/* PDF Viewer - Modern Turn.js implementation */
:root {
    --viewer-bg: #2a2a2a;
    --viewer-shadow: rgba(0, 0, 0, 0.3);
    --page-bg: #fff;
    --control-bg: rgba(0, 0, 0, 0.6);
    --control-hover: rgba(0, 0, 0, 0.8);
    --thumbnail-border: #666;
    --thumbnail-active: #007bff;
}

#pdf-viewer-container {
    position: relative;
    width: 100%;
    height: 700px;
    background: var(--viewer-bg);
    overflow: hidden;
    margin-bottom: 2rem;
    border-radius: 8px;
}

/* Magazine Viewport */
.magazine-viewport {
    position: relative;
    width: 100%;
    height: 100%;
    overflow: hidden;
}

.magazine-viewport .container {
    position: absolute;
    top: 50%;
    left: 50%;
    margin: auto;
}

.magazine-viewport .magazine {
    box-shadow: 0 0 20px var(--viewer-shadow);
}

/* Animated margin transition for autoCenter */
.magazine-viewport .animated {
    -webkit-transition: margin-left 0.5s;
    -moz-transition: margin-left 0.5s;
    -ms-transition: margin-left 0.5s;
    -o-transition: margin-left 0.5s;
    transition: margin-left 0.5s;
}

/* Page styles */
.magazine-viewport .page {
    overflow: hidden;
    background-color: white;
    background-repeat: no-repeat;
    background-size: 100% 100%;
}

.magazine .page {
    -webkit-box-shadow: 0 0 20px rgba(0,0,0,0.2);
    -moz-box-shadow: 0 0 20px rgba(0,0,0,0.2);
    box-shadow: 0 0 20px rgba(0,0,0,0.2);
}

.magazine-viewport .page img {
    display: block;
    -webkit-touch-callout: none;
    -webkit-user-select: none;
    -moz-user-select: none;
    -ms-user-select: none;
    user-select: none;
    margin: 0;
}

/* Page gradient overlays */
.magazine .even .gradient {
    position: absolute;
    top: 0; left: 0;
    width: 100%; height: 100%;
    background-image: linear-gradient(to right, rgba(0,0,0,0) 95%, rgba(0,0,0,0.2) 100%);
}

.magazine .odd .gradient {
    position: absolute;
    top: 0; left: 0;
    width: 100%; height: 100%;
    background-image: linear-gradient(to left, rgba(0,0,0,0) 95%, rgba(0,0,0,0.15) 100%);
}

/* Hide gradients when zoomed in */
.magazine-viewport .zoom-in .even .gradient,
.magazine-viewport .zoom-in .odd .gradient {
    display: none;
}

/* Hide nav buttons when zoomed */
.magazine-viewport .zoom-in .next-button,
.magazine-viewport .zoom-in .previous-button {
    display: none;
}

/* Zoomer clone overlay */
.magazine-viewport .zoomer {
    overflow: hidden;
    position: absolute;
    z-index: 1000000;
}

/* Navigation Buttons */
.nav-button {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    width: 50px;
    height: 80px;
    background: var(--control-bg);
    border: none;
    color: white;
    font-size: 24px;
    cursor: pointer;
    z-index: 1000;
    transition: background 0.3s;
    border-radius: 8px;
}

.nav-button:hover {
    background: var(--control-hover);
}

.nav-button:disabled {
    opacity: 0.3;
    cursor: not-allowed;
}

.nav-button.previous {
    left: 20px;
}

.nav-button.next {
    right: 20px;
}

/* Zoom Controls */
.zoom-controls {
    position: absolute;
    top: 20px;
    right: 20px;
    z-index: 1000;
    display: flex;
    gap: 10px;
}

.zoom-btn {
    width: 40px;
    height: 40px;
    background: var(--control-bg);
    border: none;
    color: white;
    font-size: 18px;
    cursor: pointer;
    border-radius: 4px;
    transition: background 0.3s;
}

.zoom-btn:hover {
    background: var(--control-hover);
}

/* Thumbnails */
.thumbnails {
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 150px;
    background: rgba(0, 0, 0, 0.8);
    z-index: 999;
    overflow-x: auto;
    overflow-y: hidden;
    display: none;
}

.thumbnails.visible {
    display: block;
}

.thumbnails-container {
    display: flex;
    gap: 10px;
    padding: 20px;
    align-items: center;
}

.thumbnail {
    flex-shrink: 0;
    width: 100px;
    height: 100px;
    cursor: pointer;
    border: 2px solid var(--thumbnail-border);
    transition: all 0.3s;
    border-radius: 4px;
    overflow: hidden;
}

.thumbnail img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.thumbnail:hover {
    transform: scale(1.1);
    box-shadow: 0 0 10px rgba(255, 255, 255, 0.5);
}

.thumbnail.active {
    border-color: var(--thumbnail-active);
    box-shadow: 0 0 15px var(--thumbnail-active);
}

/* Page Counter */
.page-counter {
    position: absolute;
    bottom: 20px;
    left: 50%;
    transform: translateX(-50%);
    background: var(--control-bg);
    color: white;
    padding: 8px 16px;
    border-radius: 20px;
    font-size: 14px;
    z-index: 1001;
    transition: bottom 0.3s;
}

/* Move page counter up when thumbnails are visible */
.thumbnails.visible ~ .page-counter {
    bottom: 160px;
}

/* Main Viewer Loader */
.viewer-loader {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 50px;
    height: 50px;
    border: 5px solid rgba(255, 255, 255, 0.3);
    border-top-color: white;
    border-radius: 50%;
    animation: spin 1s linear infinite;
    z-index: 100;
}

/* Page-level loader (inside Turn.js pages) */
.magazine .page .loader {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 22px;
    height: 22px;
    border: 3px solid rgba(0, 0, 0, 0.1);
    border-top-color: #999;
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

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

/* Responsive */
@media (max-width: 768px) {
    .nav-button {
        width: 40px;
        height: 60px;
        font-size: 18px;
    }
    
    .thumbnails {
        height: 100px;
    }
    
    .thumbnail {
        width: 70px;
        height: 70px;
    }
}