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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #fff;
}

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

/* Navigation */
.navbar {
    position: fixed;
    top: 0;
    width: 100%;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    z-index: 1000;
    border-bottom: 1px solid rgba(0, 0, 0, 0.1);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.nav-logo h2 {
    color: #2563eb;
    font-weight: 600;
}

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

.nav-link {
    text-decoration: none;
    color: #333;
    font-weight: 500;
    transition: color 0.3s ease;
}

.nav-link:hover {
    color: #2563eb;
}

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

.bar {
    width: 25px;
    height: 3px;
    background-color: #333;
    margin: 3px 0;
    transition: 0.3s;
}

/* Hero Section */
.hero {
    padding: 120px 0 80px;
    background: linear-gradient(135deg, #f8fafc 0%, #e2e8f0 100%);
}

.hero-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 700;
    color: #1e293b;
    margin-bottom: 1rem;
}

.hero-subtitle {
    font-size: 1.5rem;
    color: #2563eb;
    margin-bottom: 1.5rem;
    font-weight: 500;
}

.hero-description {
    font-size: 1.1rem;
    color: #64748b;
    margin-bottom: 2rem;
    line-height: 1.7;
}

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

.btn {
    padding: 12px 24px;
    border-radius: 8px;
    text-decoration: none;
    font-weight: 500;
    transition: all 0.3s ease;
    display: inline-block;
}

.btn-primary {
    background: #2563eb;
    color: white;
}

.btn-primary:hover {
    background: #1d4ed8;
    transform: translateY(-2px);
}

.btn-secondary {
    background: transparent;
    color: #2563eb;
    border: 2px solid #2563eb;
}

.btn-secondary:hover {
    background: #2563eb;
    color: white;
    transform: translateY(-2px);
}

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

.placeholder-image {
    width: 300px;
    height: 300px;
    border-radius: 50%;
    background: linear-gradient(135deg, #2563eb, #3b82f6);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 8rem;
}

/* Sections */
.section {
    padding: 80px 0;
}

.section-alt {
    background: #f8fafc;
}

.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 1rem;
    color: #1e293b;
}

.section-description {
    text-align: center;
    font-size: 1.1rem;
    color: #64748b;
    margin-bottom: 3rem;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

/* CV Section */
.cv-container {
    display: grid;
    grid-template-columns: 1fr 2fr;
    gap: 3rem;
    margin-top: 2rem;
}

.cv-sidebar {
    background: white;
    padding: 2rem;
    border-radius: 12px;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    height: fit-content;
}

.cv-main {
    background: white;
    padding: 2rem;
    border-radius: 12px;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
}

.cv-section {
    margin-bottom: 2rem;
}

.cv-section h3 {
    font-size: 1.3rem;
    font-weight: 600;
    margin-bottom: 1rem;
    color: #1e293b;
    border-bottom: 2px solid #2563eb;
    padding-bottom: 0.5rem;
}

.contact-item {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin-bottom: 0.5rem;
    color: #64748b;
}

.contact-item i {
    color: #2563eb;
    width: 20px;
}

.skill-item {
    margin-bottom: 1rem;
}

.skill-item span {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
}

.skill-bar {
    height: 8px;
    background: #e2e8f0;
    border-radius: 4px;
    overflow: hidden;
}

.skill-progress {
    height: 100%;
    background: linear-gradient(90deg, #2563eb, #3b82f6);
    border-radius: 4px;
    transition: width 0.3s ease;
}

.timeline-item {
    display: flex;
    gap: 1rem;
    margin-bottom: 1.5rem;
}

.timeline-date {
    font-weight: 600;
    color: #2563eb;
    min-width: 120px;
}

.timeline-content h4 {
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: #1e293b;
}

.timeline-content p {
    color: #64748b;
    margin-bottom: 0.5rem;
}

.publication-item {
    margin-bottom: 1rem;
}

.publication-item h4 {
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: #1e293b;
}

.publication-item p {
    color: #64748b;
}

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

.design-item {
    background: white;
    border-radius: 12px;
    padding: 2rem;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.design-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.1);
}

.design-image {
    width: 80px;
    height: 80px;
    border-radius: 12px;
    background: linear-gradient(135deg, #2563eb, #3b82f6);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 2rem;
    margin-bottom: 1.5rem;
}

.design-content h3 {
    font-weight: 600;
    margin-bottom: 1rem;
    color: #1e293b;
}

.design-content p {
    color: #64748b;
    margin-bottom: 1.5rem;
}

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

.tag {
    background: #e2e8f0;
    color: #475569;
    padding: 0.25rem 0.75rem;
    border-radius: 20px;
    font-size: 0.875rem;
    font-weight: 500;
}

/* Research Section */
.research-grid {
    display: grid;
    gap: 2rem;
}

.research-item {
    background: white;
    border-radius: 12px;
    padding: 2rem;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.research-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.1);
}

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

.research-header h3 {
    font-weight: 600;
    color: #1e293b;
    flex: 1;
}

.research-status {
    padding: 0.25rem 0.75rem;
    border-radius: 20px;
    font-size: 0.875rem;
    font-weight: 500;
    margin-left: 1rem;
}

.research-status:contains("Ongoing") {
    background: #fef3c7;
    color: #92400e;
}

.research-status:contains("Published") {
    background: #d1fae5;
    color: #065f46;
}

.research-status:contains("In Review") {
    background: #dbeafe;
    color: #1e40af;
}

.research-description {
    color: #64748b;
    margin-bottom: 1.5rem;
    line-height: 1.7;
}

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

.research-link {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    color: #2563eb;
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s ease;
}

.research-link:hover {
    color: #1d4ed8;
}

/* Data Section */
.data-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(500px, 1fr));
    gap: 3rem;
}

.data-category h3 {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 1.5rem;
    color: #1e293b;
}

.data-items {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.data-item {
    background: white;
    border-radius: 12px;
    padding: 1.5rem;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    display: flex;
    align-items: flex-start;
    gap: 1rem;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.data-item:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 20px -5px rgba(0, 0, 0, 0.1);
}

.data-icon {
    width: 60px;
    height: 60px;
    border-radius: 8px;
    background: linear-gradient(135deg, #2563eb, #3b82f6);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 1.5rem;
    flex-shrink: 0;
}

.data-content h4 {
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: #1e293b;
}

.data-content p {
    color: #64748b;
    margin-bottom: 1rem;
}

.data-meta {
    display: flex;
    gap: 1rem;
}

.data-size,
.data-format,
.data-lang,
.data-license {
    font-size: 0.875rem;
    padding: 0.25rem 0.75rem;
    border-radius: 20px;
    font-weight: 500;
}

.data-size {
    background: #fef3c7;
    color: #92400e;
}

.data-format {
    background: #e0e7ff;
    color: #3730a3;
}

.data-lang {
    background: #d1fae5;
    color: #065f46;
}

.data-license {
    background: #fce7f3;
    color: #9d174d;
}

/* Footer */
.footer {
    background: #1e293b;
    color: white;
    padding: 3rem 0 1rem;
}

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

.footer-section h4 {
    font-weight: 600;
    margin-bottom: 1rem;
    color: white;
}

.footer-section p {
    color: #94a3b8;
    margin-bottom: 1rem;
}

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

.social-link {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background: #334155;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    text-decoration: none;
    transition: background 0.3s ease;
}

.social-link:hover {
    background: #2563eb;
}

.footer-links {
    list-style: none;
}

.footer-links li {
    margin-bottom: 0.5rem;
}

.footer-links a {
    color: #94a3b8;
    text-decoration: none;
    transition: color 0.3s ease;
}

.footer-links a:hover {
    color: white;
}

.footer-bottom {
    border-top: 1px solid #334155;
    padding-top: 1rem;
    text-align: center;
    color: #94a3b8;
}

/* Responsive Design */
@media (max-width: 768px) {
    .hamburger {
        display: flex;
    }
    
    .nav-menu {
        position: fixed;
        left: -100%;
        top: 70px;
        flex-direction: column;
        background-color: white;
        width: 100%;
        text-align: center;
        transition: 0.3s;
        box-shadow: 0 10px 27px rgba(0, 0, 0, 0.05);
        padding: 2rem 0;
    }
    
    .nav-menu.active {
        left: 0;
    }
    
    .hero-container {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .hero-title {
        font-size: 2.5rem;
    }
    
    .cv-container {
        grid-template-columns: 1fr;
    }
    
    .design-grid {
        grid-template-columns: 1fr;
    }
    
    .data-grid {
        grid-template-columns: 1fr;
    }
    
    .research-header {
        flex-direction: column;
        align-items: flex-start;
    }
    
    .research-status {
        margin-left: 0;
        margin-top: 0.5rem;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 2rem;
    }
    
    .section-title {
        font-size: 2rem;
    }
    
    .hero-buttons {
        flex-direction: column;
        align-items: center;
    }
    
    .btn {
        width: 100%;
        max-width: 200px;
        text-align: center;
    }
}

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

/* Loading animations */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.section {
    animation: fadeInUp 0.6s ease-out;
}