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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
    background-color: #fafafa;
    color: #262626;
    line-height: 1.4;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

.header {
    background: #fff;
    border-bottom: 1px solid #dbdbdb;
    top: 0;
    z-index: 100;
}

.header-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 60px;
    padding: 0 20px;
    max-width: 1200px;
    margin: 0 auto;
}

.logo a {
    display: flex;
    align-items: center;
    gap: 8px;
    text-decoration: none;
    font-size: 20px;
    font-weight: 700;
    color: #262626;
    transition: color 0.2s ease;
}

.logo a:hover {
    color: #0095f6;
}

.logo i {
    font-size: 22px;
    color: #0095f6;
}

.search-box {
    flex: 1;
    max-width: 400px;
    margin: 0 20px;
}

.search-form {
    display: flex;
    align-items: center;
    gap: 8px;
}

.search-input-wrapper {
    position: relative;
    flex: 1;
}

.search-icon {
    position: absolute;
    left: 12px;
    top: 50%;
    transform: translateY(-50%);
    color: #8e8e8e;
    font-size: 14px;
    pointer-events: none;
}

.search-input {
    width: 100%;
    height: 36px;
    padding: 0 16px 0 36px;
    background: #efefef;
    border: 1px solid #dbdbdb;
    border-radius: 20px;
    font-size: 14px;
    outline: none;
    transition: all 0.2s ease;
}

.search-input:focus {
    background: #fff;
    border-color: #0095f6;
    box-shadow: 0 0 0 2px rgba(0, 149, 246, 0.1);
}

.search-input:focus + .search-icon {
    color: #0095f6;
}

.search-btn {
    width: 36px;
    height: 36px;
    background: #0095f6;
    border: none;
    border-radius: 50%;
    color: white;
    font-size: 14px;
    cursor: pointer;
    transition: all 0.2s ease;
    display: flex;
    align-items: center;
    justify-content: center;
}

.search-btn:hover {
    background: #1877f2;
    transform: scale(1.05);
}

.header-actions {
    display: flex;
    align-items: center;
    gap: 12px;
}

/* Dil Seçici Stilleri */
.language-selector {
    position: relative;
}

.language-toggle {
    display: flex;
    align-items: center;
    gap: 6px;
    padding: 6px 12px;
    background: #efefef;
    border: none;
    border-radius: 20px;
    color: #262626;
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s ease;
    min-width: 70px;
    justify-content: center;
}

.language-toggle:hover {
    background: #e0e0e0;
    transform: translateY(-1px);
}

.language-toggle.active {
    background: #0095f6;
    color: white;
}

.language-flag {
    font-size: 16px;
    line-height: 1;
}

.language-code {
    font-size: 12px;
    font-weight: 600;
    letter-spacing: 0.5px;
}

.language-toggle i {
    font-size: 10px;
    transition: transform 0.2s ease;
}

.language-toggle.active i {
    transform: rotate(180deg);
}

.language-dropdown {
    position: absolute;
    top: calc(100% + 8px);
    right: 0;
    background: white;
    border: 1px solid #dbdbdb;
    border-radius: 12px;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.15);
    min-width: 200px;
    z-index: 1000;
    opacity: 0;
    visibility: hidden;
    transform: translateY(-10px);
    transition: all 0.3s ease;
}

.language-dropdown.active {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.language-dropdown-header {
    padding: 12px 16px;
    border-bottom: 1px solid #efefef;
    font-size: 12px;
    font-weight: 600;
    color: #8e8e8e;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.language-option {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px 16px;
    color: #262626;
    text-decoration: none;
    font-size: 14px;
    transition: all 0.2s ease;
    border-bottom: 1px solid #f8f9fa;
}

.language-option:last-child {
    border-bottom: none;
    border-radius: 0 0 12px 12px;
}

.language-option:hover {
    background: #f8f9fa;
    color: #0095f6;
}

.language-option.active {
    background: #e3f2fd;
    color: #0095f6;
    font-weight: 500;
}

.language-option .language-flag {
    font-size: 18px;
}

.language-option .language-name {
    flex: 1;
    font-weight: 500;
}

.language-option i.fas.fa-check {
    color: #0095f6;
    font-size: 12px;
}

/* Bayrak Stilleri */
.language-flag {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 20px;
    height: 14px;
    border-radius: 2px;
    box-shadow: 0 1px 2px rgba(0,0,0,0.2);
    font-size: 0; /* Metni gizle */
    overflow: hidden;
}

/* SVG Bayrak Şəkilləri */
.language-flag-img {
    width: 20px;
    height: 14px;
    border-radius: 2px;
    box-shadow: 0 1px 3px rgba(0,0,0,0.2);
    object-fit: cover;
    display: inline-block;
}

.flag-az {
    background: linear-gradient(to bottom, #0099cc 33%, #ff0000 33%, #ff0000 66%, #00cc00 66%);
}

.flag-tr {
    background: #e30a17;
    position: relative;
}

.flag-tr::before {
    content: '★';
    position: absolute;
    color: white;
    font-size: 8px;
    left: 50%;
    top: 50%;
    transform: translate(-50%, -50%);
}

.flag-ru {
    background: linear-gradient(to bottom, white 33%, #0052cc 33%, #0052cc 66%, #cc0000 66%);
}

.flag-de {
    background: linear-gradient(to bottom, #000000 33%, #ff0000 33%, #ff0000 66%, #ffcc00 66%);
}

.flag-en {
    background: #012169;
    position: relative;
}

.flag-en::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background:
        linear-gradient(45deg, transparent 40%, white 40%, white 60%, transparent 60%),
        linear-gradient(-45deg, transparent 40%, white 40%, white 60%, transparent 60%),
        linear-gradient(90deg, transparent 45%, white 45%, white 55%, transparent 55%),
        linear-gradient(0deg, transparent 45%, white 45%, white 55%, transparent 55%);
}

.flag-en::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background:
        linear-gradient(45deg, transparent 42%, #c8102e 42%, #c8102e 58%, transparent 58%),
        linear-gradient(-45deg, transparent 42%, #c8102e 42%, #c8102e 58%, transparent 58%),
        linear-gradient(90deg, transparent 47%, #c8102e 47%, #c8102e 53%, transparent 53%),
        linear-gradient(0deg, transparent 47%, #c8102e 47%, #c8102e 53%, transparent 53%);
}

/* Mobil uyumluluk */
@media (max-width: 768px) {
    .language-flag {
        width: 18px;
        height: 12px;
        font-size: 0; /* Metni gizle */
    }
    
    .language-flag-img {
        width: 18px;
        height: 12px;
    }
    
    .flag-tr::before {
        font-size: 7px;
    }
}

.nav-link {
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: #efefef;
    border-radius: 50%;
    color: #8e8e8e;
    text-decoration: none;
    font-size: 16px;
    transition: all 0.2s ease;
}

.nav-link:hover {
    background: #0095f6;
    color: white;
    transform: scale(1.05);
}

.search-toggle {
    border: none;
    cursor: pointer;
}

.search-toggle:hover {
    background: #0095f6;
    color: white;
    transform: scale(1.05);
}

.main {
    min-height: calc(100vh - 60px);
    padding: 20px 0;
}

.main-layout {
    display: grid;
    grid-template-columns: 280px 1fr;
    gap: 24px;
    align-items: start;
}

.sidebar {
    background: #fff;
    border-radius: 12px;
    box-shadow: 0 2px 12px rgba(0,0,0,0.08);
    overflow: hidden;
}

.sidebar-content {
    padding: 0;
}

.sidebar-title {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 20px 20px 16px;
    margin: 0;
    font-size: 16px;
    font-weight: 600;
    color: #262626;
}

.sidebar-title i {
    color: #0095f6;
}

.category-nav {
    padding: 8px 0;
}

.category-link {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px 20px;
    color: #262626;
    text-decoration: none;
    font-size: 14px;
    font-weight: 500;
    transition: all 0.2s ease;
    border-left: 3px solid transparent;
}

.category-link:hover {
    background: #f8f9fa;
    color: #0095f6;
    border-left-color: #0095f6;
}

.category-link i {
    color: #8e8e8e;
    font-size: 14px;
    width: 16px;
    text-align: center;
}

.category-link:hover i {
    color: #0095f6;
}

.sidebar-footer {
    padding: 12px;
    background: #f8f9fa;
    border-top: 1px solid #e9ecef;
}


.content-area {
    min-height: 500px;
}

.page-header {
    text-align: center;
    margin-bottom: 30px;
}

.page-header h1 {
    font-size: 28px;
    font-weight: 300;
    color: #262626;
    margin-bottom: 8px;
}

.page-description {
    font-size: 16px;
    color: #8e8e8e;
    margin-top: 8px;
    line-height: 1.5;
}

.search-info {
    font-size: 15px;
    color: #8e8e8e;
    margin-top: 12px;
    padding: 12px 20px;
    background: #f8f9fa;
    border-radius: 8px;
    display: inline-block;
}

.search-info strong {
    color: #262626;
    font-weight: 600;
}

.breadcrumb {
    font-size: 12px;
    color: #8e8e8e;
    text-align: center;
}

.breadcrumb a {
    color: #0095f6;
    text-decoration: none;
}

.lessons-grid {
    display: flex;
    flex-direction: column;
    gap: 24px;
}

.lesson-card {
    background: #fff;
    border: 1px solid #dbdbdb;
    border-radius: 8px;
    overflow: hidden;
}
.lesson-card a {
    color: #000;
}

.lesson-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 14px 16px;
    border-bottom: 1px solid #efefef;
}

.lesson-category {
    font-size: 12px;
    font-weight: 600;
    color: #8e8e8e;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.lesson-date {
    font-size: 12px;
    color: #8e8e8e;
}

.lesson-content {
    padding: 16px;
}

.lesson-title {
    margin-bottom: 12px;
}

.lesson-title a {
    text-decoration: none;
    color: #262626;
    font-size: 16px;
    font-weight: 400;
    line-height: 1.4;
}

.lesson-content .lesson-content {
    font-size: 14px;
    color: #262626;
    line-height: 1.5;
    margin-bottom: 12px;
}

.lesson-footer {
    padding: 0 16px 16px;
    border-top: 1px solid #efefef;
    padding-top: 12px;
}

.read-more-btn {
    color: #0095f6;
    text-decoration: none;
    font-size: 14px;
    font-weight: 600;
    transition: color 0.2s;
}

.read-more-btn:hover {
    color: #00376b;
}

.lesson-page {
    max-width: 1200px;
    margin: 0 auto;
    background: #fff;
    border-radius: 12px;
    box-shadow: 0 2px 20px rgba(0,0,0,0.08);
    overflow: hidden;
}

.lesson-page.full-width {
    grid-column: 1 / -1;
}

.breadcrumb-nav {
    background: #f8f9fa;
    padding: 16px 40px;
    border-bottom: 1px solid #e9ecef;
}

.breadcrumb {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 14px;
}

.breadcrumb-item {
    display: flex;
    align-items: center;
    gap: 6px;
    color: #0095f6;
    text-decoration: none;
    padding: 4px 8px;
    border-radius: 6px;
    transition: all 0.2s ease;
}

.breadcrumb-item:hover {
    background: #e3f2fd;
    color: #1877f2;
}

.breadcrumb-separator {
    color: #8e8e8e;
    font-size: 12px;
}

.breadcrumb-current {
    display: flex;
    align-items: center;
    gap: 6px;
    color: #262626;
    font-weight: 500;
}

.lesson-page .lesson-header {
    padding: 32px;
    background: #fff;
    border-bottom: 1px solid #eee;
    max-width: 800px;
    margin: 0 auto;
}

.lesson-page .lesson-title {
    font-size: 26px;
    font-weight: 600;
    margin-bottom: 0;
    color: #1a1a1a;
    line-height: 1.4;
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', system-ui, sans-serif;
}

.lesson-body {
    padding: 32px;
    max-width: 800px;
    margin: 0 auto;
}

.content-wrapper {
    font-size: 17px;
    line-height: 1.7;
    color: #333;
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', system-ui, sans-serif;
}

.content-wrapper p {
    margin: 0 0 16px 0;
    line-height: 1.7;
}

.content-wrapper p:last-child {
    margin-bottom: 0;
}

.content-wrapper strong {
    color: #1a1a1a;
    font-weight: 600;
}

.content-wrapper em {
    font-style: italic;
    color: #555;
}

.lesson-point {
    margin: 8px 0;
    padding: 4px 0 4px 24px;
    position: relative;
    font-size: 16px;
    line-height: 1.6;
    color: #333;
}

.lesson-point::before {
    content: '•';
    position: absolute;
    left: 0;
    color: #007acc;
    font-size: 18px;
    font-weight: bold;
    top: 2px;
}

.lesson-actions {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 32px 40px;
    background: #f8f9fa;
    border-top: 1px solid #e9ecef;
}

.action-buttons {
    display: flex;
    gap: 12px;
}

.btn-share {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 10px 16px;
    background: #6c757d;
    color: white;
    border: none;
    border-radius: 6px;
    text-decoration: none;
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s ease;
}

.btn-share:hover {
    background: #5a6268;
    transform: translateY(-1px);
}

.lesson-stats {
    display: flex;
    gap: 20px;
}

.stat-item {
    display: flex;
    align-items: center;
    gap: 6px;
    color: #8e8e8e;
    font-size: 14px;
    cursor: pointer;
    transition: color 0.2s ease;
}

.stat-item:hover {
    color: #0095f6;
}

.btn-primary, .btn-secondary {
    display: inline-block;
    padding: 8px 16px;
    border-radius: 4px;
    text-decoration: none;
    font-size: 14px;
    font-weight: 600;
    transition: all 0.2s;
    border: none;
    cursor: pointer;
}

.btn-primary {
    background: #0095f6;
    color: white;
}

.btn-primary:hover {
    background: #1877f2;
    color: white;
}

.btn-secondary {
    background: #efefef;
    color: #262626;
    border: 1px solid #dbdbdb;
}

.btn-secondary:hover {
    background: #dbdbdb;
}

.pagination {
    display: flex;
    justify-content: center;
    gap: 8px;
    margin-top: 40px;
}

.page-link, .page-current {
    padding: 8px 12px;
    border-radius: 4px;
    text-decoration: none;
    font-size: 14px;
    font-weight: 600;
    transition: all 0.2s;
}

.page-link {
    color: #8e8e8e;
    background: #fff;
    border: 1px solid #dbdbdb;
}

.page-link:hover {
    background: #efefef;
    color: #262626;
}

.page-current {
    background: #0095f6;
    color: white;
}

.no-content {
    text-align: center;
    padding: 60px 20px;
    color: #8e8e8e;
}

.no-content h2 {
    font-size: 20px;
    font-weight: 300;
    color: #262626;
    margin-bottom: 8px;
}

.empty-state {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 80px 20px;
    text-align: center;
    background: white;
    border-radius: 16px;
    box-shadow: 0 2px 20px rgba(0, 0, 0, 0.05);
    margin: 40px 0;
    animation: fadeInUp 0.6s ease-out;
}

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

.empty-state-icon {
    margin-bottom: 24px;
    animation: float 3s ease-in-out infinite;
}

@keyframes float {
    0%, 100% {
        transform: translateY(0);
    }
    50% {
        transform: translateY(-10px);
    }
}

.empty-state-title {
    font-size: 24px;
    font-weight: 600;
    color: #262626;
    margin: 0 0 12px 0;
}

.empty-state-text {
    font-size: 16px;
    color: #8e8e8e;
    margin: 0 0 32px 0;
    line-height: 1.6;
    max-width: 500px;
}

.empty-state-actions {
    display: flex;
    gap: 12px;
    justify-content: center;
    flex-wrap: wrap;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 12px 24px;
    border-radius: 8px;
    font-size: 15px;
    font-weight: 600;
    text-decoration: none;
    transition: all 0.3s ease;
    border: none;
    cursor: pointer;
}

.btn-primary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.4);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(102, 126, 234, 0.5);
}

.btn-primary svg {
    width: 16px;
    height: 16px;
}

.btn-secondary {
    background: #f0f0f0;
    color: #262626;
    border: 2px solid #e0e0e0;
}

.btn-secondary:hover {
    background: #e5e5e5;
    border-color: #d0d0d0;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}

.btn-secondary svg {
    width: 16px;
    height: 16px;
}

.search-tips {
    width: 100%;
    max-width: 600px;
    margin: 0 0 32px 0;
}

.tips-title {
    font-size: 16px;
    font-weight: 600;
    color: #262626;
    margin: 0 0 16px 0;
    text-align: left;
}

.tips-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 16px;
}

.tip-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
    padding: 16px;
    background: #f8f9fa;
    border-radius: 12px;
    transition: all 0.3s ease;
}

.tip-item:hover {
    background: #e9ecef;
    transform: translateY(-3px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
}

.tip-icon {
    font-size: 32px;
    line-height: 1;
}

.tip-item p {
    margin: 0;
    font-size: 13px;
    color: #555;
    text-align: center;
    line-height: 1.4;
}

@media (max-width: 768px) {
    .empty-state {
        padding: 60px 20px;
    }
    
    .empty-state-icon svg {
        width: 100px;
        height: 100px;
    }
    
    .empty-state-title {
        font-size: 20px;
    }
    
    .empty-state-text {
        font-size: 14px;
    }
    
    .tips-grid {
        grid-template-columns: 1fr;
        gap: 12px;
    }
    
    .tip-item {
        padding: 12px;
    }
}

.error-page {
    text-align: center;
    padding: 80px 20px;
}

.error-content h1 {
    font-size: 64px;
    font-weight: 100;
    color: #262626;
    margin-bottom: 16px;
}

.error-content h2 {
    font-size: 24px;
    font-weight: 300;
    color: #262626;
    margin-bottom: 16px;
}

.error-actions {
    display: flex;
    gap: 12px;
    justify-content: center;
    margin-top: 24px;
}

.search-info {
    font-size: 14px;
    color: #8e8e8e;
    margin-bottom: 20px;
    text-align: center;
}

.search-suggestions {
    margin-top: 24px;
    text-align: center;
}

.search-suggestions ul {
    list-style: none;
    margin-top: 12px;
}

.search-suggestions li {
    padding: 8px 0;
    font-size: 14px;
    color: #8e8e8e;
}

.lessons-info {
    background: #fff;
    padding: 16px;
    border-radius: 8px;
    margin-bottom: 20px;
    border: 1px solid #dbdbdb;
    text-align: center;
    font-size: 14px;
    color: #8e8e8e;
}

.related-lessons {
    margin-top: 0;
    padding: 40px 40px;
    background: #f8f9fa;
    border-top: 1px solid #e9ecef;
}

.section-header {
    text-align: center;
    margin-bottom: 24px;
}

.section-header h2 {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    font-size: 20px;
    font-weight: 600;
    color: #262626;
    margin-bottom: 8px;
}

.section-header p {
    color: #8e8e8e;
    font-size: 14px;
}

.related-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 16px;
}

.related-lesson-card {
    background: #fff;
    border: 1px solid #e9ecef;
    border-radius: 12px;
    padding: 20px;
    transition: all 0.3s ease;
    box-shadow: 0 2px 8px rgba(0,0,0,0.04);
}

.related-lesson-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 16px rgba(0,0,0,0.1);
    border-color: #0095f6;
}

.related-lesson-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 12px;
}

.related-category {
    display: flex;
    align-items: center;
    gap: 6px;
    background: #e3f2fd;
    color: #0095f6;
    padding: 4px 8px;
    border-radius: 12px;
    font-size: 12px;
    font-weight: 600;
}

.related-date {
    display: flex;
    align-items: center;
    gap: 4px;
    color: #8e8e8e;
    font-size: 12px;
}

.related-lesson-title {
    margin-bottom: 16px;
}

.related-lesson-title a {
    text-decoration: none;
    color: #262626;
    font-size: 16px;
    font-weight: 600;
    line-height: 1.4;
    transition: color 0.2s ease;
}

.related-lesson-title a:hover {
    color: #0095f6;
}

.related-lesson-footer {
    display: flex;
    justify-content: flex-end;
}

.read-more {
    display: flex;
    align-items: center;
    gap: 6px;
    color: #0095f6;
    text-decoration: none;
    font-size: 14px;
    font-weight: 600;
    transition: all 0.2s ease;
}

.read-more:hover {
    color: #1877f2;
    transform: translateX(2px);
}

.footer {
    background: #fff;
    border-top: 1px solid #dbdbdb;
    padding: 20px 0;
    margin-top: 40px;
    text-align: center;
}

.footer-content p {
    font-size: 12px;
    color: #8e8e8e;
    margin-bottom: 4px;
}

@media (max-width: 768px) {
    html, body {
        overflow-x: hidden;
        max-width: 100%;
    }
    
    .container {
        padding: 0 16px;
        max-width: 100%;
        overflow-x: hidden;
    }
    
    /* Lesson səhifəsində container və main padding sil */
    .main:has(.lesson-page) .container {
        padding: 0 !important;
    }
    
    .page-header {
        padding: 0 16px;
    }
    
    .lessons-grid {
        padding: 0;
    }
    
    .main-layout {
        display: flex;
        flex-direction: column;
        gap: 16px;
        width: 100%;
        max-width: 100%;
    }
    
    .sidebar {
        /* position: fixed handled in mobile menu styles below */
    }
    
    .content-area {
        /* Mobile ad is now inline in each page's HTML */
        width: 100%;
        max-width: 100%;
        padding: 0;
    }
    
    /* Lesson səhifəsində content-area padding sil */
    .content-area:has(.lesson-page) {
        padding: 0 !important;
    }
    
    .header-content {
        padding: 0 16px;
        gap: 12px;
    }
}

.related-lessons-simple {
    padding: 24px 40px;
    background: #f8f9fa;
    border-top: 1px solid #e9ecef;
}

.related-lessons-simple .related-title {
    font-size: 18px;
    font-weight: 600;
    color: #262626;
    margin-bottom: 16px;
    text-align: left;
}

.related-lesson-link {
    border-radius: 8px;
    transition: all 0.2s ease;
}

.related-lesson-link:hover {
    transform: translateY(-1px);
}

.related-lesson-link a {
    color: #262626;
    text-decoration: none;
    font-size: 16px;
    font-weight: 500;
    line-height: 1.4;
    transition: color 0.2s ease;
}

.related-lesson-link a:hover {
    color: #0095f6;
}

@media (max-width: 768px) {
    .related-lessons-simple {
        padding: 20px;
    }
    
    .related-lessons-simple .related-title {
        font-size: 16px;
    }
    
    .related-lesson-link {
        padding: 14px 16px;
    }
    
    .related-lesson-link a {
        font-size: 15px;
    }
    
    .logo a span {
        display: none;
    }
    
    .search-box {
        margin: 0 8px;
        max-width: 200px;
    }
    
    .search-input {
        font-size: 13px;
    }
    
    .header-actions {
        gap: 8px;
    }
    
    .nav-link {
        width: 32px;
        height: 32px;
        font-size: 14px;
    }
    
    .lesson-page {
        max-width: 100%;
        margin: 0;
        width: 100%;
        border-radius: 0 !important;
        box-shadow: none !important;
    }
    
    .breadcrumb-nav {
        padding: 16px 20px;
        border-radius: 0 !important;
    }
    
    .lesson-page .lesson-header {
        padding: 24px 20px;
    }
    
    .lesson-page .lesson-title {
        font-size: 24px;
    }
    
    .lesson-body {
        padding: 24px 20px;
    }
    
    .lesson-actions {
        flex-direction: column;
        gap: 16px;
        align-items: stretch;
        padding: 20px;
    }
    
    .action-buttons {
        justify-content: center;
        flex-wrap: wrap;
    }
    
    .lesson-stats {
        justify-content: center;
    }
    
    .related-lessons {
        padding: 20px;
        border-radius: 0 !important;
    }
    
    .related-lessons-simple {
        border-radius: 0 !important;
    }
    
    .related-grid {
        grid-template-columns: 1fr;
    }
    
    .error-actions {
        flex-direction: column;
        align-items: center;
    }
}

@media (max-width: 480px) {
    .page-header h1 {
        font-size: 24px;
    }
    
    .lesson-page .lesson-title {
        font-size: 18px;
    }
    
    .error-content h1 {
        font-size: 48px;
    }
}

.back-to-top {
    position: fixed;
    bottom: 20px;
    right: 20px;
    width: 44px;
    height: 44px;
    border-radius: 50%;
    background: #0095f6;
    color: white;
    border: none;
    cursor: pointer;
    font-size: 18px;
    display: none;
    z-index: 1000;
    transition: all 0.3s ease;
    box-shadow: 0 2px 8px rgba(0,0,0,0.15);
}

.back-to-top:hover {
    background: #1877f2;
    transform: scale(1.1);
}

.reading-progress {
    position: fixed;
    top: 0;
    left: 0;
    width: 0%;
    height: 2px;
    background: #0095f6;
    z-index: 1001;
    transition: width 0.3s ease;
}

.menu-toggle {
    display: none;
}

.sidebar-header {
    display: none;
}

.sidebar-close {
    display: none;
}

.sidebar-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    z-index: 998;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
}

.sidebar-overlay.active {
    opacity: 1;
    visibility: visible;
}

@media (max-width: 768px) {
    .menu-toggle {
        display: flex !important;
    }
    
    .sidebar {
        position: fixed !important;
        top: 0;
        left: -100%;
        width: 280px;
        height: 100vh;
        z-index: 999;
        background: #fff;
        box-shadow: 2px 0 8px rgba(0,0,0,0.1);
        transition: left 0.3s ease;
        order: 0 !important;
        overflow-y: auto;
    }
    
    .sidebar.active {
        left: 0;
    }
    
    .sidebar-header {
        display: flex;
        justify-content: space-between;
        align-items: center;
        padding: 20px;
        border-bottom: 1px solid #eee;
        position: sticky;
        top: 0;
        background: transparent;
        z-index: 10;
    }
    
    .sidebar-title {
        margin: 0;
        font-size: 18px;
    }
    
    .sidebar-close {
        display: flex;
        width: 32px;
        height: 32px;
        border: none;
        background: #f0f0f0;
        border-radius: 6px;
        align-items: center;
        justify-content: center;
        cursor: pointer;
        transition: all 0.2s ease;
    }
    
    .sidebar-close:hover {
        background: #e0e0e0;
    }
    
    .sidebar-close i {
        color: #333;
        font-size: 16px;
    }
    
    .sidebar-content {
        padding: 20px !important;
    }
    
}

.sidebar-title-desktop {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 16px;
    font-weight: 600;
    color: #262626;
    padding: 20px;
    margin: 0;
    border-bottom: 1px solid #eee;
}

.sidebar-title-desktop i {
    color: #0095f6;
    font-size: 18px;
}

@media (max-width: 768px) {
    .sidebar-title-desktop {
        display: none;
    }
}