/* =============================================================================
   ASLAM VILLAN - RESEARCH SCIENTIST WEBSITE
   Modern, Pixel-Perfect Design with Two-Column Layout
   ============================================================================= */

/* CSS Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

/* Root Variables for Consistent Design System */
:root {
    /* Color Palette */
    --primary-blue: #2563eb;
    --primary-blue-hover: #1d4ed8;
    --primary-blue-light: #dbeafe;
    --text-primary: #1f2937;
    --text-secondary: #6b7280;
    --text-light: #9ca3af;
    --background-white: #ffffff;
    --background-gray: #f9fafb;
    --border-light: #e5e7eb;
    --separator-color: #d1d5db;
    
    /* Typography */
    --font-family: 'Source Sans Pro', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --font-size-xs: 0.75rem;
    --font-size-sm: 0.875rem;
    --font-size-base: 1rem;
    --font-size-lg: 1.125rem;
    --font-size-xl: 1.25rem;
    --font-size-2xl: 1.5rem;
    --font-size-3xl: 1.875rem;
    --font-size-4xl: 2.25rem;
    
    /* Spacing System */
    --spacing-1: 0.25rem;
    --spacing-2: 0.5rem;
    --spacing-3: 0.75rem;
    --spacing-4: 1rem;
    --spacing-5: 1.25rem;
    --spacing-6: 1.5rem;
    --spacing-8: 2rem;
    --spacing-10: 2.5rem;
    --spacing-12: 3rem;
    --spacing-16: 4rem;
    --spacing-20: 5rem;
    --spacing-24: 6rem;
    --spacing-28: 7rem;
    --spacing-32: 8rem;
    
    /* Layout Dimensions */
    --sidebar-width: 400px;
    --separator-width: 1px;
    --content-max-width: 800px;
    
    /* Unified Top Offset for Right Content Sections */
    --content-top-offset: 8rem; /* controls how low the right content starts */
    
    /* Border Radius */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    
    /* 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), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
    
    /* Transitions */
    --transition-fast: 150ms ease-in-out;
    --transition-normal: 250ms ease-in-out;
    --transition-slow: 350ms ease-in-out;
}

/* Base Typography */
body {
    font-family: var(--font-family);
    font-size: var(--font-size-base);
    line-height: 1.6;
    color: var(--text-primary);
    background-color: var(--background-white);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* =============================================================================
   MAIN LAYOUT CONTAINER
   ============================================================================= */

.container {
    display: flex;
    min-height: 100vh;
    position: relative;
    max-width: 1200px;
    margin: 0 auto;
    width: 100%;
}

/* =============================================================================
   LEFT SIDEBAR - Fixed Navigation & Profile
   ============================================================================= */

.sidebar {
    width: var(--sidebar-width);
    background-color: var(--background-white);
    padding: var(--spacing-8) var(--spacing-12);
    position: relative;
    height: 100vh;
    overflow-y: auto;
    z-index: 100;
    display: flex;
    flex-direction: column;
}

/* Profile Section */
.profile {
    padding-left: var(--spacing-12);
    margin-top: var(--spacing-12);
}

/* Social Icons */
.social-icons {
    display: flex;
    justify-content: center;
    gap: var(--spacing-4);
    padding: var(--spacing-4) 0;
    margin-top: var(--spacing-8);
}

.social-icon-link {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background-color: var(--background-gray);
    border-radius: 50%;
    text-decoration: none;
    transition: all var(--transition-fast);
}

.social-icon-link:hover {
    background-color: var(--primary-blue);
    transform: translateY(-2px);
    box-shadow: var(--shadow-sm);
}

.social-icon-link .social-icon {
    font-size: var(--font-size-lg);
    color: var(--text-secondary);
    transition: color var(--transition-fast);
}

.social-icon-link:hover .social-icon {
    color: white;
}

.name {
    font-size: var(--font-size-2xl);
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: var(--spacing-2);
    line-height: 1.2;
    letter-spacing: 0.06em;
}

.title {
    font-size: var(--font-size-base);
    font-weight: 400;
    color: var(--text-light);
    line-height: 1.4;
}

/* Navigation Menu */
.navigation {
    margin-top: var(--spacing-12);
    padding-left: var(--spacing-12);
}

.nav-list {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-1);
}

.nav-item {
    width: 100%;
}

.nav-link {
    display: flex;
    align-items: center;
    padding: var(--spacing-4) var(--spacing-6);
    color: var(--text-primary);
    text-decoration: none;
    font-size: var(--font-size-base);
    font-weight: 500;
    border-radius: var(--radius-lg);
    transition: all var(--transition-fast);
    position: relative;
    gap: var(--spacing-3);
}

.nav-icon {
    font-size: var(--font-size-lg);
    width: 24px;
    text-align: center;
    margin-top: 3px;
}

.nav-text {
    font-weight: 500;
}

.nav-link:hover {
    background-color: var(--background-gray);
    color: var(--primary-blue);
    transform: translateX(2px);
}

.nav-link.active {
    color: var(--primary-blue);
    font-weight: 600;
}

.nav-link.active .nav-icon img {
    filter: brightness(0) saturate(100%) invert(27%) sepia(96%) saturate(7500%) hue-rotate(214deg) brightness(95%) contrast(101%);
}

.nav-link.active::before {
    content: '';
    position: absolute;
    left: -16px;
    top: 50%;
    transform: translateY(-50%);
    width: 3px;
    height: 20px;
    background-color: var(--primary-blue);
    border-radius: var(--radius-sm);
}

/* =============================================================================
   VERTICAL SEPARATOR - REMOVED
   ============================================================================= */

/* =============================================================================
   RIGHT CONTENT AREA - Scrollable Main Content
   ============================================================================= */

.content-area {
    flex: 1;
    padding: var(--spacing-8) var(--spacing-12) var(--spacing-8) var(--spacing-12);
    max-width: var(--content-max-width);
    height: 100vh;
    overflow: hidden;
}

/* Content Sections */
.content-section {
    opacity: 1;
    transform: translateY(0);
    transition: all var(--transition-normal);
}

.content-section.hidden {
    opacity: 0;
    transform: translateY(20px);
    pointer-events: none;
    position: absolute;
    width: 100%;
}

.section-title {
    font-size: var(--font-size-2xl);
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-8);
    margin-top: var(--spacing-16);
    padding-bottom: var(--spacing-3);
    border-bottom: 2px solid var(--border-light);
}

/* =============================================================================
   LANDING PAGE STYLES
   ============================================================================= */

.landing-container {
    height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: flex-start;
    overflow: hidden;
}

.landing-content {
    display: flex;
    align-items: center;
    justify-content: center;
    height: 100%;
}

.welcome-text {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-6);
}

.welcome-title {
    font-size: var(--font-size-4xl);
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: var(--spacing-2);
    background: linear-gradient(135deg, var(--primary-blue), #1e40af);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.welcome-subtitle {
    font-size: var(--font-size-xl);
    font-weight: 500;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-4);
}

.landing-description {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-4);
}

.landing-description p {
    font-size: var(--font-size-lg);
    color: var(--text-secondary);
    line-height: 1.7;
}

.landing-cta {
    display: flex;
    gap: var(--spacing-4);
    margin-top: var(--spacing-6);
}

.cta-button {
    padding: var(--spacing-4) var(--spacing-6);
    border-radius: var(--radius-lg);
    text-decoration: none;
    font-weight: 600;
    font-size: var(--font-size-base);
    transition: all var(--transition-normal);
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-2);
}

.cta-button.primary {
    background: linear-gradient(135deg, var(--primary-blue), #1e40af);
    color: white;
    box-shadow: var(--shadow-md);
}

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

.cta-button.secondary {
    background-color: var(--background-gray);
    color: var(--primary-blue);
    border: 2px solid var(--primary-blue-light);
}

.cta-button.secondary:hover {
    background-color: var(--primary-blue-light);
    transform: translateY(-1px);
}

/* Profile Photo Styles */
.profile-photo {
    display: flex;
    justify-content: center;
    align-items: center;
    margin-top:175px;
}

.photo-container {
    position: relative;
    width: 250px;
    height: 250px;
    border-radius: 50%;
    overflow: hidden;
    box-shadow: var(--shadow-lg);
    transition: transform var(--transition-normal);
}

.photo-container:hover {
    transform: scale(1.02);
}

.profile-img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform var(--transition-normal);
}

.home-social-icons {
    display: flex;
    justify-content: center;
    gap: var(--spacing-4);
    margin-top: var(--spacing-6);
}

.home-social-icons a {
    display: flex;
    align-items: center;
    justify-content: center;
    transition: opacity var(--transition-fast);
    text-decoration: none;
}

.home-social-icons a:hover {
    opacity: 0.7;
}

.photo-overlay {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    background: linear-gradient(transparent, rgba(0,0,0,0.7));
    padding: var(--spacing-6);
    display: flex;
    align-items: flex-end;
}

.photo-badge {
    background-color: var(--primary-blue);
    color: white;
    padding: var(--spacing-2) var(--spacing-4);
    border-radius: var(--radius-md);
    font-size: var(--font-size-sm);
    font-weight: 600;
}

/* Quick Stats Section */
.quick-stats {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--spacing-6);
    margin-top: var(--spacing-16);
    padding: var(--spacing-8);
    background: linear-gradient(135deg, var(--background-gray), #f8fafc);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-light);
}

.stat-item {
    text-align: center;
    padding: var(--spacing-4);
    background-color: white;
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-sm);
    transition: transform var(--transition-normal);
}

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

.stat-number {
    font-size: var(--font-size-3xl);
    font-weight: 700;
    color: var(--primary-blue);
    margin-bottom: var(--spacing-2);
}

.stat-label {
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    font-weight: 500;
}

/* =============================================================================
   ABOUT SECTION STYLES
   ============================================================================= */

#about {
    height: 100%;
    overflow: hidden;
    display: flex;
    flex-direction: column;
}

.about-content {
    margin-top: var(--content-top-offset);
    max-height: calc(100vh - var(--content-top-offset));
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-6);
    max-width: 600px;
    padding-right: var(--spacing-4);
}

.intro-text {
    font-size: var(--font-size-lg);
    font-weight: 500;
    color: var(--text-primary);
    margin-bottom: var(--spacing-6);
    line-height: 1.7;
}

.about-details {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-5);
}

.about-details p {
    font-size: var(--font-size-base);
    color: var(--text-secondary);
    line-height: 1.7;
}

.about-content::-webkit-scrollbar {
    width: 4px;
}

.about-content::-webkit-scrollbar-track {
    background: transparent;
    border-radius: 2px;
}

.about-content::-webkit-scrollbar-thumb {
    background: transparent;
    border-radius: 2px;
    transition: background 0.3s ease;
}

.about-content:hover::-webkit-scrollbar-thumb {
    background: #d1d5db;
}

.about-content::-webkit-scrollbar-thumb:hover {
    background: #9ca3af;
}

/* =============================================================================
   RESEARCH SECTION STYLES
   ============================================================================= */

#research {
    height: 100%;
    overflow: hidden;
}

.research-grid {
    margin-top: var(--content-top-offset);
    height: calc(100vh - var(--content-top-offset));
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-6);
    padding-right: var(--spacing-4);
    padding-bottom: var(--spacing-12);
}

.research-grid::-webkit-scrollbar {
    width: 4px;
}

.research-grid::-webkit-scrollbar-track {
    background: transparent;
    border-radius: 2px;
}

.research-grid::-webkit-scrollbar-thumb {
    background: #d1d5db;
    border-radius: 2px;
}

.research-grid::-webkit-scrollbar-thumb:hover {
    background: #9ca3af;
}

.research-card {
    display: flex;
    gap: var(--spacing-6);
    padding: var(--spacing-6);
    transition: all var(--transition-normal);
}

.research-card:hover {
    transform: none;
}

.research-image {
    flex-shrink: 0;
    width: 170px;
    height: 170px;
    position: relative;
    overflow: hidden;
    border-radius: var(--radius-md);
}

.research-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform var(--transition-normal);
}

.research-card:hover .research-image img {
    transform: none;
}

.image-placeholder {
    width: 100%;
    height: 100%;
    background-color: var(--primary-blue);
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 500;
    font-size: var(--font-size-sm);
}

.research-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-1);
}

.research-title {
    font-size: var(--font-size-xl);
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-2);
}

.research-caption {
    font-size: var(--font-size-base);
    color: var(--text-secondary);
    line-height: 1.6;
    flex: 1;
}

.read-more {
    color: var(--primary-blue);
    text-decoration: none;
    font-weight: 500;
    font-size: var(--font-size-sm);
    transition: color var(--transition-fast);
    align-self: flex-start;
}

.read-more:hover {
    color: var(--primary-blue-hover);
    text-decoration: underline;
}

/* =============================================================================
   PUBLICATIONS SECTION STYLES
   ============================================================================= */

#publications {
    height: 100%;
    overflow: hidden;
}

.publications-list {
    margin-top: var(--content-top-offset);
    height: calc(100vh - var(--content-top-offset));
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-6);
    padding-right: var(--spacing-4);
    padding-bottom: var(--spacing-12);
}

.publications-list::-webkit-scrollbar {
    width: 4px;
}

.publications-list::-webkit-scrollbar-track {
    background: transparent;
    border-radius: 2px;
}

.publications-list::-webkit-scrollbar-thumb {
    background: #d1d5db;
    border-radius: 2px;
}

.publications-list::-webkit-scrollbar-thumb:hover {
    background: #9ca3af;
}

.publication-card {
    display: flex;
    gap: var(--spacing-6);
    padding: var(--spacing-6);
    transition: all var(--transition-normal);
}

.publication-card:hover {
    transform: none;
}

.publication-image {
    flex-shrink: 0;
    width: 170px;
    height: 170px;
    position: relative;
    overflow: hidden;
    border-radius: var(--radius-md);
}

.publication-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform var(--transition-normal);
}

.publication-card:hover .publication-image img {
    transform: none;
}

.publication-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-2);
}

.publication-title {
    font-size: var(--font-size-xl);
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-2);
    line-height: 1.4;
}

.publication-authors {
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    font-weight: 500;
}

.publication-details {
    font-size: var(--font-size-sm);
    color: var(--text-light);
    display: flex;
    align-items: center;
    gap: var(--spacing-2);
}

.publication-link {
    color: var(--primary-blue);
    text-decoration: none;
    font-size: var(--font-size-sm);
    font-weight: 500;
    transition: color var(--transition-fast);
}

.publication-link:hover {
    color: var(--primary-blue-hover);
    text-decoration: underline;
}

/* =============================================================================
   GALLERY SECTION STYLES
   ============================================================================= */

#gallery {
    height: 100%;
    overflow: hidden;
}

.gallery-grid {
    margin-top: var(--content-top-offset);
    height: calc(100vh - var(--content-top-offset));
    overflow-y: auto;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--spacing-6);
    max-width: 600px;
    padding-right: var(--spacing-4);
    padding-bottom: var(--spacing-16);
}

.gallery-grid::-webkit-scrollbar {
    width: 4px;
}

.gallery-grid::-webkit-scrollbar-track {
    background: transparent;
    border-radius: 2px;
}

.gallery-grid::-webkit-scrollbar-thumb {
    background: #d1d5db;
    border-radius: 2px;
}

.gallery-grid::-webkit-scrollbar-thumb:hover {
    background: #9ca3af;
}

.gallery-item {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-3);
    transition: transform var(--transition-normal);
}

.gallery-item:hover {
    transform: none;
}

.gallery-image {
    width: 100%;
    height: 200px;
    position: relative;
    overflow: hidden;
    border-radius: var(--radius-md);
    background-color: var(--background-gray);
}

.gallery-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform var(--transition-normal);
}

.gallery-item:hover .gallery-image img {
    transform: scale(1.05);
}

.gallery-caption {
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    text-align: center;
    font-weight: 500;
    padding: 0 var(--spacing-2);
}

/* =============================================================================
   CONTACT SECTION STYLES
   ============================================================================= */

.contact-container {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-12);
}

.contact-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-6);
}

.contact-card {
    background-color: white;
    padding: var(--spacing-8);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    border: 1px solid var(--border-light);
    text-align: center;
    transition: all var(--transition-normal);
}

.contact-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary-blue-light);
}

.contact-icon {
    font-size: var(--font-size-4xl);
    margin-bottom: var(--spacing-4);
    display: block;
}

.contact-card h3 {
    font-size: var(--font-size-xl);
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-3);
}

.contact-card p {
    font-size: var(--font-size-base);
    color: var(--text-secondary);
    margin-bottom: var(--spacing-4);
    line-height: 1.6;
}

.contact-link {
    display: inline-block;
    background-color: var(--primary-blue);
    color: white;
    padding: var(--spacing-3) var(--spacing-5);
    border-radius: var(--radius-md);
    text-decoration: none;
    font-weight: 500;
    font-size: var(--font-size-sm);
    transition: all var(--transition-fast);
}

.contact-link:hover {
    background-color: var(--primary-blue-hover);
    transform: translateY(-1px);
    box-shadow: var(--shadow-sm);
}

/* Social Section */
.social-section {
    background-color: var(--background-gray);
    padding: var(--spacing-8);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-light);
}

.social-section h3 {
    font-size: var(--font-size-2xl);
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-6);
    text-align: center;
}

.social-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: var(--spacing-4);
}

.social-card {
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: var(--spacing-6);
    background-color: white;
    border-radius: var(--radius-lg);
    text-decoration: none;
    color: var(--text-primary);
    transition: all var(--transition-normal);
    border: 1px solid var(--border-light);
}

.social-card:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
    border-color: var(--primary-blue-light);
}

.social-icon {
    font-size: var(--font-size-3xl);
    margin-bottom: var(--spacing-3);
}

.social-card span {
    font-weight: 500;
    font-size: var(--font-size-sm);
}

/* Resources Section */
.resources-section {
    background-color: white;
    padding: var(--spacing-8);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-light);
    box-shadow: var(--shadow-sm);
}

.resources-section h3 {
    font-size: var(--font-size-2xl);
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-6);
    text-align: center;
}

.resources-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-4);
}

.resource-card {
    display: flex;
    align-items: center;
    padding: var(--spacing-6);
    background-color: var(--background-gray);
    border-radius: var(--radius-lg);
    text-decoration: none;
    color: var(--text-primary);
    transition: all var(--transition-normal);
    border: 1px solid var(--border-light);
    gap: var(--spacing-4);
}

.resource-card:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
    border-color: var(--primary-blue-light);
    background-color: white;
}

.resource-icon {
    font-size: var(--font-size-2xl);
    flex-shrink: 0;
}

.resource-content h4 {
    font-size: var(--font-size-lg);
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-2);
}

.resource-content p {
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    line-height: 1.5;
}

/* =============================================================================
   MORE SECTION STYLES (Legacy - keeping for compatibility)
   ============================================================================= */

.more-content {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-8);
    max-width: 600px;
}

.more-content h3 {
    font-size: var(--font-size-xl);
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-4);
}

.more-content p {
    font-size: var(--font-size-base);
    color: var(--text-secondary);
    line-height: 1.6;
    margin-bottom: var(--spacing-2);
}

.more-content strong {
    color: var(--text-primary);
    font-weight: 600;
}

.social-buttons {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-3);
}

.social-link {
    display: inline-block;
    padding: var(--spacing-3) var(--spacing-5);
    background-color: var(--primary-blue);
    color: white;
    text-decoration: none;
    border-radius: var(--radius-md);
    font-size: var(--font-size-sm);
    font-weight: 500;
    transition: all var(--transition-fast);
}

.social-link:hover {
    background-color: var(--primary-blue-hover);
    transform: translateY(-1px);
    box-shadow: var(--shadow-sm);
}

.additional-info ul {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-2);
}

.additional-info li {
    padding: var(--spacing-2) 0;
}

.additional-info a {
    color: var(--primary-blue);
    text-decoration: none;
    font-weight: 500;
    transition: color var(--transition-fast);
}

.additional-info a:hover {
    color: var(--primary-blue-hover);
    text-decoration: underline;
}

/* =============================================================================
   RESPONSIVE DESIGN
   ============================================================================= */

/* Large Mobile and Small Tablet */
@media (max-width: 1024px) {
    :root {
        --sidebar-width: 380px;
        --content-max-width: 600px;
    }
    
    .container {
        max-width: 1000px;
    }
    
    .research-card,
    .publication-card {
        gap: var(--spacing-4);
        padding: var(--spacing-4);
    }
    
    .research-image,
    .publication-image {
        width: 150px;
        height: 150px;
    }
    
    .gallery-grid {
        grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    }
}

/* Tablet and Mobile Responsive */
@media (max-width: 768px) {
    :root {
        --sidebar-width: 45vw;
        --spacing-8: 1.5rem;
        --spacing-12: 2rem;
    }
    
    .sidebar {
        width: var(--sidebar-width);
        padding: var(--spacing-6) var(--spacing-4);
    }
    
    .name {
        font-size: var(--font-size-2xl);
    }
    
    .content-area {
        margin-left: var(--sidebar-width);
        padding: var(--spacing-6) var(--spacing-8);
    }
    
    .separator {
        left: var(--sidebar-width);
    }
    
    .research-card,
    .publication-card {
        flex-direction: column;
        text-align: center;
        padding: var(--spacing-4);
        gap: var(--spacing-4);
    }
    
    .research-image,
    .publication-image {
        width: 100%;
        max-width: 250px;
        height: 200px;
        align-self: center;
        margin: 0 auto;
    }
    
    .research-content,
    .publication-content {
        gap: var(--spacing-3);
    }
    
    .research-title,
    .publication-title {
        font-size: var(--font-size-lg);
    }
    
    .research-caption,
    .publication-authors {
        font-size: var(--font-size-sm);
    }
    
    .gallery-grid {
        grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
        gap: var(--spacing-4);
    }
    
    /* Landing page responsive */
    .landing-content {
        grid-template-columns: 1fr;
        gap: var(--spacing-8);
        text-align: center;
    }
    
    .photo-container {
        width: 250px;
        height: 250px;
        margin: 0 auto;
    }
    
    .quick-stats {
        grid-template-columns: repeat(2, 1fr);
        gap: var(--spacing-4);
    }
    
    .landing-cta {
        justify-content: center;
        flex-wrap: wrap;
    }
    
    .contact-grid {
        grid-template-columns: 1fr;
    }
    
    .social-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .resources-grid {
        grid-template-columns: 1fr;
    }
}

/* Mobile Landscape */
@media (max-width: 640px) {
    :root {
        --sidebar-width: 100%;
        --spacing-8: 1rem;
        --spacing-12: 1.5rem;
        --font-size-2xl: 1.75rem;
        --font-size-xl: 1.25rem;
        --font-size-lg: 1.125rem;
    }
    
    .container {
        flex-direction: column;
        max-width: 100%;
    }
    
    .sidebar {
        position: static;
        width: 100%;
        height: auto;
        border-right: none;
        border-bottom: var(--separator-width) solid var(--border-light);
        padding: var(--spacing-6) var(--spacing-4);
    }
    
    .profile {
        text-align: center;
        padding: 0;
        margin-top: var(--spacing-4);
    }
    
    .navigation {
        margin-top: var(--spacing-6);
        padding: 0;
    }
    
    .nav-list {
        flex-direction: row;
        justify-content: space-around;
        flex-wrap: wrap;
        gap: var(--spacing-2);
    }
    
    .nav-item {
        flex: 1;
        min-width: 80px;
    }
    
    .nav-link {
        flex-direction: column;
        text-align: center;
        padding: var(--spacing-3);
        gap: var(--spacing-1);
    }
    
    .nav-text {
        font-size: var(--font-size-sm);
    }
    
    .separator {
        display: none;
    }
    
    .content-area {
        margin-left: 0;
        padding: var(--spacing-4);
    }
    
    .research-grid,
    .publications-list,
    .gallery-grid,
    .about-content {
        margin-top: var(--spacing-4);
        height: calc(100vh - 200px);
        padding: var(--spacing-4);
    }
    
    .research-card,
    .publication-card {
        padding: var(--spacing-3);
        margin-bottom: var(--spacing-4);
    }
    
    .research-image,
    .publication-image {
        width: 100%;
        max-width: 200px;
        height: 150px;
    }
    
    .gallery-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: var(--spacing-3);
    }
    
    .gallery-item {
        gap: var(--spacing-2);
    }
    
    .gallery-image {
        height: 150px;
    }
    
    .landing-container {
        padding: var(--spacing-4);
        height: calc(100vh - 120px);
    }
    
    .profile-photo {
        margin-top: var(--spacing-8);
    }
    
    .photo-container {
        width: 200px;
        height: 200px;
    }
    
    .home-social-icons {
        margin-top: var(--spacing-4);
        gap: var(--spacing-3);
    }
    
    .home-social-icons a img {
        width: 20px;
        height: 20px;
    }
    
    .nav-list {
        flex-direction: row;
        gap: var(--spacing-2);
        overflow-x: auto;
    }
}

/* Very Small Mobile Devices */
@media (max-width: 480px) {
    :root {
        --spacing-8: 0.75rem;
        --spacing-12: 1rem;
        --font-size-2xl: 1.5rem;
        --font-size-xl: 1.125rem;
        --font-size-lg: 1rem;
        --font-size-base: 0.875rem;
    }
    
    .container {
        padding: 0;
    }
    
    .sidebar {
        padding: var(--spacing-4) var(--spacing-3);
    }
    
    .profile {
        margin-top: var(--spacing-2);
    }
    
    .name {
        font-size: var(--font-size-2xl);
        letter-spacing: 0.04em;
    }
    
    .title {
        font-size: var(--font-size-sm);
    }
    
    .nav-list {
        gap: var(--spacing-1);
    }
    
    .nav-link {
        padding: var(--spacing-2);
        gap: 0;
    }
    
    .nav-icon img {
        width: 14px;
        height: 14px;
    }
    
    .nav-text {
        font-size: 0.75rem;
    }
    
    .content-area {
        padding: var(--spacing-3);
    }
    
    .research-grid,
    .publications-list,
    .gallery-grid,
    .about-content {
        margin-top: var(--spacing-2);
        height: calc(100vh - 180px);
        padding: var(--spacing-2);
    }
    
    .research-card,
    .publication-card {
        padding: var(--spacing-2);
        margin-bottom: var(--spacing-3);
    }
    
    .research-image,
    .publication-image {
        max-width: 150px;
        height: 120px;
    }
    
    .research-title,
    .publication-title {
        font-size: var(--font-size-base);
        line-height: 1.3;
    }
    
    .research-caption,
    .publication-authors {
        font-size: 0.75rem;
        line-height: 1.4;
    }
    
    .gallery-grid {
        grid-template-columns: 1fr;
        gap: var(--spacing-2);
    }
    
    .gallery-image {
        height: 120px;
    }
    
    .landing-container {
        padding: var(--spacing-3);
        height: calc(100vh - 100px);
    }
    
    .profile-photo {
        margin-top: var(--spacing-6);
    }
    
    .photo-container {
        width: 150px;
        height: 150px;
    }
    
    .home-social-icons {
        margin-top: var(--spacing-3);
        gap: var(--spacing-2);
    }
    
    .home-social-icons a img {
        width: 18px;
        height: 18px;
    }
    
    .about-content {
        gap: var(--spacing-3);
    }
    
    .intro-text {
        font-size: var(--font-size-base);
        line-height: 1.5;
    }
    
    .about-details p {
        font-size: var(--font-size-sm);
        line-height: 1.5;
    }
    
    .about-details h3 {
        font-size: var(--font-size-base);
        margin-bottom: var(--spacing-2);
    }
    
    .nav-item {
        flex-shrink: 0;
    }
    
    .gallery-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    /* Mobile landing page */
    .quick-stats {
        grid-template-columns: 1fr;
        gap: var(--spacing-3);
    }
    
    .photo-container {
        width: 200px;
        height: 200px;
    }
    
    .landing-cta {
        flex-direction: column;
        align-items: center;
    }
    
    .cta-button {
        width: 100%;
        max-width: 300px;
        justify-content: center;
    }
    
    .social-grid {
        grid-template-columns: 1fr;
    }
}

/* =============================================================================
   ACCESSIBILITY & INTERACTIONS
   ============================================================================= */

/* Focus States for Accessibility */
.nav-link:focus,
.read-more:focus,
.publication-button:focus,
.social-link:focus,
.additional-info a:focus {
    outline: 2px solid var(--primary-blue);
    outline-offset: 2px;
}

/* Smooth Scrolling */
html {
    scroll-behavior: smooth;
}

/* Loading States */
.loading {
    opacity: 0.6;
    pointer-events: none;
}

/* =============================================================================
   PRINT STYLES
   ============================================================================= */

@media print {
    .sidebar {
        position: static;
        width: 100%;
        height: auto;
        border-right: none;
        border-bottom: 2px solid var(--text-primary);
    }
    
    .separator {
        display: none;
    }
    
    .content-area {
        margin-left: 0;
    }
    
    .nav-link:hover,
    .research-card:hover,
    .publication-card:hover,
    .gallery-item:hover {
        transform: none;
        box-shadow: none;
    }
}