/**
 * JOAS - Journal of Open Aviation Science
 * Modern CSS Override for OJS 3.3.x
 * 
 * A clean, minimalistic stylesheet with modern serif typography
 * and a refined academic color palette based on TU Delft blue.
 */

/* ==========================================================================
   1. GOOGLE FONTS
   ========================================================================== */

@import url('https://fonts.googleapis.com/css2?family=Source+Serif+4:ital,opsz,wght@0,8..60,400;0,8..60,600;0,8..60,700;1,8..60,400&family=Inter:wght@400;500;600&display=swap');

/* ==========================================================================
   2. CSS CUSTOM PROPERTIES
   ========================================================================== */

:root {
    /* Primary Colors - Deep Navy & Slate Palette (avoiding TU Delft cyan) */
    --color-primary: #2c5282;
    /* Deep slate blue */
    --color-primary-dark: #1a365d;
    /* Darker navy for hover states */
    --color-primary-darker: #1a202c;
    /* Near-black navy for headings */
    --color-primary-light: #edf2f7;
    /* Light gray-blue tint for backgrounds */

    /* Accent Colors */
    --color-accent: #4a5568;
    /* Slate gray accent */
    --color-accent-warm: #c53030;
    /* Deep red accent for highlights */

    /* Neutral Colors */
    --color-white: #ffffff;
    --color-off-white: #fafbfc;
    --color-gray-50: #f8f9fa;
    --color-gray-100: #f1f3f5;
    --color-gray-200: #e9ecef;
    --color-gray-300: #dee2e6;
    --color-gray-400: #ced4da;
    --color-gray-500: #adb5bd;
    --color-gray-600: #6c757d;
    --color-gray-700: #495057;
    --color-gray-800: #343a40;
    --color-gray-900: #212529;

    /* Semantic Colors */
    --color-success: #38a169;
    --color-warning: #d69e2e;
    --color-error: #c53030;
    --color-info: #4a5568;

    /* Footer */
    --color-footer-bg: #edf2f7;
    --color-footer-text: #4a5568;

    /* Typography */
    --font-serif: 'Source Serif 4', Georgia, 'Times New Roman', serif;
    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;

    --font-size-xs: 0.75rem;
    /* 12px */
    --font-size-sm: 0.875rem;
    /* 14px */
    --font-size-base: 1rem;
    /* 16px */
    --font-size-lg: 1.125rem;
    /* 18px */
    --font-size-xl: 1.25rem;
    /* 20px */
    --font-size-2xl: 1.5rem;
    /* 24px */
    --font-size-3xl: 1.875rem;
    /* 30px */
    --font-size-4xl: 2.25rem;
    /* 36px */

    --line-height-tight: 1.2;
    --line-height-normal: 1.4;
    --line-height-relaxed: 1.5;

    /* Spacing */
    --space-1: 0.25rem;
    /* 4px */
    --space-2: 0.5rem;
    /* 8px */
    --space-3: 0.75rem;
    /* 12px */
    --space-4: 1rem;
    /* 16px */
    --space-5: 1.5rem;
    /* 24px */
    --space-6: 2rem;
    /* 32px */
    --space-8: 3rem;
    /* 48px */
    --space-10: 4rem;
    /* 64px */
    --space-12: 5rem;
    /* 80px */

    /* Layout */
    --max-width-content: 1100px;
    --max-width-article: 800px;
    --sidebar-width: 280px;

    /* Shadows */
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.08), 0 2px 4px -1px rgba(0, 0, 0, 0.04);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.08), 0 4px 6px -2px rgba(0, 0, 0, 0.04);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);

    /* Borders */
    --border-radius-sm: 4px;
    --border-radius-md: 6px;
    --border-radius-lg: 8px;
    --border-radius-xl: 12px;

    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-base: 250ms ease;
    --transition-slow: 350ms ease;
}

/* ==========================================================================
   3. BASE STYLES & RESETS
   ========================================================================== */

*,
*::before,
*::after {
    box-sizing: border-box;
}

html {
    font-size: 16px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-sans);
    font-size: var(--font-size-base);
    line-height: var(--line-height-normal);
    color: var(--color-gray-800);
    background-color: var(--color-white);
    margin: 0;
    padding: 0;
}

/* ==========================================================================
   4. TYPOGRAPHY
   ========================================================================== */

h1,
h2,
h3,
h4,
h5,
h6 {
    font-family: var(--font-serif);
    font-weight: 600;
    line-height: var(--line-height-tight);
    color: var(--color-primary-darker);
    margin-top: 0;
    margin-bottom: var(--space-4);
}

h1 {
    font-size: var(--font-size-4xl);
    font-weight: 700;
}

h2 {
    font-size: var(--font-size-3xl);
}

h3 {
    font-size: var(--font-size-2xl);
    margin-bottom: var(--space-4);
}

h4 {
    font-size: var(--font-size-xl);
}

h5 {
    font-size: var(--font-size-lg);
}

h6 {
    font-size: var(--font-size-base);
}

p {
    font-family: var(--font-serif);
    line-height: var(--line-height-tight);
    margin-top: 0;
    margin-bottom: var(--space-3);
}

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

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

ul,
ol {
    font-size: var(--font-size-base);
    padding-left: var(--space-5);
    margin-bottom: var(--space-4);
}

li {
    margin-bottom: var(--space-2);
}

strong,
b {
    font-weight: 600;
}

/* ==========================================================================
   5. OJS PAGE STRUCTURE
   ========================================================================== */

.pkp_structure_page {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.pkp_structure_content {
    flex: 1;
    background-color: var(--color-off-white);
    margin-top: 0 !important;
}

.pkp_page_index .pkp_structure_content {
    margin-top: 0;
    background-color: var(--color-off-white);
}

.pkp_structure_main {
    width: 100% !important;
    max-width: 100% !important;
    margin: 0 !important;
    padding: var(--space-2) var(--space-5) !important;
    border: none !important;
    background: transparent;
}

.pkp_structure_main::before,
.pkp_structure_main::after {
    display: none !important;
    background: none !important;
}

/* Hide sidebar - using full width layout */
.pkp_structure_sidebar {
    display: none !important;
}

@media (min-width: 992px) {
    .pkp_structure_main:first-child:last-child {
        float: none;
        margin-left: auto;
        margin-right: auto;
    }

    .pkp_structure_main {
        float: none;
        padding: var(--space-8) var(--space-6) var(--space-12);
    }
}

/* ==========================================================================
   6. HEADER & NAVIGATION
   ========================================================================== */

/* Remove background from wrapped containers */
div.pkp_all_wrapped,
div.pkp_all_wrapped * {
    background-color: transparent !important;
}

.pkp_structure_head {
    background-color: var(--color-primary) !important;
    border: none;
    box-shadow: var(--shadow-md);
    position: relative;
    z-index: 100;
}

.pkp_head_wrapper {
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 var(--space-5);
    background-color: transparent !important;
}

.pkp_site_name_wrapper {
    margin: 0 !important;
    padding: var(--space-3) 0;
    background-color: transparent !important;
}

.pkp_site_name .is_img {
    margin: 0 !important;
}

.pkp_site_name .is_img img {
    max-height: 30px;
    width: auto;
}

.pkp_site_name a {
    display: inline-flex;
    align-items: center;
}

/* Navigation */
nav.pkp_site_nav_menu,
div.pkp_head_wrapper nav.pkp_site_nav_menu,
header.pkp_structure_head div.pkp_head_wrapper nav.pkp_site_nav_menu,
header#headerNavigationContainer.pkp_structure_head div.pkp_head_wrapper nav.pkp_site_nav_menu {
    background-color: transparent !important;
    background: none !important;
}

.pkp_navigation_primary {
    background: transparent;
}

.pkp_nav_list {
    display: flex;
    list-style: none;
    margin: 0;
    padding: 0;
    margin-right: 100px !important;
}

.pkp_nav_list li {
    margin: 0;
}

.pkp_nav_list a {
    display: block;
    padding: var(--space-3) var(--space-4);
    color: var(--color-white);
    font-size: var(--font-size-sm);
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    transition: background-color var(--transition-fast), color var(--transition-fast);
    text-decoration: none;
}

.pkp_nav_list a:hover,
.pkp_nav_list .current a {
    background-color: rgba(255, 255, 255, 0.15);
    color: var(--color-white);
    text-decoration: none;
}

/* Dropdown Menu */
ul.dropdown-menu,
.dropdown-menu {
    background-color: var(--color-white) !important;
    border: 1px solid var(--color-gray-200);
    border-radius: var(--border-radius-md);
    box-shadow: var(--shadow-lg);
    padding: var(--space-2) 0;
    margin-top: var(--space-1);
    min-width: 180px;
    list-style: none;
    overflow: hidden;
}

.dropdown-menu li {
    margin: 0;
    padding: 0;
    overflow: hidden;
}

.dropdown-menu li a,
ul#navigationPrimary.pkp_navigation_primary.pkp_nav_list li ul.dropdown-menu li a {
    display: block;
    padding: var(--space-2) var(--space-4);
    margin: 0;
    color: var(--color-gray-900) !important;
    font-size: var(--font-size-sm);
    text-transform: none;
    letter-spacing: normal;
    background-color: transparent;
    width: 100%;
    box-sizing: border-box;
}

.dropdown-menu li a:hover,
ul#navigationPrimary.pkp_navigation_primary.pkp_nav_list li ul.dropdown-menu li a:hover {
    background-color: var(--color-gray-100) !important;
    color: var(--color-primary) !important;
}

.dropdown-menu .task_count {
    display: inline-block;
    background-color: var(--color-primary);
    color: var(--color-white);
    font-size: var(--font-size-xs);
    padding: 0 var(--space-2);
    border-radius: var(--border-radius-sm);
    margin-left: var(--space-2);
}

/* Search */
.pkp_navigation_search_wrapper {
    margin-right: 0;
}

.pkp_navigation_search_wrapper a {
    margin: 0;
    padding: var(--space-2) 0;
    color: var(--color-white);
}

.pkp_search {
    overflow: hidden;
}

.pkp_search input[type="text"] {
    font-family: var(--font-sans);
    font-size: var(--font-size-sm);
    padding: var(--space-2) var(--space-3);
    border: 2px solid transparent;
    border-radius: var(--border-radius-md);
    transition: border-color var(--transition-fast);
}

.pkp_search input[type="text"]:focus {
    outline: none;
    border-color: var(--color-primary);
}

/* ==========================================================================
   7. HOMEPAGE
   ========================================================================== */

/* Hero Image */
div.homepage_image {
    max-height: 320px;
    overflow: hidden;
    position: relative;
}

div.homepage_image img {
    height: inherit;
    object-fit: cover;
    object-position: 50% 50% !important;
    width: 100%;
}

/* About Section */
.pkp_page_index .homepage_about {
    padding-top: 0 !important;
}

.pkp_page_index .additional_content,
.additional_content {
    padding: var(--space-2) var(--space-5) !important;
    max-width: 100% !important;
    width: 100% !important;
    margin: 0 !important;
}

.pkp_page_index .additional_content>* {
    font-family: var(--font-serif) !important;
    font-size: var(--font-size-base) !important;
    font-weight: normal !important;
    line-height: var(--line-height-normal);
    color: var(--color-gray-900);
}

.pkp_page_index .additional_content h2,
.pkp_page_index .additional_content h3 {
    font-family: var(--font-serif) !important;
    font-weight: 600 !important;
    color: var(--color-primary-darker);
}

/* Current Issue on Homepage */
.current_issue {
    border-top: 1px solid var(--color-gray-200);
    margin-top: var(--space-8);
    padding: var(--space-6) var(--space-4);
    background-color: var(--color-white);
    border-radius: var(--border-radius-lg);
    box-shadow: var(--shadow-sm);
}

.current_issue * {
    font-family: var(--font-sans) !important;
}

.current_issue h2 {
    font-family: var(--font-serif) !important;
    color: var(--color-primary-darker);
    margin-bottom: var(--space-5);
}

/* ==========================================================================
   8. ARTICLES - LISTINGS & SUMMARIES
   ========================================================================== */

.obj_article_summary {
    padding: var(--space-5);
    margin-bottom: var(--space-4);
    background-color: var(--color-white);
    border-radius: var(--border-radius-md);
    border: 1px solid var(--color-gray-300);
    box-shadow: var(--shadow-md);
    transition: box-shadow var(--transition-base), transform var(--transition-base);
}

.obj_article_summary:hover {
    box-shadow: var(--shadow-lg);
    transform: translateY(-2px);
}

.obj_article_summary .title {
    font-family: var(--font-serif);
    font-size: var(--font-size-base);
    font-weight: 600;
    line-height: var(--line-height-tight);
    margin-bottom: var(--space-2);
}

.obj_article_summary .title a {
    color: var(--color-primary-darker);
    text-decoration: none;
}

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

.obj_article_summary .authors {
    font-size: var(--font-size-sm);
    color: var(--color-gray-600);
    margin-bottom: var(--space-3);
}

.obj_article_summary .meta {
    font-size: var(--font-size-sm);
    color: var(--color-gray-500);
}

/* Article list */
.cmp_article_list {
    list-style: none;
    padding: 0;
    margin: 0;
}

.cmp_article_list>li {
    margin-bottom: var(--space-4) !important;
}

/* Galley Links (PDF, HTML badges) */
.galleys_links {
    display: flex;
    gap: var(--space-2);
    flex-wrap: wrap;
    margin: var(--space-3) 0 0 0;
}

.obj_galley_link {
    display: inline-flex;
    align-items: center;
    padding: var(--space-1) var(--space-3);
    font-size: var(--font-size-xs);
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    color: var(--color-white);
    background-color: var(--color-primary);
    border-radius: var(--border-radius-sm);
    text-decoration: none;
    transition: background-color var(--transition-fast), transform var(--transition-fast);
}

.obj_galley_link:hover {
    background-color: var(--color-primary-dark);
    color: var(--color-white);
    text-decoration: none;
    transform: translateY(-1px);
}

/* PDF badge - slightly different color */
.obj_galley_link.pdf {
    background-color: var(--color-accent-warm);
}

.obj_galley_link.pdf:hover {
    background-color: #b84700;
}

/* ==========================================================================
   9. ARTICLE DETAIL PAGE
   ========================================================================== */

.obj_article_details {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-6);
    max-width: 100%;
    overflow: hidden;
}

.obj_article_details > .row {
    margin-left: 0;
    margin-right: 0;
    width: 100%;
}

.obj_article_details .main_entry {
    flex: 1;
    min-width: 0;
    width: 65% !important;
    font-family: var(--font-sans) !important;
    font-weight: normal;
}

.obj_article_details .main_entry .page_title {
    font-family: var(--font-serif);
    font-size: var(--font-size-3xl);
    color: var(--color-primary-darker);
    margin-bottom: var(--space-4);
}

.obj_article_details .main_entry .authors {
    font-size: var(--font-size-lg);
    color: var(--color-gray-900);
    margin-bottom: var(--space-5);
}

.obj_article_details .main_entry .item {
    margin-bottom: var(--space-6);
}

.obj_article_details .main_entry .item h2,
.obj_article_details .main_entry .item h3 {
    font-family: var(--font-serif);
    font-size: var(--font-size-xl);
    color: var(--color-primary-darker);
    margin-bottom: var(--space-3);
    padding-bottom: var(--space-2);
    border-bottom: 2px solid var(--color-primary-light);
}

.obj_article_details .main_entry .item.abstract p {
    font-size: var(--font-size-base);
    line-height: var(--line-height-normal);
    color: var(--color-gray-900);
}

/* Entry Details Sidebar */
.obj_article_details .entry_details {
    width: 30% !important;
    min-width: 280px;
    padding-top: 0 !important;
    padding-bottom: 0 !important;
    margin-top: 0 !important;
    margin-bottom: 0 !important;
    font-family: var(--font-sans) !important;
    font-size: var(--font-size-xs) !important;
}

.obj_article_details .entry_details * {
    font-family: var(--font-sans) !important;
    font-size: var(--font-size-xs) !important;
    margin-top: 0 !important;
    margin-bottom: 0 !important;
    padding-top: 0 !important;
    padding-bottom: 0 !important;
}

.obj_article_details .entry_details .item.cover_image {
    margin-bottom: var(--space-2) !important;
    padding: var(--space-2) !important;
    text-align: center;
}

.obj_article_details .entry_details .item.cover_image img {
    max-height: 200px;
    width: auto;
    max-width: 100%;
    margin: 0 auto;
    display: block;
}

.obj_article_details .entry_details .item {
    margin-bottom: var(--space-2) !important;
    padding: var(--space-2) var(--space-3) var(--space-3) var(--space-3) !important;
    background-color: var(--color-white);
    border-radius: var(--border-radius-md);
    box-shadow: var(--shadow-sm);
}

.obj_article_details .entry_details .item.addthis {
    display: none;
}

.obj_article_details .entry_details .label,
.obj_article_details .entry_details h2 {
    font-weight: 600;
    color: var(--color-primary-darker);
    margin-bottom: var(--space-1) !important;
    font-size: var(--font-size-xs) !important;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    background: none !important;
}

.obj_article_details .entry_details .sub_item .label {
    margin-top: 0 !important;
    background: none !important;
}

.obj_article_details .entry_details .value {
    color: var(--color-gray-900);
}

.obj_article_details .entry_details section {
    margin-top: 0 !important;
    margin-bottom: 0 !important;
}

.obj_article_details .entry_details ul {
    list-style: none;
    margin-top: 0 !important;
    margin-bottom: 0 !important;
    padding-left: 0 !important;
}

.obj_article_details .entry_details li {
    margin-bottom: var(--space-1) !important;
}

.obj_article_details .entry_details p {
    margin-bottom: var(--space-1) !important;
}

.obj_article_details .entry_details .item.copyright p {
    line-height: 1.3 !important;
}

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

/* DOI styling */
.obj_article_details .entry_details .item.doi .value a {
    word-break: break-all;
    color: var(--color-primary);
}

/* Keywords */
.obj_article_details .entry_details .item.keywords .value {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-1);
}

/* Item galleys in detail page */
.item.galleys {
    border: none !important;
}

/* ==========================================================================
   10. ISSUES & ARCHIVE
   ========================================================================== */

.obj_issue_toc {
    background-color: var(--color-white);
    border-radius: var(--border-radius-lg);
    box-shadow: var(--shadow-sm);
    padding: var(--space-6);
    margin-bottom: var(--space-6);
}

.obj_issue_toc .cover {
    max-width: 20% !important;
    border-radius: var(--border-radius-md);
    overflow: hidden;
    box-shadow: var(--shadow-md);
}

.obj_issue_toc .cover img {
    display: block;
    width: 100%;
    height: auto;
}

.obj_issue_toc .galleys,
.obj_issue_toc .section {
    padding: var(--space-3);
}

.obj_issue_toc .galleys::before,
.obj_issue_toc .section::before {
    border-top: none;
}

.obj_issue_toc .galleys_links,
.obj_article_summary .galleys_links {
    margin: 0;
}

/* Issue summary in archive */
.obj_issue_summary {
    padding: var(--space-5);
    margin-bottom: var(--space-4);
    background-color: var(--color-white);
    border-radius: var(--border-radius-md);
    border: 1px solid var(--color-gray-300);
    box-shadow: var(--shadow-md);
    transition: box-shadow var(--transition-base);
}

.obj_issue_summary:hover {
    box-shadow: var(--shadow-lg);
}

.obj_issue_summary .title {
    font-family: var(--font-serif);
    font-size: var(--font-size-xl);
    color: var(--color-primary-darker);
}

.issues_archive {
    display: grid;
    gap: var(--space-4);
}

/* Sections in TOC */
.sections {
    margin-top: var(--space-4) !important;
}

.sections .section {
    margin-bottom: var(--space-5);
}

.sections .section h2 {
    font-family: var(--font-serif);
    font-size: var(--font-size-2xl);
    color: var(--color-primary-darker);
    padding: var(--space-4) 0 var(--space-2) 0 !important;
    margin-bottom: var(--space-4);
    background: none !important;
    left: 0 !important;
    border-bottom: 2px solid var(--color-primary-light);
}

.sections .section h3 {
    font-family: var(--font-serif);
    font-size: var(--font-size-lg);
    background: none !important;
    padding-top: var(--space-3);
    color: var(--color-gray-900);
}

/* ==========================================================================
   11. BOOTSTRAP-COMPATIBLE GRID SYSTEM
   ========================================================================== */

.row {
    display: flex;
    flex-wrap: wrap;
    margin-top: calc(-1 * var(--space-4));
    margin-left: calc(-0.5 * var(--space-4));
    margin-right: calc(-0.5 * var(--space-4));
}

.row>* {
    box-sizing: border-box;
    flex-shrink: 0;
    width: 100%;
    max-width: 100%;
    padding-left: calc(var(--space-4) * 0.5);
    padding-right: calc(var(--space-4) * 0.5);
    margin-top: var(--space-4);
}

.col {
    flex: 1 0 0%;
}

/* Row cols utilities */
.row-cols-1>* {
    flex: 0 0 auto;
    width: 100%;
}

.row-cols-2>* {
    flex: 0 0 auto;
    width: 50%;
}

.row-cols-3>* {
    flex: 0 0 auto;
    width: 33.333333%;
}

.row-cols-4>* {
    flex: 0 0 auto;
    width: 25%;
}

@media (min-width: 768px) {
    .row-cols-md-2>* {
        flex: 0 0 auto;
        width: 50%;
    }

    .row-cols-md-3>* {
        flex: 0 0 auto;
        width: 33.333333%;
    }

    .row-cols-md-4>* {
        flex: 0 0 auto;
        width: 25%;
    }
}

@media (min-width: 992px) {
    .row-cols-lg-2>* {
        flex: 0 0 auto;
        width: 50%;
    }

    .row-cols-lg-3>* {
        flex: 0 0 auto;
        width: 33.333333%;
    }

    .row-cols-lg-4>* {
        flex: 0 0 auto;
        width: 25%;
    }
}

/* Gap utilities - override row gutters */
.g-1 {
    margin-left: calc(-0.5 * var(--space-1));
    margin-right: calc(-0.5 * var(--space-1));
    margin-top: calc(-1 * var(--space-1));
}

.g-1>* {
    padding-left: calc(var(--space-1) * 0.5);
    padding-right: calc(var(--space-1) * 0.5);
    margin-top: var(--space-1);
}

.g-2 {
    margin-left: calc(-0.5 * var(--space-2));
    margin-right: calc(-0.5 * var(--space-2));
    margin-top: calc(-1 * var(--space-2));
}

.g-2>* {
    padding-left: calc(var(--space-2) * 0.5);
    padding-right: calc(var(--space-2) * 0.5);
    margin-top: var(--space-2);
}

.g-3 {
    margin-left: calc(-0.5 * var(--space-3));
    margin-right: calc(-0.5 * var(--space-3));
    margin-top: calc(-1 * var(--space-3));
}

.g-3>* {
    padding-left: calc(var(--space-3) * 0.5);
    padding-right: calc(var(--space-3) * 0.5);
    margin-top: var(--space-3);
}

.g-4 {
    margin-left: calc(-0.5 * var(--space-4));
    margin-right: calc(-0.5 * var(--space-4));
    margin-top: calc(-1 * var(--space-4));
}

.g-4>* {
    padding-left: calc(var(--space-4) * 0.5);
    padding-right: calc(var(--space-4) * 0.5);
    margin-top: var(--space-4);
}

.g-5 {
    margin-left: calc(-0.5 * var(--space-5));
    margin-right: calc(-0.5 * var(--space-5));
    margin-top: calc(-1 * var(--space-5));
}

.g-5>* {
    padding-left: calc(var(--space-5) * 0.5);
    padding-right: calc(var(--space-5) * 0.5);
    margin-top: var(--space-5);
}

/* Margin utilities */
.mb-1 {
    margin-bottom: var(--space-1);
}

.mb-2 {
    margin-bottom: var(--space-2);
}

.mb-3 {
    margin-bottom: var(--space-3);
}

.mb-4 {
    margin-bottom: var(--space-4);
}

.mb-5 {
    margin-bottom: var(--space-5);
}

/* ==========================================================================
   12. CARDS & COMPONENTS
   ========================================================================== */

.card {
    display: flex;
    flex-direction: column;
    background-color: var(--color-white);
    border: 1px solid var(--color-gray-300);
    border-radius: var(--border-radius-lg);
    overflow: hidden;
    transition: box-shadow var(--transition-base), transform var(--transition-base);
}

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

.card.h-100 {
    height: 100%;
}

.card.border-secondary {
    border-color: var(--color-gray-400);
}

.card-header {
    background-color: var(--color-gray-100);
    border-bottom: 1px solid var(--color-gray-200);
    padding: var(--space-3) var(--space-3);
    font-family: var(--font-sans);
    font-weight: 600;
    font-size: var(--font-size-sm);
    color: var(--color-primary-darker);
}

.card-header em,
.card-header i {
    margin: 0;
    color: var(--color-primary);
}

.card-body {
    flex: 1;
    padding: var(--space-4);
}

.card-text {
    font-family: var(--font-serif);
    font-size: var(--font-size-sm);
    line-height: var(--line-height-normal);
    color: var(--color-gray-900);
    margin-bottom: 0;
}

.card-footer {
    background-color: var(--color-gray-50);
    border-top: 1px solid var(--color-gray-200);
    padding: var(--space-3) var(--space-4);
}

.card-header h3,
.card-header h4 {
    font-family: var(--font-serif);
    color: var(--color-primary-darker);
    margin: 0;
}

/* ==========================================================================
   13. BUTTONS
   ========================================================================== */

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-family: var(--font-sans);
    font-size: var(--font-size-sm);
    font-weight: 500;
    padding: var(--space-2) var(--space-4);
    border: 1px solid var(--color-gray-400);
    border-radius: var(--border-radius-md);
    background-color: var(--color-gray-100);
    color: var(--color-gray-900);
    cursor: pointer;
    text-decoration: none;
    transition: all var(--transition-fast);
}

.btn:hover {
    background-color: var(--color-gray-200);
    border-color: var(--color-gray-500);
    text-decoration: none;
}

.btn-sm {
    font-size: var(--font-size-xs);
    padding: var(--space-1) var(--space-3);
}

.btn-lg {
    font-size: var(--font-size-base);
    padding: var(--space-3) var(--space-5);
}

/* Primary button */
.btn-primary {
    background-color: var(--color-primary);
    border-color: var(--color-primary);
    color: var(--color-white);
}

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

/* Secondary button */
.btn-secondary {
    background-color: var(--color-gray-600);
    border-color: var(--color-gray-600);
    color: var(--color-white);
}

.btn-secondary:hover {
    background-color: var(--color-gray-900);
    border-color: var(--color-gray-900);
    color: var(--color-white);
}

/* Outline buttons */
.btn-outline-primary {
    background-color: transparent;
    border-color: var(--color-primary);
    color: var(--color-primary);
}

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

.btn-outline-secondary {
    background-color: transparent;
    border-color: var(--color-gray-500);
    color: var(--color-gray-600);
}

.btn-outline-secondary:hover {
    background-color: var(--color-gray-600);
    border-color: var(--color-gray-600);
    color: var(--color-white);
}

/* Success, Warning, Danger buttons */
.btn-success {
    background-color: var(--color-success);
    border-color: var(--color-success);
    color: var(--color-white);
}

.btn-success:hover {
    background-color: #2f855a;
    border-color: #2f855a;
    color: var(--color-white);
}

.btn-warning {
    background-color: var(--color-warning);
    border-color: var(--color-warning);
    color: var(--color-gray-900);
}

.btn-warning:hover {
    background-color: #b7791f;
    border-color: #b7791f;
    color: var(--color-white);
}

.btn-danger {
    background-color: var(--color-error);
    border-color: var(--color-error);
    color: var(--color-white);
}

.btn-danger:hover {
    background-color: #9b2c2c;
    border-color: #9b2c2c;
    color: var(--color-white);
}

/* Breadcrumbs */
.cmp_breadcrumbs {
    font-family: var(--font-sans);
    font-size: var(--font-size-sm);
    color: var(--color-gray-600);
    padding: var(--space-4) 0;
}

.cmp_breadcrumbs ol {
    margin-bottom: 0;
}

.cmp_breadcrumbs a {
    color: var(--color-primary);
}

.cmp_breadcrumbs .separator {
    margin: 0 var(--space-2);
    color: var(--color-gray-400);
}

/* Notifications */
.cmp_notification {
    font-size: var(--font-size-base) !important;
    padding: var(--space-4) var(--space-5);
    border-radius: var(--border-radius-md);
    margin-bottom: var(--space-4);
}

.page_submissions .cmp_notification {
    border: 2px solid var(--color-warning);
    background: #fffbeb;
    margin: var(--space-5) auto var(--space-8);
    font-size: var(--font-size-lg) !important;
}

.page_submissions .cmp_notification a {
    font-weight: 600;
    margin: 0 var(--space-2);
    color: var(--color-primary);
}

/* Submission page policies */
.page_submissions .section_policy {
    border: 1px solid var(--color-gray-200);
    border-radius: var(--border-radius-md);
    padding: var(--space-4);
    margin: var(--space-4) auto;
    background-color: var(--color-white);
}

.page_submissions .submission_checklist li {
    padding: var(--space-3) var(--space-5) var(--space-3) var(--space-8);
}

/* ==========================================================================
   12. FOOTER
   ========================================================================== */

.pkp_structure_footer_wrapper {
    background-color: var(--color-primary) !important;
    border-top: none;
    margin-top: auto;
}

.pkp_footer_content {
    max-width: 1400px;
    margin: 0 auto;
    padding: var(--space-8) var(--space-5);
    color: var(--color-white);
}

.pkp_footer_content table {
    width: 100%;
}

.pkp_footer_content a {
    color: rgba(255, 255, 255, 0.85);
}

.pkp_footer_content a:hover {
    color: var(--color-white);
}

.pkp_brand_footer {
    padding: var(--space-4) 0;
    border-top: 1px solid var(--color-gray-300);
    text-align: center;
}

.pkp_brand_footer img {
    height: 50px;
    opacity: 0.8;
    transition: opacity var(--transition-fast);
}

.pkp_brand_footer img:hover {
    opacity: 1;
}

/* ==========================================================================
   13. EDITORS PAGE
   ========================================================================== */

.editors {
    margin: 0 var(--space-4);
}

.editors .editor {
    margin-bottom: var(--space-4);
    padding: var(--space-4);
    background-color: var(--color-white);
    border-radius: var(--border-radius-md);
    border: 1px solid var(--color-gray-300);
    box-shadow: var(--shadow-md);
    transition: box-shadow var(--transition-base);
}

.editors .editor:hover {
    box-shadow: var(--shadow-lg);
}

.editors .editor::before {
    content: none;
}

.editors .editor .continue::after {
    content: ", ";
}

.editors .editor .name {
    font-family: var(--font-serif);
    font-weight: 600;
    font-size: var(--font-size-lg);
    color: var(--color-primary-darker);
    display: block;
    margin-bottom: var(--space-2);
}

.editors .editor .affiliation {
    font-size: var(--font-size-sm);
    color: var(--color-gray-600);
    margin-bottom: var(--space-2);
}

.editors .editor .bio {
    padding: var(--space-4);
    background-color: var(--color-gray-50);
    border-radius: var(--border-radius-sm);
    margin: var(--space-3) 0;
    font-size: var(--font-size-sm);
    line-height: var(--line-height-normal);
    color: var(--color-gray-900);
}

.editors .editor input {
    display: none;
}

.editors .editor label {
    display: inline-block;
    padding: var(--space-1) var(--space-3);
    font-size: var(--font-size-xs);
    font-weight: 500;
    color: var(--color-primary);
    background-color: var(--color-primary-light);
    border: 1px solid var(--color-primary);
    border-radius: var(--border-radius-sm);
    cursor: pointer;
    transition: all var(--transition-fast);
}

.editors .editor label:hover {
    background-color: var(--color-primary);
    color: var(--color-white);
}

.editors .editor input:checked+label+div {
    display: none;
}

.editors .editor input+label::before {
    content: "hide ";
}

.editors .editor input:checked+label::before {
    content: "show ";
}

/* ==========================================================================
   14. BUTTONS & FORMS
   ========================================================================== */

button,
.btn,
input[type="submit"],
input[type="button"] {
    font-family: var(--font-sans);
    font-size: var(--font-size-sm);
    font-weight: 500;
    padding: var(--space-2) var(--space-4);
    border: none;
    border-radius: var(--border-radius-md);
    cursor: pointer;
    transition: all var(--transition-fast);
}

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

.btn-primary:hover,
.pkp_button:hover {
    background-color: var(--color-primary-dark);
    color: var(--color-white);
}

.btn-secondary {
    background-color: var(--color-gray-200);
    color: var(--color-gray-900);
}

.btn-secondary:hover {
    background-color: var(--color-gray-300);
}

/* Form inputs */
input[type="text"],
input[type="email"],
input[type="password"],
input[type="url"],
input[type="search"],
textarea,
select {
    font-family: var(--font-sans);
    font-size: var(--font-size-base);
    padding: var(--space-3) var(--space-4);
    border: 1px solid var(--color-gray-300);
    border-radius: var(--border-radius-md);
    background-color: var(--color-white);
    transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
    width: 100%;
}

input[type="text"]:focus,
input[type="email"]:focus,
input[type="password"]:focus,
input[type="url"]:focus,
input[type="search"]:focus,
textarea:focus,
select:focus {
    outline: none;
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px rgba(0, 115, 168, 0.15);
}

label {
    display: block;
    font-weight: 500;
    margin-bottom: var(--space-2);
    color: var(--color-gray-900);
}

/* ==========================================================================
   15. HEADINGS OVERRIDE (OJS Specifics)
   ========================================================================== */

.pkp_structure_main h1,
.pkp_structure_main h2,
.pkp_structure_main h3,
.pkp_structure_main h4 {
    font-family: var(--font-serif) !important;
    color: var(--color-primary-darker);
}

.main_entry {
    font-family: var(--font-sans) !important;
    font-weight: normal;
}

/* ==========================================================================
   16. RESPONSIVE DESIGN
   ========================================================================== */

@media (max-width: 991px) {
    :root {
        --font-size-4xl: 1.875rem;
        --font-size-3xl: 1.5rem;
        --font-size-2xl: 1.25rem;
    }

    .pkp_structure_main {
        padding: var(--space-5) var(--space-4) var(--space-8);
    }

    .obj_article_details {
        flex-direction: column;
    }

    .obj_article_details .main_entry {
        width: 100% !important;
    }

    .obj_article_details .entry_details {
        width: 100% !important;
        display: grid;
        grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
        gap: var(--space-4);
    }

    .pkp_nav_list {
        margin-right: 0 !important;
    }

    .homepage_image {
        max-height: 200px;
    }
}

@media (max-width: 767px) {
    .pkp_structure_main {
        padding: var(--space-4) var(--space-3) var(--space-6);
    }

    .pkp_head_wrapper {
        padding: 0 var(--space-3);
    }

    .pkp_nav_list a {
        padding: var(--space-2) var(--space-3);
        font-size: var(--font-size-xs);
    }

    .obj_article_details .entry_details {
        grid-template-columns: 1fr;
    }

    .obj_issue_toc .cover {
        max-width: 40% !important;
    }

    .editors .editor {
        padding: var(--space-3);
    }

    .current_issue {
        padding: var(--space-4) var(--space-3);
    }
}

@media (max-width: 479px) {
    .pkp_nav_list {
        flex-wrap: wrap;
        justify-content: center;
    }

    .galleys_links {
        flex-direction: column;
    }

    .obj_galley_link {
        text-align: center;
        justify-content: center;
    }

    .obj_issue_toc .cover {
        max-width: 60% !important;
        margin: 0 auto var(--space-4);
    }
}

/* ==========================================================================
   17. PRINT STYLES
   ========================================================================== */

@media print {

    .pkp_structure_head,
    .pkp_structure_footer_wrapper,
    .pkp_navigation_search_wrapper,
    .galleys_links,
    .editors .editor label {
        display: none !important;
    }

    .pkp_structure_main {
        width: 100% !important;
        max-width: none;
        padding: 0;
    }

    .obj_article_details .main_entry,
    .obj_article_details .entry_details {
        width: 100% !important;
    }

    body {
        font-size: 12pt;
        line-height: 1.5;
        color: #000;
    }

    a {
        color: #000;
        text-decoration: underline;
    }

    h1,
    h2,
    h3,
    h4,
    h5,
    h6 {
        color: #000;
        page-break-after: avoid;
    }
}

/* ==========================================================================
   18. UTILITY CLASSES
   ========================================================================== */

.visually-hidden {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

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

.text-muted {
    color: var(--color-gray-600);
}

.mb-0 {
    margin-bottom: 0;
}

.mt-0 {
    margin-top: 0;
}