CSS不起作用,该怎么解决

if($auth==true)
{
    echo "";
    echo "You have\$$credit";
    echo "Start Order";
    echo "View Order";
    echo "Edit Profile";
    echo "Change Password";
    echo "Recharge My Account";
    echo "Logout";
    echo "";
}

.block_link a
{
    width:120px;
    height:50px;
    display: block;

    background-color:#f1f1f1;
    text-align:center;
    font-size:10.5pt;
    text_decoration:none; //去链接下划线不起作用
    padding-top:30px;
}

.block_link a:link, block_link a:visited  //这里的a:visited 也不起作用
{
    background-color: #f1f1f1;
    text_decoration:none; //去链接下划线不起作用
    color:#009EDD;
}

.block_link a:hover
{
    background-color: #009EDD;
    text_decoration:none; //去链接下划线不起作用
    color:#ffffff;
}

#block_link
{
    background-color:#d34836;
    color:#ffffff;
    width:120px;
}