.course{
  padding: 2rem 10%;
}
.course-title{
  font-size: 1rem;
  font-weight: 500;
  color: #000000;
  line-height: calc(56rem /40);
  text-align: center;
}
.course-desc {
  font-size: 0.45rem;
  color: #4D4D4D;
  line-height: 1rem;
  margin-top: 0.5rem;
  text-align: center;
}
.course-wrap{
  position: relative;
  margin-top: 1.2rem;
}
.course-list{
  position: relative;
}
.course-list::after {
  content: '';
  position: absolute;
  z-index: -1;
  left: 50%;
  top: 1rem;
  width: 1px;
  height: calc(100% + 2rem);
  background-color: rgba(153, 153, 153, 0.5);
}
.course-item:not(:first-child) {
  margin-top: 2rem;
}
.course-item:nth-child(even) > .course-item-container > .course-item-pic {
  order: 1;
  border-top-left-radius: 2rem;
  border-top-right-radius: initial;
  overflow: hidden;
}
.course-item > .course-item-container:not(:first-child) {
  margin-top: 2rem;
}

.course-item-container{
  display: flex;
  align-items: stretch;
  justify-content: space-between;
}
.course-item-pic{
  width: 45%;
  border-top-right-radius: 2rem;
  overflow: hidden;
}
.course-item-image{
  width: 100%;
}
.course-item-content{
  width: 45%;
  padding-top: calc(12rem / 40);
}
.course-item-title{
  position: relative;
  font-size: 0.9rem;
  font-weight: 500;
  color: #C0191F;
  line-height: calc(50rem / 40);
  padding-bottom: 1rem;
}
.course-item-title::after {
  content: ' ';
  position: absolute;
  top: calc(6rem / 40);
  left: -10.64%;
  width: calc(56rem / 40);
  height: calc(36rem / 40);
  background-image: url(./../img/course/icon.png);
  background-size: contain;
  background-repeat: no-repeat;
  transform: translateX(-50%);
  z-index: 1;
}
.course-item:nth-child(even) .course-item-title{
  text-align: right;
}
.course-item:nth-child(even) .course-item-title::after {
  right: -10.64%;
  left: initial;
  transform: rotateY(180deg) translateX(-50%);
}
.course-item-year{
  position: relative;
  font-size: calc(48rem / 40);
  font-family: D-DIN-PRO-Medium, D-DIN-PRO;
  font-weight: 500;
  color: #1A1A1A;
  line-height: calc(58rem / 40);
  padding-bottom: 0.5rem;
}
.course-item-year::after{
  position: absolute;
  content: ' ';
  top: 0.5rem;
  left: -11%;
  transform: translateX(-50%);
  width: 0.4rem;
  height: 0.4rem;
  border-radius: 50%;
  background-color: rgba(192, 25, 31, 1);
  z-index: 1;
}
.course-item:nth-child(even) .course-item-year{
  text-align: right;
}
.course-item:nth-child(even) .course-item-year::after {
  right: -11%;
  left: initial;
  transform: translateX(60%);
}
.course-item-desc{
  font-size: 0.45rem;
  color: #1A1A1A;
  line-height: 1rem;
  text-align: justify;
}

.course-nav{
  position: fixed;
  z-index: 10;
  top: 50%;
  transform: translateY(-50%);
  right: 2rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  visibility: hidden;
  opacity: 0;
  transition: 0.3s all;
}
.course-nav.active {
  visibility: visible;
  opacity: 1;
}
.course-nav-item{
  display: block;
  width: calc(12rem / 40);
  height: calc(12rem / 40);
  border: calc(2rem / 40) solid #999999;
  margin-top: 0.7rem;
  border-radius: 50%;
  text-align: center;
  cursor: pointer;
}

.course-nav-item.active, .course-nav-item:last-child {
  width: 2rem;
  height: 0.8rem;
  line-height: 0.8rem;
  border-radius: 0.4rem;
  border: 1px solid #4D4D4D;
}
.course-nav-item-name{
  display: none;
  font-size: 0.5rem;
  font-weight: 600;
  color: #999999;
  font-family: D-DIN-PRO-Medium, D-DIN-PRO;
}
.course-nav-item:last-child > .course-nav-item-name {
  display: inline-block
}
.course-nav-item.active {
  border-color: rgba(192, 25, 31, 1);
}
.course-nav-item.active > .course-nav-item-name{
  display: inline-block;
  color: rgba(192, 25, 31, 1);
}

.description{
  position: relative;
  z-index: 1;
  padding: 2rem;
  background-image: url(./../img/course/footer.png);
  background-repeat: no-repeat;
  background-size: cover;
  background-position: center center;
  margin-top: 2rem;
  border-radius: 1.2rem 0 0 0;
}
.description-title{
  font-size: 0.9rem;
  font-weight: 600;
  color: #C0191F;
  line-height: calc(50rem / 40);
  padding-left: calc(90rem / 40);
  background-image: url(./../img/course/icon.png);
  background-repeat: no-repeat;
  background-size: calc(56rem / 40) calc(36rem / 40);
  background-position: left center;
}
.description-desc{
  font-size: 0.45rem;
  font-weight: 400;
  color: #4D4D4D;
  line-height: 1rem;
  text-align: justify;
  margin-top: 0.7rem;
}

@media screen and (max-width: 1000px) {
  .course-nav-container{
    display: none;
  }
  .course-list::after {
    background-color: initial;
    width: 0;
  }
  .course-item-container{
    flex-direction: column-reverse;
  }
  .course-item:not(:first-child){
    margin-top: 1rem;
  }
  .course-item > .course-item-container:not(:first-child) {
    margin-top: 1rem;
  }
  .course-item-pic{
    width: 100%;
    margin-top: 1rem;
  }
  .course-item-content{
    width: 100%;
  }
  .course-item:nth-child(even) > .course-item-container > .course-item-pic {
    order: initial;
  }
  .course-item:nth-child(even) .course-item-title {
    text-align: initial;
  }
  .course-item:nth-child(even) .course-item-year{
    text-align: initial;
  }
  .course-item-title{
    padding-left: 2rem;
  }
  .course-item-title::after{
    left: 0;
    transform: translateX(0);
  }
  .course-item:nth-child(even) .course-item-title::after {
    left: 0;
    right: initial;
    transform: initial;
  }
  .course-item-year {
    padding-left: 0;
  }
  .course-item-year::after{
    display: none;
    left: calc(34rem / 40);
    right: initial;
    transform: translateX(-50%);
  }
  .course-item:nth-child(even) .course-item-year::after {
    left: calc(34rem / 40);
    right: initial;
    transform: translateX(-50%);
  }

  .description{
    margin-top: 1rem;
    padding: 1rem 5% 1rem 5%;
  }

  .description-desc{
    margin-top: 0.5rem;
  }
  .courseNav{
    display: none;
  }
  .description-title{
    padding-left: 0;
    padding-top: calc(50rem / 40);
    background-position: left top;
  }
}

@media screen and (max-width: 500px) {
  .course{
    padding: 1rem 5%;
  }
}