :rules="rules" ref="ruleForm" label-width="100px" class="demo-ruleForm">
        <el-form-item label="昵称" prop="username">
          <el-input v-model="ruleForm.name"></el-input>
        </el-form-item>
        <el-form-item label="邮箱" prop="email">
          <el-input v-model="ruleForm.email"></el-input>
          <el-button type="default" size="small" round>发送验证码</el-button>
          <span class="time">验证码已发送送，剩余34秒</span>
        </el-form-item>
        <el-form-item label="验证码" prop="code">
          <el-input v-model="ruleForm.code"></el-input>
        </el-form-item>
        <el-form-item label="密码" prop="pwd">
          <el-input type="password" v-model="ruleForm.pwd" autocomplete="off"></el-input>
        </el-form-item>
        <el-form-item label="确认密码" prop="cpwd">
          <el-input type="password" v-model="ruleForm.cpwd" autocomplete="off"></el-input>
        </el-form-item>
        <el-form-item>
          <el-button type="primary" @click="submitForm('ruleForm')">同意以下协议并注册</el-button>
        </el-form-item>
      </el-form>
      <div class="xieyi">
        <a href="">《美团网用户协议》</a>
      </div>
    </div>
  </div>
</template>

.mt-register {
  .hd {
    border-bottom: 2px solid #2bb8aa;
    .header {
      width: 980px;
      margin: 0 auto;
      padding: 10px 0;
      .logo {
        text-indent: -9999px;
        width: 54px;
        height: 36px;
        display: inline-block;
        background-image: url(//s0.meituan.net/bs/file/?f=fe-sso-fs:build/assets/sp-normal.2ee5c09.png);
        background-position: -669px -748px;
        background-repeat: no-repeat;
      }
      p {
        float: right;
        color: #666;
      }
    }
  }
  .bd {
    margin: 0 auto;
    padding-top: 30px;
    width: 980px;
    padding-right: 550px;
    box-sizing: border-box;
    .xieyi {
      a {
        margin-left: 100px;
        color: #41B883;
      }
    }
    .time {
      margin-left: 20px;
      font-size: 12px;
      color: #e6a23c;
    }
  }
}

5. 美团登录

<template>
  <div class="mt-login">
    <div class="hd">
      <a href="/">美团网</a>
    </div>
    <div class="bd">
      <img src="//s0.meituan.net/bs/file/?f=fe-sso-fs:build/page/static/banner/www.jpg" width="480" height="370" alt="美团网">
      <div class="form">
        <h3 class="tips"><i class="el-icon-warning"></i>请输入账号</h3>
        <h4>账号登录</h4>
        <el-input
          placeholder="请输入账号"
          prefix-icon="el-icon-user"
          v-model="input2">
        </el-input>
        <el-input
          placeholder="请输入密码"
          prefix-icon="el-icon-key"
          v-model="input2">
        </el-input>
        <div class="footer">
          <el-checkbox v-model="checked">7天内自动登录</el-checkbox>
          <span class="forget">忘记密码?</span>
        </div>
        <el-button class="button">登录</el-button>
      </div>
    </div>
  </div>
</template>

.mt-login {
  width: 980px;
  margin: 40px auto 30px;
  .hd {
    margin: 40px auto 30px;
    a {
      display: block;
      background-image: url(//s0.meituan.net/bs/file/?f=fe-sso-fs:build/assets/sp-retina.b95a7dd.png);
      background-repeat: no-repeat;
      width: 82px;
      height: 54px;
      background-size: contain;
      text-indent: -9999px;
    }
  }
  .bd {
    display: flex;
    img {
      margin-right: 115px;
    }
    .form {
      display: flex;
      width: 270px;
      flex-direction: column;
      .tips {
        margin-bottom: 10px;
        border: 1px solid #f5d8a7;
        border-radius: 2px;
        background-color: #fff6db;
        font-size: 12px;
        padding: 10px;
        i {
          font-size: 18px;
          vertical-align: -2px;
          margin-right: 4px;
        }
      }
      .el-input {
        margin-top: 10px;
      }
      .footer {
        margin-top: 10px;
        .forget {
          color: #2e2f30;
          float: right;
          font-weight: 900;
        }
      }
      .button {
        display: block;
        background-color: #2db3a6;
        color: #fff;
        padding: 12px 15px;
        font-size: 12px;
        border-radius: 3px;
        margin-top: 10px;
        cursor: pointer;
        text-align: center;
        border: none;
      }
    }
  }
}

6. 产品列表页

dl {
            display: none;
            position: absolute;
            top: 28px;
            width: 510px;
            cursor: auto;
            font-size: 12px;
            text-align: left;
            background-color: #fff;
            border: 1px solid #e5e5e5;
            border-radius: 4px;
            padding: 19px 15px 9px;
            z-index: 999;
            &:before {
              content: '';
              position: absolute;
              display: block;
              width: 0;
              height: 0;
              border-color: transparent transparent #e5e5e5;
              border-style: solid;
              border-width: 5px;
              top: -11px;
            }
            &:after {
              content: '';
              display: block;
              width: 0;
              height: 0;
              position: absolute;
              top: -8px;
              left: 16px;
              border-color: transparent transparent #fff;
              border-style: solid;
              border-width:4px;
            }
          }

三角样式

.paixu {
        &:before {
          content: '';
          width: 0;
          height: 0;
          position: absolute;
          top: 0;
          right: 8px;
          border: 4px solid transparent;
          border-bottom-color: #ddd;
        }
        &:after {
          content: '';
          width: 0;
          height: 0;
          position: absolute;
          bottom: 10px;
          right: 8px;
          border: 4px solid transparent;
          border-top-color: #ddd;
        }
      }

总结下：小三角有两种写法，但是都是用伪元素的形式
写法（1）

 {
          content: '';
          width: 0;
          height: 0;
          
          position: absolute;
          bottom: 10px;
          right: 8px;
          
          border: 4px solid transparent;
          border-top-color: #ddd; /*方向朝上就给下边框设置颜色*/
   }

写法（2）

 {
          content: '';
          width: 0;
          height: 0;
          
          position: absolute;
          bottom: 10px;
          right: 8px;
          
          border-color: transparent transparent #fff; /*方向朝下就给下边框设置颜色*/
          border-style: solid;
          border-width:4px;
}

7. 美团详情页

8. 美团导航

<template>
  <div class="m-nav">
    <ul>
      <li class="has-children">
        <nuxt-link to="/my">我的美团</nuxt-link>
        <dl class="nav-second nav-second-my">
          <dd><nuxt-link to="/my">我的订单</nuxt-link></dd>
          <dd><nuxt-link to="/my">我的收藏</nuxt-link></dd>
          <dd><nuxt-link to="/my">抵用券</nuxt-link></dd>
          <dd><nuxt-link to="/my">账户设置</nuxt-link></dd>
        </dl>
      </li>
      <li>
        <nuxt-link to="/my">手机APP</nuxt-link>
      </li>
      <li class="has-children">
        <nuxt-link to="/my">商家中心</nuxt-link>
        <dl class="nav-second nav-second-merchant">
          <dd><nuxt-link to="/my">美团餐饮商家中心</nuxt-link></dd>
          <dd><nuxt-link to="/my">登录商家中心</nuxt-link></dd>
          <dd><nuxt-link to="/my">美团智能收银</nuxt-link></dd>
          <dd><nuxt-link to="/my">免费合作美团排队</nuxt-link></dd>
        </dl>
      </li>
      <li class="has-children">
        <nuxt-link to="/my">美团规则</nuxt-link>
        <dl class="nav-second nav-second-my">
          <dd><nuxt-link to="/my">规则中心</nuxt-link></dd>
          <dd><nuxt-link to="/my">规则目录</nuxt-link></dd>
          <dd><nuxt-link to="/my">规则评议院</nuxt-link></dd>
        </dl>
      </li>
      <li class="has-children">
        <nuxt-link to="/my">网站导航</nuxt-link>
        <div class="nav-site nav-second">
          <dl class="nav-third nav-site-hotel">
            <dt>酒店旅游</dt>
            <dd><nuxt-link to="/my">国际机票</nuxt-link></dd>
            <dd><nuxt-link to="/my">火车票</nuxt-link></dd>
            <dd><nuxt-link to="/my">榛果民宿</nuxt-link></dd>
            <dd><nuxt-link to="/my">经济型酒店</nuxt-link></dd>
            <dd><nuxt-link to="/my">主题酒店</nuxt-link></dd>
            <dd><nuxt-link to="/my">商务酒店</nuxt-link></dd>
            <dd><nuxt-link to="/my">公寓</nuxt-link></dd>
          </dl>
          <dl class="nav-third nav-site-food">
            <dt>吃美食</dt>
            <dd><nuxt-link to="/my">烤鱼</nuxt-link></dd>
            <dd><nuxt-link to="/my">特色小吃</nuxt-link></dd>
            <dd><nuxt-link to="/my">烧烤</nuxt-link></dd>
            <dd><nuxt-link to="/my">自助餐</nuxt-link></dd>
          </dl>
          <dl class="nav-third nav-site-movie">
            <dt>看电影</dt>
            <dd><nuxt-link to="/my">热映电影</nuxt-link></dd>
            <dd><nuxt-link to="/my">热门影院</nuxt-link></dd>
            <dd><nuxt-link to="/my">热映电影口碑榜</nuxt-link></dd>
            <dd><nuxt-link to="/my">最受期待电影</nuxt-link></dd>
            <dd><nuxt-link to="/my">国内票房榜</nuxt-link></dd>
          </dl>
          <dl class="nav-third nav-site-app">
            <dt>手机应用</dt>
            <dd>
              <a href="https://i.meituan.com/mobile/down/meituan">
                <img class="appicon" src="//s0.meituan.net/bs/fe-web-meituan/2d53095/img/appicons/meituan.png" alt="美团app" title="美团app">
              </a>
            </dd>
            <dd>
              <a href="https://waimai.meituan.com/mobile/download/default">
                <img class="appicon" src="//s1.meituan.net/bs/fe-web-meituan/404d350/img/appicons/waimai.png" alt="外卖app" title="外卖app">
              </a>
            </dd>
            <dd>
              <a href="https://phoenix.meituan.com/app/">
                <img class="appicon" src="//s0.meituan.net/bs/fe-web-meituan/404d350/img/appicons/zhenguo.png" alt="榛果app" title="榛果app">
              </a>
            </dd>
            <dd>
              <a href="https://www.dianping.com/app/download">
                <img class="appicon" src="//s1.meituan.net/bs/fe-web-meituan/404d350/img/appicons/dianping.png" alt="点评app" title="点评app">
              </a>
            </dd>
            <dd>
              <a href="https://maoyan.com/app">
                <img class="appicon" src="//s1.meituan.net/bs/fe-web-meituan/404d350/img/appicons/maoyan.png" alt="猫眼app" title="猫眼app">
              </a>
            </dd>
          </dl>
        </div>
      </li>
    </ul>
  </div>
</template>

.m-nav {
    a {
      &:hover {
        color: #FE8C00!important;
      }
    }
    float: right;
    color: #999;
    font-size: 12px;
    ul {
      li {
        float: left;
        height: 40px;
        padding: 12px 14px;
        box-sizing: border-box;
        position: relative;
        a {
          color: #999;
          display: block;
        }
        &.has-children {
          position: relative;
          border-right: 1px solid transparent;
          border-left: 1px solid transparent;
          &:hover {
            dl {
              display: block;
            }
            .nav-site {
              display: block
            }
            background-color: #fff;
            border-color: #E5E5E5;
            box-shadow: 0 3px 5px 0 rgba(0, 0, 0, 0.1);
          }
        }
        .nav-second {
          a {
            color: #999;
          }

          background-color: #fff;
          display: none;
          position: absolute;
          box-shadow: 0 3px 5px 0 rgba(0, 0, 0, 0.1);
          border-bottom-left-radius: 4px;
          border-bottom-right-radius: 4px;
          top: 97%;
          right: -1px;
          z-index: 1000;
          border: 1px solid #E5E5E5;
          text-align: center;
          >dd {
            height: 40px;
            line-height: 40px;
          }
          &::after {
            content: '';
            background: #fff;
            width: 76px;
            height: 3px;
            position: absolute;
            top: -2px;
            right: 0;
          }
        }
        .nav-second-my {
          width: 100%;
        }
        .nav-second-merchant {
          width: 140%;
          border-top-left-radius: 4px;
        }
        .nav-site {
          display: none;
          width: 1200px;
          box-sizing: border-box;
          border-top-left-radius: 4px;
          padding: 30px 36px 36px 47px;

          .nav-third {
            float: left;
            margin-right: 47px;
            dt {
              font-style: 14px;
              color: #333;
              font-weight: 500;
              margin-bottom: 26px;
            }
            dd {
              float: left;
              padding: 5px 0;
            }
          }
          .nav-site-hotel {
            width: 234px;
            dd {
              width: 33.3%;
              text-align: center;
            }
          }
          .nav-site-food {
            width: 156px;
            dd {
              width: 50%;
              text-align: center;
            }
          }
          .nav-site-movie {
            width: 90px;
            dd {
              width: 100%;
              text-align: center;
            }
          }
          .nav-site-app {
            float: right;
            dd {
              margin: 0 8px;
            }
            .appicon {
              width: 60px;
              height: 60px;
            }
          }
        }
      }
    }
  }

9. 美图主页-列表

tab栏下面的白色小三角

.page-index .mt-article .hd dd.active:after {
    content: "";
    display: block;
    width: 2px;
    height: 0;
    position: absolute;
    top: 37px;
    left: 0;
    right: 0;
    margin: auto;
    border-right: 5px solid transparent;
    border-left: 5px solid transparent;
    border-bottom: 7px solid #fff;
}

10. 美团侧面菜单

本篇文章长期更新。。。