*{
    padding: 0;
    margin: 0;
}


@media (max-width: 675px){
    form{
        width: 100%;
    }
    form fieldset>div{
        width: 100%;
    }
    form .form-btn{
        width: 190px;
        margin: 30px auto;
    }
}

@media (min-width: 676px){
    form{
        width: 100%;
    }
    form fieldset{
        display: flex;
        justify-content: space-between;
    }
    form fieldset>div{
        width: 25%;
    }
    form fieldset:nth-child(3){
        display: block !important;
        width: 100%;
        margin-bottom: 40px;
    }
    form fieldset:nth-child(3)>div{
        width: 100%;
    }
    form .form-btn{
        width: 210px;
        margin: 0 auto !important;
    }
}