.box_donghua {
    top: 0;
    right: 0;
    bottom: 0;
    left: 0;
    position: fixed;
    /* background: url(../images/bg.jpg) center no-repeat; */
    z-index: 100000000;
    width: 100%;
    height: 100%;
}

.load2bg1,
.load2bg2 {
    transition: 0.9s ease;
    height: 100%;
    opacity: 1;
}

.load2bg1 {
    background: url(./images/bg01.jpg) right center no-repeat;
    left: 0;
    right: auto;
}

.load2bg2 {
    background: url(./images/bg02.jpg) left center no-repeat;
}

.load2bg1,
.load2bg2 {
    position: fixed;
    right: 0;
    width: 50%;
    z-index: 990;
    top: 0;
    bottom: 0;
    transition: all 1s cubic-bezier(0.215, 0.61, 0.355, 1) 0s;
}

.load2bg1.on {
    width: 0;
    opacity: 0;
}

.load2bg2.on {
    width: 0;
    opacity: 0;
}


/* --------------- */

.box_donghua .index-cont {
    position: fixed;
    top: 0;
    right: 0;
    bottom: 0;
    left: 0;
    z-index: 10000000;
    transition: 0.6s;
}

.box_donghua .index-cont.on {
    opacity: 0;
}

.box_donghua .index-cont .logo {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    opacity: 0;
    transition: all 2.5s;
}

.box_donghua .index-cont .logo.on {
    opacity: 1;
}

.box_donghua .index-cont .lines {
    width: 300px;
    height: 300px;
    position: absolute;
    left: 50%;
    margin-left: -150px;
    top: 50%;
    margin-top: -150px;
    z-index: 998;
    overflow: hidden;
}

.box_donghua .index-cont .lines .top {
    position: absolute;
    top: 0;
    left: -300px;
    transition: all 0.6s linear;
    -webkit-transition: all 0.6s linear;
    height: 1px;
    width: 300px;
    background: rgba(255, 255, 255, 0.5);
}

.box_donghua .index-cont .lines .top.on {
    left: 0;
}

.box_donghua .index-cont .lines .right {
    position: absolute;
    right: 0;
    top: -300px;
    transition: all 0.6s linear;
    -webkit-transition: all 0.6s linear;
    width: 1px;
    height: 300px;
    background: rgba(255, 255, 255, 0.5);
}

.box_donghua .index-cont .lines .right.on {
    top: 0;
}

.box_donghua .index-cont .lines .bottom {
    position: absolute;
    bottom: 0;
    right: -300px;
    transition: all 0.6s linear;
    -webkit-transition: all 0.6s linear;
    height: 1px;
    width: 300px;
    background: rgba(255, 255, 255, 0.5);
}

.box_donghua .index-cont .lines .bottom.on {
    right: 0;
}

.box_donghua .index-cont .lines .left {
    position: absolute;
    left: 0;
    bottom: -300px;
    transition: all 0.6s linear;
    -webkit-transition: all 0.6s linear;
    width: 1px;
    height: 300px;
    background: rgba(255, 255, 255, 0.5);
}

.box_donghua .index-cont .lines .left.on {
    bottom: 0;
}