/* ============================================
   GLOBAL STYLES & VARIABLES
   ============================================ */

:root {
    --primary-color: #1e3a8a;
    --secondary-color: #3b82f6;
    --accent-color: #06b6d4;
    --dark-bg: #0f172a;
    --light-bg: #f8fafc;
    --text-dark: #1e293b;
    --text-light: #64748b;
    --border-color: #e2e8f0;
    --success-color: #10b981;
    --warning-color: #f59e0b;
    --danger-color: #ef4444;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen', 'Ubuntu', 'Cantarell', 'Fira Sans', 'Droid Sans', 'Helvetica Neue', sans-serif;
    line-height: 1.6;
    color: var(--text-dark);
    background-color: #ffffff;
    overflow-x: hidden;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}




/* Publication badges */
.pub-badge {
    display: inline-block;
    padding: 4px 12px;
    border-radius: 12px;
    font-size: 12px;
    font-weight: 500;
    margin-right: 8px;
}

.pub-badge.first-author {
    background-color: rgba(33, 128, 141, 0.15);
    color: var(--color-teal-500);
    border: 1px solid rgba(33, 128, 141, 0.3);
}

.pub-badge.shared-first {
    background-color: rgba(50, 184, 198, 0.15);
    color: var(--color-teal-300);
    border: 1px solid rgba(50, 184, 198, 0.3);
}

.pub-badge.co-author {
    background-color: rgba(98, 108, 113, 0.15);
    color: var(--color-slate-500);
    border: 1px solid rgba(98, 108, 113, 0.3);
}

.pub-badge.senior-author {
    background-color: rgba(168, 75, 47, 0.15);
    color: var(--color-orange-500);
    border: 1px solid rgba(168, 75, 47, 0.3);
}

.pub-badge.gbd {
    background-color: rgba(94, 82, 64, 0.15);
    color: var(--color-brown-600);
    border: 1px solid rgba(94, 82, 64, 0.3);
}

/* Dark mode badge colors */
@media (prefers-color-scheme: dark) {
    .pub-badge.first-author {
        background-color: rgba(50, 184, 198, 0.15);
        color: var(--color-teal-300);
        border: 1px solid rgba(50, 184, 198, 0.3);
    }
}

[data-color-scheme="dark"] .pub-badge.first-author {
    background-color: rgba(50, 184, 198, 0.15);
    color: var(--color-teal-300);
    border: 1px solid rgba(50, 184, 198, 0.3);
}

.__dimensions_badge_embed__ {
    display: inline-block !important;
}


/* ============================================
   NAVIGATION BAR
   ============================================ */

.navbar {
    position: sticky;
    top: 0;
    z-index: 1000;
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    padding: 1rem 0;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-brand a {
    font-size: 1.5rem;
    font-weight: 700;
    color: white;
    text-decoration: none;
    transition: var(--transition);
}

.nav-brand a:hover {
    opacity: 0.9;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-link {
    color: rgba(255, 255, 255, 0.9);
    text-decoration: none;
    font-size: 0.95rem;
    font-weight: 500;
    transition: var(--transition);
    border-bottom: 2px solid transparent;
    padding-bottom: 0.25rem;
}

.nav-link:hover {
    color: white;
    border-bottom-color: var(--accent-color);
}

.hamburger {
    display: none;
    flex-direction: column;
    cursor: pointer;
}

.hamburger span {
    width: 25px;
    height: 3px;
    background-color: white;
    margin: 5px 0;
    transition: var(--transition);
    border-radius: 3px;
}

/* ============================================
   HERO SECTION
   ============================================ */

.hero {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 50%, var(--accent-color) 100%);
    color: white;
    padding: 100px 0 100px 3rem;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -10%;
    width: 500px;
    height: 500px;
    background: rgba(255, 255, 255, 0.05);
    border-radius: 50%;
    animation: float 6s ease-in-out infinite;
}

@keyframes float {
    0%, 100% { transform: translateY(0px); }
    50% { transform: translateY(30px); }
}

.hero-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    align-items: center;
    position: relative;
    z-index: 2;
    padding-right: 3rem;
}

.hero-text {
    padding-right: 2rem;
}

.hero-text h1 {
    font-size: 3.5rem;
    margin-bottom: 0.5rem;
    line-height: 1.1;
    font-weight: 800;
}

.hero-text .title {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: rgba(255, 255, 255, 0.95);
}

.hero-text .subtitle {
    font-size: 1.1rem;
    color: rgba(255, 255, 255, 0.85);
    margin-bottom: 2rem;
    line-height: 1.6;
}

.hero-buttons {
    display: flex;
    gap: 1rem;
    margin-bottom: 2rem;
}

.btn {
    padding: 12px 24px;
    border: none;
    border-radius: 6px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    text-decoration: none;
    display: inline-block;
    text-align: center;
}

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

.btn-primary:hover {
    background-color: #0891b2;
    transform: translateY(-2px);
    box-shadow: 0 10px 20px rgba(6, 182, 212, 0.3);
}

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

.btn-secondary:hover {
    background-color: var(--light-bg);
    transform: translateY(-2px);
}

.social-links {
    display: flex;
    gap: 1.5rem;
}

.social-links a {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 50px;
    height: 50px;
    background-color: rgba(255, 255, 255, 0.1);
    border-radius: 50%;
    color: white;
    transition: var(--transition);
    border: 2px solid transparent;
}

.social-links a:hover {
    background-color: rgba(255, 255, 255, 0.2);
    border-color: var(--accent-color);
}

.icon {
    width: 24px;
    height: 24px;
    fill: currentColor;
}

.hero-image {
    display: flex;
    justify-content: center;
    align-items: center;
}

.profile-photo {
    width: 300px;
    height: 300px;
    border-radius: 12px;
    object-fit: cover;
    border: 4px solid rgba(255, 255, 255, 0.3);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.3);
    animation: fadeInUp 0.8s ease forwards;
}

.placeholder-image {
    width: 250px;
    height: 250px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    border: 3px solid rgba(255, 255, 255, 0.2);
    color: white;
    font-size: 100px;
    animation: pulse 3s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.7; }
}

/* ============================================
   SECTIONS
   ============================================ */

section {
    padding: 80px 0;
}

section h2 {
    font-size: 2.5rem;
    margin-bottom: 3rem;
    color: var(--primary-color);
    text-align: center;
    position: relative;
}

section h2::after {
    content: '';
    display: block;
    width: 100px;
    height: 4px;
    background: var(--secondary-color);
    margin: 1rem auto 0;
    border-radius: 2px;
}

.about {
    background-color: var(--light-bg);
}

.about p {
    font-size: 1.1rem;
    color: var(--text-light);
    margin-bottom: 1.5rem;
    line-height: 1.8;
}

/* ============================================
   RESEARCH INTERESTS
   ============================================ */

.research-interests {
    background-color: white;
}

.interests-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.interest-card {
    background: var(--light-bg);
    padding: 2rem;
    border-radius: 8px;
    border-left: 4px solid var(--secondary-color);
    transition: var(--transition);
    cursor: pointer;
}

.interest-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
}

.interest-card h3 {
    color: var(--primary-color);
    margin-bottom: 0.5rem;
}

.interest-card p {
    color: var(--text-light);
    font-size: 0.95rem;
}

/* ============================================
   TIMELINE
   ============================================ */

/* TIMELINE LAYOUT (unchanged) */
.education-timeline,
.experience-timeline {
    position: relative;
    padding-left: 2rem;
}

.education-timeline::before,
.experience-timeline::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    bottom: 0;
    width: 3px;
    background: linear-gradient(180deg, var(--secondary-color), var(--accent-color));
}

.timeline-item {
    position: relative;
    margin-bottom: 2rem;
    padding-bottom: 2rem;
}

.timeline-content {
    margin-left: 1.5rem;
}

/* Base marker (visible circle) */
.timeline-marker {
    position: absolute;
    left: -14px;
    top: 5px;
    width: 24px;
    height: 24px;
    border-radius: 50%;
    background: #ffffff;
    border: 3px solid var(--secondary-color);
    box-shadow: 0 0 0 4px var(--light-bg);
    background-repeat: no-repeat;
    background-position: center;
    background-size: cover;
}

/* EDUCATION: same SUST logo for both degrees */
.education-timeline .timeline-item .timeline-marker {
    background-image: url("assets/SUST logo.png");
}

/* EXPERIENCE: use company‑specific logos */
.experience-timeline .timeline-item.icddrb .timeline-marker {
    background-image: url("assets/icddrb-Logo-Vector.svg-.png");
}

.experience-timeline .timeline-item.sust .timeline-marker {
    background-image: url("assets/SUST logo.png");
}

.experience-timeline .timeline-item.staffasia .timeline-marker {
    background-image: url("assets/staff-asia-logo-2.png");
}

/* TEXT STYLES (unchanged) */
.timeline-content h3 {
    font-size: 1.3rem;
    color: var(--primary-color);
    margin-bottom: 0.5rem;
}

.timeline-content .institution {
    color: var(--secondary-color);
    font-weight: 600;
    margin-bottom: 0.25rem;
}

.timeline-content .period {
    color: var(--text-light);
    font-size: 0.95rem;
    font-weight: 500;
}

.timeline-content .details {
    color: var(--text-light);
    font-size: 0.9rem;
    margin-top: 0.25rem;
}

.timeline-content .thesis {
    margin-top: 0.75rem;
    padding: 0.75rem;
    background-color: var(--light-bg);
    border-radius: 4px;
    font-size: 0.95rem;
}

.responsibilities {
    list-style: none;
    margin-top: 1rem;
}

.responsibilities li {
    padding: 0.5rem 0 0.5rem 1.5rem;
    position: relative;
    color: var(--text-light);
}

.responsibilities li::before {
    content: '→';
    position: absolute;
    left: 0;
    color: var(--secondary-color);
    font-weight: bold;
}


/* ============================================
   TRAINING SECTION
   ============================================ */

.training {
    background-color: white;
}

.training-slider {
    position: relative;
    overflow: hidden;
    border-radius: 12px;
}

.training-carousel {
    display: flex;
    transition: transform 0.6s cubic-bezier(0.4, 0, 0.2, 1);
    width: 100%;
}

.training-slide {
    min-width: 100%;
    flex: 0 0 100%;
    padding: 0;
    animation: slideInFromRight 0.6s ease-out;
}

@keyframes slideInFromRight {
    from {
        opacity: 0;
        transform: translateX(100px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

@keyframes slideInFromLeft {
    from {
        opacity: 0;
        transform: translateX(-100px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

.training-slide.prev-animation {
    animation: slideInFromLeft 0.6s ease-out;
}

.training-card {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
    align-items: center;
    background: var(--light-bg);
    padding: 2rem;
    border-radius: 12px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.08);
    transition: all 0.3s ease;
}

.training-card:hover {
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.12);
    transform: translateY(-5px);
}

.training-image {
    overflow: hidden;
    border-radius: 8px;
    height: 350px;
}

.training-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.3s ease;
}

.training-card:hover .training-image img {
    transform: scale(1.05);
}

.training-content {
    padding: 1rem;
}

.training-content h3 {
    font-size: 1.4rem;
    color: var(--primary-color);
    margin-bottom: 1rem;
    line-height: 1.4;
}

.training-organization {
    color: var(--secondary-color);
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.training-location {
    color: var(--text-light);
    font-size: 0.95rem;
    margin-bottom: 0.5rem;
}

.training-date {
    color: var(--text-dark);
    font-size: 0.95rem;
    margin-top: 1rem;
    padding-top: 1rem;
    border-top: 2px solid var(--border-color);
}

/* Carousel Navigation Buttons */
.carousel-btn {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    width: 50px;
    height: 50px;
    border: 2px solid var(--secondary-color);
    background-color: white;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 10;
    transition: all 0.3s ease;
}

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

.carousel-btn:hover svg {
    color: white;
}

.carousel-btn svg {
    width: 24px;
    height: 24px;
    color: var(--secondary-color);
    transition: color 0.3s ease;
}

.carousel-btn-prev {
    left: 20px;
}

.carousel-btn-next {
    right: 20px;
}

/* Carousel Indicators */
.carousel-indicators {
    position: absolute;
    bottom: 20px;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    gap: 0.75rem;
    z-index: 10;
}

.indicator {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    border: 2px solid var(--secondary-color);
    background-color: white;
    cursor: pointer;
    transition: all 0.3s ease;
}

.indicator.active {
    background-color: var(--secondary-color);
}

.indicator:hover {
    transform: scale(1.2);
}

/* ============================================
   PUBLICATIONS
   ============================================ */

.publications {
    background-color: var(--light-bg);
}

.publications-controls {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
    margin-bottom: 2rem;
    align-items: center;
}

.search-box {
    flex: 1;
    min-width: 250px;
    position: relative;
    display: flex;
    align-items: center;
}

.search-box input {
    width: 100%;
    padding: 12px 40px 12px 16px;
    border: 2px solid var(--border-color);
    border-radius: 6px;
    font-size: 1rem;
    transition: var(--transition);
}

.search-box input:focus {
    outline: none;
    border-color: var(--secondary-color);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

.search-icon {
    position: absolute;
    right: 12px;
    width: 20px;
    height: 20px;
    color: var(--text-light);
    pointer-events: none;
}

.filter-buttons {
    display: flex;
    gap: 0.5rem;
}

.filter-btn {
    padding: 8px 16px;
    border: 2px solid var(--border-color);
    background: white;
    color: var(--text-dark);
    border-radius: 6px;
    cursor: pointer;
    font-weight: 500;
    transition: var(--transition);
}

.filter-btn:hover {
    border-color: var(--secondary-color);
    color: var(--secondary-color);
}

.filter-btn.active {
    background: var(--secondary-color);
    color: white;
    border-color: var(--secondary-color);
}

.metrics-summary {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1.5rem;
    margin-bottom: 3rem;
}

.metric-card {
    background: white;
    padding: 2rem;
    border-radius: 8px;
    text-align: center;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
    border-top: 4px solid var(--secondary-color);
}

.metric-value {
    font-size: 2.5rem;
    font-weight: 800;
    color: var(--secondary-color);
    margin-bottom: 0.5rem;
}

.metric-label {
    color: var(--text-light);
    font-weight: 600;
    text-transform: uppercase;
    font-size: 0.85rem;
    letter-spacing: 1px;
}

.publications-list {
    display: grid;
    gap: 1.5rem;
}

.publication-item {
    background: white;
    padding: 2rem;
    border-radius: 8px;
    border-left: 4px solid var(--secondary-color);
    transition: var(--transition);
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
}

.publication-item:hover {
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
    transform: translateY(-5px);
}

.publication-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 1rem;
    gap: 1rem;
}

.publication-header h3 {
    color: var(--primary-color);
    line-height: 1.4;
    margin: 0;
    flex: 1;
}

.pub-year {
    background: var(--light-bg);
    padding: 4px 12px;
    border-radius: 20px;
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--text-light);
    white-space: nowrap;
}

.pub-authors {
    color: var(--text-light);
    font-size: 0.95rem;
    margin-bottom: 0.5rem;
}

.pub-authors strong {
    color: var(--text-dark);
}

.pub-journal {
    color: var(--secondary-color);
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.pub-doi {
    color: var(--text-light);
    font-size: 0.9rem;
    margin-bottom: 1rem;
    word-break: break-all;
}

.pub-footer {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-top: 1rem;
    border-top: 1px solid var(--border-color);
    flex-wrap: wrap;
    gap: 1rem;
}

.citation-count {
    color: var(--text-light);
    font-weight: 500;
}

.pub-link {
    color: var(--secondary-color);
    text-decoration: none;
    font-weight: 600;
    transition: var(--transition);
}

.pub-link:hover {
    text-decoration: underline;
}

.loading-message {
    text-align: center;
    padding: 3rem;
    color: var(--text-light);
}

.spinner {
    border: 4px solid var(--light-bg);
    border-top: 4px solid var(--secondary-color);
    border-radius: 50%;
    width: 40px;
    height: 40px;
    animation: spin 1s linear infinite;
    margin: 0 auto 1rem;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

/* ============================================
   METRICS SECTION
   ============================================ */

/* ============================================
   AWARDS SECTION
   ============================================ */

.awards {
    background-color: var(--light-bg);
}

.awards-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
}

.award-card {
    background: white;
    padding: 2rem;
    border-radius: 8px;
    text-align: center;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
    border-top: 4px solid var(--accent-color);
    transition: var(--transition);
}

.award-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
}

.award-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.award-card h3 {
    color: var(--primary-color);
    margin-bottom: 0.5rem;
}

.award-card p {
    color: var(--text-light);
}

/* ============================================
   SKILLS SECTION
   ============================================ */

.skills {
    background-color: white;
}

.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
}

.skill-category {
    background: var(--light-bg);
    padding: 2rem;
    border-radius: 8px;
    border-left: 4px solid var(--secondary-color);
}

.skill-category h3 {
    color: var(--primary-color);
    margin-bottom: 1rem;
}

.skill-category ul {
    list-style: none;
}

.skill-category li {
    padding: 0.5rem 0 0.5rem 1.5rem;
    color: var(--text-light);
    position: relative;
}

.skill-category li::before {
    content: '✓';
    position: absolute;
    left: 0;
    color: var(--success-color);
    font-weight: bold;
    font-size: 1.1rem;
}

/* ============================================
   SERVICE & LEADERSHIP SECTION
   ============================================ */

.service {
    background-color: var(--light-bg);
}

.service-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.service-card {
    background: white;
    padding: 2rem;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
    border-top: 4px solid var(--accent-color);
}

.service-card h3 {
    color: var(--primary-color);
    margin-bottom: 1rem;
}

.service-card p {
    color: var(--text-light);
    line-height: 1.7;
}

.service-card ul {
    list-style: none;
    color: var(--text-light);
}

.service-card li {
    padding: 0.5rem 0;
    line-height: 1.6;
}

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

.contact {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    color: white;
    position: relative;
    overflow: hidden;
}

.contact::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -10%;
    width: 500px;
    height: 500px;
    background: rgba(255, 255, 255, 0.05);
    border-radius: 50%;
}

.contact h2 {
    color: white;
}

.contact h2::after {
    background-color: var(--accent-color);
}

.contact-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    position: relative;
    z-index: 2;
}

.contact-info h3 {
    color: white;
    margin-bottom: 2rem;
    font-size: 1.3rem;
}

.contact-item {
    margin-bottom: 1.5rem;
}

.contact-label {
    display: block;
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: rgba(255, 255, 255, 0.9);
}

.contact-item a {
    color: var(--accent-color);
    text-decoration: none;
    transition: var(--transition);
}

.contact-item a:hover {
    text-decoration: underline;
}

.contact-item span {
    color: rgba(255, 255, 255, 0.9);
}

.contact-form {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.form-group {
    display: flex;
    flex-direction: column;
}

.form-group input,
.form-group textarea {
    padding: 12px 16px;
    border: 2px solid rgba(255, 255, 255, 0.2);
    border-radius: 6px;
    background-color: rgba(255, 255, 255, 0.1);
    color: white;
    font-size: 1rem;
    transition: var(--transition);
    font-family: inherit;
}

.form-group input::placeholder,
.form-group textarea::placeholder {
    color: rgba(255, 255, 255, 0.7);
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--accent-color);
    background-color: rgba(255, 255, 255, 0.15);
}

/* ============================================
   FOOTER
   ============================================ */

.footer {
    background-color: var(--dark-bg);
    color: rgba(255, 255, 255, 0.7);
    padding: 2rem 0;
    text-align: center;
}

.footer p {
    margin: 0.5rem 0;
}

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

@media (max-width: 768px) {
    .hamburger {
        display: flex;
    }

    .nav-menu {
        position: fixed;
        left: -100%;
        top: 60px;
        flex-direction: column;
        background-color: var(--primary-color);
        width: 100%;
        text-align: center;
        transition: 0.3s;
        gap: 0;
        padding: 2rem 0;
    }

    .nav-menu.active {
        left: 0;
    }

    .nav-link {
        padding: 1rem 0;
    }

    .hero-text h1 {
        font-size: 2rem;
    }

    .hero-text .title {
        font-size: 1.1rem;
    }

    .hero-content {
        grid-template-columns: 1fr;
    }

    .hero-image {
        order: -1;
    }

    .hero-buttons {
        flex-direction: column;
    }

    .btn {
        width: 100%;
    }

    section {
        padding: 50px 0;
    }

    section h2 {
        font-size: 2rem;
    }

    .interests-grid,
    .awards-grid,
    .skills-grid,
    .service-grid {
        grid-template-columns: 1fr;
    }

    .contact-content {
        grid-template-columns: 1fr;
    }

    .contact-form {
        order: -1;
    }

    .publications-controls {
        flex-direction: column;
    }

    .search-box {
        min-width: 100%;
    }

    .filter-buttons {
        flex-wrap: wrap;
        width: 100%;
    }

    .publication-header {
        flex-direction: column;
    }

    .pub-year {
        align-self: flex-start;
    }

    .pub-footer {
        flex-direction: column;
        align-items: flex-start;
    }

    /* Training Section Responsive */
    .training-card {
        grid-template-columns: 1fr;
        padding: 1.5rem;
        gap: 1.5rem;
    }

    .training-image {
        height: 280px;
    }

    .training-content h3 {
        font-size: 1.1rem;
    }

    .carousel-btn {
        width: 40px;
        height: 40px;
    }

    .carousel-btn svg {
        width: 20px;
        height: 20px;
    }

    .carousel-btn-prev {
        left: 10px;
    }

    .carousel-btn-next {
        right: 10px;
    }
}

@media (max-width: 480px) {
    .hero-text h1 {
        font-size: 1.5rem;
    }

    .hero-text .subtitle {
        font-size: 0.9rem;
    }

    .social-links {
        gap: 1rem;
    }

    .social-links a {
        width: 40px;
        height: 40px;
    }

    .placeholder-image {
        width: 150px;
        height: 150px;
    }

    .nav-menu {
        padding: 1rem 0;
    }

    .nav-link {
        padding: 0.75rem 0;
    }

    section h2 {
        font-size: 1.5rem;
    }

    .timeline-item {
        padding-left: 0;
        margin-bottom: 1.5rem;
    }

    .timeline-marker {
        left: -12px;
    }

    .interests-grid,
    .education-timeline,
    .experience-timeline {
        padding-left: 0;
    }

    .education-timeline::before,
    .experience-timeline::before {
        left: 0;
        display: none;
    }

    .interest-card {
        border-left-width: 0;
        border-top: 4px solid var(--secondary-color);
    }

    .publication-item {
        border-left: none;
        border-top: 4px solid var(--secondary-color);
    }
}

/* ============================================
   UTILITY CLASSES
   ============================================ */

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

.mt-1 { margin-top: 0.5rem; }
.mt-2 { margin-top: 1rem; }
.mt-3 { margin-top: 1.5rem; }
.mt-4 { margin-top: 2rem; }

.mb-1 { margin-bottom: 0.5rem; }
.mb-2 { margin-bottom: 1rem; }
.mb-3 { margin-bottom: 1.5rem; }
.mb-4 { margin-bottom: 2rem; }

.hidden {
    display: none !important;
}

.visible {
    display: block !important;
}