html, body {
    margin: 0;
    height: 100%;
}

body {
    background-color: #333;
}

body.hide-overflow {
    overflow: hidden;
}

/* helpers */
.t {
    display: table;
    width: 100%;
    height: 100%;
}

.tc {
    display: table-cell;
    vertical-align: middle;
    text-align: center;
}

.rel {
    position: relative;
}

.tc .loader{
    background-image: url(../img/loader.gif);
    width: 22px;
    height: 22px;
    position: absolute;
    top: 200px;
    left: 219px;
}

/* book */

.book {
    margin: 0 auto;
    width: 90%;
    height: 90%;
    -webkit-touch-callout: none;
    -webkit-user-select: none;
    -khtml-user-select: none;
    -moz-user-select: none;
    -ms-user-select: none;
    user-select: none;
}

.book .page {
    height: 100%;
    background-color: white;
}

.book .page img {
    max-width: 100%;
}

#download-btn {
    position: absolute;
    left: 0;
    right: 0;
    bottom: -1px;
    text-align: center;
}

#download-btn a {
    display: inline-block;
    color: #C00;
    background: #FFF;
    font: 12px/14px sans-serif;
    text-decoration: none;
    padding: 1em 2em;
    border: solid 1px #C00;
    font-weight: bold;
}