amercier/rectangular-mozaic

html {
    display: flex;
    align-items: center;
    justify-content: center;
    font-family: Roboto;
    text-align: center;
    min-height: 100%;
}

a {
    display: block;
    margin: 2rem auto 1rem;
    color: inherit;
    text-decoration: none;
}

h1 {
    font-weight: 100;
}

table {
    border-spacing: 5px;
    border-collapse: separate;
    margin-left: auto;
    margin-right: auto;
}

table:hover {
    background-color: #fff176;
}

tr {
    height: 3rem;
}

td {
    background-color: #43a047;
    min-width: 4rem;
}

td[colspan] {
    background-color: #1976d2;
    color: #fff;
}

td[rowspan] {
    background-color: #d81b60;
    color: #fff;
}