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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', sans-serif;
    line-height: 1.6;
    color: #000000;
    background-color: #ffffff;
}

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

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.2;
    margin-bottom: 1rem;
    color: #000000;
}

h1 {
    font-size: 2.5rem;
    font-weight: 700;
}

h2 {
    font-size: 2rem;
}

h3 {
    font-size: 1.3rem;
}

p {
    margin-bottom: 1rem;
    color: #333333;
}

/* Navigation */
.navbar {
    position: fixed;
    top: 0;
    width: 100%;
    background: rgba(255, 255, 255, 0.98);
    backdrop-filter: blur(10px);
    z-index: 1000;
    padding: 1rem 0;
    transition: all 0.3s ease;
    border-bottom: 1px solid #e0e0e0;
}

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

.nav-logo a {
    font-size: 1.5rem;
    font-weight: 700;
    color: #000000;
    text-decoration: none;
    transition: color 0.3s ease;
}

.nav-logo a:hover {
    color: #666666;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 2rem;
    align-items: center;
    padding-left: 0;
}

.nav-item {
    list-style: none;
    position: static;
    padding-left: 0;
    margin-bottom: 0;
}

.nav-item::before {
    content: none;
    display: none;
}

.nav-link {
    color: #000000;
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s ease;
    position: relative;
}

.nav-link:hover,
.nav-link.active {
    color: #666666;
}

.nav-link::after {
    content: '';
    position: absolute;
    width: 0;
    height: 2px;
    bottom: -5px;
    left: 0;
    background-color: #000000;
    transition: width 0.3s ease;
}

.nav-link:hover::after,
.nav-link.active::after {
    width: 100%;
}

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

.bar {
    width: 25px;
    height: 3px;
    background-color: #000000;
    margin: 3px 0;
    transition: 0.3s;
}

/* Main Content */
.main-content {
    padding-top: 100px;
    min-height: calc(100vh - 100px);
}

.inline-image {
    width: 20px;
    height: 20px;
}

/* Home Layout */
.home-layout {
    display: grid;
    grid-template-columns: 250px 1fr;
    gap: 4rem;
    align-items: start;
    padding: 2rem 0;
}

/* Portrait Section */
.portrait-section {
    position: sticky;
    top: 120px;
}

.portrait-container {
    display: flex;
    justify-content: center;
    align-items: center;
}

.portrait-placeholder {
    width: 150px;
    height: 150px;
    background: #f5f5f5;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 3rem;
    color: #666666;
    border: 2px solid #e0e0e0;
}

.portrait-image {
    width: 150px;
    height: 150px;
    border-radius: 50%;
    object-fit: cover;
}

.email-section {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    margin-top: 2rem;
}

/* News Section */
.news-section {
    margin: 2rem 0;
}

.news-title {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 1.5rem;
    color: #000000;
    border-bottom: 2px solid #f0f0f0;
    padding-bottom: 0.5rem;
}

.news-list {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.news-item {
    display: flex;
    gap: 1rem;
    padding: 1rem;
    background: #fafafa;
    border-radius: 8px;
    border-left: 4px solid #007acc;
    transition: all 0.3s ease;
}

.news-item:hover {
    background: #f5f5f5;
    transform: translateX(5px);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.news-date {
    font-size: 0.9rem;
    font-weight: 600;
    color: #007acc;
    min-width: 80px;
    text-align: center;
    background: #e8f4fd;
    padding: 0.5rem;
    border-radius: 4px;
    height: fit-content;
}

.news-content {
    flex: 1;
    font-size: 1rem;
    line-height: 1.6;
    color: #333333;
}

.news-content strong {
    color: #000000;
    font-weight: 600;
}

/* Social Links Sidebar */
.social-links-sidebar {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    margin-top: 2rem;
    align-items: center;
}

.social-link-icon {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 50px;
    height: 50px;
    background: #f5f5f5;
    border-radius: 50%;
    color: #666666;
    text-decoration: none;
    transition: all 0.3s ease;
    border: 2px solid #e0e0e0;
    font-size: 1.5rem;
}

.social-link-icon:hover {
    background: #000000;
    color: #ffffff;
    transform: scale(1.1);
    border-color: #000000;
}

/* Content Section */
.content-section {
    display: flex;
    flex-direction: column;
    gap: 3rem;
}

.hero-content {
    max-width: 600px;
}

.hero-title {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
    color: #000000;
}

.hero-subtitle {
    font-size: 1.3rem;
    font-weight: 500;
    margin-bottom: 1.5rem;
    color: #666666;
}

.hero-description {
    font-size: 1.1rem;
    margin-bottom: 2rem;
    color: #333333;
    line-height: 1.8;
}

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

.btn {
    padding: 12px 24px;
    border-radius: 4px;
    text-decoration: none;
    font-weight: 500;
    transition: all 0.3s ease;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    border: 1px solid transparent;
}

.btn-primary {
    background: #000000;
    color: #ffffff;
}

.btn-primary:hover {
    background: #333333;
    transform: translateY(-2px);
}

.btn-secondary {
    background: transparent;
    color: #000000;
    border: 1px solid #000000;
}

.btn-secondary:hover {
    background: #000000;
    color: #ffffff;
    transform: translateY(-2px);
}

/* Quick Links */
.quick-links {
    margin-top: 2rem;
}

.quick-links h3 {
    margin-bottom: 1.5rem;
    color: #000000;
}

.links-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1rem;
}

.quick-link {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1rem;
    background: #f8f8f8;
    border: 1px solid #e0e0e0;
    border-radius: 4px;
    text-decoration: none;
    color: #000000;
    transition: all 0.3s ease;
}

.quick-link:hover {
    background: #000000;
    color: #ffffff;
    transform: translateY(-2px);
}

.quick-link i {
    font-size: 1.2rem;
    width: 20px;
    text-align: center;
}

.regular-link {
    color: black;
}

/* Section Styles */
section {
    padding: 4rem 0;
}

.section-title {
    text-align: center;
    margin-bottom: 3rem;
    color: #000000;
    position: relative;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 2px;
    background: #000000;
}

/* About Section */
.about-section {
    padding: 2rem 0;
}

.about-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    width: 100%;
}

.about-text {
    max-width: 650px;
    width: 100%;
    margin: 0 auto;
}

.about-text p {
    font-size: 1.1rem;
    line-height: 1.8;
    margin-bottom: 1.5rem;
    color: #333333;
}

.about-intro {
    font-size: 1.2rem;
    font-weight: 500;
    color: #000000;
}

.research-interests,
.current-work {
    margin-top: 2rem;
}

.research-interests h3,
.current-work h3 {
    color: #000000;
    margin-bottom: 1rem;
    border-bottom: 1px solid #e0e0e0;
    padding-bottom: 0.5rem;
}

.research-interests ul {
    list-style: none;
    margin: 0;
    padding: 0;
}

.research-interests li {
    padding: 0.5rem 0;
    color: #333333;
    position: relative;
    padding-left: 1.5rem;
    line-height: 1.6;
}

/* General list styling for circular bullet points (excluding research interests and navigation) */
ul:not(.research-interests ul):not(.nav-menu) {
    list-style: none;
    padding-left: 0;
}

ul:not(.research-interests ul):not(.nav-menu) li {
    position: relative;
    padding-left: 1.5rem;
    margin-bottom: 0.5rem;
    line-height: 1.6;
}

ul:not(.research-interests ul):not(.nav-menu) li::before {
    content: '•';
    position: absolute;
    left: 0;
    color: #000000;
    font-size: 0.8em;
    top: 0.2em;
}

.research-interests li::before {
    content: '▸';
    position: absolute;
    left: 0;
    color: #000000;
    font-weight: bold;
    font-size: 0.9em;
    top: 0.6em;
}

.about-stats {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.stat-item {
    text-align: center;
    padding: 1.5rem;
    background: #f8f8f8;
    border: 1px solid #e0e0e0;
    border-radius: 4px;
    transition: transform 0.3s ease;
}

.stat-item:hover {
    transform: translateY(-3px);
    border-color: #000000;
}

.stat-item h3 {
    font-size: 2rem;
    color: #000000;
    margin-bottom: 0.5rem;
}

.stat-item p {
    color: #666666;
    font-weight: 500;
    margin-bottom: 0;
}

/* Publications Section */
.publications-section {
    padding: 2rem 0;
}

.publications-filter {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-bottom: 3rem;
    flex-wrap: wrap;
}

.filter-btn {
    padding: 8px 16px;
    border: 1px solid #000000;
    background: transparent;
    color: #000000;
    border-radius: 4px;
    cursor: pointer;
    transition: all 0.3s ease;
    font-weight: 500;
}

.filter-btn.active,
.filter-btn:hover {
    background: #000000;
    color: #ffffff;
}

.publications-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
    gap: 2rem;
}

.publication-card {
    background: #ffffff;
    padding: 2rem;
    border: 1px solid #e0e0e0;
    border-radius: 4px;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    border-left: 3px solid #000000;
    position: relative;
}

.publication-card .tags {
    position: absolute;
    top: 1.2rem;
    right: 1.2rem;
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
    z-index: 2;
}

.publication-card .field {
    position: static;
    background: #eee;
    color: #222;
    font-size: 0.8rem;
    font-weight: 600;
    padding: 2px 12px;
    border-radius: 12px;
    letter-spacing: 0.5px;
    text-transform: capitalize;
    border: 1px solid #ddd;
    margin-bottom: 0.2rem;
    white-space: nowrap;
}

.publication-card .field-computer-vision {
    background: #e53935;
    color: #fff;
    border: none;
}
.publication-card .field-natural-language-processing {
    background: #8e24aa;
    color: #fff;
    border: none;
}
.publication-card .field-reinforcement-learning {
    background: #748c14;
    color: #fff;
    border: none;
}
.publication-card .field-evaluation {
    background: #1a237e;
    color: #fff;
    border: none;
}
.publication-card .field-interpretability {
    background: #1976d2;
    color: #fff;
    border: none;
}
.publication-card .field-regression-analysis {
    background: #388e3c;
    color: #fff;
    border: none;
}

.publication-year {
    display: inline-block;
    background: #000000;
    color: #ffffff;
    padding: 4px 12px;
    border-radius: 4px;
    font-size: 0.9rem;
    font-weight: 500;
    margin-bottom: 1rem;
}

.publication-title {
    font-size: 1.2rem;
    color: #000000;
    margin-bottom: 0.5rem;
}

.publication-authors {
    color: #666666;
    font-style: italic;
    margin-bottom: 0.5rem;
}

.publication-venue {
    color: #888888;
    font-size: 0.9rem;
    margin-bottom: 1rem;
}

.publication-links {
    display: flex;
    gap: 1rem;
}

.publication-link {
    color: #000000;
    text-decoration: none;
    font-size: 0.9rem;
    transition: color 0.3s ease;
    border-bottom: 1px solid transparent;
}

.publication-link:hover {
    color: #666666;
    border-bottom-color: #666666;
}

/* Projects Section */
.projects-section {
    padding: 2rem 0;
}

.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
    gap: 2rem;
}

.project-card {
    background: #ffffff;
    border: 1px solid #e0e0e0;
    border-radius: 4px;
    overflow: hidden;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.project-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
    border-color: #000000;
}

.project-image {
    height: 200px;
    background: #f8f8f8;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 3rem;
    color: #000000;
    border-bottom: 1px solid #e0e0e0;
}

.project-content {
    padding: 2rem;
}

.project-title {
    color: #000000;
    margin-bottom: 1rem;
}

.project-description {
    color: #333333;
    line-height: 1.6;
    margin-bottom: 1.5rem;
}

.project-tags {
    display: flex;
    gap: 0.5rem;
    margin-bottom: 1.5rem;
    flex-wrap: wrap;
}

.tag {
    background: #f8f8f8;
    color: #000000;
    padding: 4px 12px;
    border-radius: 4px;
    font-size: 0.8rem;
    font-weight: 500;
    border: 1px solid #e0e0e0;
}

.project-link {
    color: #000000;
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s ease;
    border-bottom: 1px solid transparent;
}

.project-link:hover {
    color: #666666;
    border-bottom-color: #666666;
}

/* CV Section */
.cv-section {
    padding: 2rem 0;
}

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

.cv-section-item {
    margin-bottom: 3rem;
}

.cv-section-item h3 {
    color: #000000;
    border-bottom: 2px solid #000000;
    padding-bottom: 0.5rem;
    margin-bottom: 2rem;
}

.cv-item {
    display: grid;
    grid-template-columns: 150px 1fr;
    gap: 2rem;
    margin-bottom: 2rem;
    padding: 1.5rem;
    background: #f8f8f8;
    border: 1px solid #e0e0e0;
    border-radius: 4px;
    transition: transform 0.3s ease;
}

.cv-item:hover {
    transform: translateX(5px);
    border-color: #000000;
}

.cv-year {
    font-weight: 600;
    color: #000000;
    font-size: 0.9rem;
}

.cv-details h4 {
    color: #000000;
    margin-bottom: 0.5rem;
}

.cv-details p {
    color: #333333;
    margin-bottom: 0.25rem;
}

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

.skill-category h4 {
    color: #000000;
    margin-bottom: 1rem;
    border-bottom: 1px solid #e0e0e0;
    padding-bottom: 0.5rem;
}

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

.skill-category li {
    padding: 0.5rem 0;
    color: #333333;
    position: relative;
    padding-left: 1.5rem;
}

.skill-category li::before {
    content: '•';
    position: absolute;
    left: 0;
    color: #000000;
    font-size: 0.8em;
    top: 0.2em;
}

.cv-download {
    text-align: center;
    margin-top: 3rem;
}

/* Contact Section */
.contact-section {
    padding: 2rem 0;
}

.contact-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: start;
}

.contact-info {
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

.contact-item {
    display: flex;
    align-items: flex-start;
    gap: 1rem;
    padding: 1.5rem;
    background: #f8f8f8;
    border: 1px solid #e0e0e0;
    border-radius: 4px;
    transition: transform 0.3s ease;
}

.contact-item:hover {
    transform: translateY(-3px);
    border-color: #000000;
}

.contact-item i {
    font-size: 1.5rem;
    color: #000000;
    margin-top: 0.25rem;
}

.contact-item h4 {
    color: #000000;
    margin-bottom: 0.5rem;
}

.contact-item p {
    color: #333333;
    margin-bottom: 0;
}

.social-links h3 {
    color: #000000;
    margin-bottom: 2rem;
    border-bottom: 1px solid #e0e0e0;
    padding-bottom: 0.5rem;
}

.social-grid {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.social-link {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1rem;
    background: #f8f8f8;
    border: 1px solid #e0e0e0;
    border-radius: 4px;
    text-decoration: none;
    color: #000000;
    transition: all 0.3s ease;
}

.social-link:hover {
    background: #000000;
    color: #ffffff;
    transform: translateY(-2px);
}

.social-link i {
    font-size: 1.2rem;
    width: 20px;
    text-align: center;
}

/* Footer */
.footer {
    background: #000000;
    color: #ffffff;
    text-align: center;
    padding: 2rem 0;
    margin-top: 4rem;
}

.footer-content {
    display: flex;
    justify-content: center;
    align-items: center;
    flex-direction: column;
    gap: 1.5rem;
}

.footer-social-links {
    display: flex;
    gap: 1rem;
    align-items: center;
}

.footer-social-link {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background: #333333;
    border-radius: 50%;
    color: #ffffff;
    text-decoration: none;
    transition: all 0.3s ease;
    font-size: 1.2rem;
}

.footer-social-link:hover {
    background: #ffffff;
    color: #000000;
    transform: scale(1.05);
    opacity: 0.9;
}

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

    .nav-menu {
        position: fixed;
        left: -100%;
        top: 70px;
        flex-direction: column;
        background-color: #ffffff;
        width: 100%;
        text-align: center;
        transition: 0.3s;
        box-shadow: 0 10px 27px rgba(0, 0, 0, 0.1);
        padding: 2rem 0;
        border-top: 1px solid #e0e0e0;
    }

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

    .home-layout {
        grid-template-columns: 1fr;
        gap: 2rem;
        text-align: center;
    }

    .portrait-section {
        position: static;
        order: -1;
    }

    .portrait-placeholder {
        width: 150px;
        height: 150px;
        font-size: 2.5rem;
    }

    .hero-title {
        font-size: 2rem;
    }

    .hero-buttons {
        flex-direction: column;
        align-items: center;
    }

    .links-grid {
        grid-template-columns: 1fr;
    }

    .about-content {
        flex-direction: column;
        align-items: stretch;
    }
    .about-text {
        max-width: 100%;
    }

    .about-stats {
        flex-direction: row;
        justify-content: space-around;
    }

    .stat-item {
        padding: 1rem;
    }

    .stat-item h3 {
        font-size: 1.5rem;
    }

    .publications-grid,
    .projects-grid {
        grid-template-columns: 1fr;
    }

    .cv-item {
        grid-template-columns: 1fr;
        gap: 1rem;
    }

    .contact-content {
        grid-template-columns: 1fr;
        gap: 2rem;
    }

    .social-grid {
        flex-direction: row;
        justify-content: center;
        flex-wrap: wrap;
    }

    .footer-content {
        flex-direction: column;
        text-align: center;
        gap: 1.5rem;
    }

    .publications-filter {
        flex-direction: column;
        align-items: center;
    }

    .filter-btn {
        width: 200px;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }

    .hero-title {
        font-size: 1.8rem;
    }

    .section-title {
        font-size: 1.8rem;
    }

    .portrait-placeholder {
        width: 120px;
        height: 120px;
        font-size: 2rem;
    }

    .news-item {
        flex-direction: column;
        gap: 0.5rem;
    }

    .news-date {
        min-width: auto;
        text-align: left;
        width: fit-content;
    }

    .news-title {
        font-size: 1.3rem;
    }
}

/* Animation Classes */
.fade-in {
    opacity: 0;
    transform: translateY(30px);
    transition: all 0.6s ease;
}

.fade-in.visible {
    opacity: 1;
    transform: translateY(0);
}

/* Wave emoji hover effect */
.wave-emoji {
    position: relative;
    cursor: pointer;
    display: inline-block;
    transition: transform 0.2s ease;
}

.wave-emoji:hover {
    transform: scale(0.7);
}

.wave-emoji::after {
    content: '';
    position: absolute;
    top: -15px;
    left: -10px;
    width: 40px;
    height: 40px;
    background-image: url('assets/images/PartyParrot.gif');
    background-size: contain;
    background-repeat: no-repeat;
    background-position: center;
    opacity: 0;
    transition: opacity 0.3s ease;
    pointer-events: none;
    z-index: 1000;
}

.wave-emoji:hover::after {
    opacity: 1;
}

/* Smooth scrolling for older browsers */
@media (prefers-reduced-motion: no-preference) {
    html {
        scroll-behavior: smooth;
    }
}