h1, p {
    text-align: center;
}

#kalenteri {
    position: relative;
    width: 725px;
    height: 1000px;
    margin-left: auto;
    margin-right: auto;
    background-color: #eee;
    background-image: url('kalenteri_pohja.jpg');
    background-size: contain;
    border-style: solid;
}

.luukku {
    position: absolute;
    padding: 30px;
    font-weight: bold;
    font-size: 1.3em;
    width: 40px;
    height: 40px;
    background-color: rgba(170, 187, 204, 0.3);
    background-size: contain;
    background-repeat: no-repeat;
    background-position: center;
    border-style: outset;
    border-width: 2px;
    color: white;
    text-shadow: -1px 0 black, 0 1px black, 1px 0 black, 0 -1px black;
}

.luukku.auki {
    background-color: rgba(170, 187, 204, 1.0);
    font-size: 0;
}

#luukku24 {
    padding: 40px;
    width: 50px;
    height: 50px;
}