.banner {
  padding-top: 80px;
  width: 100%;
  height: 500px;
  background: url("../image/about-banner.jpg") no-repeat center bottom;
}

/* === introduction === */
.introduction {
  display: flex;
  justify-content: space-between;
}

.introduction .intro-left {
  width: 49%;
  height: 140px;
  background: url(../image/intro-bg.png) no-repeat left;
  background-size: 50%;
}

.introduction .intro-text p {
  margin: 10px 0;
}

.introduction .intro-right {
  position: relative;
}

.introduction .intro-right::after {
  content: "";
  width: 80px;
  height: 80px;
  background-color: #009ce7;
  position: absolute;
  right: -18px;
  bottom: -18px;
  z-index: -1;
}

.introduction .intro-right img {
  width: 100%;
  height: 100%;
}

/* 五大优势 */
.advantage .banner {
  background: url("../image/advantage-banner.jpg") no-repeat center bottom;
}

.advantage .adv-item {
  display: flex;
  flex-wrap: wrap;
}

.advantage .adv-item li {
  width: 20%;
}

.advantage .adv-item li:nth-child(odd) {
  background-color: #535353;
  color: #fff;
  cursor: pointer;
  box-sizing: border-box;
  padding: 25px;
}

.advantage .adv-item li:nth-child(odd) h1 {
  font-size: 20px;
  margin: 10px 0 25px;
}

.advantage .adv-item li:nth-child(odd) p {
  text-align: justify;
}

.advantage .adv-item li:nth-child(odd):hover {
  background-color: #009ee3;
}

.advantage .adv-item li:nth-child(even) img {
  width: 100%;
  height: 100%;
}