* {
    box-sizing: border-box;
}
html,
body {
    margin: 0;
    padding: 0;
    width: 100%;
    height: 100%;
    overflow: hidden;
    background: #222;
}
body {
    font-family: Arial, sans-serif;
}
#viewer {
    position: relative;
    width: 100%;
    height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
}
#book {
    margin: auto;
}
.page {
    position: relative;
    background: #fff;
    overflow: hidden;
}
.page canvas {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: block;
    object-fit: contain;
    background: #fff;
}
.xSlider {
    --side-pad: 20px;
    --card-gap: 16px;
    --card-width: calc(100vw - var(--side-pad) - var(--side-pad) - 28px);
    display: none;
    width: 100%;
    overflow: hidden;
    padding: 0 var(--side-pad);
}
.xSlider .slide {
    display: flex;
    gap: var(--card-gap);
    margin: 0 calc(-1 * var(--side-pad));
    overflow-x: auto;
    scrollbar-width: none;
    -ms-overflow-style: none;
    padding: 0 var(--side-pad) 8px;
    scroll-padding-inline: var(--side-pad);
    -webkit-overflow-scrolling: touch;
    overscroll-behavior-x: contain;
}
.xSlider .slide.smooth {
    scroll-snap-type: x mandatory;
    scroll-behavior: smooth;
}
.xSlider .slide::-webkit-scrollbar {
    display: none;
}
.xSlider .slide > .page {
    flex: 0 0 auto;
    width: min(var(--card-width), calc((100vh - 100px) * var(--page-ratio, 0.707)));
    aspect-ratio: var(--page-ratio, 3 / 4);
    max-height: calc(100vh - 100px);
    scroll-snap-align: start;
    scroll-snap-stop: always;
    border-radius: 7px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.25);
}
.xSlider .slide > .page:last-child {
    scroll-snap-align: end;
}
body.is-mobile #book,
body.is-desktop .xSlider {
    display: none;
}
body.is-mobile .xSlider {
    display: block;
}
.controls {
    position: fixed;
    left: 50%;
    bottom: 20px;
    transform: translateX(-50%);
    display: flex;
    align-items: center;
    gap: 8px;
    z-index: 99999;
}
.controls button {
    min-width: 44px;
    height: 40px;
    padding: 0 12px;
    border: 0;
    border-radius: 5px;
    background: rgba(255, 255, 255, 0.95);
    color: #222;
    font-size: 20px;
    cursor: pointer;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.25);
}
.controls button:hover {
    background: #fff;
}
.controls button.disabled {
    opacity: 0.4;
    cursor: default;
    pointer-events: none;
}
.page-info {
    min-width: 80px;
    padding: 0 10px;
    text-align: center;
    color: #fff;
    font-size: 14px;
}
.loading {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    color: #fff;
    font-size: 18px;
    z-index: 100000;
}
@media (max-width: 768px) {
    .controls {
        bottom: 10px;
    }
    .controls button {
        min-width: 40px;
        height: 38px;
    }
}