/* ============================================
   OpenAlex Research Database
   Public Pages Theme - Light, Modern, Academic
   ============================================ */

/* Google Fonts */
@import url('https://fonts.googleapis.com/css2?family=Libre+Baskerville:ital,wght@0,400;0,700;1,400&family=Source+Sans+3:ital,wght@0,300;0,400;0,500;0,600;0,700;1,400&family=JetBrains+Mono:wght@400;500&display=swap');

/* ============================================
   CSS Variables
   ============================================ */
:root {
    /* Colors */
    --color-primary: #1e3a5f;
    --color-primary-light: #2d5a87;
    --color-primary-dark: #0f2640;
    --color-accent: #0066cc;
    --color-accent-light: #3d8fea;
    --color-success: #198754;
    --color-warning: #fd7e14;
    --color-danger: #dc3545;
    --color-info: #0dcaf0;
    
    /* Backgrounds */
    --bg-body: #f8fafc;
    --bg-white: #ffffff;
    --bg-light: #f1f5f9;
    --bg-hero: linear-gradient(135deg, #1e3a5f 0%, #2d5a87 50%, #0066cc 100%);
    
    /* Text */
    --text-primary: #1e293b;
    --text-secondary: #475569;
    --text-muted: #64748b;
    --text-light: #94a3b8;
    --text-inverse: #ffffff;
    
    /* Borders */
    --border-light: #e2e8f0;
    --border-medium: #cbd5e1;
    
    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1);
    --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1);
    
    /* Typography */
    --font-heading: 'Libre Baskerville', Georgia, serif;
    --font-body: 'Source Sans 3', -apple-system, sans-serif;
    --font-mono: 'JetBrains Mono', monospace;
    
    /* Spacing */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
    --spacing-3xl: 4rem;
    
    /* Border Radius */
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;
    --radius-xl: 16px;
    --radius-full: 9999px;
    
    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-normal: 250ms ease;
    --transition-slow: 350ms ease;
}

/* ============================================
   Base Styles
   ============================================ */
*, *::before, *::after {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-body);
    font-size: 1rem;
    line-height: 1.7;
    color: var(--text-primary);
    background-color: var(--bg-body);
    margin: 0;
    padding: 0;
    min-height: 100vh;
    -webkit-font-smoothing: antialiased;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-heading);
    font-weight: 700;
    line-height: 1.3;
    color: var(--text-primary);
    margin-top: 0;
}

h1 { font-size: 2.5rem; }
h2 { font-size: 2rem; }
h3 { font-size: 1.5rem; }
h4 { font-size: 1.25rem; }
h5 { font-size: 1.125rem; }
h6 { font-size: 1rem; }

p {
    margin-top: 0;
    margin-bottom: var(--spacing-md);
}

a {
    color: var(--color-accent);
    text-decoration: none;
    transition: color var(--transition-fast);
}

a:hover {
    color: var(--color-primary);
    text-decoration: underline;
}

/* ============================================
   Navbar
   ============================================ */
.navbar {
    background: var(--bg-white);
    border-bottom: 1px solid var(--border-light);
    box-shadow: var(--shadow-sm);
    padding: var(--spacing-md) 0;
    z-index: 1000;
}

.navbar-brand {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    text-decoration: none;
}

.navbar-brand .brand-logo {
    height: 60px;
    width: auto;
    object-fit: contain;
}

.navbar-brand .brand-icon {
    font-size: 1.75rem;
    color: var(--color-primary);
}

.navbar-brand .brand-text {
    font-family: var(--font-heading);
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--color-primary);
}

.navbar-brand .brand-subtitle {
    font-size: 0.75rem;
    color: var(--text-muted);
    display: block;
    margin-top: -4px;
}

.navbar-nav .nav-link {
    font-weight: 500;
    color: var(--text-secondary);
    padding: var(--spacing-sm) var(--spacing-md);
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    transition: color var(--transition-fast);
}

.navbar-nav .nav-link:hover,
.navbar-nav .nav-link.active {
    color: var(--color-primary);
}

.navbar-nav .nav-link.active {
    font-weight: 600;
}

.nav-search .input-group {
    width: 280px;
}

.nav-search .form-control {
    border-radius: var(--radius-full) 0 0 var(--radius-full);
    border-color: var(--border-medium);
}

.nav-search .btn {
    border-radius: 0 var(--radius-full) var(--radius-full) 0;
}

/* ============================================
   Hero Section
   ============================================ */
.hero {
    background: var(--bg-hero);
    color: var(--text-inverse);
    padding: var(--spacing-3xl) 0;
    text-align: center;
}

.hero-title {
    font-size: 3rem;
    font-weight: 700;
    margin-bottom: var(--spacing-md);
    color: var(--text-inverse);
}

.hero-subtitle {
    font-size: 1.25rem;
    opacity: 0.9;
    max-width: 600px;
    margin: 0 auto var(--spacing-xl);
}

.hero-search {
    max-width: 600px;
    margin: 0 auto;
}

.hero-search .input-group {
    background: var(--bg-white);
    border-radius: var(--radius-full);
    overflow: hidden;
    box-shadow: var(--shadow-lg);
}

.hero-search .form-control {
    border: none;
    padding: var(--spacing-md) var(--spacing-lg);
    font-size: 1.125rem;
}

.hero-search .form-control:focus {
    box-shadow: none;
}

.hero-search .btn {
    padding: var(--spacing-md) var(--spacing-xl);
    font-size: 1.125rem;
}

/* ============================================
   Stats Section
   ============================================ */
.stats-section {
    padding: var(--spacing-2xl) 0;
    background: var(--bg-white);
    margin-top: -40px;
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-lg);
    position: relative;
    z-index: 10;
}

.stat-counter {
    text-align: center;
    padding: var(--spacing-lg);
}

.stat-counter-icon {
    font-size: 2.5rem;
    color: var(--color-accent);
    margin-bottom: var(--spacing-sm);
}

.stat-counter-value {
    font-family: var(--font-heading);
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--color-primary);
    line-height: 1.2;
}

.stat-counter-label {
    font-size: 0.9375rem;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

/* ============================================
   Section Styles
   ============================================ */
.section {
    padding: var(--spacing-3xl) 0;
}

.section-title {
    font-size: 1.75rem;
    margin-bottom: var(--spacing-xs);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.section-title i {
    color: var(--color-accent);
}

.section-subtitle {
    color: var(--text-muted);
    margin-bottom: var(--spacing-xl);
}

.section-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-end;
    margin-bottom: var(--spacing-xl);
}

.view-all-link {
    font-weight: 500;
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
}

/* ============================================
   Cards - Publications
   ============================================ */
.publication-card {
    background: var(--bg-white);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    margin-bottom: var(--spacing-md);
    transition: all var(--transition-normal);
}

.publication-card:hover {
    border-color: var(--color-accent);
    box-shadow: var(--shadow-md);
    transform: translateY(-2px);
}

.publication-card-title {
    font-family: var(--font-body);
    font-size: 1.125rem;
    font-weight: 600;
    margin-bottom: var(--spacing-sm);
    line-height: 1.4;
}

.publication-card-title a {
    color: var(--text-primary);
}

.publication-card-title a:hover {
    color: var(--color-accent);
    text-decoration: none;
}

.publication-card-authors {
    font-size: 0.9375rem;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-sm);
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    flex-wrap: wrap;
}

.publication-card-authors i {
    color: var(--text-light);
}

.publication-card-authors a {
    color: var(--text-secondary);
}

.publication-card-authors a:hover {
    color: var(--color-accent);
}

.publication-card-abstract {
    font-size: 0.9375rem;
    color: var(--text-muted);
    margin-bottom: var(--spacing-md);
    line-height: 1.6;
}

.publication-card-meta {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-md);
    font-size: 0.8125rem;
    color: var(--text-muted);
}

.publication-card-meta .meta-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
}

.publication-card-meta .citation-count {
    color: var(--color-warning);
    font-weight: 600;
}

.publication-card-meta .open-access {
    color: var(--color-success);
    font-weight: 500;
}

/* ============================================
   Cards - Authors
   ============================================ */
.author-card {
    background: var(--bg-white);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    display: flex;
    gap: var(--spacing-md);
    transition: all var(--transition-normal);
}

.author-card:hover {
    border-color: var(--color-accent);
    box-shadow: var(--shadow-md);
}

.author-card-avatar {
    font-size: 3rem;
    color: var(--color-primary-light);
    flex-shrink: 0;
}

.author-card-body {
    flex: 1;
    min-width: 0;
}

.author-card-name {
    font-family: var(--font-body);
    font-size: 1.125rem;
    font-weight: 600;
    margin-bottom: var(--spacing-xs);
}

.author-card-name a {
    color: var(--text-primary);
}

.author-card-name a:hover {
    color: var(--color-accent);
    text-decoration: none;
}

.author-card-institution {
    font-size: 0.9375rem;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-sm);
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
}

.author-card-institution i {
    color: var(--text-light);
}

.author-card-stats {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-sm);
}

.stat-badge {
    background: var(--bg-light);
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--radius-sm);
    font-size: 0.8125rem;
    color: var(--text-secondary);
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
}

.stat-badge.h-index {
    background: var(--color-primary);
    color: var(--text-inverse);
}

/* ============================================
   Cards - Institutions
   ============================================ */
.institution-card {
    background: var(--bg-white);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    display: flex;
    gap: var(--spacing-md);
    transition: all var(--transition-normal);
}

.institution-card:hover {
    border-color: var(--color-accent);
    box-shadow: var(--shadow-md);
}

.institution-card-icon {
    width: 56px;
    height: 56px;
    background: linear-gradient(135deg, var(--color-primary), var(--color-accent));
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-inverse);
    font-size: 1.5rem;
    flex-shrink: 0;
}

.institution-card-body {
    flex: 1;
    min-width: 0;
}

.institution-card-name {
    font-family: var(--font-body);
    font-size: 1.125rem;
    font-weight: 600;
    margin-bottom: var(--spacing-xs);
}

.institution-card-name a {
    color: var(--text-primary);
}

.institution-card-name a:hover {
    color: var(--color-accent);
    text-decoration: none;
}

.institution-card-location {
    font-size: 0.9375rem;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-sm);
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-md);
}

.location-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
}

.institution-card-stats {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-sm);
}

/* ============================================
   Breadcrumb
   ============================================ */
.breadcrumb-nav {
    background: var(--bg-white);
    border-bottom: 1px solid var(--border-light);
    padding: var(--spacing-sm) 0;
}

.breadcrumb {
    margin: 0;
    padding: 0;
    list-style: none;
    display: flex;
    align-items: center;
    font-size: 0.875rem;
}

.breadcrumb-item + .breadcrumb-item::before {
    content: "/";
    color: var(--text-light);
    padding: 0 var(--spacing-sm);
}

.breadcrumb-item a {
    color: var(--text-muted);
}

.breadcrumb-item a:hover {
    color: var(--color-accent);
}

.breadcrumb-item.active {
    color: var(--text-primary);
    font-weight: 500;
}

/* ============================================
   Pagination
   ============================================ */
.pagination-nav {
    margin-top: var(--spacing-xl);
    padding-top: var(--spacing-lg);
    border-top: 1px solid var(--border-light);
}

.pagination-info {
    font-size: 0.9375rem;
    color: var(--text-muted);
}

.pagination {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    margin: 0;
    padding: 0;
    list-style: none;
}

.page-item .page-link {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    padding: var(--spacing-sm) var(--spacing-md);
    font-size: 0.9375rem;
    color: var(--text-secondary);
    background: var(--bg-white);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-md);
    text-decoration: none;
    transition: all var(--transition-fast);
}

.page-item .page-link:hover {
    background: var(--bg-light);
    border-color: var(--border-medium);
    color: var(--text-primary);
}

.page-item.active .page-link {
    background: var(--color-primary);
    border-color: var(--color-primary);
    color: var(--text-inverse);
}

.page-item.disabled .page-link {
    background: var(--bg-light);
    color: var(--text-light);
    cursor: not-allowed;
}

/* ============================================
   Social Share
   ============================================ */
.social-share {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.share-label {
    font-size: 0.875rem;
    color: var(--text-muted);
    font-weight: 500;
}

.share-btn {
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius-full);
    border: 1px solid var(--border-light);
    background: var(--bg-white);
    color: var(--text-secondary);
    text-decoration: none;
    transition: all var(--transition-fast);
    cursor: pointer;
}

.share-btn:hover {
    transform: translateY(-2px);
}

.share-btn.twitter:hover {
    background: #1da1f2;
    border-color: #1da1f2;
    color: white;
}

.share-btn.linkedin:hover {
    background: #0077b5;
    border-color: #0077b5;
    color: white;
}

.share-btn.facebook:hover {
    background: #1877f2;
    border-color: #1877f2;
    color: white;
}

.share-btn.copy:hover {
    background: var(--color-primary);
    border-color: var(--color-primary);
    color: white;
}

/* ============================================
   Detail Pages
   ============================================ */
.detail-header {
    background: var(--bg-white);
    border-bottom: 1px solid var(--border-light);
    padding: var(--spacing-2xl) 0;
}

.detail-title {
    font-size: 2rem;
    margin-bottom: var(--spacing-md);
}

.detail-meta {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-lg);
    font-size: 0.9375rem;
    color: var(--text-secondary);
}

.detail-meta .meta-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
}

.detail-content {
    padding: var(--spacing-2xl) 0;
}

.detail-section {
    background: var(--bg-white);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    margin-bottom: var(--spacing-lg);
}

.detail-section-title {
    font-size: 1.25rem;
    margin-bottom: var(--spacing-md);
    padding-bottom: var(--spacing-sm);
    border-bottom: 2px solid var(--color-accent);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.detail-section-title i {
    color: var(--color-accent);
}

/* ============================================
   Filter Bar
   ============================================ */
.filter-bar {
    background: var(--bg-white);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    margin-bottom: var(--spacing-lg);
}

.filter-bar .form-label {
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-xs);
}

.filter-bar .form-control,
.filter-bar .form-select {
    border-color: var(--border-medium);
    border-radius: var(--radius-md);
}

.filter-bar .form-control:focus,
.filter-bar .form-select:focus {
    border-color: var(--color-accent);
    box-shadow: 0 0 0 3px rgba(0, 102, 204, 0.1);
}

/* ============================================
   Empty State
   ============================================ */
.empty-state {
    text-align: center;
    padding: var(--spacing-3xl);
    color: var(--text-muted);
}

.empty-state i {
    font-size: 4rem;
    color: var(--text-light);
    margin-bottom: var(--spacing-lg);
    display: block;
}

.empty-state h4 {
    color: var(--text-secondary);
    margin-bottom: var(--spacing-sm);
}

/* ============================================
   Footer
   ============================================ */
.site-footer {
    background: var(--color-primary-dark);
    color: var(--text-inverse);
    padding: var(--spacing-3xl) 0 var(--spacing-lg);
    margin-top: var(--spacing-3xl);
}

.footer-brand {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-family: var(--font-heading);
    font-size: 1.25rem;
    font-weight: 700;
    margin-bottom: var(--spacing-md);
}

.footer-brand i {
    font-size: 1.5rem;
}

.footer-brand img {
    height: 50px;
    width: auto;
    object-fit: contain;
    vertical-align: middle;
}

.footer-desc {
    font-size: 0.9375rem;
    opacity: 0.8;
    line-height: 1.7;
    margin-bottom: var(--spacing-md);
}

.footer-social {
    display: flex;
    gap: var(--spacing-sm);
}

.footer-social a {
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(255, 255, 255, 0.1);
    border-radius: var(--radius-full);
    color: var(--text-inverse);
    font-size: 1.125rem;
    transition: all var(--transition-fast);
}

.footer-social a:hover {
    background: var(--color-accent);
    transform: translateY(-2px);
}

.footer-title {
    font-family: var(--font-body);
    font-size: 0.875rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: var(--spacing-md);
    color: var(--text-inverse);
}

.footer-links {
    list-style: none;
    margin: 0;
    padding: 0;
}

.footer-links li {
    margin-bottom: var(--spacing-sm);
}

.footer-links a {
    color: rgba(255, 255, 255, 0.7);
    font-size: 0.9375rem;
    transition: color var(--transition-fast);
}

.footer-links a:hover {
    color: var(--text-inverse);
    text-decoration: none;
}

.footer-divider {
    border-color: rgba(255, 255, 255, 0.1);
    margin: var(--spacing-2xl) 0 var(--spacing-lg);
}

.footer-bottom {
    text-align: center;
    font-size: 0.875rem;
    opacity: 0.7;
}

.footer-bottom a {
    color: var(--text-inverse);
    text-decoration: underline;
}

/* ============================================
   Utilities
   ============================================ */
.text-primary { color: var(--text-primary) !important; }
.text-secondary { color: var(--text-secondary) !important; }
.text-muted { color: var(--text-muted) !important; }
.text-accent { color: var(--color-accent) !important; }

.bg-light { background-color: var(--bg-light) !important; }
.bg-white { background-color: var(--bg-white) !important; }

/* Animations */
@keyframes countUp {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

.animate-in {
    animation: fadeIn 0.5s ease forwards;
}

/* ============================================
   Responsive
   ============================================ */
@media (max-width: 991px) {
    .hero-title {
        font-size: 2rem;
    }
    
    .nav-search .input-group {
        width: 100%;
        margin-top: var(--spacing-md);
    }
    
    .stats-section {
        margin-top: 0;
        border-radius: 0;
    }
}

@media (max-width: 767px) {
    .hero {
        padding: var(--spacing-2xl) 0;
    }
    
    .hero-title {
        font-size: 1.75rem;
    }
    
    .hero-subtitle {
        font-size: 1rem;
    }
    
    .section {
        padding: var(--spacing-2xl) 0;
    }
    
    .section-header {
        flex-direction: column;
        align-items: flex-start;
        gap: var(--spacing-md);
    }
    
    .detail-title {
        font-size: 1.5rem;
    }
    
    .pagination-nav {
        flex-direction: column;
        gap: var(--spacing-md);
        align-items: center;
    }
    
    .author-card,
    .institution-card {
        flex-direction: column;
        text-align: center;
    }
    
    .author-card-avatar,
    .institution-card-icon {
        margin: 0 auto;
    }
    
    .author-card-institution,
    .institution-card-location,
    .author-card-stats,
    .institution-card-stats {
        justify-content: center;
    }
}

/* ============================================
   Chart Container
   ============================================ */
.chart-container {
    position: relative;
    height: 300px;
    width: 100%;
}

/* ============================================
   Badge Styles
   ============================================ */
.badge-primary {
    background-color: var(--color-primary);
    color: white;
}

.badge-success {
    background-color: var(--color-success);
    color: white;
}

.badge-warning {
    background-color: var(--color-warning);
    color: white;
}

.badge-info {
    background-color: var(--color-info);
    color: var(--text-primary);
}

/* ============================================
   Copy to Clipboard Function
   ============================================ */
.copy-success {
    background: var(--color-success) !important;
    border-color: var(--color-success) !important;
    color: white !important;
}