* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Montserrat', sans-serif;
    background: linear-gradient(135deg, #1a1a1a, #2a2a2a);
    color: #333;
    overflow: hidden;
    height: 100vh;
}

.catalog-container {
    width: 100vw;
    height: 100vh;
    display: flex;
    flex-direction: column;
    position: relative;
}

/* Header */
.catalog-header {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    padding: 1rem 2rem;
    border-bottom: 2px solid #ffe066;
    z-index: 100;
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    max-width: 1400px;
    margin: 0 auto;
}

.logo img {
    height: 40px;
    filter: drop-shadow(0 2px 4px rgba(0, 0, 0, 0.1));
}

.catalog-header h1 {
    font-size: 1.8rem;
    font-weight: 700;
    color: #333;
    text-align: center;
    flex: 1;
}

.page-info {
    font-size: 1.2rem;
    font-weight: 600;
    color: #666;
    background: #f8f8f8;
    padding: 0.5rem 1rem;
    border-radius: 25px;
    border: 2px solid #ffe066;
}

/* Catalog Viewer */
.catalog-viewer {
    flex: 1;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 2rem;
    position: relative;
}

.book-container {
    width: 100%;
    max-width: 1200px;
    height: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
    perspective: 1500px;
}

.book {
    width: 1000px;
    height: 700px;
    position: relative;
    transform-style: preserve-3d;
    transform: rotateY(0deg);
    transition: transform 0.8s cubic-bezier(0.645, 0.045, 0.355, 1);
    margin: 0 auto;
    perspective: 2000px;
}

.book::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(90deg, 
        rgba(0,0,0,0.1) 0%, 
        rgba(0,0,0,0.05) 20%, 
        rgba(0,0,0,0) 50%, 
        rgba(0,0,0,0.05) 80%, 
        rgba(0,0,0,0.1) 100%);
    border-radius: 5px;
    pointer-events: none;
    z-index: 25;
}

.pdf-page {
    position: absolute;
    width: 500px;
    height: 700px;
    background: white;
    border-radius: 5px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
    overflow: hidden;
    cursor: pointer;
    display: none;
}

.pdf-page.left-page {
    left: 0;
}

.pdf-page.right-page {
    left: 500px;
}

.pdf-page:only-child {
    left: 250px;
}

.pdf-page canvas {
    width: 100%;
    height: 100%;
    object-fit: contain;
}

.pdf-page.active {
    display: block;
}

.pdf-page:nth-child(1) { }  /* Kapak */
.pdf-page:nth-child(2) { }
.pdf-page:nth-child(3) { }
.pdf-page:nth-child(4) { }
.pdf-page:nth-child(5) { }
.pdf-page:nth-child(6) { }
.pdf-page:nth-child(7) { }
.pdf-page:nth-child(8) { }
.pdf-page:nth-child(9) { }
.pdf-page:nth-child(10) { }
.pdf-page:nth-child(11) { }
.pdf-page:nth-child(12) { }
.pdf-page:nth-child(13) { }
.pdf-page:nth-child(14) { }
.pdf-page:nth-child(1) { z-index: 24; }  /* Kapak */
.pdf-page:nth-child(2) { z-index: 23; }
.pdf-page:nth-child(3) { z-index: 22; }
.pdf-page:nth-child(4) { z-index: 21; }
.pdf-page:nth-child(5) { z-index: 20; }
.pdf-page:nth-child(6) { z-index: 19; }
.pdf-page:nth-child(7) { z-index: 18; }
.pdf-page:nth-child(8) { z-index: 17; }
.pdf-page:nth-child(9) { z-index: 16; }
.pdf-page:nth-child(10) { z-index: 15; }
.pdf-page:nth-child(11) { z-index: 14; }
.pdf-page:nth-child(12) { z-index: 13; }
.pdf-page:nth-child(13) { z-index: 12; }
.pdf-page:nth-child(14) { z-index: 11; }
.pdf-page:nth-child(15) { z-index: 10; }
.pdf-page:nth-child(16) { z-index: 9; }
.pdf-page:nth-child(17) { z-index: 8; }
.pdf-page:nth-child(18) { z-index: 7; }
.pdf-page:nth-child(19) { z-index: 6; }
.pdf-page:nth-child(20) { z-index: 5; }
.pdf-page:nth-child(21) { z-index: 4; }
.pdf-page:nth-child(22) { z-index: 3; }
.pdf-page:nth-child(23) { z-index: 2; }
.pdf-page:nth-child(24) { z-index: 1; }  /* Arka kapak */

.page-content {
    width: 100%;
    height: 100%;
    padding: 2rem;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    background: white;
    transform: rotateY(0deg);
    backface-visibility: hidden;
}

/* Cover Page */
.cover-page {
    background: linear-gradient(135deg, #ffe066, #ffd700);
    transform-origin: left center;
}

.cover-page.flipped {
    transform: rotateY(-180deg);
}

.cover-page .page-content {
    transform: rotateY(0deg);
}

.cover-design {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    height: 100%;
    color: #333;
}

.cover-logo img {
    width: 200px;
    margin-bottom: 2rem;
    filter: drop-shadow(0 4px 8px rgba(0, 0, 0, 0.2));
}

.cover-design h2 {
    font-size: 4rem;
    font-weight: 900;
    margin-bottom: 1rem;
    color: #333;
}

.cover-design h3 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
    color: #333;
    letter-spacing: 0.5rem;
}

.cover-design p {
    font-size: 1.2rem;
    margin-bottom: 2rem;
    color: #666;
}

.cover-subtitle span {
    font-size: 1.5rem;
    font-weight: 700;
    color: #333;
    background: rgba(255, 255, 255, 0.8);
    padding: 0.5rem 2rem;
    border-radius: 25px;
    border: 2px solid #333;
}

/* Back Cover */
.back-cover {
    background: linear-gradient(135deg, #333, #1a1a1a);
    color: white;
    transform-origin: right center;
}

.back-cover.flipped {
    transform: rotateY(180deg);
}

.back-cover .page-content {
    transform: rotateY(180deg);
}

.back-cover-design {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    height: 100%;
}

.back-logo img {
    width: 150px;
    margin-bottom: 2rem;
    filter: brightness(0) invert(1);
}

.back-cover-design h2 {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 1rem;
    text-align: center;
    line-height: 1.4;
}

.back-cover-design p {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 2rem;
    color: #ffe066;
}

.qr-code {
    margin-top: 2rem;
}

.qr-placeholder {
    width: 100px;
    height: 100px;
    background: rgba(255, 255, 255, 0.1);
    border: 2px dashed rgba(255, 255, 255, 0.3);
    border-radius: 10px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    color: rgba(255, 255, 255, 0.7);
}

.qr-placeholder span {
    font-size: 0.8rem;
    font-weight: 600;
}

.qr-placeholder small {
    font-size: 0.6rem;
    margin-top: 0.5rem;
}

/* Regular Pages */
.page h2 {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 1.5rem;
    color: #333;
}

.page p {
    font-size: 1.1rem;
    line-height: 1.6;
    margin-bottom: 1.5rem;
    color: #666;
}

.service-highlight {
    background: #f8f8f8;
    padding: 1.5rem;
    border-radius: 10px;
    border-left: 4px solid #ffe066;
}

.service-highlight h3 {
    font-size: 1.3rem;
    font-weight: 600;
    margin-bottom: 1rem;
    color: #333;
}

.service-highlight ul {
    list-style: none;
}

.service-highlight li {
    padding: 0.5rem 0;
    color: #666;
    position: relative;
    padding-left: 1.5rem;
}

.service-highlight li::before {
    content: "•";
    color: #ffe066;
    font-weight: bold;
    position: absolute;
    left: 0;
}

/* Service Detail */
.service-detail {
    display: flex;
    align-items: center;
    gap: 2rem;
    margin-top: 2rem;
}

.service-icon img {
    width: 80px;
    height: 80px;
    object-fit: contain;
}

.service-text h3 {
    font-size: 1.4rem;
    font-weight: 600;
    margin-bottom: 1rem;
    color: #333;
}

.service-text ul {
    list-style: none;
}

.service-text li {
    padding: 0.3rem 0;
    color: #666;
    position: relative;
    padding-left: 1.5rem;
}

.service-text li::before {
    content: "→";
    color: #ffe066;
    position: absolute;
    left: 0;
}

/* References Grid */
.references-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 2rem;
    margin-top: 2rem;
}

.reference-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1rem;
    padding: 1.5rem;
    background: #f8f8f8;
    border-radius: 10px;
    transition: transform 0.3s ease;
}

.reference-item:hover {
    transform: translateY(-5px);
}

.reference-item img {
    width: 80px;
    height: 80px;
    object-fit: contain;
}

.reference-item span {
    font-size: 0.9rem;
    font-weight: 600;
    color: #333;
    text-align: center;
}

/* Contact Info */
.contact-info {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
    margin-top: 2rem;
}

.contact-item {
    text-align: center;
    padding: 1.5rem;
    background: #f8f8f8;
    border-radius: 10px;
}

.contact-item h3 {
    font-size: 1.2rem;
    font-weight: 600;
    margin-bottom: 1rem;
    color: #333;
}

.contact-item p {
    font-size: 1rem;
    color: #666;
    line-height: 1.4;
}

/* Social Media */
.social-media {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
    margin-top: 2rem;
}

.social-item {
    text-align: center;
    padding: 1.5rem;
    background: #f8f8f8;
    border-radius: 10px;
}

.social-item h3 {
    font-size: 1.2rem;
    font-weight: 600;
    margin-bottom: 1rem;
    color: #333;
}

.social-item p {
    font-size: 1rem;
    color: #666;
}

/* Navigation Controls */
.navigation-controls {
    position: fixed;
    bottom: 2rem;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    gap: 1rem;
    z-index: 1000;
}

.nav-btn {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 1rem 2rem;
    background: rgba(255, 255, 255, 0.95);
    border: 2px solid #ffe066;
    border-radius: 50px;
    font-size: 1rem;
    font-weight: 600;
    color: #333;
    cursor: pointer;
    transition: all 0.3s ease;
    backdrop-filter: blur(10px);
}

.nav-btn:hover {
    background: #ffe066;
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(255, 224, 102, 0.3);
}

.nav-btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    transform: none;
}

/* Close Button */
.close-btn {
    position: fixed;
    top: 4rem;
    right: 2rem;
    width: 50px;
    height: 50px;
    background: rgba(255, 255, 255, 0.95);
    border: 2px solid #ffe066;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.3s ease;
    backdrop-filter: blur(10px);
    z-index: 1000;
}

.close-btn:hover {
    background: #ffe066;
    transform: scale(1.1);
}

.close-btn svg {
    color: #333;
}

/* Loading Overlay */
.loading-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, #1a1a1a, #2a2a2a);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 9999;
    transition: opacity 0.5s ease;
}

.loading-content {
    text-align: center;
    color: white;
}

.loading-spinner {
    width: 50px;
    height: 50px;
    border: 3px solid #ffe066;
    border-top: 3px solid transparent;
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 0 auto 1rem;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

/* Responsive Design */
@media (max-width: 1200px) {
    .book {
        width: 800px;
        height: 560px;
    }
    
    .pdf-page {
        width: 400px;
        height: 560px;
    }
    
    .pdf-page.right-page {
        left: 400px;
    }
    
    .pdf-page:only-child {
        left: 200px;
    }
}

@media (max-width: 768px) {
    .book {
        width: 600px;
        height: 420px;
    }
    
    .pdf-page {
        width: 300px;
        height: 420px;
    }
    
    .pdf-page.right-page {
        left: 300px;
    }
    
    .pdf-page:only-child {
        left: 150px;
    }
    
    .navigation-controls {
        bottom: 1rem;
    }
    
    .nav-btn {
        padding: 0.8rem 1.5rem;
        font-size: 0.9rem;
    }
    
    .close-btn {
        top: 1rem;
        right: 1rem;
        width: 40px;
        height: 40px;
    }
}

@media (max-width: 480px) {
    .book {
        width: 400px;
        height: 280px;
    }
    
    .pdf-page {
        width: 200px;
        height: 280px;
    }
    
    .pdf-page.right-page {
        left: 200px;
    }
    
    .pdf-page:only-child {
        left: 100px;
    }
    
    .navigation-controls {
        flex-direction: column;
        gap: 0.5rem;
    }
    
    .nav-btn {
        padding: 0.6rem 1rem;
        font-size: 0.8rem;
    }
}