#app {
    width: 100%;
    height: 100%;
    position: relative;
    overflow-x: hidden;
    text-align: center;
}

.card {
    width: 300px;
    height: 150px;
    border-radius: 25px;
    background-color: aqua;
    margin: 10px auto;
    line-height: 150px;
    font-size: 3em;
}

.card:nth-child(odd){
    transition: transform 1s ease;
    transform: translateX(-500%);
}
.card:nth-child(even){
    transition: transform 1s ease;
    transform: translateX(500%);
}

.card.show {
    transform: translateX(0);
}