.middle-box {
  /*border-radius: 5px;*/
  /*background: rgba(215, 229, 241, 0.2);*/
  padding: 20px;
}

.middle-box:hover {
  /*background: rgba(215, 229, 241, 0.25);*/
}

.logo {
  margin: 0 auto;
  width: 100%;
  height: 100%;
  background-color: #000;
  position: fixed;
}

.logo canvas {
  width: 100%;
  height: 100%; /*默认全屏显示 可自己设置高度640px*/
  display: inline-block;
  vertical-align: baseline;
  position: fixed;
  z-index: -10;
}

.logo .canvaszz {
  /*用来解决视频右键菜单，用于视频上面的遮罩层*/
  width: 100%;
  background: url(../img/loginbg3.jpg) no-repeat fixed;
  background-size: cover;
  background-position: bottom right;
  height: 100%;
  position: absolute;
  z-index: -20;
  /*filter: alpha(opacity=90);*/
  /*-moz-opacity: 0.9;*/
  /*-khtml-opacity: 0.9;*/
  /*opacity: 0.9;*/
}

.logo .content {
  position: absolute;
  width: 320px;
  /*height: 424px;*/
  padding: 10px;
  top: 50%;
  margin-top: -226px;
  left: 50%;
  margin-left: -160px;
  border: 1px solid #fff;
  border-radius: 10px;
  z-index: 30;
}

.logo .topcn {
  margin-top: 10px;
}

.logo .nav .gv {
  background: linear-gradient(to right, #55bafe, #3072ff);
  width: 220px;
  height: 40px;
  border-radius: 20px;
  margin: 10px 0;
  border: none;
  text-align: center; /*水平居中*/
  cursor: pointer;
  font-size: 16px;
  /*color: #066197;*/
}
.logo .nav .gv:focus {
  outline: none;
}

/*.logo .nav .gv:hover {*/
/*background: url(../img/nav_gv.png) no-repeat 0 -43px;*/
/*-webkit-box-shadow: 0 0 6px #1d7eb8;*/
/*transition-duration: 0.5s;*/
/*}*/