.class_info {
    margin: 10px 0;
    padding: 10px 5px;
    font-size: 16px;
    text-align: center;
    background-color: rgb(240, 240, 240);
    border: 1px solid silver;
}
.class_info a {
    color: black;
}
.class_error {
    margin: 10px 0;
    padding: 10px 5px;
    font-size: 16px;
    text-align: center;
    background-color: rgba(139, 0, 0, 0.2);
    border: 1px solid rgba(139, 0, 0, 0.4);
    color: darkred;    
}
.class_error a {
    color: darkred;    
}