style.css

body    {background-color: #282829;
        color: lightgray;
        overflow-x: hidden;}

.center {text-align: center;
        margin-top: 1%;
        width: 100%;}

h1      {font-size: 1.5em;
        margin: 0;}

a       {text-decoration: none;
        font-size: 0.75em;}
a:link  {color: lightblue;}
a:visited       {color: lightblue;}
a:hover {color: lightgray;
        text-decoration: underline;}

input   {text-align: center;
        font-size: 1.5em;
        width: 25%;
        background-color: #F8F8FF;}

input[type="radio"]     {width: 1%;}

input[type="submit"], [type="reset"]    {width: 10%;
                                        margin: 10px;}

table   {text-align: center;
        margin-left: auto;
        margin-right: auto;
        font-size: 1.5em;
        margin-bottom: 2.5%;
        margin-top: 2.5%;
        width: 25%;}

td, th  {border-style: solid;
        border-width: 1px;
        padding: 8px;}

#otherResultsDiv {
        margin-left: auto;
        margin-right: auto;
        width: 25%;
}

#totalInterestId {
        font-size: 2em;
}

@media only screen
and (max-device-width: 1400px) {
        input {
                font-size: 1em;
        }
        input[type="submit"], [type="reset"]    {margin: 10px;}
        table   {font-size: 1em;}
        #totalInterestId {
                font-size: 1.5em;
        }
}

@media only screen
and (max-device-width: 1000px) {
        input {
                width: 35%;
        }
        input[type="submit"], [type="reset"]    {margin: 10px;
                                                width: 20%;}
        table   {width: 35%;}
        #totalInterestId {
                font-size: 1em;
        }
}

@media only screen
and (max-device-width: 700px) {
        input {
                width: 50%;
        }
        input[type="submit"], [type="reset"]    {margin: 10px;}
        table   {width: 50%;}
        #totalInterestId {
                font-size: 0.75em;
        }
}

@media only screen
and (max-device-width: 500px) {
        input {
                width: 75%;
        }
        input[type="submit"], [type="reset"]    {margin: 10px;
                                                width: 40%;}
        table   {width: 75%;}
}