button{
    outline: none;
    cursor: pointer;
    display: block;
    position: relative;
    text-align: center;
    border: 2px solid #FFF;
    background-color: transparent;
    color: #FFF;
    padding: 1em 1.75em;
    font-family: sans-serif;
    font-size: 16px;
    font-weight: 400;
    line-height: 1;
    letter-spacing: .3em;
    text-transform: uppercase;
    transition: all .3s ease;           
}

button:focus,
button:hover{
    color: #65d0a3;
}

button:before,
button:after{
    content: "";
    position: absolute;
    z-index: -1;
    width: 100%;
    height: 50%;
    max-height: 0;
    left: 0;
    background-color: #FFF;
    transition: all .3s ease;
}

button:before{
    top: 0;
}

button:after{
    bottom: 0;
}

button:hover:before,
button:focus:before{
    max-height: 50%;
}

button:hover:after,
button:focus:after{
    max-height: 50%;
}