#container {
    text-align: center;
    padding: 20px
}

h1 {
    color: #333;
}

button, select {
    margin: 10px 0;
    padding: 10px;
    font-size: 16px;
    border-radius: 10px;
    border: 1px solid;
    border-color: black;
}

button:hover {
    background-color: darkgrey;
}

button:active {
    background-color: gray;
}

#result {
    margin: 10px;
}