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

:root {
    --bg-primary: #0a0a0a;
    --bg-secondary: #111111;
    --bg-card: #1a1a1a;
    --text-primary: #ffffff;
    --text-secondary: #a0a0a0;
    --accent-primary: #3b82f6;
    --accent-secondary: #8b5cf6;
    --border-color: #2a2a2a;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    background-color: var(--bg-primary);
}

.container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Navigation */
nav {
    background: rgba(10, 10, 10, 0.8);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
    position: sticky;
    top: 0;
    z-index: 100;
}

.nav-container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 1rem 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

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

.nav-links a {
    text-decoration: none;
    color: var(--text-secondary);
    font-weight: 500;
    transition: color 0.3s;
}

.nav-links a:hover {
    color: var(--accent-primary);
}

/* Hero Section */
.hero {
    background: var(--bg-primary);
    color: var(--text-primary);
    padding: 8rem 20px 6rem;
    text-align: center;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 800px;
    height: 800px;
    background: radial-gradient(circle, rgba(59, 130, 246, 0.1) 0%, transparent 70%);
    pointer-events: none;
}

.hero-content {
    position: relative;
    z-index: 1;
}

.profile-image {
    width: 180px;
    height: 180px;
    border-radius: 50%;
    object-fit: cover;
    margin-bottom: 1.5rem;
    border: 4px solid var(--accent-primary);
    box-shadow: 0 8px 30px rgba(59, 130, 246, 0.3);
}

.hero-content h1 {
    font-size: 3.5rem;
    margin-bottom: 0.5rem;
    font-weight: 800;
    background: linear-gradient(135deg, var(--text-primary) 0%, var(--text-secondary) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-content h2 {
    font-size: 1.5rem;
    font-weight: 400;
    color: var(--text-secondary);
    margin-bottom: 1rem;
}

.location {
    font-size: 1.1rem;
    margin-bottom: 2.5rem;
    color: var(--text-secondary);
}

.hero-links {
    display: flex;
    gap: 1rem;
    justify-content: center;
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 0.875rem 2rem;
    background: var(--accent-primary);
    color: var(--text-primary);
    text-decoration: none;
    border-radius: 8px;
    font-weight: 600;
    transition: all 0.3s;
    border: 2px solid transparent;
}

.btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 20px rgba(59, 130, 246, 0.3);
}

.btn-secondary {
    background: transparent;
    color: var(--text-primary);
    border: 2px solid var(--border-color);
}

.btn-secondary:hover {
    background: var(--bg-card);
    border-color: var(--accent-primary);
    box-shadow: 0 8px 20px rgba(59, 130, 246, 0.2);
}

/* Sections */
.section {
    padding: 5rem 20px;
    background: var(--bg-primary);
}

.section-alt {
    background: var(--bg-secondary);
}

.section h2 {
    font-size: 2.5rem;
    margin-bottom: 3rem;
    color: var(--text-primary);
    font-weight: 700;
    text-align: center;
}

.section h3 {
    font-size: 1.8rem;
    margin: 3rem 0 1.5rem;
    color: var(--text-primary);
}

.intro {
    font-size: 1.15rem;
    margin-bottom: 1.5rem;
    line-height: 1.8;
    color: var(--text-secondary);
}

.about-content {
    display: grid;
    grid-template-columns: 300px 1fr;
    gap: 3rem;
    align-items: start;
    margin-bottom: 3rem;
}

.about-image {
    width: 100%;
    border-radius: 12px;
    box-shadow: 0 8px 30px rgba(0, 0, 0, 0.3);
    border: 2px solid var(--border-color);
}

.about-text {
    max-width: 800px;
}

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

.skill-category {
    background: var(--bg-card);
    padding: 2rem;
    border-radius: 12px;
    border: 1px solid var(--border-color);
    transition: all 0.3s;
}

.skill-category:hover {
    border-color: var(--accent-primary);
    transform: translateY(-4px);
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.3);
}

.skill-category h4 {
    color: var(--accent-primary);
    margin-bottom: 1.5rem;
    font-size: 1.3rem;
    font-weight: 600;
}

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

.skill-category li {
    padding: 0.75rem 0;
    border-bottom: 1px solid var(--border-color);
    color: var(--text-secondary);
    transition: color 0.3s;
}

.skill-category li:hover {
    color: var(--text-primary);
}

.skill-category li:last-child {
    border-bottom: none;
}

/* Experience */
.experience-item {
    background: var(--bg-card);
    padding: 2.5rem;
    margin-bottom: 2rem;
    border-radius: 12px;
    border: 1px solid var(--border-color);
    transition: all 0.3s;
}

.experience-item:hover {
    border-color: var(--accent-primary);
    transform: translateY(-2px);
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.3);
}

.experience-header {
    display: flex;
    justify-content: space-between;
    align-items: baseline;
    margin-bottom: 0.5rem;
    flex-wrap: wrap;
    gap: 1rem;
}

.experience-item h3 {
    color: var(--text-primary);
    margin: 0;
    font-size: 1.5rem;
    font-weight: 600;
}

.experience-item h4 {
    color: var(--accent-primary);
    font-weight: 600;
    margin-bottom: 1.5rem;
    font-size: 1.1rem;
}

.highlight-project {
    background: linear-gradient(135deg, rgba(59, 130, 246, 0.1), rgba(139, 92, 246, 0.1));
    border: 2px solid var(--accent-primary);
    border-radius: 8px;
    padding: 1.5rem;
    margin: 1.5rem 0;
}

.highlight-project h5 {
    color: var(--accent-primary);
    font-size: 1.2rem;
    margin: 0 0 1rem 0;
    font-weight: 600;
}

.highlight-project p {
    color: var(--text-secondary);
    margin-bottom: 1rem;
    line-height: 1.7;
}

.highlight-project ul {
    margin: 1rem 0;
    padding-left: 1.5rem;
}

.highlight-project li {
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
    line-height: 1.6;
}

.project-links {
    display: flex;
    gap: 1rem;
    margin-top: 1rem;
    flex-wrap: wrap;
}

.project-links .btn {
    font-size: 0.9rem;
    padding: 0.625rem 1.25rem;
}

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

.experience-item ul {
    margin: 1.5rem 0;
    padding-left: 1.5rem;
}

.experience-item li {
    margin-bottom: 0.75rem;
    color: var(--text-secondary);
    line-height: 1.6;
}

.tech-stack {
    margin-top: 1.5rem;
    padding-top: 1.5rem;
    border-top: 1px solid var(--border-color);
    color: var(--text-secondary);
    font-size: 0.95rem;
}

/* Publications */
.publication-item {
    background: var(--bg-card);
    padding: 2.5rem;
    border-radius: 12px;
    border: 1px solid var(--border-color);
    transition: all 0.3s;
}

.publication-item:hover {
    border-color: var(--accent-primary);
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.3);
}

.publication-item h3 {
    color: var(--text-primary);
    margin: 0 0 1rem 0;
    font-weight: 600;
}

.publication-meta {
    color: var(--text-secondary);
    margin-bottom: 1rem;
    font-style: italic;
}

.publication-description {
    margin-bottom: 1.5rem;
    line-height: 1.8;
    color: var(--text-secondary);
}

.publication-item .btn {
    margin-top: 1rem;
    margin-right: 1rem;
}

/* Contact */
.contact-info {
    font-size: 1.15rem;
    margin-bottom: 2rem;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.contact-info p {
    margin-bottom: 1rem;
    color: var(--text-secondary);
}

.contact-info a {
    color: var(--accent-primary);
    text-decoration: none;
    transition: color 0.3s;
}

.contact-info a:hover {
    color: var(--accent-secondary);
}

.email-reveal {
    background: var(--accent-primary);
    color: var(--text-primary);
    border: none;
    padding: 0.5rem 1rem;
    border-radius: 6px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s;
}

.email-reveal:hover {
    background: var(--accent-secondary);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(59, 130, 246, 0.3);
}

.contact-note {
    font-style: italic;
    color: var(--text-secondary);
    text-align: center;
    margin-top: 2rem;
}

/* Footer */
footer {
    background: var(--bg-secondary);
    color: var(--text-secondary);
    padding: 2rem 20px;
    text-align: center;
    border-top: 1px solid var(--border-color);
}

/* Article Styles */
.article-header {
    background: var(--bg-primary);
    color: var(--text-primary);
    padding: 6rem 20px 4rem;
    text-align: center;
    border-bottom: 1px solid var(--border-color);
}

.article-header h1 {
    font-size: 2.5rem;
    margin-bottom: 1.5rem;
    font-weight: 700;
    max-width: 900px;
    margin-left: auto;
    margin-right: auto;
}

.article-meta {
    font-size: 1.05rem;
    color: var(--text-secondary);
    line-height: 1.8;
}

.article-content {
    max-width: 800px;
    margin: 0 auto;
    padding: 3rem 20px;
    background: var(--bg-primary);
}

.article-content h2 {
    font-size: 2rem;
    margin-top: 3rem;
    margin-bottom: 1.5rem;
    color: var(--text-primary);
    font-weight: 700;
}

.article-content h3 {
    font-size: 1.5rem;
    margin-top: 2.5rem;
    margin-bottom: 1rem;
    color: var(--text-primary);
    font-weight: 600;
}

.article-content p {
    margin-bottom: 1.5rem;
    line-height: 1.8;
    color: var(--text-secondary);
}

.article-content ul, .article-content ol {
    margin-bottom: 1.5rem;
    padding-left: 2rem;
}

.article-content li {
    margin-bottom: 0.75rem;
    color: var(--text-secondary);
    line-height: 1.7;
}

.abstract {
    background: var(--bg-card);
    padding: 2.5rem;
    border-left: 4px solid var(--accent-primary);
    margin: 2rem 0;
    border-radius: 8px;
}

.abstract h2 {
    margin-top: 0;
}

.keywords {
    font-style: italic;
    color: var(--text-secondary);
    margin: 2rem 0;
}

.note-box {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-left: 4px solid var(--accent-secondary);
    padding: 1.5rem;
    border-radius: 8px;
    margin: 2rem 0;
}

.note-box a {
    color: var(--accent-primary);
    text-decoration: none;
    font-weight: 600;
}

.note-box a:hover {
    color: var(--accent-secondary);
    text-decoration: underline;
}

.license-box {
    background: var(--bg-card);
    border: 2px solid var(--accent-primary);
    padding: 2rem;
    border-radius: 8px;
    margin: 2rem 0;
}

.license-box h3 {
    color: var(--accent-primary);
    margin-top: 0;
    margin-bottom: 1rem;
    font-size: 1.3rem;
}

.license-box p {
    margin-bottom: 1rem;
    line-height: 1.8;
}

.license-box a {
    color: var(--accent-primary);
    text-decoration: none;
    font-weight: 600;
}

.license-box a:hover {
    color: var(--accent-secondary);
    text-decoration: underline;
}

.back-link {
    display: inline-block;
    margin-bottom: 2rem;
    color: var(--accent-primary);
    text-decoration: none;
    font-weight: 600;
    transition: color 0.3s;
}

.back-link:hover {
    color: var(--accent-secondary);
}

.references {
    margin-top: 3rem;
    padding-top: 2rem;
    border-top: 2px solid var(--border-color);
}

.references h2 {
    margin-top: 0;
}

.references p {
    margin-bottom: 1.5rem;
    padding-left: 1rem;
    text-indent: -1rem;
    color: var(--text-secondary);
    line-height: 1.7;
}

/* Responsive Design */
@media (max-width: 768px) {
    .hero {
        padding: 5rem 20px 4rem;
    }

    .hero-content h1 {
        font-size: 2.5rem;
    }

    .hero-content h2 {
        font-size: 1.2rem;
    }

    .nav-links {
        gap: 1rem;
        font-size: 0.9rem;
    }

    .section {
        padding: 3rem 20px;
    }

    .section h2 {
        font-size: 2rem;
    }

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

    .experience-header {
        flex-direction: column;
        align-items: flex-start;
    }

    .article-header h1 {
        font-size: 1.8rem;
    }

    .hero-links {
        flex-direction: column;
        gap: 0.75rem;
    }

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

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

    .about-image {
        max-width: 300px;
        margin: 0 auto;
    }
}

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

/* Selection color */
::selection {
    background-color: var(--accent-primary);
    color: var(--text-primary);
}