body {
    margin: 0px;
    padding: 0px;
}

/* the whole container */
#alphabet {
    display: flex;
    flex-flow: column nowrap;
    height: 100vh;
    box-sizing: border-box;
    border: solid black 1px;
}

/* a single row */
#alphabet div {
    display: flex;
    flex-grow: 1;
    flex-flow: row nowrap;
    width: 100%;
    background: gray;
    margin: 0px;
}

/* individual entry */
#alphabet div button {
    flex-grow: 1;
    flex-basis: 2em;
    border: none;
    background: #D32F2F;
    color: #fff;
    font-size: 5vh;
    height: 100%;
}

#alphabet div button:hover {
    background: #F44336;
}