.poster-main {
    position: relative;
    width: 900px;
    height: 465px
}

.poster-main a,
.poster-main img {
    display: block;
}

.poster-main .poster-list {
    width: 1200px;
    height: 465px;
}

.poster-main .poster-list .poster-item {
    position: absolute;
    left: 0px;
    top: 0px;
 
}

.poster-main .poster-btn {
    position: absolute;
    height: 100%;
    width: 100px;
    top: 0;
    z-index: 10;
    opacity: 0.5;
}
.poster-main .poster-btn i{
    font-size: 50px;
    color: #999;
    position: relative;
    top: 50%;
    cursor: pointer;
    margin-top: -25px;
    display: inline-block;
}
.poster-main .poster-prev-btn {
    left: -100px;
    
}
.poster-main .poster-next-btn {
    right: -100px;
    text-align: right;
}