.case-study {
  text-align: center;
  width:100%;
  position: relative;
}

.case-study .bg {
  position: absolute;
  top: 0px;
  left: 0;
  height: 1000px;
  z-index: -10;
  width: 100%;
}

.case-study .title {
  padding-top: 140px;
  font-size: 3.2rem;
  font-weight: bold;
  margin-bottom: 60px;
}

.case-study .youtube-player {
  width: 60%;
  max-width: 700px;
  height: auto;
  margin: 60px auto 100px;
  text-align: center;
  font-size: 1.8rem;
  font-weight: bold;
}

.case-study .youtube-player img {
  margin-bottom: 20px;
}

.case-study .slider {
  width: 700px;
  margin: 0 auto 120px;
}

.case-study .slider .slide-item .flex {
  display: -webkit-box;
  display: -ms-flexbox;
  display: flex;
  justify-content: space-between;
}

.case-study .slider .slide-item .flex .sl-img {
  padding-top: 40px;
  width: 300px;
}

  .case-study .slider .slide-item .flex .textarea {
    line-height: 1.8;
  }

.case-study .slider .slide-item .flex .textarea .topic {
  font-weight: bold;
  font-size: 2.2rem;
  text-align: left;
  margin-bottom: 20px;
  line-height: 150%;
}

.case-study .slider .slide-item .flex .textarea .slide-name {
  font-size: 1.8rem;
  text-align: right;
  font-weight: bold;
  margin-bottom: 30px;
}

.case-study .slider .slide-item .flex .textarea .slide-text {
  font-size: 1.4rem;
  text-align: left;
  border-bottom: 8px solid #f4cd2c;
  line-height: 180%;
  padding-bottom: 20px;
}

.case-study .slide-arrow {
  display: flex;
}

.case-study .slide-prearrow,
.case-study .slide-nextarrow {
  position: absolute;
  top: 200px;
  width: 21px;
  height: 56px;
}

.case-study .slide-prearrow {
  right: -90px;
}

.case-study .slide-nextarrow {
  left: -90px;
}

/* SP */
@media screen and (max-width:600px) {
  .case-study .youtube-player {
    width: 100%;
    height: auto;
    font-size: 1.4rem;
  }

  .case-study .youtube-player img {
    margin-bottom: 10px;
  }

  .case-study .title {
    padding-top: 100px;
    margin-bottom: 50px;
  }

  .case-study .bg {
    height:300px;
  }

  .case-study .youtube-player {
    width: 100%;
  }

  .case-study .slider {
    width: 100%;
    margin: 0;
    padding: 0 30px;
  }

  .case-study .slider .slick-track {
    width: auto !important;
    transform: translate3d(0, 0, 0) !important;
  }

  .case-study .slider .slick-slide:first-child,
  .case-study .slider .slick-slide:nth-child(n+4) {
    display: none !important;
  }

  .case-study .slider .slick-slide:first-child,
  .case-study .slider .slick-slide:nth-child(n+5) {
    display: none !important;
  }

  .case-study .slider .slick-list {
    height: auto !important;
  }

  .case-study .slider .slick-arrow {
    display: none !important;
  }

  .case-study .slider .slide-item .flex {
    flex-direction: column-reverse;
  }

  .case-study .slider .slide-item .flex .sl-img {
    padding: 0;
    width: 100%;
  }

  .case-study .slider .slide-item .flex .sl-img img {
    margin: 0 auto;
  }

  .case-study .slider .slide-item .flex .textarea {
    margin-top: 45px;
    max-width: 600px;
    margin: 30px auto 70px;
  }

  .case-study .slider .slide-item .flex .textarea br {
    display: none;
  }

  .case-study .slider .slide-item .flex .textarea .topic {
    font-size: 2rem;
    margin-bottom: 14px;
  }

  .case-study .slider .slide-item .flex .textarea .slide-name {
    font-size: 1.6rem;
  }

  .case-study .slider .slide-item .flex .textarea .slide-text {
    border: none;
    font-size: 1.4rem;
    padding-bottom: 0;
    text-align: justify;
    line-height: 2.4rem;
  }

  .case-study .slider .slide-item .flex .textarea .slide-text br {
    display: none;
  }
}

@media screen and (min-width:601px) and (max-width:900px) {
  .case-study .bg {
    height:500px;
  }
  .case-study .slider {
    width: 60%;
    margin: 0 auto 120px;
  }
  .case-study .slider .slide-item .flex .sl-img {
    width: 30%;
    padding-top: 182px;
  }
  .case-study .slider .slide-item .flex .textarea {
    width: 65%;
  }
  .case-study .slider .slide-item .flex .textarea .topic {

  }
  .case-study .slider .slide-item .flex .textarea .slide-text br{
    display: none;
  }
  }
}