.wrapper {
    width: 100%;
    /*height: 200px;*/
    position: relative;
    margin: 40px auto 0;
    background: #ccc;
    overflow: hidden;
}
.box {
    position: absolute;
    background: red;
    font-size: 25px;
    /*line-height: 100px;*/
    text-align: center;
}
.box img{
    width: 100%;
    height: 100%;
}
.box:nth-child(odd) {
    background: #f8f8f8;
}
.box:nth-child(even) {
    background: #eee;
}
.boxes {
    position: relative;
    left: -100px;
}