/* ------------------------------------------
 * IT书包
 * 网址：www.itshubao.com
 * 整理：yinq<3331653644@qq.com> 
 -------------------------------------------- */
html, body {
  width: 100%;
  height: 100%;
  margin: 0;
  font-family: 'Microsoft YaHei', cursive;
  background: #7474BF;
  background: -webkit-linear-gradient(right, #7474BF, #348AC7);
  background: linear-gradient(to left, #7474BF, #348AC7);
}

.container {
  display: -webkit-box;
  display: -ms-flexbox;
  display: flex;
  -webkit-box-orient: vertical;
  -webkit-box-direction: normal;
      -ms-flex-direction: column;
          flex-direction: column;
  -webkit-box-pack: center;
      -ms-flex-pack: center;
          justify-content: center;
  -webkit-box-align: center;
      -ms-flex-align: center;
          align-items: center;
}

h1 {
  margin: 0;
  text-transform: uppercase;
  color: #fff;
}

div[class*=box] {
  width: 600px;
  height: 400px;
  overflow: hidden;
  position: relative;
  margin-bottom: 60px;
  box-shadow: 6px 5px 30px -4px rgba(0, 0, 0, 0.55);
}

.btn {
  width: 50px;
  height: 50px;
  text-align: center;
  padding-top: 8px;
  box-sizing: border-box;
}
.btn.facebook {
  background-color: #3b5998;
}
.btn.twitter {
  background-color: #55acee;
}
.btn.google {
  background-color: #dd4b39;
}
.btn .fa {
  font-size: 35px;
  color: #fff;
}

/*
=========================
        BOX ONE
=========================
*/
.box-1 {
  background-color: #67AAF9;
  margin-top: 60px;
  display: -webkit-box;
  display: -ms-flexbox;
  display: flex;
  -webkit-box-pack: center;
      -ms-flex-pack: center;
          justify-content: center;
  -webkit-box-align: center;
      -ms-flex-align: center;
          align-items: center;
}
.box-1 .share-buttons {
  display: -webkit-box;
  display: -ms-flexbox;
  display: flex;
  -ms-flex-pack: distribute;
      justify-content: space-around;
  -webkit-box-align: center;
      -ms-flex-align: center;
          align-items: center;
  position: absolute;
  top: 50%;
  left: 50%;
  border: 1px solid transparent;
  width: 0;
  height: 0;
  z-index: 10;
  -webkit-transition: all 0.4s 0s,  border 0.4s 0.6s,  height 0.4s 0.4s,  margin 0.4s 0.4s;
  transition: all 0.4s 0s,  border 0.4s 0.6s,  height 0.4s 0.4s,  margin 0.4s 0.4s;
}
.box-1:hover .share-buttons {
  height: 200px;
  width: 400px;
  margin-top: -100px;
  border-color: #dbdbdb;
  background-color: #c4e0f9;
  -webkit-transform: translateX(-200px);
          transform: translateX(-200px);
}
.box-1 .btn {
  opacity: 0;
}
.box-1:hover .btn {
  opacity: 1;
  -webkit-transition: 0.4s;
  transition: 0.4s;
  -webkit-transition-delay: 0.7s;
          transition-delay: 0.7s;
}

/*
=========================
        BOX TWO
=========================
*/
.box-2 {
  background: #C4E0F9;
}
.box-2 .layer {
  position: absolute;
  top: 0;
  left: 0;
  height: 300px;
  -webkit-transition: 0.4s 0.8s;
  transition: 0.4s 0.8s;
}
.box-2:hover .layer {
  -webkit-transition: 0.4s 0s;
  transition: 0.4s 0s;
  -webkit-transform: translateY(250px);
          transform: translateY(250px);
}
.box-2 .layer .inner {
  background-color: #B95F89;
  width: 600px;
  height: 400px;
  position: relative;
  z-index: 5;
  display: -webkit-box;
  display: -ms-flexbox;
  display: flex;
  -webkit-box-pack: center;
      -ms-flex-pack: center;
          justify-content: center;
  -webkit-box-align: center;
      -ms-flex-align: center;
          align-items: center;
}
.box-2 .btn {
  position: absolute;
  top: 10px;
  opacity: 0;
  z-index: 2;
}
.box-2:hover .btn {
  opacity: 1;
  -webkit-transform: translateY(-150px);
          transform: translateY(-150px);
}
.box-2 .facebook {
  left: 20%;
  -webkit-transition: 0.4s 0.6s;
  transition: 0.4s 0.6s;
}
.box-2 .twitter {
  left: 45%;
  -webkit-transition: 0.4s 0.4s;
  transition: 0.4s 0.4s;
}
.box-2 .google {
  left: 70%;
  -webkit-transition: 0.4s 0.2s;
  transition: 0.4s 0.2s;
}

/*
=========================
       BOX THREE
=========================
*/
.box-3 {
  background-color: #2EC0F9;
  -webkit-transition: 1s;
  transition: 1s;
  display: -webkit-box;
  display: -ms-flexbox;
  display: flex;
  -webkit-box-pack: center;
      -ms-flex-pack: center;
          justify-content: center;
  -webkit-box-align: center;
      -ms-flex-align: center;
          align-items: center;
}
.box-3:hover .share-buttons {
  opacity: 1;
  padding: 0 18%;
}
.box-3 .share-buttons {
  position: absolute;
  top: 0;
  left: 0;
  background-color: rgba(0, 0, 0, 0.4);
  width: 100%;
  height: 100%;
  opacity: 0;
  -webkit-transition: 0.4s;
  transition: 0.4s;
  z-index: 10;
}
.box-3 .btn {
  display: inline-block;
  margin: 175px 40px;
}