@charset "utf-8";

.course-box {
  background-image: url('../images/develop/bg.jpg');
  background-size: cover;
  background-position: center;
  background-repeat: no-repeat;
  padding-top: 49px;
}

.course-title h2 {
  font-family: SourceHanSansSC-Bold, SourceHanSansSC-Bold;
  font-weight: normal;
  font-size: 52px;
  color: #FFFFFF;
  line-height: 61px;
}

.course-title span {
  font-family: SourceHanSansSC-Medium, SourceHanSansSC-Medium;
  font-weight: normal;
  font-size: 31px;
  color: #FFFFFF;
  line-height: 36px;
}

.course {
  font-family: Microsoft YaHei-Bold, Microsoft YaHei;
  padding-top: 91px;
  padding-bottom: 91px;
  padding-left: 136px;
  padding-right: 136px;
  overflow: hidden;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.course img {
  max-width: 100%;
}

.timeline {
  position: relative;
  padding: 0;
}

.timeline-line {
  position: absolute;
  left: 50%;
  top: 37px;
  bottom: 28px;
  width: 2px;
  background: #fff;
  transform: translateX(-50%);
}

.timeline-item {
  position: relative;
  margin-bottom: 36px;
}

.timeline-item:last-child {
  margin-bottom: 0;
}

.timeline-item.left-item {
  padding-right: calc(50% + 60px);
}

.timeline-item.right-item {
  padding-left: calc(50% + 60px);
}

.timeline-content {
  color: #FFFFFF;
}

.left-item .timeline-content {
  text-align: right;
}

.right-item .timeline-content {
  text-align: left;
}

.timeline-year {
  font-size: 48px;

  color: #F7F7F7;
}

.timeline-subtitle {
  font-size: 50px;
  color: #F7F7F7;
  margin-bottom: 16px;

}

.timeline-desc {
  font-size: 24px;
  line-height: 35px;
  color: #F7F7F7;
  text-align: justify;
}

.timeline-dot {
  position: absolute;
  top: 28px;
  width: 42px;
  height: 42px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.timeline-dot img {
  width: 100%;
  height: 100%;
}

.left-item .timeline-dot {
  right: calc(50% - 21px);
}

.right-item .timeline-dot {
  left: calc(50% - 21px);
}

.course .about-pc {
  width: 1374px;
  display: block;
}

.course .about-phone {
  display: none;
}



@media screen and (max-width: 767px) {
  .course-box {
    padding-top: 0;
  }

  .course {
    padding: 1rem 0.3rem;
    padding-bottom: 1rem;
  }

  .course .about-pc {
    display: none;
  }

  .course .about-phone {
    display: block;
  }

  .timeline-phone {
    position: relative;
    padding-left: 0.3rem;
  }

  .timeline-line-phone {
    position: absolute;
    left: 0.16rem;
    top: 0;
    bottom: 0;
    width: 2px;
    background: rgba(255, 255, 255, 0.3);
  }

  .timeline-item-phone {
    position: relative;
    margin-bottom: 0.6rem;
  }

  .timeline-item-phone:last-child {
    margin-bottom: 0;
  }

  .timeline-dot-phone {
    position: absolute;
    left: -0.33rem;
    top: 0;
    width: 0.42rem;
    height: 0.42rem;

  }

  .timeline-dot-phone img {
    width: 100%;
    height: 100%;
  }

  .timeline-content-phone {
    color: #FFFFFF;
    padding-left: 0.6rem;
  }

  .timeline-year-phone {
    font-size: 0.47rem;
   
  }

  .timeline-subtitle-phone {
    font-size: 0.5rem;
    margin-bottom: 0.28rem;
  }

  .timeline-desc-phone {
    font-size: 0.3rem;
    color: #F7F7F7;
    line-height: 0.5rem;
  }
}