/* ===== LIVRO HTML PAGE STYLES ===== */

.livro-html-page {
    background-color: #f8f9fa;
}

.livro-layout {
    display: grid;
    grid-template-columns: 1fr 300px;
    gap: 30px;
    margin-top: 20px;
}

.livro-section {
    background: white;
    border-radius: 8px;
    overflow: hidden;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
}

.livro-info-header {
    padding: 30px;
    border-bottom: 1px solid #e0e0e0;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
}

.livro-title {
    font-size: 2.5rem;
    margin-bottom: 20px;
    color: white;
    text-shadow: 0 2px 4px rgba(0,0,0,0.3);
    line-height: 1.2;
}

.livro-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 15px;
}

.livro-stats {
    display: flex;
    gap: 20px;
    color: rgba(255,255,255,0.9);
    font-size: 0.95rem;
}

.livro-stats span {
    display: flex;
    align-items: center;
    gap: 5px;
}

.livro-actions {
    display: flex;
    gap: 10px;
}

.livro-access-info {
    margin-top: 0;
    margin-bottom: 0;
    padding-top: 12px;
    border-top: 1px solid rgba(255,255,255,0.2);
    width: 100%;
}

.access-days-remaining {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    color: #10b981;
    font-size: 0.95rem;
    font-weight: 500;
    padding: 8px 12px;
    background: rgba(16, 185, 129, 0.15);
    border-radius: 8px;
    border: 1px solid rgba(16, 185, 129, 0.3);
    backdrop-filter: blur(10px);
}

.access-days-remaining strong {
    color: #059669;
    font-weight: 700;
}

.action-btn {
    padding: 10px 20px;
    border: 2px solid rgba(255,255,255,0.3);
    background: rgba(255,255,255,0.1);
    color: white;
    border-radius: 25px;
    cursor: pointer;
    transition: all 0.3s ease;
    font-size: 0.9rem;
    backdrop-filter: blur(10px);
}

.action-btn:hover {
    background: rgba(255,255,255,0.2);
    border-color: rgba(255,255,255,0.5);
    transform: translateY(-2px);
}

/* Botão Favoritar */
.favorite-btn {
    transition: all 0.3s ease;
}

.favorite-btn.favorited {
    background: #ffc107 !important;
    color: #000 !important;
    border-color: #ffc107 !important;
}

.favorite-btn.favorited:hover {
    background: #e0a800 !important;
}

/* ===== SUMÁRIO (TOC) MODAL - DESIGN MODERNO PADRONIZADO ===== */

.livro-toc-modal {
    position: fixed;
    inset: 0;
    display: none;
    align-items: center;
    justify-content: center;
    z-index: 10000;
    backdrop-filter: blur(5px);
}

.livro-toc-backdrop {
    position: absolute;
    inset: 0;
    background: rgba(0,0,0,0.6);
}

.livro-toc-content {
    position: relative;
    background: #fff;
    width: min(900px, 92vw);
    max-height: 85vh;
    border-radius: 15px;
    overflow: hidden;
    box-shadow: 0 20px 50px rgba(0,0,0,0.3);
    animation: fadeInUp 0.4s ease-out;
}

.livro-toc-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 20px 25px;
    border-bottom: 1px solid #e9ecef;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: #fff;
}

.livro-toc-header h3 {
    margin: 0;
    font-size: 1.4rem;
    font-weight: 600;
}

.livro-toc-close {
    border: none;
    background: rgba(255,255,255,0.2);
    color: #fff;
    font-size: 24px;
    cursor: pointer;
    width: 40px;
    height: 40px;
    border-radius: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.3s ease;
}

.livro-toc-close:hover {
    background: rgba(255,255,255,0.3);
    transform: scale(1.1);
}

.livro-toc-body {
    padding: 25px;
    overflow: auto;
    max-height: 65vh;
}

.livro-toc-list {
    list-style: none;
    padding: 0;
    margin: 0;
}

.livro-toc-list li {
    margin: 8px 0;
    transition: all 0.2s ease;
}

.livro-toc-list li:hover {
    background-color: #f8f9fa;
    border-radius: 4px;
}

.livro-toc-link {
    display: flex;
    align-items: center;
    gap: 12px;
    color: #333;
    text-decoration: none !important;
    padding: 12px 15px;
    border-radius: 8px;
    transition: all 0.3s ease;
    border: 1px solid transparent;
    position: relative;
    font-size: 14px;
}

.livro-toc-link:hover {
    background: linear-gradient(135deg, #e3f2fd 0%, #f3e5f5 100%);
    color: #007bff;
    text-decoration: none !important;
    border-color: #007bff;
    transform: translateX(8px);
    box-shadow: 0 4px 12px rgba(0, 123, 255, 0.15);
}

/* Efeito de linha animada */
.livro-toc-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 3px;
    background: linear-gradient(90deg, #007bff, #667eea);
    transition: width 0.4s ease;
    border-radius: 2px;
}

.livro-toc-link:hover::after {
    width: 100%;
}

/* Níveis hierárquicos com indentação melhorada */
.toc-level-1 { 
    font-weight: 700; 
    font-size: 15px;
}

.toc-level-2 { 
    margin-left: 20px; 
    font-weight: 600;
}

.toc-level-3 { 
    margin-left: 40px; 
    font-weight: 500;
}

.toc-level-4 { 
    margin-left: 60px; 
    font-weight: 400;
}

.toc-level-5 { 
    margin-left: 80px; 
    font-weight: 400;
    opacity: 0.9;
}

.toc-level-6 { 
    margin-left: 100px; 
    font-weight: 400;
    opacity: 0.8;
}

.toc-page {
    color: #6c757d;
    font-size: 0.85em;
    background: #f8f9fa;
    padding: 2px 8px;
    border-radius: 12px;
    margin-left: auto;
    font-weight: 500;
}

/* Estado vazio */
.livro-toc-empty {
    text-align: center;
    padding: 40px 20px;
    color: #6c757d;
    background: #f8f9fa;
    border-radius: 8px;
    border: 2px dashed #dee2e6;
    font-size: 14px;
}

/* Animação para o modal */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px) scale(0.95);
    }
    to {
        opacity: 1;
        transform: translateY(0) scale(1);
    }
}

/* Conteúdo do Livro */
.livro-content {
    padding: 0;
}

.livro-pagination-nav {
    padding: 20px 30px;
    background: #f8f9fa;
    border-bottom: 1px solid #e0e0e0;
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 15px;
}

.pagination-controls .toc-btn {
    background: transparent;
}

.livro-pagination-nav.bottom {
    border-top: 1px solid #e0e0e0;
    border-bottom: none;
}

.pagination-info {
    font-weight: 600;
    color: #333;
    font-size: 1.1rem;
}

.pagination-controls {
    display: flex;
    gap: 15px;
}

.pagination-btn {
    padding: 10px 20px;
    border: 1px solid #ddd;
    background: white;
    color: #333;
    text-decoration: none;
    border-radius: 20px;
    transition: all 0.3s ease;
    font-weight: 500;
}

.pagination-btn:hover {
    background: #667eea;
    color: white;
    border-color: #667eea;
    transform: translateY(-1px);
}

.prev-btn {
    border-color: #667eea;
    color: #667eea;
}

.prev-btn:hover {
    background: #667eea;
    color: white;
}

.next-btn {
    background: #667eea;
    color: white;
    border-color: #667eea;
}

.next-btn:hover {
    background: #5a6fd8;
    border-color: #5a6fd8;
}

/* Conteúdo da Página */
.livro-page-content {
    padding: 40px;
}

.livro-page {
    max-width: 800px;
    margin: 0 auto;
    line-height: 1.8;
    font-size: 1.1rem;
    color: #333;
}

.livro-page h1, .livro-page h2, .livro-page h3, .livro-page h4, .livro-page h5, .livro-page h6 {
    color: #2c3e50;
    margin-top: 2em;
    margin-bottom: 1em;
    line-height: 1.3;
}

.livro-page h1 { font-size: 2rem; }
.livro-page h2 { font-size: 1.8rem; }
.livro-page h3 { font-size: 1.5rem; }
.livro-page h4 { font-size: 1.3rem; }

.livro-page p {
    margin-bottom: 1.2em;
    text-align: justify;
}

.livro-page ul, .livro-page ol {
    margin-bottom: 1.2em;
    padding-left: 2em;
}

.livro-page li {
    margin-bottom: 0.5em;
}

.livro-page blockquote {
    border-left: 4px solid #667eea;
    padding-left: 20px;
    margin: 1.5em 0;
    font-style: italic;
    color: #666;
    background: #f8f9fa;
    padding: 20px;
    border-radius: 0 8px 8px 0;
}

.livro-page table {
    width: 100%;
    border-collapse: collapse;
    margin: 1.5em 0;
    border-radius: 8px;
    overflow: hidden;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
}

.livro-page th, .livro-page td {
    padding: 12px 15px;
    text-align: left;
    border-bottom: 1px solid #e0e0e0;
}

.livro-page th {
    background: #667eea;
    color: white;
    font-weight: 600;
}

.livro-page tr:nth-child(even) {
    background: #f8f9fa;
}

.livro-page tr:hover {
    background: #e3f2fd;
}

.livro-page img {
    max-width: 100%;
    height: auto;
    border-radius: 8px;
    margin: 1em 0;
    box-shadow: 0 4px 12px rgba(0,0,0,0.15);
}

.livro-page code {
    background: #f1f3f4;
    padding: 2px 6px;
    border-radius: 4px;
    font-family: 'Courier New', monospace;
    font-size: 0.9em;
}

.livro-page pre {
    background: #2d3748;
    color: #e2e8f0;
    padding: 20px;
    border-radius: 8px;
    overflow-x: auto;
    margin: 1.5em 0;
}

.livro-page pre code {
    background: none;
    padding: 0;
    color: inherit;
}

/* Descrição do Livro */
.livro-description {
    padding: 30px;
    border-top: 1px solid #e0e0e0;
}

.livro-description h3 {
    font-size: 1.8rem;
    margin-bottom: 20px;
    color: #333;
    border-bottom: 2px solid #667eea;
    padding-bottom: 10px;
}

.livro-description p {
    font-size: 1.1rem;
    line-height: 1.7;
    color: #555;
    margin-bottom: 20px;
}

.livro-tags {
    margin-top: 25px;
}

.livro-tags h4 {
    font-size: 1.3rem;
    margin-bottom: 15px;
    color: #333;
}

.tags-container {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
}

.tag {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 8px 16px;
    border-radius: 20px;
    font-size: 0.9rem;
    font-weight: 500;
    transition: all 0.3s ease;
}

.tag:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(102, 126, 234, 0.4);
}

/* Sidebar */
.livro-sidebar {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.related-livros, .reading-instructions, .sidebar-ads {
    background: white;
    padding: 25px;
    border-radius: 8px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
}

.related-livros h3, .reading-instructions h3 {
    font-size: 1.4rem;
    margin-bottom: 20px;
    color: #333;
    border-bottom: 2px solid #667eea;
    padding-bottom: 10px;
}

/* Channel Info (melhoria visual) */
.channel-info {
    background: white;
    padding: 25px;
    border-radius: 8px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.08);
}

.channel-info h3 {
    font-size: 1.4rem;
    margin-bottom: 16px;
    color: #333;
    border-bottom: 2px solid #667eea;
    padding-bottom: 8px;
}

.channel-card {
    display: grid;
    grid-template-columns: 60px 1fr auto;
    gap: 16px;
    align-items: center;
    background: linear-gradient(135deg, #f8f9ff, #f4f2ff);
    padding: 16px;
    border: 1px solid #ececff;
    border-radius: 10px;
}

.channel-avatar {
    width: 60px;
    height: 60px;
    border-radius: 50%;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    color: #fff;
    font-size: 26px;
    box-shadow: 0 6px 16px rgba(118,75,162,0.25);
}

.channel-details {
    overflow: hidden;
}

.channel-name a {
    color: #2c3e50;
    text-decoration: none;
}

.channel-name a:hover {
    color: #5a6fd8;
}

.channel-description {
    color: #555;
    margin: 6px 0 0 0;
    font-size: 0.95rem;
}

.visit-channel-btn {
    text-decoration: none;
    padding: 10px 16px;
    background: #667eea;
    color: #fff;
    border-radius: 24px;
    font-weight: 600;
    transition: background 0.2s ease;
}

.visit-channel-btn:hover {
    background: #5a6fd8;
}

.related-livro-item {
    display: flex;
    gap: 15px;
    margin-bottom: 20px;
    padding-bottom: 20px;
    border-bottom: 1px solid #f0f0f0;
}

.related-livro-item:last-child {
    border-bottom: none;
    margin-bottom: 0;
    padding-bottom: 0;
}

.related-livro-thumb {
    position: relative;
    width: 80px;
    height: 100px;
    border-radius: 6px;
    overflow: hidden;
    background: #f0f0f0;
    flex-shrink: 0;
}

.related-livro-thumb img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.thumb-placeholder {
    width: 100%;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2rem;
    color: #999;
}

.livro-overlay {
    position: absolute;
    bottom: 4px;
    right: 4px;
    background: rgba(102, 126, 234, 0.9);
    color: white;
    padding: 2px 8px;
    border-radius: 4px;
    font-size: 0.7rem;
    font-weight: 600;
}

.related-livro-info h4 {
    margin: 0 0 8px 0;
    font-size: 1rem;
    line-height: 1.3;
    color: #333;
}

.related-livro-meta {
    font-size: 0.85rem;
    color: #666;
    display: flex;
    gap: 15px;
}

.related-livro-link {
    text-decoration: none;
    color: inherit;
    transition: all 0.3s ease;
}

.related-livro-link:hover {
    transform: translateX(5px);
}

.related-livro-link:hover h4 {
    color: #667eea;
}

.reading-instructions ul {
    list-style: none;
    padding: 0;
}

.reading-instructions li {
    margin-bottom: 12px;
    font-size: 0.95rem;
    color: #555;
    padding-left: 20px;
    position: relative;
}

.reading-instructions li:before {
    content: "•";
    color: #667eea;
    font-weight: bold;
    position: absolute;
    left: 0;
}

.sidebar-ads {
    text-align: center;
}

.ad-placeholder {
    height: 250px;
    background: linear-gradient(135deg, #f8f9fa 0%, #e9ecef 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    color: #999;
    border-radius: 6px;
    border: 2px dashed #ddd;
}

.no-related-content {
    text-align: center;
    padding: 30px 20px;
    color: #666;
    background: #f8f9fa;
    border-radius: 8px;
    margin: 10px 0;
}

.no-related-content p {
    margin-bottom: 15px;
    font-size: 0.95rem;
}

.btn-explore-channel {
    display: inline-block;
    padding: 10px 20px;
    background: #667eea;
    color: white;
    text-decoration: none;
    border-radius: 25px;
    font-size: 0.9rem;
    transition: background-color 0.3s ease;
}

.btn-explore-channel:hover {
    background: #5a6fd8;
    color: white;
}

/* Seção de Comentários */
.comments-section {
    background: white;
    padding: 30px;
    border-top: 1px solid #e0e0e0;
}

.comments-title {
    font-size: 1.8rem;
    margin-bottom: 25px;
    color: #333;
    border-bottom: 2px solid #667eea;
    padding-bottom: 15px;
}

.comment-form-container h4 {
    font-size: 1.3rem;
    margin-bottom: 20px;
    color: #555;
}

.comment-form {
    display: flex;
    flex-direction: column;
    gap: 20px;
    margin-bottom: 30px;
}

.form-group {
    display: flex;
    flex-direction: column;
}

.form-group label {
    font-size: 0.95rem;
    color: #666;
    margin-bottom: 8px;
    font-weight: 500;
}

.form-control {
    padding: 15px;
    border: 2px solid #e0e0e0;
    border-radius: 8px;
    font-size: 1rem;
    resize: vertical;
    min-height: 120px;
    transition: border-color 0.3s ease;
}

.form-control:focus {
    outline: none;
    border-color: #667eea;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

.btn-submit-comment {
    padding: 15px 30px;
    background: #667eea;
    color: white;
    border: none;
    border-radius: 25px;
    cursor: pointer;
    font-size: 1rem;
    font-weight: 600;
    transition: all 0.3s ease;
    align-self: flex-start;
}

.btn-submit-comment:hover {
    background: #5a6fd8;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(102, 126, 234, 0.4);
}

.comment-login-required {
    font-size: 1.1rem;
    color: #666;
    padding: 20px;
    background: #f8f9fa;
    border-radius: 8px;
    text-align: center;
    margin: 20px 0;
    border: 2px dashed #ddd;
}

.comments-list {
    margin-top: 30px;
}

.no-comments {
    text-align: center;
    padding: 40px 20px;
    color: #666;
    font-style: italic;
    background: #f8f9fa;
    border-radius: 8px;
}

.comment-item {
    display: flex;
    gap: 20px;
    margin-bottom: 25px;
    padding-bottom: 25px;
    border-bottom: 1px solid #f0f0f0;
}

.comment-item:last-child {
    border-bottom: none;
    margin-bottom: 0;
    padding-bottom: 0;
}

.comment-avatar {
    width: 50px;
    height: 50px;
    border-radius: 50%;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    flex-shrink: 0;
}

.comment-details {
    flex: 1;
}

.comment-author {
    font-weight: 600;
    color: #333;
    font-size: 1rem;
    margin-bottom: 5px;
}

.comment-date {
    font-size: 0.85rem;
    color: #999;
    margin-bottom: 10px;
}

.comment-text {
    font-size: 1rem;
    line-height: 1.6;
    color: #444;
}

/* Responsividade */
@media (max-width: 768px) {
    .livro-layout {
        grid-template-columns: 1fr;
        gap: 20px;
    }
    
    .livro-title {
        font-size: 2rem;
    }
    
    .livro-meta {
        flex-direction: column;
        align-items: flex-start;
        gap: 20px;
    }
    
    .livro-stats {
        flex-wrap: wrap;
        gap: 15px;
    }

    .livro-access-info {
        width: 100%;
        text-align: center;
    }

    .access-days-remaining {
        font-size: 0.9rem;
        padding: 6px 10px;
    }
    
    .livro-pagination-nav {
        flex-direction: column;
        text-align: center;
        gap: 20px;
    }
    
    .pagination-controls {
        justify-content: center;
    }
    
    .livro-page-content {
        padding: 20px;
    }
    
    .livro-page {
        font-size: 1rem;
    }
    
    .livro-page h1 { font-size: 1.8rem; }
    .livro-page h2 { font-size: 1.6rem; }
    .livro-page h3 { font-size: 1.4rem; }
    
    .livro-info-header {
        padding: 20px;
    }
    
    .livro-description, .comments-section {
        padding: 20px;
    }
    
    .related-livro-item {
        flex-direction: column;
        text-align: center;
    }
    
    .related-livro-thumb {
        width: 100%;
        height: 120px;
        margin-bottom: 15px;
    }

    .livro-toc-content {
        width: 94vw;
        max-height: 85vh;
    }

    /* Evitar vazamento horizontal de tabelas no mobile */
    .livro-page table {
        display: block;
        max-width: 100%;
        overflow-x: auto;
        -webkit-overflow-scrolling: touch;
    }
    .livro-page th,
    .livro-page td {
        word-break: break-word;
        overflow-wrap: anywhere;
    }
}

/* Animações */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.livro-page {
    animation: fadeInUp 0.6s ease-out;
}

.pagination-btn {
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.pagination-btn:hover {
    transform: translateY(-2px) scale(1.05);
}

/* Estados de carregamento */
.livro-page.loading {
    opacity: 0.6;
    pointer-events: none;
}

/* Melhorias de acessibilidade */
.pagination-btn:focus,
.action-btn:focus,
.btn-submit-comment:focus {
    outline: 2px solid #667eea;
    outline-offset: 2px;
}

/* ========== VÍDEO RELACIONADO ========== */
.related-video-section {
    background: linear-gradient(135deg, #f8f9fa 0%, #ffffff 100%);
    border-radius: 16px;
    padding: 24px;
    margin-bottom: 20px;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
    border: 1px solid #e9ecef;
}

.related-video-section h3 {
    color: #333;
    font-size: 1.3rem;
    font-weight: 700;
    margin-bottom: 20px;
    padding-bottom: 12px;
    border-bottom: 2px solid #e9ecef;
}

.video-container {
    display: flex;
    gap: 20px;
    align-items: flex-start;
}

.video-thumbnail {
    flex-shrink: 0;
    width: 180px;
    height: 100px;
    border-radius: 12px;
    overflow: hidden;
    background: linear-gradient(135deg, #e9ecef 0%, #dee2e6 100%);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
    position: relative;
}

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

.video-placeholder {
    width: 100%;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2.5rem;
    color: #adb5bd;
}

.play-button {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    font-size: 2rem;
    background: rgba(0, 0, 0, 0.6);
    width: 50px;
    height: 50px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.3s ease;
}

.video-thumbnail:hover .play-button {
    background: rgba(102, 126, 234, 0.9);
    transform: translate(-50%, -50%) scale(1.1);
}

.video-info {
    flex: 1;
    min-width: 0;
}

.video-info h4 {
    color: #333;
    font-size: 1.15rem;
    font-weight: 600;
    margin-bottom: 10px;
    line-height: 1.4;
}

.video-description {
    color: #6c757d;
    font-size: 0.95rem;
    line-height: 1.6;
    margin-bottom: 12px;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.video-meta {
    display: flex;
    gap: 16px;
    margin-bottom: 16px;
    flex-wrap: wrap;
}

.video-meta span {
    color: #6c757d;
    font-size: 0.85rem;
    display: flex;
    align-items: center;
    gap: 4px;
}

.watch-video-btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background: linear-gradient(135deg, #ff6b6b 0%, #ee5a5a 100%);
    color: white;
    padding: 10px 20px;
    border-radius: 8px;
    font-weight: 600;
    font-size: 0.9rem;
    text-decoration: none;
    transition: all 0.3s ease;
    box-shadow: 0 4px 12px rgba(255, 107, 107, 0.3);
}

.watch-video-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 16px rgba(255, 107, 107, 0.4);
    color: white;
}

/* Mobile - Vídeo Relacionado */
@media (max-width: 768px) {
    .related-video-section {
        padding: 20px;
        margin-bottom: 16px;
        border-radius: 12px;
    }

    .related-video-section h3 {
        font-size: 1.15rem;
        margin-bottom: 16px;
    }

    .video-container {
        flex-direction: column;
        align-items: center;
        text-align: center;
    }

    .video-thumbnail {
        width: 100%;
        max-width: 280px;
        height: 157px;
    }

    .video-info h4 {
        font-size: 1.05rem;
    }

    .video-description {
        font-size: 0.9rem;
    }

    .video-meta {
        justify-content: center;
    }

    .watch-video-btn {
        width: 100%;
        justify-content: center;
    }
}

/* Modo escuro (opcional) */
@media (prefers-color-scheme: dark) {
    .livro-html-page {
        background-color: #1a1a1a;
    }

    .livro-section, .related-livros, .reading-instructions, .sidebar-ads {
        background: #2d2d2d;
        color: #e0e0e0;
    }

    .livro-page {
        color: #e0e0e0;
    }

    .livro-page h1, .livro-page h2, .livro-page h3, .livro-page h4, .livro-page h5, .livro-page h6 {
        color: #ffffff;
    }

    .related-video-section {
        background: linear-gradient(135deg, #2d2d2d 0%, #3d3d3d 100%);
        border-color: #404040;
    }

    .related-video-section h3 {
        color: #e0e0e0;
        border-color: #404040;
    }

    .video-info h4 {
        color: #e0e0e0;
    }

    .video-description,
    .video-meta span {
        color: #a0a0a0;
    }
}