styles.css

body {
    background-color: #52D99F;
    font-family: roboto;
    text-align: center;
    margin: 10px auto;
}

a {
    text-decoration: none;
}

td a:not([href]) {
    cursor: not-allowed;
}

td a[href]:hover{
    animation: clickme 0.8s infinite;
}

td a {
    color: white;
    display: block;
    width: 25vmin;
    font-size: 25vmin;
}

td {
    margin: 0;
    padding: 0; 
    background-color: #58007D;
}

table {
    background-color: #FFFFFF;
    border-collapse: collapse;
    vertical-align: middle;
    text-align: center;
    border-spacing: 0;
    margin: 10px auto;
    max-width: 600px;
}

.border {
    border-style: solid;
    border-width: 5px;
    border-color: white;
    background-color: #C259FF;
}

#foo, #z {
    border-top: 0;
    border-bottom: 0;
}

#bar, #baz {
    border-right: 0;
    border-left: 0;
}

@keyframes clickme {
    0%,100% {background-color: rgba(0,0,0,0);}
    50% {background-color: rgba(255,255,255,0.64);}
}

.button {
    margin: 8px;
    padding: 16px;
    color: white;
    border-radius: 16px;
    background-color: #58007D;
}

.button:hover {
    opacity: 0.75;
}