body {
    margin: 0px;
    font-family: sans-serif;
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    background: linear-gradient(blueviolet, rgb(79, 21, 134));
}

#insert {
    background-color: white;
    padding: 50px;
}

.key {
    display: inline-flex;
    align-items: center;
    flex-direction: column;
    border: none;
    background-color: rgba(137, 43, 226, 0.767);
    color: white;
    padding: 20px;
    font-size: 20px;
    font-weight: bold;
    margin: 10px 10px 15px 10px;
    min-width: 150px;
    position: relative;
}

.key small {
    text-align: center;
    width: 100%;
    position: absolute;
    font-size: 14px;
    color: #555;
    top: -24px;
    left: 0px;
}