.ws-pdf-viewer {
    border: 1px solid #d6d6d6;
    padding: 12px;
    max-width: 980px;
    margin: 20px auto;
    background: #fafafa;
    --ws-pdf-nav-bg: #ffffff;
    --ws-pdf-nav-border: #bbb;
    --ws-pdf-nav-color: #111;
}

.ws-pdf-viewer__canvas-wrap {
    position: relative;
    display: flex;
    justify-content: center;
    align-items: center;
    overflow: hidden;
    padding: 0 0;
    background: #fff;
    max-height: var(--ws-pdf-max-height, 80vh);
}

.ws-pdf-viewer__spread {
    display: flex;
    align-items: center;
    gap: 12px;
}

.ws-pdf-viewer__nav {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    border: 1px solid var(--ws-pdf-nav-border);
    background: var(--ws-pdf-nav-bg);
    color: var(--ws-pdf-nav-color);
    padding: 8px 12px;
    cursor: pointer;
    font-size: 18px;
    line-height: 1;
    z-index: 2;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.2s ease, transform 0.2s ease;
}

.material-symbols-rounded {
    font-variation-settings: 'FILL' 0, 'wght' 400, 'GRAD' 0, 'opsz' 24;
    font-size: 22px;
    line-height: 1;
    display: inline-block;
    vertical-align: middle;
}

.ws-pdf-viewer__nav--prev {
    left: 8px;
    transform: translate(-6px, -50%);
}

.ws-pdf-viewer__nav--next {
    right: 8px;
    transform: translate(6px, -50%);
}

.ws-pdf-viewer__nav:focus-visible {
    outline: 2px solid #0073aa;
    outline-offset: 2px;
}

.ws-pdf-viewer__canvas-wrap:hover .ws-pdf-viewer__nav,
.ws-pdf-viewer__canvas-wrap:focus-within .ws-pdf-viewer__nav {
    opacity: 1;
    pointer-events: auto;
    transform: translate(0, -50%);
}

.ws-pdf-viewer__nav:disabled {
    opacity: 0;
    pointer-events: none;
}

.ws-pdf-viewer--nav-round .ws-pdf-viewer__nav {
    border-radius: 999px;
}

.ws-pdf-viewer--nav-square .ws-pdf-viewer__nav {
    border-radius: 4px;
}

.ws-pdf-viewer__canvas {
    max-width: 100%;
    height: auto;
    max-height: var(--ws-pdf-max-height, 80vh);
}

.ws-pdf-viewer__thumbs {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
    justify-content: center;
    align-items: flex-start;
    padding-top: 12px;
}

.ws-pdf-viewer__thumb {
    border: 1px solid #ccc;
    background: #fff;
    padding: 4px;
    cursor: pointer;
    position: relative;
    min-height: 60px;
    width: 72px;
}

.ws-pdf-viewer__thumb.is-active {
    outline: 2px solid #0073aa;
}

.ws-pdf-viewer__thumb.is-loading img {
    display: none;
}

.ws-pdf-viewer__thumb.is-loading::after {
    content: "";
    position: absolute;
    width: 18px;
    height: 18px;
    border: 2px solid #d0d7de;
    border-top-color: #2271b1;
    border-radius: 50%;
    animation: ws-pdf-viewer-thumb-spin 0.8s linear infinite;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
}

@keyframes ws-pdf-viewer-thumb-spin {
    to { transform: translate(-50%, -50%) rotate(360deg); }
}

.ws-pdf-viewer__thumb canvas {
    width: 100%;
    height: auto;
    display: block;
}

.ws-pdf-viewer__thumb-label {
    display: block;
    margin-top: 4px;
    font-size: 11px;
    text-align: center;
    color: #555;
}

.ws-pdf-viewer__thumb-sep {
    align-self: center;
    padding: 0 4px;
    color: #777;
    font-weight: 600;
}

.ws-pdf-viewer__thumb-note {
    grid-column: 1 / -1;
    font-size: 12px;
    color: #666;
    text-align: center;
}

@media (max-width: 600px) {
    .ws-pdf-viewer {
        padding: 8px;
    }

    .ws-pdf-viewer__nav {
        padding: 6px 10px;
    }

    .ws-pdf-viewer--mode-flip .ws-pdf-viewer__nav {
        display: none;
    }

    .ws-pdf-viewer__thumbs {
        gap: 6px;
        flex-wrap: nowrap;
        overflow-x: auto;
        justify-content: flex-start;
        -webkit-overflow-scrolling: touch;
    }

    .ws-pdf-viewer__thumb {
        width: calc((100% - 18px) / 4) !important;
        min-width: 0;
        flex: 0 0 calc((100% - 18px) / 4) !important;
        max-width: calc((100% - 18px) / 4);
        padding: 3px;
    }
}

@media (max-width: 360px) {
    .ws-pdf-viewer__thumb {
        width: calc((100% - 12px) / 3) !important;
        flex: 0 0 calc((100% - 12px) / 3) !important;
        max-width: calc((100% - 12px) / 3);
    }
}