body {
    font-family: Arial, Helvetica, sans-serif;
    text-align: center;
    background-color: hsl(0, 0%, 50%);
}

.back-to-home {
    text-decoration: none;
    font-size: 1.5rem;
    font-weight: bold;
    color: hsl(0, 0%, 100%);
    margin: 10px 5px;
}

.back-to-home:is(:hover, :focus) {
    color: hsl(0, 0%, 0%);
}

hr {
    width: 500px;
}

#board {
    width: 400px;
    height: 400px;
    background-color: hsl(30, 19%, 76%);
    border: 6px solid hsl(29, 17%, 68%);
    margin: 0 auto;
    display: flex;
    flex-wrap: wrap;
}

.tile {
    width: 90px;
    height: 90px;
    border: 5px solid hsl(29, 17%, 68%);
    font-size: 40px;
    font-weight: bold;
    display: flex;
    justify-content: center;
    align-items: center;
}

.x2 {
    background-color: hsl(30, 37%, 89%);
    color: hsl(90, 1%, 45%);
}

.x4 {
    background-color: hsl(39, 47%, 86%);
    color: hsl(90, 1%, 45%);
}

.x8 {
    background-color: hsl(27, 85%, 72%);
    color: hsl(0, 0%, 100%);
}

.x16 {
    background-color: hsl(15, 86%, 71%);
    color: hsl(0, 0%, 100%);
}

.x32 {
    background-color: hsl(12, 88%, 67%);
    color: hsl(0, 0%, 100%);
}

.x64 {
    background-color: hsl(11, 91%, 60%);
    color: hsl(0, 0%, 100%);
}

.x128 {
    background-color: hsl(45, 78%, 69%);
    color: hsl(0, 0%, 100%);
}

.x256 {
    background-color: hsl(46, 79%, 66%);
    color: hsl(0, 0%, 100%);
}

.x512 {
    background-color: hsl(45, 81%, 62%);
    color: hsl(0, 0%, 100%);
}

.x1024 {
    background-color: hsl(46, 83%, 60%);
    color: hsl(0, 0%, 100%);
}

.x2048 {
    background-color: hsl(47, 83%, 56%);
    color: hsl(0, 0%, 100%);
}

.x4096 {
    background-color: hsl(0, 99%, 62%);
    color: hsl(0, 0%, 100%);
}

.x8192 {
    background-color: hsl(0, 100%, 56%);
    color: hsl(0, 0%, 100%);
}