@media only screen and (max-width: 476px){
    .card_box{
        width: 300px;
    }

    .background{
        width: 290px;
    }

    .timer_display {
        font-size: 26px;
    }

    #pause_timer, #reset_timer,#start_timer {
        padding: 12px 19px;
        font-size: 10px;
    }

    
}