:root {
    --bg-primary: #0f0f0f;
    --bg-secondary: #1a1a1a;
    --bg-card: #1f1f1f;
    --text-primary: #ffffff;
    --text-secondary: #888888;
    --accent: #00d4ff;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
}

.bg-animation {
    display: none;
}

/* Navigation */
nav {
    position: fixed;
    top: 0;
    width: 100%;
    background: rgba(10, 10, 15, 0.9);
    backdrop-filter: blur(20px);
    z-index: 1000;
    padding: 1rem 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-family: 'Space Grotesk', sans-serif;
    font-size: 1.3rem;
    font-weight: 700;
    color: var(--text-primary);
    letter-spacing: -0.5px;
}

.logo span {
    color: var(--accent);
}

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

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

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

.menu-toggle {
    display: none;
    flex-direction: column;
    cursor: pointer;
    gap: 5px;
}

.menu-toggle span {
    width: 25px;
    height: 2px;
    background: var(--text-primary);
}

/* Sections */
section {
    min-height: 100vh;
    padding: 100px 2rem;
    display: flex;
    align-items: center;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    width: 100%;
}

/* Hero Section */
#hero {
    padding-top: 120px;
}

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

.hero-text h1 {
    font-size: 3.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
    line-height: 1.2;
}

.hero-text h1 span {
    color: var(--accent);
}

.hero-text .subtitle {
    font-size: 1.5rem;
    color: var(--accent);
    margin-bottom: 1.5rem;
    font-family: 'JetBrains Mono', monospace;
}

.hero-text p {
    color: var(--text-secondary);
    font-size: 1.1rem;
    margin-bottom: 2rem;
    max-width: 500px;
}

.research-interests {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-bottom: 2rem;
}

.tag {
    background: transparent;
    border: 1px solid #333;
    padding: 0.4rem 0.8rem;
    border-radius: 4px;
    font-size: 0.8rem;
    color: var(--text-secondary);
    transition: all 0.3s ease;
}

.tag:hover {
    border-color: var(--accent);
    color: var(--accent);
}

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

.social-links a {
    width: 45px;
    height: 45px;
    border-radius: 50%;
    background: var(--bg-card);
    border: 1px solid rgba(255, 255, 255, 0.1);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-secondary);
    text-decoration: none;
    transition: all 0.3s ease;
}

.social-links a:hover {
    border-color: var(--accent);
    color: var(--accent);
}

.hero-image img {
    width: 100%;
    max-width: 400px;
    border-radius: 20px;
    border: 2px solid rgba(255, 255, 255, 0.1);
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.5);
}

/* Section Header */
.section-header {
    text-align: center;
    margin-bottom: 4rem;
}

.section-header h2 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
    position: relative;
    display: inline-block;
}

.section-header h2::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    width: 40px;
    height: 2px;
    background: var(--accent);
}

.section-header p {
    color: var(--text-secondary);
    font-size: 1.1rem;
}

/* Education Section */
.education-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 2rem;
}

.edu-card {
    background: var(--bg-card);
    border: 1px solid rgba(255, 255, 255, 0.05);
    border-radius: 16px;
    padding: 2rem;
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.edu-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 2px;
    background: var(--accent);
}

.edu-card:hover {
    border-color: var(--accent);
}

.edu-card h3 {
    font-size: 1.3rem;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
}

.edu-card .institution {
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.edu-card .date {
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin-bottom: 1rem;
    font-family: 'JetBrains Mono', monospace;
}

.edu-card .dissertation {
    font-size: 0.9rem;
    color: var(--text-secondary);
    padding-top: 1rem;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}

/* Experience Section */
.timeline {
    position: relative;
    padding-left: 30px;
}

.timeline::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    height: 100%;
    width: 1px;
    background: #333;
}

.timeline-item {
    position: relative;
    padding-bottom: 3rem;
}

.timeline-item::before {
    content: '';
    position: absolute;
    left: -34px;
    top: 5px;
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--accent);
}

.timeline-item:last-child {
    padding-bottom: 0;
}

.exp-card {
    background: var(--bg-card);
    border: none;
    border-radius: 16px;
    padding: 2rem;
    margin-left: 1rem;
}

.exp-card h3 {
    font-size: 1.3rem;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
}

.exp-card .company {
    font-weight: 600;
    margin-bottom: 0.25rem;
}

.exp-card .date {
    color: var(--text-secondary);
    font-size: 0.9rem;
    font-family: 'JetBrains Mono', monospace;
    margin-bottom: 1rem;
}

.exp-card ul {
    list-style: none;
    padding: 0;
}

.exp-card li {
    color: var(--text-secondary);
    padding: 0.5rem 0;
    padding-left: 1.5rem;
    position: relative;
}

.exp-card li::before {
    content: '•';
    color: var(--accent);
    position: absolute;
    left: 0;
}

/* Research Section */
.research-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1.5rem;
}

.research-card {
    background: var(--bg-card);
    border: 1px solid rgba(255, 255, 255, 0.05);
    border-radius: 16px;
    padding: 1.5rem;
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.research-card::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    width: 2px;
    height: 100%;
    background: var(--accent);
}

.research-card:hover {
    border-color: var(--accent);
}

.research-card h3 {
    font-size: 1.1rem;
    margin-bottom: 1rem;
    color: var(--text-primary);
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.research-card h3 i {
    font-size: 1rem;
}

.research-card p {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

/* Skills Section */
.skills-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
}

.skill-category {
    background: var(--bg-card);
    border: 1px solid rgba(255, 255, 255, 0.05);
    border-radius: 16px;
    padding: 2rem;
    transition: all 0.3s ease;
}

.skill-category:hover {
    border-color: var(--accent);
}

.skill-category h3 {
    font-size: 1rem;
    color: var(--text-primary);
    margin-bottom: 1.5rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.skill-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.skill-tag {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.1);
    padding: 0.4rem 0.8rem;
    border-radius: 6px;
    font-size: 0.85rem;
    color: var(--text-secondary);
    transition: all 0.3s ease;
}

.skill-tag:hover {
    border-color: var(--accent);
    color: var(--accent);
}

/* Footer */
footer {
    background: var(--bg-secondary);
    padding: 2rem;
    text-align: center;
    border-top: 1px solid rgba(255, 255, 255, 0.05);
}

footer p {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

footer a {
    color: var(--accent);
    text-decoration: none;
}

/* Responsive */
@media (max-width: 968px) {
    .hero-content {
        grid-template-columns: 1fr;
        text-align: center;
    }

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

    .hero-text p {
        max-width: 100%;
    }

    .research-interests,
    .social-links {
        justify-content: center;
    }

    .hero-image {
        order: -1;
    }

    .hero-image img {
        max-width: 300px;
    }

    .nav-links {
        display: none;
    }

    .menu-toggle {
        display: flex;
    }
}

@media (max-width: 600px) {
    .hero-text h1 {
        font-size: 2rem;
    }

    .hero-text .subtitle {
        font-size: 1.2rem;
    }

    section {
        padding: 80px 1rem;
    }

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