.countdown_container {
    color: #333;
    margin: 0 auto;
    text-align: center;
}

.countdown_h1 {
    font-weight: normal;
    letter-spacing: .125rem;
    text-transform: uppercase;
}

.countdown_li {
    display: inline-block;
    font-size: 1.2em;
    list-style-type: none;
    padding: 1em; 
    text-transform: uppercase;
}

    .countdown_li span {
        display: block;
        font-size: 2.2rem;
    }