.project_background_pic_project {
    width: 100%;
    height: 420px;
    background: url("../images/project/banner_project.png") no-repeat center center;
    background-size:cover;
}
.middle {
    padding: 72px 0;
}
.middle .main .shadow {
    opacity: 0;
}
.trade {
    border-radius: 4px;
    width:100%;
    height:100%;
    position: absolute;
    top:0;
    left:0;
    z-index: 5;
    /*background:rgba(0,0,0,0);*/
}

.photo_item_one,.photo_item_two,.photo_item_three,.photo_item_four {
width: 100%;
}
.small_width {
    width: 17.625em;
}
.middle_width {
    width: 22.875em;
}
.big_width {
    width:37.5em;
}
.small_height {
    height:282px;
}
.middle_height {
    height:366px;
}
.big_height {
    height:600px;
}
.photo_item_one_left,.photo_item_one_right,
.photo_item_one_right>div,
.photo_item_two>div,
.photo_item_three_left,.photo_item_three_right,
.photo_item_three_left>div,
.photo_item_four>div
{
    border-radius: 4px;
    position: relative;
    overflow: hidden;
}
.desc {
    position: absolute;
    width: 100%;
    top: 50%;
    left: 50%;
    transform: translateX(-50%) translateY(-24px);
    z-index: 9999;
}
.desc_title {
    width: 10.25em;
    height: 48px;
    font-size: 1.25em;
    text-align: center;
    line-height: 48px;
    color: #fff;
    border: 2px solid #fff;
    margin-bottom: 24px;
    position: relative;
    left: 50%;
    z-index: 6;
    transform: translateX(-50%);
}
.desc_content {
    width: 100%;
    font-size: 12px;
    color: #fff;
    text-align: center;
    display: none;
}
.desc_content.show {
    display: block;
}
.desc_content p {
    line-height: 1;
    margin: 7px 0;
}
.photo_item_one_left,.photo_item_one_right {
    float: left;
}
.big_width img{
    width: 100%;
    height: 100%;
}
.photo_item_one_left {
    margin-right: 36px;
}
.photo_item_one_right>div:first-child {
    margin-bottom: 36px;
}
.photo_item_two{
    margin: 36px 0;
}
.photo_item_two>div,.photo_item_four>div {
    float: left;
}
.photo_item_two>div:nth-child(-n+2),.photo_item_four>div:nth-child(-n+2) {
    margin-bottom: 36px;
}
.photo_item_two>div:nth-child(2n),.photo_item_four>div:nth-child(2n) {
    margin-left: 36px;
}
.photo_item_three_left,.photo_item_three_right {
    float: left;
}
.photo_item_three_left {
    margin-right: 36px;
}
.photo_item_three_left>div {
    float: left;
}
.photo_item_three_left>div:first-child {
    margin-bottom: 36px;
}
.photo_item_three_left>div:nth-child(2) {
    margin: 0 36px 0 0;
}
.photo_item_four {
    margin-top: 36px;
}