button{
    outline: none;
    cursor: pointer;
    display: block;
    text-align: center;
    padding: 1.25em 3em;
    border: none;
    color: #FFF;
    background: rgba(0,0,0,.4);
    font-family: sans-serif;
    font-size: 18px;
    font-weight: 300;
    text-transform: uppercase;
    letter-spacing: .1em;
    line-height: 1;
    transition: all .2s ease;
}

button:focus,
button:hover{
    padding: 1em 2em;
    background: rgba(0,0,0,.7);
}