html, body {
    font-family: Arial;
    margin: 0 auto;
    width: 30em;
    min-width: 30em;
    height: 100%;
    text-align: center;
}

#sudoku_container {
    display: block;
    text-align: center;
    margin: 3em 0 3em 0;
}

.button {
    padding: 0 0.5em 0 0.5em;
    height: 1.333em;
    line-height: 1.333em;
    text-align: center;
    background-color: #EEEEEE;
    border: 0.05em solid #000000;
    border-radius: 0.2em;
    display: inline-block;
    font-size: 3em;
    margin: 0.1em;
}

.text {
    font-size: 2em;
}

.button:hover {
    background-color: #BBBBFF;
    cursor: pointer;
}

.sudoku_board {
    border: 0.1em solid #000000;
    display: inline-block;
    max-width: auto;
}

.sudoku_board_block {
    float: left;
    background-color: #000000;
    border: 0.05em solid #000000;
}

.sudoku_board_box {
    background-color: #EEEEEE;
    border: 0.01em solid #999999;
    float: left;
    width: 1em;
    height: 1em;
    font-size: 3em;
    text-align: center;
    line-height: 1em;
}

.sudoku_board_box:hover {
    background-color: #BBBBFF;
    cursor: pointer;
}

.sudoku_pencil_mark {
    float: left;
    width: 33.333%;
    height: 1.111em;
    line-height: 1em;
    font-size: 0.3em;
    color: #444444;
}

.grey {
    background-color: #DDDDDD;
}

@media screen and (max-height: 1000px) {
    html, body {
        width: auto;
        min-width: auto;
    }
    #sudoku_container {
        margin: 0;
    }
}