*{
    margin: 0;
    padding: 0;
}

img{
    width: 600px;
    float: left;
}

#box{
    width: 600px;
    height: 400px;
    margin-top: 30px;
    margin-left: auto;
    margin-right: auto;
    overflow: hidden;
    position: relative;
    box-shadow: 10px 10px 5px #888;
}

#pics{
    width: 5400px;
    height: 400px;
    position: absolute;
    z-index: 1;
}

#dots{
    width: 120px;
    height: 10px;
    position: absolute;
    bottom: 25px;
    left: 40%;
    z-index: 2;
}

#dots span{
    width: 10px;
    height: 10px;
    float: left;
    margin-right: 5px;
    background: #333;
    border: solid 1px #FFF;
    border-radius: 50%;
    cursor: pointer;
}

#dots .on{
    background: orangered;
}
#dots span:hover{background: orangered;}

.turn{
    width: 40px;
    height: 40px;
    color: #fff;
    background: orangered;
    line-height: 39px;
    text-align: center;
    font-size: 36px;
    font-weight: bold;
    opacity: 0.5;
    position: absolute;
    top: 180px;
    display: none;
    z-index: 2;
    cursor: pointer;
}
.turn:hover{opacity: 0.8}
#box:hover .turn{display: block}


#pre{left: 20px;}
#next{right: 20px;}