* {
    margin: 0;
    padding: 0;
}

body {
    text-align: center;
}

#reset {
    height: 2em;
    width: auto;
}

#cases {
    border-collapse: collapse;
    margin: auto;
}
#cases td {
    background-color: #ddd; 
    border: 1px solid black;
    width: 2em;
    height: 2em;
    text-align: center;
    font-weight: bold;
}
#cases form, #cases input {
    width: 100%;
    height: 100%;
}
#cases input {
    border: 4px outset grey;
    box-sizing: border-box;
}