.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/loginbg2.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;*/
/*}*/