*{
    margin: 0;
    padding: 0;
}
#box{
    width: 606px;
    height: 606px;
    margin: 60px auto;
}
.div{
    float : left;
    border: 1px solid #ccc;
}

.div-dash {
    position: absolute;
    border: 1px solid #ddd;
    opacity: 0.7;
}

.dash {
    float : left;
    width: 200px;
    height: 200px;
    border: 1px dashed #f00;
}
.shuzi{
    width: 200px;
    height: 200px;
    display: inline-block;
    text-align: center;
    line-height: 200px;
    font-size: 30px;
    font-weight: bold;
}
.shu1{
    background: #598bff;
}
.shu2{
    background: #ff708d;
}
.shu3{
    background: #ffc94d;
}
.shu4{
    background: #2ce69b;
}
.shu5{
    background: bisque;
}
.shu6{
    background: thistle;
}
.shu7{
    background: khaki;
}
.shu8{
    background: orangered;
}
.shu9{
    background: cadetblue;
}