index.css

body {
    font-family: 'Trebuchet MS', 'Lucida Sans Unicode', 'Lucida Grande', 'Lucida Sans', Arial, sans-serif;
    background-image: url(blackjack.jpg);
    background-size: cover;
    font-weight: bold;
    text-align: center;
    border: 15px solid rgb(218, 165, 32, .54);
    width: 300px;
    margin-left: 500px;
    margin-top: 125px;
}

h1 {
    color: goldenrod;
    font-size: 320%;
}

p {
    color: white;
    font-size: 125%;
}

label {
    color: white;
    font-size: large;
    font-style: oblique;
}

#message-el {
    font-style: oblique;
    color: white;
    font-size: 150%;
}

#start-btn {
    padding: 10px;
    border: none;
    color: #016930;
    font-size: larger;
    font-weight: bold;
    width: 175px;
    background-color: goldenrod;
    border-radius: 4px;
    margin-bottom: 8px;
}
#newcard-btn {
    padding: 10px;
    border: none;
    color: #016930;
    font-size: larger;
    font-weight: bold;
    width: 175px;
    background-color: goldenrod;
    border-radius: 4px;
    margin-bottom: 30px;
}

#input {
    margin-bottom: 8px;
    margin-top: 4px;
}

#username-el{
font-size: large;
}

#submit-btn {
    padding: 10px;
    border: none;
    color: #016930;
    font-size: larger;
    font-weight: bold;
    width: 175px;
    background-color: goldenrod;
    border-radius: 6px;
    margin-bottom: 8px;
}

#reset-btn {
    padding: 10px;
    border: none;
    color: goldenrod;
    font-size: larger;
    font-weight: bold;
    width: 175px;
    background-color: red;
    border-radius: 6px;
    margin-bottom: 8px;

}

#playagain-btn{
    padding: 10px;
    border: none;
    color: #016930;
    font-size: larger;
    font-weight: bold;
    width: 175px;
    background-color: goldenrod;
    border-radius: 6px;
    margin-bottom: 8px;
}