* {
  padding: 0px;
  margin: 0px;
  font-size: 16px;
  color: #333;
  font-family: "Microsoft YaHei";}
a,
a:link,
a:visited,
a:hover,
a:active {
  text-decoration: none;}
::-moz-selection {
  background: #338fff;
  color: #fff;}
::-webkit-selection {
  background: #338fff;
  color: #fff;}
::selection {
  background: #338fff;
  color: #fff;}
.clear::after {
  content: "";
  display: block;
  height: 0px;
  clear: both;
  visibility: hidden;}
.response-img {
  display: block;
  max-width: 100%;}
.text-overflow {
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;}
body {
  width: 100%;
  max-width: 1920px;
  padding-bottom: 0;}
#knowledge {
  width: 100%;
  position: relative;
  padding: 80px 0 80px;}
.bookBox {
  width: 1100px;
  height: 697px;
  position: relative;
  margin: 30px auto;
  -webkit-perspective-origin: 50% 60%;
  perspective-origin: 50% 60%;
  -webkit-perspective: 1500px;
  perspective: 1500px;
  background: url(../images/bookbg2.png) no-repeat 0 0;
  background-size: 100% 100%;}
.bookBox:hover .lastBtn {
  display: block;}
.bookBox:hover .nextBtn {
  display: block;}
.bookPage {
  position: absolute;
  width: 550px;
  height: 697px;
  top: 0;
  -webkit-transform-style: preserve-3d;
  -moz-transform-style: preserve-3d;
  -ms-transform-style: preserve-3d;
  -o-transform-style: preserve-3d;
  transform-style: preserve-3d;
  -webkit-transition: all linear 2s;
  -moz-transition: all linear 2s;
  -ms-transition: all linear 2s;
  -o-transition: all linear 2s;
  transition: all linear 2s;
/*   background: url(../img/bookleft.png) no-repeat; */
  background-size: 479.26px 483.33px;
  background-position: 20.74px 8.3px;}
.bookPage > img {
  position: absolute;
  top: 10px;
  left: 24px;
  display: inline-block;
  width: 484px;}
.reversal {
  transform: rotateY(180deg);
  -webkit-transform: rotateY(180deg); /* safari and chrome */
  -moz-transform: rotateY(180deg);}
.bookWord {
  position: absolute;
  top: 10px;
  left: 25px;
  display: inline-block;
  width: 480px;
  height: 640px;
  font-size: 20px;
  line-height: 27px;
  backface-visibility: visible;
  background-color: #f0f0f0;
  word-break: break-all;
  -webkit-column-count: 2;
  -webkit-column-gap: 40px;
  -moz-column-count: 2;
  -moz-column-gap: 40px;
  -ms-column-count: 2;
  -ms-column-gap: 40px;
  column-count: 2;
  column-gap: 40px;}
.bookWord  img {
  width: 480px;
  height: 640px;
  display: block;}
.bookWord span {
  font-size: 30px;
  line-height: 40px;
  line-height: 40px;
  color: #7e7e7e;}
.frist {
  left: 0;
  z-index: 1;}
.frist img {
  z-index: 1;}
.last {
  right: 0;
  z-index: 1;}
.last p {
  z-index: 1;}
.runPage {
  right: 0;
  -webkit-transform-origin: 0 0;
  -moz-transform-origin: 0 0;
  -ms-transform-origin: 0 0;
  -o-transform-origin: 0 0;
  transform-origin: 0 0;}
.runPage,
.bookPage:last-child {
/*   background: url(../img/bookright.png) no-repeat; */
  background-size: 479.26px 483.33px;
  background-position: 0 8.3px;}
.runClass {
  -webkit-transform: rotateY(-180deg);
  -moz-transform: rotateY(-180deg);
  -ms-transform: rotateY(-180deg);
  -o-transform: rotateY(-180deg);
  transform: rotateY(-180deg);}
.lastBtn,
.nextBtn {
  display: none;
  position: absolute;
  top: 300px;
  cursor: pointer;
  z-index: 999;
  font-size: 50px;
  line-height: 100px;
  color: #fff;
  text-decoration: none;
  background-color: rgba(0, 0, 0, 0.5);}
.lastBtn {
  left: 0;}
.nextBtn {
  right: 0;}
.canvasBox {
  display: block;
  width: 158px;
  height: 158px;}
.pageNumber {
  position: absolute;
  bottom: -40px;
  right: 0;
  font-size: 20px !important;
  line-height: 30px;}