/**
 * Main Stylesheet
 * International Journal of Nutrition, Dietetics & Health
 * Clean, Modern Academic Design
 */

/* ========================================
   CSS Variables
======================================== */
:root {
    /* Colors */
    --primary-color: #1a472a;
    --primary-light: #2d6a4f;
    --primary-dark: #0d2818;
    --secondary-color: #c9a227;
    --secondary-light: #d4b545;
    
    --text-color: #2c3e50;
    --text-light: #5d6d7e;
    --text-muted: #8e99a4;
    
    --bg-color: #ffffff;
    --bg-light: #f8f9fa;
    --bg-accent: #f0f4f1;
    
    --border-color: #e0e5e9;
    --border-light: #eef1f3;
    
    --success-color: #28a745;
    --warning-color: #ffc107;
    --danger-color: #dc3545;
    --info-color: #17a2b8;
    
    /* Typography */
    --font-serif: 'Crimson Pro', Georgia, 'Times New Roman', serif;
    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    
    /* 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;
    
    /* Shadows */
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.08);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.12);
    
    /* Transitions */
    --transition-fast: 0.15s ease;
    --transition-normal: 0.25s ease;
}

/* ========================================
   Reset & Base
======================================== */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    font-size: 16px;
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-sans);
    font-size: 1rem;
    line-height: 1.6;
    color: var(--text-color);
    background-color: var(--bg-color);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-serif);
    font-weight: 600;
    line-height: 1.3;
    color: var(--primary-dark);
    margin-bottom: var(--spacing-md);
}

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-bottom: var(--spacing-md);
}

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

a:hover {
    color: var(--primary-light);
}

img {
    max-width: 100%;
    height: auto;
}

ul, ol {
    margin-bottom: var(--spacing-md);
    padding-left: var(--spacing-lg);
}

/* ========================================
   Container
======================================== */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
}

/* ========================================
   Top Bar
======================================== */
.top-bar {
    background-color: var(--primary-dark);
    color: white;
    font-size: 0.875rem;
    padding: var(--spacing-sm) 0;
}

.top-bar-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.top-bar a {
    color: rgba(255, 255, 255, 0.85);
}

.top-bar a:hover {
    color: white;
}

.top-links {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.top-links .divider {
    color: rgba(255, 255, 255, 0.3);
}

/* ========================================
   Header
======================================== */
.main-header {
    background-color: var(--bg-color);
    border-bottom: 1px solid var(--border-color);
    padding: var(--spacing-lg) 0;
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo a {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    text-decoration: none;
}

.logo-icon {
    width: 60px;
    height: 60px;
    background: linear-gradient(135deg, var(--primary-color), var(--primary-light));
    color: white;
    font-family: var(--font-serif);
    font-weight: 700;
    font-size: 1rem;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius-md);
}

.logo-text {
    display: flex;
    flex-direction: column;
}

.journal-name {
    font-family: var(--font-serif);
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--primary-dark);
    line-height: 1.2;
}

.journal-tagline {
    font-size: 0.8125rem;
    color: var(--text-light);
}

.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: var(--spacing-sm);
}

.mobile-menu-toggle span {
    width: 24px;
    height: 2px;
    background-color: var(--text-color);
    transition: var(--transition-fast);
}

/* ========================================
   Navigation
======================================== */
.main-nav {
    background-color: var(--primary-color);
    position: sticky;
    top: 0;
    z-index: 100;
}

.nav-menu {
    display: flex;
    list-style: none;
    margin: 0;
    padding: 0;
}

.nav-menu li a {
    display: block;
    padding: var(--spacing-md) var(--spacing-lg);
    color: rgba(255, 255, 255, 0.9);
    font-size: 0.9375rem;
    font-weight: 500;
    transition: background-color var(--transition-fast);
}

.nav-menu li a:hover,
.nav-menu li a.active {
    background-color: var(--primary-light);
    color: white;
}

/* ========================================
   Hero Section
======================================== */
.hero {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-dark) 100%);
    color: white;
    padding: var(--spacing-3xl) 0;
    text-align: center;
}

.hero-content {
    max-width: 800px;
    margin: 0 auto;
}

.hero h1 {
    color: white;
    font-size: 2.75rem;
    margin-bottom: var(--spacing-md);
}

.hero-subtitle {
    font-size: 1.25rem;
    opacity: 0.9;
    margin-bottom: var(--spacing-lg);
}

.hero-meta {
    display: flex;
    justify-content: center;
    gap: var(--spacing-xl);
    margin-bottom: var(--spacing-xl);
    font-size: 0.9375rem;
}

.hero-meta .issn {
    opacity: 0.85;
}

.hero-buttons {
    display: flex;
    justify-content: center;
    gap: var(--spacing-md);
    flex-wrap: wrap;
}

/* ========================================
   Buttons
======================================== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-sm) var(--spacing-lg);
    font-family: var(--font-sans);
    font-size: 0.9375rem;
    font-weight: 500;
    border-radius: var(--radius-md);
    border: 2px solid transparent;
    cursor: pointer;
    transition: all var(--transition-fast);
    text-decoration: none;
}

.btn-primary {
    background-color: var(--secondary-color);
    color: var(--primary-dark);
}

.btn-primary:hover {
    background-color: var(--secondary-light);
    color: var(--primary-dark);
}

.btn-outline {
    background-color: transparent;
    border-color: white;
    color: white;
}

.btn-outline:hover {
    background-color: white;
    color: var(--primary-color);
}

.btn-secondary {
    background-color: var(--primary-color);
    color: white;
}

.btn-secondary:hover {
    background-color: var(--primary-light);
    color: white;
}

.btn-sm {
    padding: var(--spacing-xs) var(--spacing-md);
    font-size: 0.875rem;
}

.btn-lg {
    padding: var(--spacing-md) var(--spacing-xl);
    font-size: 1rem;
}

/* ========================================
   Main Content
======================================== */
.main-content {
    padding: var(--spacing-3xl) 0;
}

.content-grid {
    display: grid;
    grid-template-columns: 1fr 320px;
    gap: var(--spacing-2xl);
}

.section-title {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: 1.5rem;
    margin-bottom: var(--spacing-lg);
    padding-bottom: var(--spacing-sm);
    border-bottom: 2px solid var(--primary-color);
}

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

/* ========================================
   Current Issue Section
======================================== */
.current-issue-card {
    display: flex;
    gap: var(--spacing-lg);
    background-color: var(--bg-light);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    margin-bottom: var(--spacing-xl);
}

.issue-cover {
    flex-shrink: 0;
    width: 150px;
}

.issue-cover img {
    width: 100%;
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-md);
}

.issue-cover-placeholder {
    width: 150px;
    height: 200px;
    background: linear-gradient(135deg, var(--primary-color), var(--primary-light));
    border-radius: var(--radius-md);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    color: white;
}

.volume-badge, .issue-badge {
    font-family: var(--font-serif);
    font-size: 0.875rem;
    font-weight: 600;
}

.issue-info h3 {
    font-size: 1.25rem;
    margin-bottom: var(--spacing-sm);
}

.issue-title {
    color: var(--text-light);
    margin-bottom: var(--spacing-sm);
}

.issue-date {
    color: var(--text-muted);
    font-size: 0.875rem;
    margin-bottom: var(--spacing-md);
}

/* ========================================
   Articles List
======================================== */
.articles-list {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-lg);
}

.article-card {
    padding: var(--spacing-lg);
    background-color: var(--bg-color);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    transition: box-shadow var(--transition-normal);
}

.article-card:hover {
    box-shadow: var(--shadow-md);
}

.article-type {
    display: inline-block;
    padding: var(--spacing-xs) var(--spacing-sm);
    background-color: var(--bg-accent);
    color: var(--primary-color);
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    border-radius: var(--radius-sm);
    margin-bottom: var(--spacing-sm);
}

.article-card h3 {
    font-size: 1.125rem;
    margin-bottom: var(--spacing-sm);
}

.article-card h3 a {
    color: var(--text-color);
}

.article-card h3 a:hover {
    color: var(--primary-color);
}

.article-authors {
    color: var(--text-light);
    font-size: 0.9375rem;
    margin-bottom: var(--spacing-sm);
}

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

.view-all-link {
    display: inline-block;
    margin-top: var(--spacing-lg);
    font-weight: 500;
}

/* ========================================
   Sidebar
======================================== */
.sidebar {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xl);
}

.sidebar-widget {
    background-color: var(--bg-light);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
}

.widget-title {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: 1.125rem;
    margin-bottom: var(--spacing-md);
    padding-bottom: var(--spacing-sm);
    border-bottom: 2px solid var(--primary-color);
}

.widget-title .icon {
    font-size: 1rem;
}

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

.announcements-list li {
    padding: var(--spacing-sm) 0;
    border-bottom: 1px solid var(--border-light);
}

.announcements-list li:last-child {
    border-bottom: none;
}

.ann-date {
    display: block;
    font-size: 0.75rem;
    color: var(--text-muted);
    margin-bottom: var(--spacing-xs);
}

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

.quick-links li {
    padding: var(--spacing-sm) 0;
    border-bottom: 1px solid var(--border-light);
}

.quick-links li:last-child {
    border-bottom: none;
}

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

.metrics-list li {
    display: flex;
    justify-content: space-between;
    padding: var(--spacing-sm) 0;
    border-bottom: 1px solid var(--border-light);
}

.metrics-list li:last-child {
    border-bottom: none;
}

.metric-label {
    color: var(--text-light);
    font-size: 0.875rem;
}

.metric-value {
    font-weight: 500;
}

.empty-state, .empty-text {
    color: var(--text-muted);
    font-style: italic;
}

/* ========================================
   Features Section
======================================== */
.features-section {
    background-color: var(--bg-light);
    padding: var(--spacing-3xl) 0;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--spacing-xl);
}

.feature-card {
    text-align: center;
    padding: var(--spacing-xl);
    background-color: var(--bg-color);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
}

.feature-icon {
    font-size: 2.5rem;
    margin-bottom: var(--spacing-md);
}

.feature-card h3 {
    font-size: 1.125rem;
    margin-bottom: var(--spacing-sm);
}

.feature-card p {
    color: var(--text-light);
    font-size: 0.9375rem;
    margin-bottom: 0;
}

/* ========================================
   Page Header
======================================== */
.page-header {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-dark) 100%);
    color: white;
    padding: var(--spacing-2xl) 0;
    text-align: center;
}

.page-header h1 {
    color: white;
    margin-bottom: var(--spacing-sm);
}

.page-header .breadcrumb {
    display: flex;
    justify-content: center;
    gap: var(--spacing-sm);
    font-size: 0.9375rem;
    opacity: 0.8;
}

.page-header .breadcrumb a {
    color: white;
}

/* ========================================
   Page Content
======================================== */
.page-content {
    padding: var(--spacing-3xl) 0;
}

.content-wrapper {
    max-width: 900px;
}

.content-wrapper.full-width {
    max-width: 100%;
}

/* ========================================
   Editorial Board
======================================== */
.board-section {
    margin-bottom: var(--spacing-3xl);
}

.board-section h2 {
    margin-bottom: var(--spacing-xl);
    padding-bottom: var(--spacing-sm);
    border-bottom: 2px solid var(--primary-color);
}

.board-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: var(--spacing-xl);
}

.board-member-card {
    background-color: var(--bg-light);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    text-align: center;
}

.member-photo {
    width: 120px;
    height: 120px;
    border-radius: 50%;
    overflow: hidden;
    margin: 0 auto var(--spacing-md);
    background-color: var(--primary-color);
    display: flex;
    align-items: center;
    justify-content: center;
}

.member-photo img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.member-photo .initials {
    color: white;
    font-family: var(--font-serif);
    font-size: 2rem;
    font-weight: 600;
}

.board-member-card h3 {
    font-size: 1.125rem;
    margin-bottom: var(--spacing-xs);
}

.member-title {
    color: var(--primary-color);
    font-weight: 500;
    font-size: 0.875rem;
    margin-bottom: var(--spacing-xs);
}

.member-affiliation {
    color: var(--text-light);
    font-size: 0.875rem;
    margin-bottom: var(--spacing-sm);
}

.member-email {
    font-size: 0.875rem;
}

/* ========================================
   Article Detail
======================================== */
.article-detail {
    background-color: var(--bg-color);
}

.article-header {
    margin-bottom: var(--spacing-xl);
}

.article-header .article-type {
    margin-bottom: var(--spacing-md);
}

.article-header h1 {
    font-size: 2rem;
    margin-bottom: var(--spacing-md);
}

.article-header .authors {
    font-size: 1.125rem;
    color: var(--text-light);
    margin-bottom: var(--spacing-md);
}

.article-info {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-lg);
    padding: var(--spacing-md);
    background-color: var(--bg-light);
    border-radius: var(--radius-md);
    font-size: 0.9375rem;
}

.article-info-item {
    display: flex;
    flex-direction: column;
}

.article-info-item .label {
    font-size: 0.75rem;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.article-info-item .value {
    font-weight: 500;
}

.article-section {
    margin-bottom: var(--spacing-xl);
}

.article-section h2 {
    font-size: 1.25rem;
    margin-bottom: var(--spacing-md);
    padding-bottom: var(--spacing-sm);
    border-bottom: 1px solid var(--border-color);
}

.keywords-list {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-sm);
}

.keyword-tag {
    display: inline-block;
    padding: var(--spacing-xs) var(--spacing-sm);
    background-color: var(--bg-accent);
    color: var(--primary-color);
    font-size: 0.875rem;
    border-radius: var(--radius-sm);
}

.download-section {
    padding: var(--spacing-lg);
    background-color: var(--bg-light);
    border-radius: var(--radius-lg);
    text-align: center;
}

/* ========================================
   Archives
======================================== */
.archives-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    gap: var(--spacing-xl);
}

.issue-card {
    background-color: var(--bg-light);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    text-align: center;
    transition: box-shadow var(--transition-normal);
}

.issue-card:hover {
    box-shadow: var(--shadow-md);
}

.issue-card .volume-info {
    font-family: var(--font-serif);
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--primary-color);
    margin-bottom: var(--spacing-sm);
}

.issue-card .issue-date {
    margin-bottom: var(--spacing-md);
}

/* ========================================
   Contact Form
======================================== */
.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-2xl);
}

.contact-form {
    background-color: var(--bg-light);
    padding: var(--spacing-xl);
    border-radius: var(--radius-lg);
}

.form-group {
    margin-bottom: var(--spacing-lg);
}

.form-group label {
    display: block;
    font-weight: 500;
    margin-bottom: var(--spacing-sm);
}

.form-group input,
.form-group textarea,
.form-group select {
    width: 100%;
    padding: var(--spacing-md);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    font-family: var(--font-sans);
    font-size: 1rem;
    transition: border-color var(--transition-fast);
}

.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
    outline: none;
    border-color: var(--primary-color);
}

.form-group textarea {
    min-height: 150px;
    resize: vertical;
}

.contact-info-card {
    padding: var(--spacing-lg);
    background-color: var(--bg-accent);
    border-radius: var(--radius-lg);
    margin-bottom: var(--spacing-lg);
}

.contact-info-card h3 {
    font-size: 1.125rem;
    margin-bottom: var(--spacing-md);
}

/* ========================================
   Footer
======================================== */
.main-footer {
    background-color: var(--primary-dark);
    color: white;
    padding: var(--spacing-3xl) 0 0;
}

.footer-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--spacing-xl);
    padding-bottom: var(--spacing-2xl);
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-section h4 {
    color: var(--secondary-color);
    font-size: 1.125rem;
    margin-bottom: var(--spacing-lg);
}

.footer-section p {
    color: rgba(255, 255, 255, 0.8);
    font-size: 0.9375rem;
}

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

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

.footer-links a {
    color: rgba(255, 255, 255, 0.8);
    font-size: 0.9375rem;
}

.footer-links a:hover {
    color: white;
}

.issn-info {
    margin-top: var(--spacing-md);
    font-size: 0.875rem;
}

.issn-info p {
    margin-bottom: var(--spacing-xs);
}

.footer-section address {
    font-style: normal;
    color: rgba(255, 255, 255, 0.8);
    font-size: 0.9375rem;
}

.footer-bottom {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--spacing-lg) 0;
    font-size: 0.875rem;
    color: rgba(255, 255, 255, 0.6);
}

.footer-bottom-links {
    display: flex;
    gap: var(--spacing-lg);
}

.footer-bottom-links a {
    color: rgba(255, 255, 255, 0.6);
}

.footer-bottom-links a:hover {
    color: white;
}

/* ========================================
   Alerts & Messages
======================================== */
.alert {
    padding: var(--spacing-md) var(--spacing-lg);
    border-radius: var(--radius-md);
    margin-bottom: var(--spacing-lg);
}

.alert-success {
    background-color: #d4edda;
    color: #155724;
    border: 1px solid #c3e6cb;
}

.alert-error {
    background-color: #f8d7da;
    color: #721c24;
    border: 1px solid #f5c6cb;
}

.alert-warning {
    background-color: #fff3cd;
    color: #856404;
    border: 1px solid #ffeeba;
}

.alert-info {
    background-color: #d1ecf1;
    color: #0c5460;
    border: 1px solid #bee5eb;
}

/* ========================================
   Responsive Design
======================================== */
@media (max-width: 992px) {
    .content-grid {
        grid-template-columns: 1fr;
    }
    
    .sidebar {
        display: grid;
        grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    }
    
    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .footer-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .contact-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    html {
        font-size: 15px;
    }
    
    .top-bar-content {
        flex-direction: column;
        gap: var(--spacing-sm);
    }
    
    .hero h1 {
        font-size: 2rem;
    }
    
    .hero-meta {
        flex-direction: column;
        gap: var(--spacing-sm);
    }
    
    .mobile-menu-toggle {
        display: flex;
    }
    
    .nav-menu {
        display: none;
        flex-direction: column;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background-color: var(--primary-color);
        box-shadow: var(--shadow-lg);
    }
    
    .nav-menu.active {
        display: flex;
    }
    
    .features-grid {
        grid-template-columns: 1fr;
    }
    
    .footer-grid {
        grid-template-columns: 1fr;
    }
    
    .footer-bottom {
        flex-direction: column;
        gap: var(--spacing-md);
        text-align: center;
    }
    
    .current-issue-card {
        flex-direction: column;
        align-items: center;
        text-align: center;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 var(--spacing-md);
    }
    
    .hero-buttons {
        flex-direction: column;
    }
    
    .btn {
        width: 100%;
    }
    
    .article-info {
        flex-direction: column;
    }
}