.uifb {
    --uifb-height: 78vh;
    --uifb-bg: #777;
    --uifb-toolbar-bg: #242424;
    --uifb-toolbar-fg: #f6f6f6;
    --uifb-accent: rgba(255,255,255,.15);
    width: 100%;
    min-height: 420px;
    height: var(--uifb-height);
    background: var(--uifb-bg);
    display: flex;
    flex-direction: column;
    overflow: hidden;
    border-radius: 2px;
    box-shadow: 0 2px 12px rgba(0,0,0,.12);
    position: relative;
    isolation: isolate;
    font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}
.uifb:focus { outline: 2px solid rgba(255,255,255,.45); outline-offset: 2px; }
.uifb * { box-sizing: border-box; }
.uifb-toolbar {
    min-height: 48px;
    padding: 6px 10px;
    background: var(--uifb-toolbar-bg);
    color: var(--uifb-toolbar-fg);
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
    z-index: 30;
    box-shadow: 0 2px 8px rgba(0,0,0,.18);
}
.uifb-toolbar-group { display: flex; align-items: center; gap: 4px; min-width: 0; }
.uifb-btn {
    appearance: none;
    border: 0;
    background: transparent;
    color: inherit;
    width: 36px;
    height: 34px;
    border-radius: 4px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    text-decoration: none !important;
    font-size: 21px;
    line-height: 1;
    cursor: pointer;
    padding: 0;
}
.uifb-btn:hover, .uifb-btn:focus-visible { background: var(--uifb-accent); outline: none; }
.uifb-btn:disabled { opacity: .35; cursor: default; }
.uifb-page-indicator, .uifb-zoom-label {
    font-size: 13px;
    white-space: nowrap;
    min-width: 66px;
    text-align: center;
    opacity: .95;
}
.uifb-zoom-label { min-width: 46px; }
.uifb-main { display: flex; flex: 1; min-height: 0; position: relative; }
.uifb-thumbs {
    width: 0;
    flex: 0 0 0;
    overflow: hidden auto;
    background: rgba(30,30,30,.96);
    transition: width .22s ease, flex-basis .22s ease;
    padding: 0;
    z-index: 20;
}
.uifb.is-thumbs-open .uifb-thumbs {
    width: 170px;
    flex-basis: 170px;
    padding: 10px;
}
.uifb-thumb {
    display: block;
    width: 100%;
    border: 0;
    border-radius: 4px;
    background: rgba(255,255,255,.07);
    color: #fff;
    margin: 0 0 10px;
    padding: 6px;
    cursor: pointer;
    text-align: center;
}
.uifb-thumb:hover, .uifb-thumb.is-active { background: rgba(255,255,255,.18); }
.uifb-thumb canvas { max-width: 100%; height: auto; background: white; display: block; margin: 0 auto 5px; }
.uifb-thumb span { font-size: 12px; }
.uifb-stage { flex: 1; min-width: 0; min-height: 0; position: relative; overflow: hidden; }
.uifb-scroll {
    position: absolute;
    inset: 0;
    overflow: auto;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 28px 58px;
    scrollbar-width: thin;
}
.uifb-book {
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 2px;
    width: max-content;
    min-width: 0;
    transform-style: preserve-3d;
    perspective: 1800px;
}
.uifb-page {
    position: relative;
    flex: 0 0 auto;
    background: #fff;
    box-shadow: 0 4px 22px rgba(0,0,0,.34);
    overflow: hidden;
    backface-visibility: hidden;
}
.uifb-page.uifb-left { box-shadow: -5px 4px 22px rgba(0,0,0,.28); }
.uifb-page.uifb-right { box-shadow: 5px 4px 22px rgba(0,0,0,.28); }
.uifb-page canvas { display: block; width: 100%; height: 100%; }
.uifb-page.is-blank { background: transparent; box-shadow: none; visibility: hidden; }
.uifb-book::after {
    content: "";
    position: absolute;
    left: 50%;
    top: 0;
    bottom: 0;
    width: 12px;
    transform: translateX(-50%);
    pointer-events: none;
    background: linear-gradient(90deg, rgba(0,0,0,.10), rgba(255,255,255,.08) 45%, rgba(0,0,0,.12));
    opacity: .7;
    z-index: 5;
}
.uifb.is-single .uifb-book::after { display: none; }
.uifb-turn-sheet {
    position: absolute;
    z-index: 15;
    background: #fff;
    pointer-events: none;
    transform-style: preserve-3d;
    backface-visibility: hidden;
    box-shadow: 0 5px 25px rgba(0,0,0,.35);
    transition: transform .48s cubic-bezier(.2,.65,.3,1), filter .48s ease;
}
.uifb-turn-sheet canvas { width: 100%; height: 100%; display: block; }
.uifb-turn-sheet.turn-next { transform-origin: left center; transform: rotateY(0deg); }
.uifb-turn-sheet.turn-next.is-active { transform: rotateY(-178deg); filter: brightness(.88); }
.uifb-turn-sheet.turn-prev { transform-origin: right center; transform: rotateY(0deg); }
.uifb-turn-sheet.turn-prev.is-active { transform: rotateY(178deg); filter: brightness(.88); }
.uifb-side-nav {
    position: absolute;
    z-index: 25;
    top: 50%;
    transform: translateY(-50%);
    width: 46px;
    height: 72px;
    border: 0;
    border-radius: 4px;
    background: rgba(0,0,0,.22);
    color: #fff;
    font-size: 42px;
    line-height: 1;
    cursor: pointer;
    opacity: .78;
}
.uifb-side-nav:hover { opacity: 1; background: rgba(0,0,0,.38); }
.uifb-side-nav:disabled { opacity: .18; cursor: default; }
.uifb-side-prev { left: 9px; }
.uifb-side-next { right: 9px; }
.uifb-loading {
    position: absolute;
    inset: 0;
    z-index: 40;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 12px;
    background: rgba(0,0,0,.18);
    color: #fff;
    font-size: 14px;
    transition: opacity .18s ease;
}
.uifb.is-ready .uifb-loading { opacity: 0; pointer-events: none; }
.uifb-spinner {
    width: 36px;
    height: 36px;
    border: 4px solid rgba(255,255,255,.3);
    border-top-color: #fff;
    border-radius: 50%;
    animation: uifb-spin .8s linear infinite;
}
@keyframes uifb-spin { to { transform: rotate(360deg); } }
.uifb-message {
    position: absolute;
    z-index: 50;
    left: 50%; top: 50%; transform: translate(-50%,-50%);
    max-width: 520px;
    padding: 14px 18px;
    border-radius: 5px;
    background: rgba(25,25,25,.92);
    color: #fff;
    text-align: center;
}
.uifb.is-fullscreen { height: 100vh !important; border-radius: 0; }
.uifb-error { padding: 12px 14px; border-left: 4px solid #d63638; background: #fff4f4; }

@media (max-width: 760px) {
    .uifb { min-height: 360px; height: min(var(--uifb-height), 78vh); }
    .uifb-toolbar { padding: 5px 6px; gap: 4px; }
    .uifb-btn { width: 31px; height: 32px; font-size: 19px; }
    .uifb-toolbar .uifb-first, .uifb-toolbar .uifb-last, .uifb-toolbar .uifb-fit { display: none; }
    .uifb-page-indicator { min-width: 56px; font-size: 12px; }
    .uifb-zoom-label { display: none; }
    .uifb-scroll { padding: 18px 42px; }
    .uifb-side-nav { width: 34px; height: 58px; font-size: 34px; }
    .uifb-side-prev { left: 4px; }
    .uifb-side-next { right: 4px; }
    .uifb.is-thumbs-open .uifb-thumbs { position: absolute; inset: 0 auto 0 0; width: 155px; z-index: 35; }
}

/* Search panel */
.uifb-search-panel[hidden] { display: none !important; }
.uifb-search-panel {
    position: absolute;
    top: 52px;
    right: 10px;
    z-index: 45;
    display: flex;
    align-items: center;
    gap: 6px;
    min-width: min(520px, calc(100% - 20px));
    padding: 8px;
    border-radius: 5px;
    background: rgba(32,32,32,.97);
    color: #fff;
    box-shadow: 0 5px 18px rgba(0,0,0,.28);
}
.uifb-search-input {
    min-width: 180px;
    flex: 1 1 260px;
    height: 34px;
    padding: 6px 10px;
    border: 1px solid rgba(255,255,255,.24);
    border-radius: 4px;
    background: #fff;
    color: #1d2327;
    font: inherit;
    font-size: 14px;
    outline: none;
}
.uifb-search-input:focus {
    border-color: rgba(255,255,255,.8);
    box-shadow: 0 0 0 2px rgba(255,255,255,.16);
}
.uifb-search-status {
    flex: 0 0 auto;
    max-width: 190px;
    font-size: 12px;
    line-height: 1.25;
    opacity: .92;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}
.uifb-search-nav,
.uifb-search-close {
    appearance: none;
    border: 0;
    width: 32px;
    height: 32px;
    border-radius: 4px;
    background: rgba(255,255,255,.08);
    color: #fff;
    cursor: pointer;
    font-size: 18px;
    line-height: 1;
    padding: 0;
}
.uifb-search-nav:hover,
.uifb-search-close:hover,
.uifb-search-nav:focus-visible,
.uifb-search-close:focus-visible { background: rgba(255,255,255,.18); outline: none; }
.uifb-search-nav:disabled { opacity: .32; cursor: default; }
.uifb-search-toggle[aria-expanded="true"] { background: var(--uifb-accent); }

@media (max-width: 760px) {
    .uifb-search-panel {
        top: 48px;
        left: 6px;
        right: 6px;
        min-width: 0;
        width: auto;
        gap: 4px;
        padding: 6px;
    }
    .uifb-search-input { min-width: 0; flex-basis: 140px; }
    .uifb-search-status { max-width: 92px; font-size: 11px; }
    .uifb-search-nav, .uifb-search-close { width: 29px; height: 30px; }
}