/* wrapper */
.pdf-flipbook-wrapper {
    background: #f6f6f6;
    border-radius: 6px;
    padding: 0;
    box-shadow: 0 6px 30px rgba(0,0,0,0.12);
    overflow: visible;
    aspect-ratio: 420 / 297;
}

/* toolbar */
.pdf-flipbook-toolbar {
    text-align: center;
    margin-bottom: 8px;
}
.pdf-flipbook-toolbar button {
    margin: 0 6px;
    padding: 6px 10px;
    border-radius: 4px;
    border:none;
    background: #fff;
    cursor: pointer;
    font-size: 14px;
}
.pdf-flipbook-toolbar button:hover { background:#f0f0f0; }

/* stage holds the book (with perspective) */
.pdf-flipbook-stage {
    position: relative;
    width: 100%;
    height: 100% !important;
    background: linear-gradient(180deg,#fff,#fafafa);
    overflow: hidden;
    display: flex;
    justify-content: center;
    align-items: center;
    transition: transform 0.15s ease;
}

/* turn.js pages */
.pdf-flipbook .page {
    background: #fff;
    box-shadow: 0 6px 20px rgba(0,0,0,0.2);
    border:none;
    overflow: hidden;
}
.pdf-flipbook .page .page-inner {
    width: 100%;
    height: 100%;
    position: relative;
}
.pdf-flipbook .page img {
    display: block;
    width: 100%;
    height: 100%;
    object-fit: cover;
}

/* cover/back-cover special style */
.pdf-flipbook .cover { background: linear-gradient(180deg,#eee,#ddd); }
.pdf-flipbook .back-cover { background: linear-gradient(180deg,#ddd,#bbb); }

/* small screens: make it single page */
@media (max-width: 700px) {
    .pdf-flipbook .page { box-shadow: none; border: none; }
}