styles.css

body {
    margin: 30px auto;
    text-align: center;
    background: #fcfcfc;
}

h1 {
    font-family: Monoton;
    font-size: 70px;
    margin: 0.2em;
}

section {
    box-shadow: 0 10px 50px 0 rgba(0,0,0,.1);
    background: #fff;
    border-radius: 15px;
    width: 350px;
    margin: 40px auto;
    padding: 40px 0;
}

h2 {
    margin: 1em 0 0.25em;
}

h2:first-of-type {
    margin-top: 0.5em;
}

input[type='number'] {
    width: 100px;
    margin: 10px 15px 0;
    border-radius: 2px;
    border: 1px solid #CCC;
    padding: 10px;
    color: #333;
    font-size: 14px;
}

input[type='submit'] {
    display: block;
    padding: 10px 25px;
    width: 110px;
    margin: 30px auto;
    font-size: 14px;
    text-transform: uppercase;
    letter-spacing: 1px;
    cursor: pointer;
    transition: all .3s ease;
    color: #fff;
    background-color: #02b3e4;
    border: .125rem solid transparent;
    box-shadow: 8px 10px 20px 0 rgba(46,61,73,.15);
    border-radius: .25rem;
}

input[type='submit']:hover {
    box-shadow: 2px 4px 8px 0 rgba(46,61,73,.2);
    border-color: transparent;
    background-color: #029fcb;
}

table,
tr,
td {
    border: 1px solid black;
}

table {
    border-collapse: collapse;
    margin: 25px auto 0;
    background: #fff;
}

tr {
    height: 20px;
}

td {
    width: 20px;
}