span.abbcode {
    position: relative; 
    display: inline-block;
}

ul.abbcodelist {
    display: none; 
    position: absolute;
    top: 100%; 
    left: 0;   
    margin: 0;
    padding: 0;
    width: 120px; 
    height: auto; 
    max-height: 200px; 
    background-color: #fff;
    border: 1px solid #aaa;
    border-radius: 3px;
    z-index: 1; 
    opacity: 1;
    list-style-type: none;
    box-shadow: 0 4px 8px rgba(0,0,0,0.2);
}

span.abbcode:hover ul.abbcodelist {
    display: block;
}

ul.abbcodelist li {
    padding: 5px 10px;
    cursor: pointer;
    color: #666;
}

ul.abbcodelist li:hover {
    background-color: #ddd;
    color: #000;
}