div.announce_detail {
    border: 0;
    height: 500px;
    overflow: auto;
    margin: 0 20px 10px 20px;
    padding: 10px;
}
div.announce_detail table {
    min-height: 25px;
    line-height: 25px;
    text-align: center;
    border-collapse: collapse;
    
}

div.announce_detail td {
    border:1px solid #000000;
    padding: 5px 10px;
    text-align: left;
    background: #FFFFFF;
}

div.announce_detail th {
    border:1px solid #000000;
    padding: 5px 10px;
    text-align: left;
    background: #B0C4DE;
}