* {
  margin: 0;
  padding: 0;
}

.flex-center {
  display: flex;
  align-items: center;
  justify-content: center;
}

.flex-column-center {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
}

img {
  width: 100%;
  height: auto;
}

@media screen and (min-width: 751px) {
  body, html, ul, li, p, h3 {
    margin: 0;
    padding: 0;
    color: rgba(255, 255, 255, 1);
  }

  li {
    list-style-type: none;
  }

  a {
    color: rgba(255, 255, 255, 1);
    text-decoration: none;
  }

  nav, section, footer {
    width: 100%;
  }

  .nav, .wawa-index, .about {
    margin: 0 auto;
    width: 80%;
    overflow: hidden
  }

  .nav {
    /*width: 1500px;*/
    display: flex;
    align-items: center;
    justify-content: space-between;
  }

  nav {
    position: fixed;
    top: 0;
    height: 80px;
    background: rgba(36, 35, 96, 1);
    overflow: hidden;
    z-index: 1;
  }

  .wawa__logo {
    height: 50px;
    display: flex;
    align-items: center;
    justify-content: space-around;
  }

  .logo-pic {
    width: 50px;
    height: 50px;
    border-radius: 5px;
  }

  .logo-text{
    font-size: 30px;
    font-weight: bold;
    color: #FFFFFF;
    margin-left: 10px;
  }

  .nav__list {
    height: 100%;
    /*float: right;*/
  }

  .item {
    position: relative;
    display: inline-block;
    margin: 24px 0 24px 60px;
    color: rgba(255, 255, 255, 1);
    font-size: 24px;
  }

  .item-line {
    border-bottom: 3px solid rgba(255, 255, 255, 1);
  }

  .centen-index {
    padding-top: 130px;
    background: rgba(20, 19, 64, 1);
  }

  .centent-about {
    padding-top: 130px;
    background: rgba(20, 19, 64, 1);
  }

  .wawa-index {
    overflow: hidden;
  }

  .wawa-show {
    float: left;
    margin-left: 330px;
    border-radius: 10px;
  }

  .show-pic {
    width: 18vw;
    height: auto;
    border-radius: 10px;
  }

  .wawa-text {
    float: right;
    margin-right: 350px;
    padding-top: 140px;
  }

  .title-pic {
    width: 327px;
    height: auto;
  }

  .download {
    padding-top: 80px;
  }

  .download a {
    display: block;
    margin-bottom: 20px;
    width: 14vw;
    height: auto;
  }

  .download a img {
    width: 100%;
    height: auto;
  }

  .about {
    padding: 0 30px;
    box-sizing: border-box;
  }

  h3 {
    font-size: 36px;
    position: relative;
  }

  h3::after {
    content: "";
    display: block;
    position: absolute;
    top: 50px;
    left: 6px;
    width: 135px;
    height: 4px;
    border-radius: 100px;
    background: #ffffff;
  }

  .about p {
    padding-top: 36px;
    font-size: 24px;
    line-height: 32px;
  }


  footer {
    text-align: center;
    padding: 340px 0 56px;

    background: rgba(20, 19, 64, 1);
    font-size: 24px;
  }
}

@media screen and (max-width: 750px) {
  html, body {
    font-family: PingFangSC-Medium, PingFang SC;
    background: #141340;
  }

  html {
    font-size: calc(100vw / 37.5);
  }

  .mobile-nav {
    width: 37.5rem;
    height: 5rem;
    background: #242360;
    display: flex;
    align-items: center;
    justify-content: space-between;
    position: fixed;
    top: 0;
    left: 0;
  }

  .mobile-logo {
    height: 2.5rem;
    background-size: 100% 100%;
    margin-left: 3rem;
    display: flex;
    align-items: center;
    justify-content: space-around;
  }

  .mobile-logo-img{
    width: 2.5rem;
    height: 2.5rem;
    border-radius: 0.2rem;
  }

  .mobile-logo-text{
    font-size: 1.5rem;
    font-weight: bold;
    color: #FFFFFF;
    margin-left: 5px;
  }

  .mobile-nav-list {
    margin-right: 2rem;
  }

  .mobile-nav-text {
    height: 2.2rem;
    font-size: 1.2rem;
    color: #FFFFFF;
    font-weight: bold;
    line-height: 1.7rem;
    margin: 0 0.5rem;
    box-sizing: border-box;
  }

  .active {
    border-bottom: 0.2rem solid #ffffff;
  }

  .mobile-content {
    margin-top: 5rem;
    height: calc(100vh - 10rem);
  }

  .mobile-home, .mobile-about {
    width: 100%;
    height: 100%;
  }

  .mobile-home-page {
    width: 16.2rem;
    height: 33.1rem;
    background: url("../images/show.png") no-repeat;
    background-size: 100% 100%;
    margin-right: 2rem;
  }


  .mobile-home-info {
    width: 15.9rem;
    height: 9.7rem;
    background: url("../images/title.png") no-repeat;
    background-size: 100% 100%;
  }


  .download-img {
    width: 10.5rem;
    height: 3.2rem;
    margin-top: 2rem;
  }


  .about-text {
    width: 33rem;
    font-size: 1.6rem;
    color: #ffffff;
    margin: 3rem 0 0;
  }

  .mobile-footer {
    width: 30rem;
    height: 5rem;
    margin: 0 auto;
  }

  .mobile-footer-text {
    font-size: 1.4rem;
    color: #ffffff;
    text-align: center;
  }


}