.gallery {
    position: relative;
    overflow: hidden;
    display: block;
    -moz-user-select: -moz-none;
    -khtml-user-select: none;
    -webkit-user-select: none;
    -o-user-select: none;
    user-select: none;
}

.gallery_nav_button {
    width: 26px;
    height: 48px;
    position: absolute;
    cursor: pointer;
    opacity: 0.8;
    top: 50%;
    transform: translate(0,-50%);
}

.gallery_nav_button:hover {
    opacity: 1.0;
}

.gallery_nav_button.next {
    background-image: url('data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABoAAAAwCAYAAAAPfWqeAAAAAXNSR0IArs4c6QAAAL9JREFUWAntmNEJhDAQRMUOzkrsyPvSNizNBrQjyb2IQpBECLqK3CwMRoMZ8nYNiUWxhnOuRZ/t3uSKQY98jMjGjIFrNKMtJhpmZl8GD81MZyaz84VJvoRRGNMEni6QW5crb1alWZzoiWCUWT5PYcxnFnnjrzAOZYTAOx6RpwaFO6rrVw2ZZBWDcAkXNbCEPsZ0LQCoQVq70ojCnrtw7U97JiUskzC1x20SH/tFY3YM6TH0cX3i9/PEpEM2M8HsB0bJ3vgeR/bbAAAAAElFTkSuQmCC');
    right: 13px;
}

.gallery_nav_button.prev {
    background-image: url('data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABoAAAAwCAYAAAAPfWqeAAAAAXNSR0IArs4c6QAAAM9JREFUWAntmEEOAiEMRSfeQE/ijWSl15ijeQG9kcHf2G4mpSkEXH0SQlJKH30LJpltWzRqrWfM+6Lyv7IKeWGVsS+BobB08haCjg/W61QYCgrEOhGOQAohrgGooS7XjBukLldLK/hPXcdnpbQuNRRHJxdMQnL2qCvnSbOoq0uXJEPZE9PG/G+83ujUfbPRA2jFe2Juo/XCc4SFerKb1Jg1FeZRY6gnu0mNWVNhHjWGerKbDY0le74rj7AuXa3khsa5v2gMfoDtFl+yKuxhxb9N+d74fx4WvAAAAABJRU5ErkJggg==');
    left: 13px;
}

.gallery_item {
    top: 0;
    left: 0;
    display: inline-block;
    text-align: center;
}

.gallery_item img, iframe {
    vertical-align: middle;
    margin: 0 auto;
}