* {
    margin: 0;
    padding: 0;
  }
  body,
  h1,
  h2,
  h3,
  h4,
  p,
  a,
  input,
  img,
  ul,
  li,
  ol,
  dl,
  dt,
  dd {
    padding: 0;
    margin: 0;
  }
  ul,
  ol {
    list-style: none;
  }
  img {
    display: block;
    border: 0;
  }
  input {
    outline: none;
  }
  header,
  footer,
  section,
  main,
  nav {
    display: block;
  }
  body {
    font-family: "微软雅黑";
    color: #3e3e3e;
    font-size: 0.34rem;
  }
  a {
    text-decoration: none;
    color: #333;
  }
  i {
    font-style: normal;
  }
  * {
    box-sizing: border-box;
    outline: none;
    -webkit-tap-highlight-color: rgba(0, 0, 0, 0);
  }
  *:hover,
  *:visited,
  *:link,
  *:active,
  *:focus {
    -webkit-tap-highlight-color: rgba(0, 0, 0, 0);
  }
  html,
  body {
    width: 100%;
    height: 100%;
    /* max-width: 720px; */
    margin: 0 auto;
  }

  .flex {
    overflow: hidden;
    display: flex;
  }
  .flex-vertical {
    /* 上线布局 */
    height: 100%;
    flex-direction: column;
  }
  .flex-item {
    flex: 1;
    overflow-y: auto;
    -webkit-overflow-scrolling: touch;
    position: relative;
  }
  .flex-align-top {
    align-items: flex-start;
  }
  .flex-align-middle {
    align-items: center;
  }
  .flex-align-bottom {
    align-items: flex-end;
  }
  .flex-justify-start {
    justify-content: flex-start;
  }
  .flex-justify-end {
    justify-content: flex-end;
  }
  .flex-justify-center {
    justify-content: center;
  }
  .flex-justify-between {
    justify-content: space-between;
  }
  .flex-justify-around {
    justify-content: space-around;
  }