h1 {
    text-align: center;
}

#unit-label {
    display: inline;
    text-align: center;
}

.birthday {
    margin: 0 auto 0 auto;
    width:250px;
}

.day { width: 3em; }
.year { width: 4em; }
.canvas {
    border: 2px solid black;
    margin: 0 auto 0 auto;
    width: 500px;
    height: 800px;
}
#canvas {
    width: 500px;
    height: 800px;
}