body {
    padding-top: 60px;
    margin: 0;
    font-family: 'Montserrat', sans-serif;
    font-size: 14px;
    line-height: 1.5;

    background-color: #424040;
    color: #fff;
}

*,
*:before,
*:after {
    box-sizing: border-box;
}


h1,
h2,
h3,
h4,
h5,
h6 {
    margin: 0;
}


.container {
    width: 100%;
    max-width: 1160px;
    margin: 0 auto;
}



.header_title {
    font-family: 'Playfair Display', serif;
    font-weight: 800;
    font-size: 3.2em;
    text-align: center;

    text-transform: uppercase;
}



.card {
    padding: 0px 65px 0px 65px;
    margin: 100px auto;
    width: 330px;
    height: 422px;
    background-color: #525252;
    border: 1px solid #525252;
    border-radius: .5em;

    box-shadow: 0px 4px 11px #00000044;
}


.card_title {
    margin-top: 26px;
    text-align: center;
    font-family: 'Montserrat', sans-serif;
    font-size: 26px;
    font-weight: 700;
    color: #A7A7A7;

    text-transform: uppercase;
}

.card_title:after {
    content: "";
    display: block;
    width: 100%;
    height: 2px;
    margin: 29px 0 30px 0;

    background-color: #424040;

}


.sub_text {
    margin-bottom: 31px;
    text-align: center;
    font-family: 'Montserrat', sans-serif;
    font-size: 14px;
    font-weight: 500;
    color: #A7A7A7;
}


.radio_buttons {
    display: flex;
    flex-direction: row;
    justify-content: space-between;
}


.radio_btn {
    display: flex;
    flex-direction: column;
    padding-top: 6px;
    width: 40px;
    height: 50px;
    border: 1px solid #424040;
    border-radius: .3em;
    color: #A7A7A7;
    background-color: #424040;
}

.label_num {
    margin: 0 auto 3px;
}

#two_num {
    margin: 0 auto;
}

#three_num {
    margin: 0 auto;
}

#four_num {
    margin: 0 auto;
}


.start_btn {
    text-align: center;
}

.start_btn:before {
    content: "";
    display: block;
    width: 100%;
    height: 2px;

    margin: 50px 0 50px 0;

    background-color: #424040;
}


#input_btn {
    font-family: 'Roboto', sans-serif;
    font-size: 18px;
    font-weight: 400;
    color: #525252;
    background-color: #A7A7A7;

    border: none;
    border-radius: .350em;
    width: 180px;
    height: 40px;

    cursor: pointer;
    transition: background-color .2s linear;
}

#input_btn:hover {
    background-color: #dbdbdb;
}



/* Media Query */

@media screen and (min-width: 2000px) {
    .header_title {
        font-size: 4em;
    }
    
    .card {
        margin: 20vh auto;
    }
}

@media screen and (min-width: 768px) and (max-width: 811px) {
    .card {
        margin: 90px auto;
    }
}

@media screen and (min-width: 425px) and (max-width: 767px) {
    body {
        padding-top: 35px;
        padding: 15px 15px 5px 15px;

    }
    .header_title {
        font-size: 2.8em;
    }
    .card {
        width: 330px;
        margin: 80px auto;
    }
    .card_title {
        font-size: 26px;
    }    
    #input_btn {
        width: 170px;
    }
    
}

@media screen and (min-width: 375px) and (max-width: 424px) {
    body {
        padding-top: 15px;
        padding: 15px 15px 5px 15px;

    }
    .header_title {
        font-size: 2.5em;
    }
    .card {
        width: 330px;
        margin: 50px auto;
    }
}

@media screen and (min-width: 320px) and (max-width: 374px) {
    body {
        padding-top: 15px;
        padding: 15px 10px 5px 10px;

    }
    .header_title {
        font-size: 2em;
    }
    .card {
        width: 300px;
        margin: 40px auto;
    }
    .card_title {
        font-size: 24px;
    }    
    #input_btn {
        width: 150px;
    }
    
}

@media screen and (max-width: 319px) {
    body {
        padding-top: 15px;
        padding: 15px 10px 5px 10px;

    }
    .header_title {
        font-size: 2em;
    }
    .card {
        width: 300px;
        margin: 50px auto;
    }
    .card_title {
        font-size: 24px;
    }    
    #input_btn {
        width: 150px;
    }
    
}