:root {
    --primary: #4F46E5;
    --primary-light: #6366F1;
    --primary-dark: #4338CA;
    --secondary: #7C3AED;
    --secondary-light: #8B5CF6;
    --secondary-dark: #6D28D9;
    --accent: #EC4899;
    --success: #10B981;
    --warning: #F59E0B;
    --danger: #EF4444;
    --info: #3B82F6;
    --bg-primary: #F9FAFB;
    --bg-secondary: #F3F4F6;
    --bg-card: #FFFFFF;
    --text-primary: #111827;
    --text-secondary: #6B7280;
    --text-muted: #9CA3AF;
    --border-color: #E5E7EB;
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --transition-fast: 0.15s ease;
    --transition-normal: 0.3s ease;
    --transition-slow: 0.5s ease;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, 'Noto Sans SC', sans-serif;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

main {
    flex: 1;
}

::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: var(--bg-secondary);
}

::-webkit-scrollbar-thumb {
    background: var(--text-muted);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--text-secondary);
}

.navbar-dark.bg-dark {
    background-color: #1F2937 !important;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.15);
}

.navbar-dark .navbar-brand {
    font-size: 1.35rem;
    letter-spacing: -0.025em;
}

.navbar-dark .nav-link {
    font-weight: 500;
    padding: 0.5rem 0.85rem !important;
    border-radius: var(--radius-sm);
    transition: background-color var(--transition-fast), color var(--transition-fast);
}

.navbar-dark .nav-link:hover,
.navbar-dark .nav-link.active {
    background-color: rgba(255, 255, 255, 0.1);
    color: #fff !important;
}

.navbar-dark .dropdown-menu {
    border: none;
    box-shadow: var(--shadow-lg);
    border-radius: var(--radius-md);
    overflow: hidden;
}

.navbar-dark .dropdown-item {
    padding: 0.55rem 1.2rem;
    font-size: 0.9rem;
    transition: background-color var(--transition-fast);
}

.navbar-dark .dropdown-item:hover {
    background-color: var(--bg-secondary);
}

.hero-section {
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    color: #fff;
    padding: 4rem 0;
    margin-bottom: 2rem;
    position: relative;
    overflow: hidden;
}

.hero-section::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -20%;
    width: 600px;
    height: 600px;
    background: rgba(255, 255, 255, 0.05);
    border-radius: 50%;
}

.hero-section::after {
    content: '';
    position: absolute;
    bottom: -30%;
    left: -10%;
    width: 400px;
    height: 400px;
    background: rgba(255, 255, 255, 0.03);
    border-radius: 50%;
}

.hero-section h1 {
    font-size: 2.5rem;
    font-weight: 700;
    letter-spacing: -0.025em;
    margin-bottom: 1rem;
}

.hero-section p {
    font-size: 1.15rem;
    opacity: 0.9;
    max-width: 600px;
}

.card {
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
    overflow: hidden;
    background: var(--bg-card);
}

.article-card:hover,
.category-card:hover,
.tag-cloud-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-xl);
}

.article-card {
    height: 100%;
    display: flex;
    flex-direction: column;
    transition: transform var(--transition-normal), box-shadow var(--transition-normal);
}

.article-card .card-body {
    flex: 1;
    display: flex;
    flex-direction: column;
}

.article-card .cover-wrapper {
    position: relative;
    overflow: hidden;
    aspect-ratio: 16 / 9;
}

.article-card .cover-wrapper img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform var(--transition-slow);
}

.article-card:hover .cover-wrapper img {
    transform: scale(1.05);
}

.article-card .cover-overlay {
    position: absolute;
    inset: 0;
    background: linear-gradient(to top, rgba(0, 0, 0, 0.5) 0%, transparent 50%);
    opacity: 0;
    transition: opacity var(--transition-normal);
}

.article-card:hover .cover-overlay {
    opacity: 1;
}

.article-card .card-title {
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
    line-height: 1.4;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.article-card .card-title a {
    color: var(--text-primary);
    text-decoration: none;
    transition: color var(--transition-fast);
}

.article-card .card-title a:hover {
    color: var(--primary);
}

.article-card .card-text {
    color: var(--text-secondary);
    font-size: 0.9rem;
    line-height: 1.6;
    display: -webkit-box;
    -webkit-line-clamp: 3;
    -webkit-box-orient: vertical;
    overflow: hidden;
    flex: 1;
}

.article-card .card-meta {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-top: auto;
    padding-top: 0.75rem;
    font-size: 0.8rem;
    color: var(--text-muted);
}

.article-card .card-meta i {
    margin-right: 0.25rem;
}

.badge-category {
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-light) 100%);
    color: #fff;
    font-weight: 500;
    padding: 0.35em 0.75em;
    border-radius: var(--radius-sm);
    font-size: 0.75rem;
    text-decoration: none;
    transition: opacity var(--transition-fast);
}

.badge-category:hover {
    opacity: 0.85;
    color: #fff;
}

.badge-tag {
    background-color: var(--bg-secondary);
    color: var(--text-secondary);
    font-weight: 500;
    padding: 0.3em 0.65em;
    border-radius: var(--radius-sm);
    font-size: 0.75rem;
    text-decoration: none;
    border: 1px solid var(--border-color);
    transition: all var(--transition-fast);
}

.badge-tag:hover {
    background-color: var(--primary);
    color: #fff;
    border-color: var(--primary);
}

.tags-cloud .badge-tag {
    margin: 0.2rem;
    display: inline-block;
}

.flash-message {
    animation: slideDown 0.4s ease-out;
    border-radius: var(--radius-md);
    border: none;
    box-shadow: var(--shadow-md);
}

@keyframes slideDown {
    from {
        opacity: 0;
        transform: translateY(-20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes fadeOut {
    from {
        opacity: 1;
    }
    to {
        opacity: 0;
        transform: translateY(-10px);
    }
}

.flash-message.hiding {
    animation: fadeOut 0.4s ease-in forwards;
}

.modal-content {
    border: none;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-xl);
}

.modal-header {
    border-bottom: 1px solid var(--border-color);
    padding: 1.25rem 1.5rem;
}

.modal-body {
    padding: 1.5rem;
}

.modal-footer {
    border-top: 1px solid var(--border-color);
    padding: 1rem 1.5rem;
}

.floating-window {
    position: fixed;
    z-index: 1050;
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-xl);
    border: 1px solid var(--border-color);
    max-width: 400px;
    width: 90%;
}

.floating-window-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1rem 1.25rem;
    border-bottom: 1px solid var(--border-color);
    font-weight: 600;
}

.floating-window-body {
    padding: 1.25rem;
}

.floating-window-footer {
    padding: 0.75rem 1.25rem;
    border-top: 1px solid var(--border-color);
    text-align: right;
}

.admin-table {
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--border-color);
}

.admin-table thead {
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-light) 100%);
    color: #fff;
}

.admin-table thead th {
    font-weight: 600;
    font-size: 0.85rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    padding: 0.85rem 1rem;
    border: none;
    white-space: nowrap;
}

.admin-table tbody td {
    padding: 0.75rem 1rem;
    vertical-align: middle;
    font-size: 0.9rem;
    border-color: var(--border-color);
}

.admin-table tbody tr {
    transition: background-color var(--transition-fast);
}

.admin-table tbody tr:hover {
    background-color: var(--bg-secondary);
}

.extraction-code {
    font-family: 'Courier New', Courier, monospace;
    background-color: var(--bg-secondary);
    padding: 0.2em 0.5em;
    border-radius: var(--radius-sm);
    font-size: 0.9rem;
    letter-spacing: 0.05em;
    border: 1px solid var(--border-color);
}

.extraction-code-card {
    border-left: 4px solid var(--primary);
}

.extraction-code-card .code-value {
    font-family: 'Courier New', Courier, monospace;
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--primary);
    letter-spacing: 0.1em;
}

.extraction-code-card .code-meta {
    font-size: 0.8rem;
    color: var(--text-muted);
}

.extraction-code-card .code-status {
    display: inline-flex;
    align-items: center;
    gap: 0.35rem;
}

.extraction-code-card .code-status .dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    display: inline-block;
}

.extraction-code-card .code-status .dot.active {
    background-color: var(--success);
}

.extraction-code-card .code-status .dot.used {
    background-color: var(--warning);
}

.extraction-code-card .code-status .dot.expired {
    background-color: var(--danger);
}

.btn-back-to-top {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    width: 44px;
    height: 44px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    visibility: hidden;
    transition: opacity var(--transition-normal), visibility var(--transition-normal), transform var(--transition-normal);
    z-index: 1040;
    box-shadow: var(--shadow-lg);
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    border: none;
}

.btn-back-to-top.visible {
    opacity: 1;
    visibility: visible;
}

.btn-back-to-top:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-xl);
}

.pagination .page-link {
    color: var(--primary);
    border-radius: var(--radius-sm);
    margin: 0 0.15rem;
    border: 1px solid var(--border-color);
    font-weight: 500;
    transition: all var(--transition-fast);
}

.pagination .page-link:hover {
    background-color: var(--primary);
    border-color: var(--primary);
    color: #fff;
    transform: translateY(-1px);
}

.pagination .page-item.active .page-link {
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    border-color: var(--primary);
    color: #fff;
}

.pagination .page-item.disabled .page-link {
    color: var(--text-muted);
    background-color: var(--bg-secondary);
}

.form-control,
.form-select {
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 0.6rem 1rem;
    font-size: 0.95rem;
    transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.form-control:focus,
.form-select:focus {
    border-color: var(--primary-light);
    box-shadow: 0 0 0 0.2rem rgba(79, 70, 229, 0.15);
}

.form-label {
    font-weight: 500;
    font-size: 0.9rem;
    color: var(--text-primary);
    margin-bottom: 0.4rem;
}

.form-text {
    font-size: 0.8rem;
    color: var(--text-muted);
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-light) 100%);
    border: none;
    font-weight: 500;
    padding: 0.55rem 1.5rem;
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
}

.btn-primary:hover {
    background: linear-gradient(135deg, var(--primary-dark) 0%, var(--primary) 100%);
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

.btn-secondary {
    background: linear-gradient(135deg, var(--secondary) 0%, var(--secondary-light) 100%);
    border: none;
    font-weight: 500;
    padding: 0.55rem 1.5rem;
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
}

.btn-secondary:hover {
    background: linear-gradient(135deg, var(--secondary-dark) 0%, var(--secondary) 100%);
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

.btn-outline-primary {
    color: var(--primary);
    border-color: var(--primary);
    font-weight: 500;
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
}

.btn-outline-primary:hover {
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-light) 100%);
    border-color: var(--primary);
    transform: translateY(-1px);
}

.site-footer {
    background-color: #1F2937;
    color: #D1D5DB;
    padding: 2rem 0;
    margin-top: auto;
}

.site-footer a {
    color: var(--primary-light);
    text-decoration: none;
}

.site-footer a:hover {
    color: #fff;
}

.section-title {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 1.5rem;
    position: relative;
    padding-bottom: 0.5rem;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 50px;
    height: 3px;
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    border-radius: 2px;
}

.empty-state {
    text-align: center;
    padding: 3rem 1rem;
    color: var(--text-muted);
}

.empty-state i {
    font-size: 3rem;
    margin-bottom: 1rem;
    display: block;
}

.empty-state p {
    font-size: 1.1rem;
}

@media (max-width: 767.98px) {
    .hero-section {
        padding: 2.5rem 0;
    }

    .hero-section h1 {
        font-size: 1.75rem;
    }

    .hero-section p {
        font-size: 1rem;
    }

    .article-card .card-title {
        font-size: 1rem;
    }

    .btn-back-to-top {
        bottom: 1.25rem;
        right: 1.25rem;
        width: 40px;
        height: 40px;
    }

    .section-title {
        font-size: 1.25rem;
    }

    .admin-table {
        font-size: 0.85rem;
    }

    .admin-table thead th,
    .admin-table tbody td {
        padding: 0.5rem 0.65rem;
    }
}

@media (max-width: 575.98px) {
    .navbar-dark .nav-link {
        padding: 0.4rem 0.6rem !important;
    }

    .card {
        border-radius: var(--radius-md);
    }

    .pagination .page-link {
        padding: 0.35rem 0.6rem;
        font-size: 0.85rem;
    }
}

.admin-sidebar .nav {
    flex-direction: column;
}
.admin-sidebar .nav-link {
    color: #495057;
    padding: 0.65rem 1rem;
    border-left: 3px solid transparent;
    transition: all 0.2s ease;
}
.admin-sidebar .nav-link:hover {
    color: #0d6efd;
    background-color: rgba(13, 110, 253, 0.05);
    border-left-color: rgba(13, 110, 253, 0.3);
}
.admin-sidebar .nav-link.active {
    color: #0d6efd;
    background-color: rgba(13, 110, 253, 0.1);
    border-left-color: #0d6efd;
    font-weight: 600;
}
@media (max-width: 991.98px) {
    .admin-sidebar .nav {
        flex-direction: row;
        flex-wrap: nowrap;
        overflow-x: auto;
        -webkit-overflow-scrolling: touch;
    }
    .admin-sidebar .nav-link {
        border-left: none;
        border-bottom: 3px solid transparent;
        white-space: nowrap;
        padding: 0.5rem 0.75rem;
    }
    .admin-sidebar .nav-link:hover {
        border-left-color: transparent;
        border-bottom-color: rgba(13, 110, 253, 0.3);
    }
    .admin-sidebar .nav-link.active {
        border-left-color: transparent;
        border-bottom-color: #0d6efd;
    }
}