w

ul{
    list-style-type: none;
}

.li{
    width: 180px;
    height: 50px;
    font-weight: bold;
    font-family: 'Courier New', Courier, monospace;
    margin:50px auto;
    display: inline-block;
    text-align: center;
    color: white;
    cursor: pointer;
    background-color: black;
}

ul > li > a {
    width: 180px;
    height: 50px;
    display: block;
    color: white;
    text-align: center;
}
ul > li:hover{
    
    background-color: silver;
}
html {
    background-color: black;
}

ul > li > ol{
    padding: 0;
    list-style-type: none;
    display: none;
    position: absolute;
}
ul > li:hover ol {
    display: block;
}

ul > li > ol > li {
    background-color: black;
    text-align: center;
    cursor: pointer;
    display: block;
    width: 9vw;
}
ul > li > ol > li > a {
    color: white;
}