body {
  margin: 0;
  padding: 0;

}
* {
    box-sizing: border-box;
}

.box {
  background-color: #228b22;
  width: calc(413px * 2 + 120px);
  padding: 50px;
  margin: 0 auto;
  margin-top: 100px;
    position: relative;
    overflow: hidden;
}

@media only screen and (max-width: 767px) {
  .box {
    width: 100%;
    margin-top: 0;
      padding: 65px 50px 35px;
  }
    .pc {
        display: none;
    }
}
@media only screen and (min-width: 768px) {
    .sp {
        display: none;
    }
}


#book_turn {
  text-align: center;
  margin: 0 auto;
  height: 613px;
  width: calc(413px * 2 + 20px);
}

@media only screen and (max-width: 375px) {
  #book_turn {
    width: 100%;
    height: 432px;
  }
}

@media only screen and (max-width: 430px)and (min-width: 376px) {
  #book_turn {
    width: 100%;
    height: 513px;
  }
}

@media only screen and (max-width: 500px)and (min-width: 431px) {
  #book_turn {
    width: 100%;
    height: 610px;
  }
}

@media only screen and (max-width: 600px) and (min-width: 501px) {
  #book_turn {
    width: 100%;
    height: 800px;
  }
}

@media only screen and (max-width: 768px)and (min-width: 601px) {
  #book_turn {
    width: 100%;
    height: auto;
    max-height: 613px;
  }
}



#book_turn img {
  height: 613px;
  width: 100%;
}

@media only screen and (max-width: 767px) {
  #book_turn img {
    height: auto;
    max-height: 1000px;
    width: 100%;
    }
}


.container {
	margin: 0 auto;
}

header {
	margin-bottom: 30px;
}

ul {
	text-align: center;
	list-style: none;
	width: 100%;
	margin-bottom: 30px;
}

ul li {
	width: 50%;
	float: left;
}

ul::after {
	content: "";
	display: block;
	clear: both;
}

#prevpage, #nextpage {
	cursor: pointer;
}

.to-top {
    position: absolute;
    left: 10px;
    bottom: 50px;
}
.to-top a {
    color: #fff;
    text-decoration: none;
}
.to-title {
    bottom: 190px;
}
@media only screen and (min-width: 768px) {
    .to-top {
        -ms-writing-mode: tb-rl;
        writing-mode: vertical-rl;
    }
}
@media only screen and (max-width: 767px) {
    .to-top {
        left: 10px;
        right: 10px;
        margin: auto;
        top: 5px;
        bottom: auto;
        text-align: center;
    }
    .to-title {
        top: 34px;
    }
}

.turn-explain {
    color: #fff;
    position: absolute;
    left: 0;
    right: 0;
    bottom: 15px;
    margin: auto;
    text-align: center;
    font-size: 14px;
}
@media only screen and (max-width: 767px) {
    .turn-explain {
        bottom: 25px;
    }
}