/* Lightbox - vlastni prohlizec obrazku a PDF (nahrada Fancybox) */
.lb {
    --lb-bg: rgba(24, 24, 27, 0.94);
    --lb-fg: #f4f4f5;
    --lb-muted: rgba(244, 244, 245, 0.7);
    --lb-btn-bg: rgba(24, 24, 27, 0.55);
    --lb-btn-hover: rgba(70, 70, 76, 0.85);
    --lb-accent: #f4f4f5;
    --lb-fade: 1;
    --lb-thumbs-h: 0px;
    position: fixed;
    inset: 0;
    z-index: 100000;
    display: flex;
    flex-direction: column;
    color: var(--lb-fg);
    font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
    font-size: 15px;
    line-height: 1.4;
    opacity: 0;
    transition: opacity 0.2s ease;
    outline: none;
    -webkit-tap-highlight-color: transparent;
    user-select: none;
    -webkit-user-select: none;
}
.lb *, .lb *::before, .lb *::after { box-sizing: border-box; }
.lb--open { opacity: 1; }
.lb--closing { opacity: 0; pointer-events: none; }
.lb--thumbs { --lb-thumbs-h: 84px; }

.lb__backdrop {
    position: absolute;
    inset: 0;
    background: var(--lb-bg);
    opacity: var(--lb-fade);
}

/* Horni lista */
.lb__toolbar {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    z-index: 3;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 8px;
    pointer-events: none;
}
.lb__toolbar > * { pointer-events: auto; }
.lb__counter {
    padding: 0 10px;
    font-size: 14px;
    font-variant-numeric: tabular-nums;
    color: var(--lb-muted);
}
.lb__tools { display: flex; gap: 4px; margin-left: auto; }

.lb__btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 44px;
    height: 44px;
    margin: 0;
    padding: 0;
    border: 0;
    border-radius: 8px;
    background: var(--lb-btn-bg);
    color: var(--lb-fg);
    cursor: pointer;
    transition: background-color 0.15s ease, opacity 0.15s ease;
}
.lb__btn:hover { background: var(--lb-btn-hover); }
.lb__btn:focus-visible { outline: 2px solid var(--lb-accent); outline-offset: 2px; }
.lb__btn[aria-pressed="true"] { background: var(--lb-btn-hover); }
.lb__btn:disabled { opacity: 0.3; cursor: default; }
.lb__btn svg { width: 22px; height: 22px; }

/* Ukazatel prubehu prezentace */
.lb__progress {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    z-index: 4;
    height: 3px;
    background: var(--lb-accent);
    transform: scaleX(0);
    transform-origin: 0 0;
    pointer-events: none;
}

/* Plocha se slidy */
.lb__stage {
    position: relative;
    z-index: 1;
    flex: 1 1 auto;
    min-height: 0;
    overflow: hidden;
    touch-action: none;
}
.lb__slide {
    position: absolute;
    inset: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 60px 64px 16px;
}
.lb__image {
    display: block;
    max-width: 100%;
    max-height: 100%;
    width: auto;
    height: auto;
    object-fit: contain;
    transform-origin: 50% 50%;
    opacity: 0;
    transition: opacity 0.2s ease;
    -webkit-user-drag: none;
}
.lb__slide--loaded .lb__image { opacity: 1; }
.lb--can-zoom .lb__image { cursor: zoom-in; }
.lb--zoomed .lb__image { cursor: grab; }
.lb--zoomed .lb__image:active { cursor: grabbing; }

.lb__frame {
    width: 100%;
    max-width: 1000px;
    height: 100%;
    background: #fff;
    border-radius: 4px;
    overflow: hidden;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.4);
}
.lb__frame iframe { display: block; width: 100%; height: 100%; border: 0; }

.lb__error {
    padding: 16px 24px;
    border-radius: 8px;
    background: var(--lb-btn-bg);
    color: var(--lb-fg);
}

.lb__spinner {
    position: absolute;
    top: 50%;
    left: 50%;
    width: 44px;
    height: 44px;
    margin: -22px 0 0 -22px;
    border: 3px solid rgba(255, 255, 255, 0.25);
    border-top-color: var(--lb-fg);
    border-radius: 50%;
    animation: lb-spin 0.8s linear infinite;
}
@keyframes lb-spin { to { transform: rotate(360deg); } }

/* Prechody mezi slidy */
.lb__slide--in-right { animation: lb-in-right 0.25s ease both; }
.lb__slide--in-left { animation: lb-in-left 0.25s ease both; }
.lb__slide--out-left { animation: lb-out-left 0.25s ease both; pointer-events: none; }
.lb__slide--out-right { animation: lb-out-right 0.25s ease both; pointer-events: none; }
@keyframes lb-in-right { from { opacity: 0; transform: translate3d(60px, 0, 0); } to { opacity: 1; transform: none; } }
@keyframes lb-in-left { from { opacity: 0; transform: translate3d(-60px, 0, 0); } to { opacity: 1; transform: none; } }
@keyframes lb-out-left { from { opacity: 1; } to { opacity: 0; transform: translate3d(-60px, 0, 0); } }
@keyframes lb-out-right { from { opacity: 1; } to { opacity: 0; transform: translate3d(60px, 0, 0); } }

/* Sipky */
.lb__nav {
    position: absolute;
    top: 50%;
    z-index: 3;
    width: 48px;
    height: 48px;
    margin-top: calc(-24px - var(--lb-thumbs-h) / 2);
    border-radius: 50%;
}
.lb__nav--prev { left: 8px; }
.lb__nav--next { right: 8px; }
.lb--zoomed .lb__nav { opacity: 0; pointer-events: none; }

/* Popisek */
.lb__caption {
    position: relative;
    z-index: 2;
    flex: 0 0 auto;
    max-height: 30vh;
    overflow-y: auto;
    padding: 4px 64px 12px;
    text-align: center;
    color: var(--lb-fg);
    user-select: text;
    -webkit-user-select: text;
}
.lb__caption[hidden] { display: none; }

/* Miniatury */
.lb__thumbs {
    position: relative;
    z-index: 2;
    flex: 0 0 auto;
    height: var(--lb-thumbs-h);
    overflow: hidden;
    transition: height 0.25s ease;
}
.lb__thumbs-track {
    display: flex;
    gap: 6px;
    height: 84px;
    padding: 8px 12px 12px;
    overflow-x: auto;
    overflow-y: hidden;
    scrollbar-width: thin;
}
.lb:not(.lb--thumbs) .lb__thumbs-track { visibility: hidden; }
.lb__thumbs-track::before,
.lb__thumbs-track::after { content: ""; flex: 1 0 0; }
.lb__thumb {
    flex: 0 0 auto;
    width: 64px;
    height: 64px;
    margin: 0;
    padding: 0;
    border: 2px solid transparent;
    border-radius: 6px;
    overflow: hidden;
    background: rgba(255, 255, 255, 0.08);
    color: var(--lb-fg);
    cursor: pointer;
    opacity: 0.55;
    transition: opacity 0.15s ease, border-color 0.15s ease;
}
.lb__thumb:hover { opacity: 0.85; }
.lb__thumb.is-active { opacity: 1; border-color: var(--lb-accent); }
.lb__thumb:focus-visible { outline: 2px solid var(--lb-accent); outline-offset: 1px; }
.lb__thumb img { display: block; width: 100%; height: 100%; object-fit: cover; pointer-events: none; }
.lb__thumb-label { display: flex; align-items: center; justify-content: center; height: 100%; font-size: 12px; font-weight: 600; }

@media (max-width: 640px) {
    .lb__slide { padding: 56px 8px 8px; }
    .lb__caption { padding: 4px 16px 10px; font-size: 14px; }
    .lb__nav { width: 40px; height: 40px; margin-top: calc(-20px - var(--lb-thumbs-h) / 2); }
    .lb__nav--prev { left: 4px; }
    .lb__nav--next { right: 4px; }
    .lb--thumbs { --lb-thumbs-h: 68px; }
    .lb__thumbs-track { height: 68px; padding: 6px 8px 10px; }
    .lb__thumb { width: 52px; height: 52px; }
}
@media (hover: none) {
    /* Na dotykovych zarizenich se listuje tahem, sipky jen prekazeji */
    .lb__nav { display: none; }
    .lb__slide { padding-left: 8px; padding-right: 8px; }
}

.lb--no-anim,
.lb--no-anim * { transition: none !important; animation-duration: 0.01ms !important; }
.lb--no-anim .lb__spinner { animation: lb-spin 1.5s linear infinite !important; }