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

body {
    font-family: 'Inter', sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #fff;
}

html {
    scroll-behavior: smooth;
}

.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;
    padding: 1rem 0;
    transition: all 0.3s ease;
}

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

.nav-logo h2 {
    color: #2563eb;
    font-weight: 700;
}

.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;
}

.nav-toggle {
    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, #667eea 0%, #764ba2 100%);
    color: white;
    min-height: 100vh;
    display: flex;
    align-items: center;
}

.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;
    margin-bottom: 1rem;
    line-height: 1.2;
}

.highlight {
    color: #fbbf24;
}

.hero-subtitle {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    color: #e5e7eb;
}

.hero-description {
    font-size: 1.1rem;
    margin-bottom: 2rem;
    color: #d1d5db;
    line-height: 1.7;
}

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

.btn {
    padding: 12px 30px;
    border: none;
    border-radius: 8px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s ease;
    cursor: pointer;
    display: inline-block;
}

.btn-primary {
    background-color: #fbbf24;
    color: #1f2937;
}

.btn-primary:hover {
    background-color: #f59e0b;
    transform: translateY(-2px);
}

.btn-secondary {
    background-color: transparent;
    color: white;
    border: 2px solid white;
}

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

.btn-outline {
    background-color: transparent;
    color: white;
    border: 2px solid #fbbf24;
}

.btn-outline:hover {
    background-color: #fbbf24;
    color: #1f2937;
    transform: translateY(-2px);
}

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

.profile-card {
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    border-radius: 20px;
    padding: 2rem;
    text-align: center;
}

.profile-img {
    width: 250px;
    height: 250px;
    margin: 0 auto 1rem;
    border-radius: 50%;
    overflow: hidden;
    border: 4px solid #fbbf24;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.1);
}

.profile-img img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    object-position: center;
}

/* Section Styles */
.section-title {
    text-align: center;
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 3rem;
    color: #1f2937;
}

/* About Section */
.about {
    padding: 80px 0;
    background-color: #f9fafb;
}

.about-content {
    max-width: 800px;
    margin: 0 auto;
    text-align: center;
}

.about-text p {
    font-size: 1.1rem;
    margin-bottom: 1.5rem;
    color: #6b7280;
    line-height: 1.7;
}

.about-stats {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
    margin-top: 3rem;
}

.stat {
    text-align: center;
}

.stat h3 {
    font-size: 2.5rem;
    font-weight: 700;
    color: #2563eb;
    margin-bottom: 0.5rem;
}

.stat p {
    color: #6b7280;
    font-weight: 500;
}

/* Skills Section */
.skills {
    padding: 80px 0;
}

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

.skill-category {
    background: white;
    padding: 2rem;
    border-radius: 12px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.05);
    transition: transform 0.3s ease;
}

.skill-category:hover {
    transform: translateY(-5px);
}

.skill-category h3 {
    font-size: 1.3rem;
    font-weight: 600;
    margin-bottom: 1rem;
    color: #1f2937;
}

.skills-list {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.skill-tag {
    background-color: #eff6ff;
    color: #2563eb;
    padding: 6px 12px;
    border-radius: 20px;
    font-size: 0.9rem;
    font-weight: 500;
}

/* Projects Section */
.projects {
    padding: 80px 0;
    background-color: #f9fafb;
}

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

.project-card {
    background: white;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.05);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

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

.project-image {
    height: 200px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 3rem;
    color: white;
}

.project-content {
    padding: 1.5rem;
}

.project-content h3 {
    font-size: 1.3rem;
    font-weight: 600;
    margin-bottom: 1rem;
    color: #1f2937;
}

.project-content p {
    color: #6b7280;
    margin-bottom: 1rem;
    line-height: 1.6;
}

.project-tech {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-bottom: 1rem;
}

.project-tech span {
    background-color: #eff6ff;
    color: #2563eb;
    padding: 4px 8px;
    border-radius: 12px;
    font-size: 0.8rem;
    font-weight: 500;
}

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

.project-link {
    color: #2563eb;
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s ease;
}

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

/* Contact Section */
.contact {
    padding: 80px 0;
}

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

.contact-info h3 {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 1rem;
    color: #1f2937;
}

.contact-info p {
    color: #6b7280;
    margin-bottom: 2rem;
    line-height: 1.7;
}

.contact-details {
    margin-bottom: 2rem;
}

.contact-item {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 1rem;
    color: #6b7280;
}

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

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

.social-link {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background-color: #2563eb;
    color: white;
    border-radius: 8px;
    text-decoration: none;
    transition: background-color 0.3s ease;
}

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

.contact-form {
    background: #f9fafb;
    padding: 2rem;
    border-radius: 12px;
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 12px;
    border: 1px solid #d1d5db;
    border-radius: 8px;
    font-size: 1rem;
    transition: border-color 0.3s ease;
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: #2563eb;
}

/* Footer */
.footer {
    background-color: #1f2937;
    color: white;
    text-align: center;
    padding: 2rem 0;
}

/* Research Section */
.research {
    padding: 80px 0;
    background-color: #f8fafc;
}

.research-intro {
    text-align: center;
    max-width: 800px;
    margin: 0 auto 3rem;
}

.research-intro p {
    font-size: 1.1rem;
    color: #6b7280;
    line-height: 1.7;
}

.research-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 2rem;
    margin-bottom: 3rem;
}

.research-card {
    background: white;
    border-radius: 12px;
    padding: 2rem;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.05);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    display: flex;
    align-items: flex-start;
    gap: 1.5rem;
}

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

.research-icon {
    flex-shrink: 0;
    width: 60px;
    height: 60px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    color: white;
}

.research-content-card h3 {
    font-size: 1.3rem;
    font-weight: 600;
    margin-bottom: 1rem;
    color: #1f2937;
}

.research-content-card p {
    color: #6b7280;
    margin-bottom: 1rem;
    line-height: 1.6;
}

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

.research-link {
    color: #2563eb;
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s ease;
}

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

.research-topics {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.topic-tag {
    background-color: #e0f2fe;
    color: #0369a1;
    padding: 4px 8px;
    border-radius: 12px;
    font-size: 0.8rem;
    font-weight: 500;
}

.achievements {
    background: white;
    border-radius: 12px;
    padding: 2rem;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.05);
}

.achievements h3 {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 1.5rem;
    color: #1f2937;
    text-align: center;
}

.achievements-list {
    list-style: none;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1rem;
}

.achievements-list li {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1rem;
    background-color: #f8fafc;
    border-radius: 8px;
    color: #374151;
    font-weight: 500;
}

.achievements-list i {
    color: #f59e0b;
    font-size: 1.1rem;
}

/* Custom icons for ResearchGate */
.fab.fa-researchgate::before {
    content: "RG";
    font-family: 'Inter', sans-serif;
    font-weight: 700;
    font-size: 0.8rem;
}

/* Experience Section */
.experience {
    padding: 80px 0;
    background-color: #ffffff;
}

.experience-timeline {
    max-width: 800px;
    margin: 0 auto;
    position: relative;
}

.experience-timeline::before {
    content: '';
    position: absolute;
    left: 30px;
    top: 0;
    bottom: 0;
    width: 2px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
}

.experience-item {
    position: relative;
    margin-bottom: 3rem;
    padding-left: 80px;
}

.experience-item::before {
    content: '';
    position: absolute;
    left: 24px;
    top: 0;
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: #667eea;
    border: 3px solid white;
    box-shadow: 0 0 0 3px #667eea;
}

.experience-date {
    display: inline-block;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 8px 16px;
    border-radius: 20px;
    font-size: 0.9rem;
    font-weight: 600;
    margin-bottom: 1rem;
}

.experience-content h3 {
    font-size: 1.4rem;
    font-weight: 600;
    color: #1f2937;
    margin-bottom: 0.5rem;
}

.experience-content h4 {
    font-size: 1.1rem;
    font-weight: 500;
    color: #2563eb;
    margin-bottom: 1rem;
}

.experience-details {
    list-style: none;
    padding: 0;
}

.experience-details li {
    position: relative;
    padding-left: 1.5rem;
    margin-bottom: 0.8rem;
    color: #6b7280;
    line-height: 1.6;
}

.experience-details li::before {
    content: '▶';
    position: absolute;
    left: 0;
    top: 0;
    color: #2563eb;
    font-size: 0.8rem;
}

/* Certifications Section */
.certifications {
    margin-top: 3rem;
    background: white;
    padding: 2rem;
    border-radius: 12px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.05);
}

.certifications h3 {
    text-align: center;
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 2rem;
    color: #1f2937;
}

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

.cert-item {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1rem;
    background-color: #f8fafc;
    border-radius: 8px;
    transition: transform 0.3s ease;
}

.cert-item:hover {
    transform: translateX(5px);
    background-color: #eff6ff;
}

.cert-item i {
    color: #2563eb;
    font-size: 1.2rem;
    flex-shrink: 0;
}

.cert-item span {
    color: #374151;
    font-weight: 500;
    line-height: 1.4;
}

/* CV Download Section */
.cv-download-section {
    padding: 80px 0;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
}

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

.cv-download-text h2 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    color: white;
}

.cv-download-text p {
    font-size: 1.1rem;
    margin-bottom: 2rem;
    opacity: 0.9;
}

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

.cv-highlight {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.cv-highlight i {
    color: #fbbf24;
    font-size: 1.2rem;
}

.cv-download-action {
    text-align: center;
}

.cv-preview {
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    border-radius: 15px;
    padding: 2rem;
    margin-bottom: 2rem;
    border: 1px solid rgba(255, 255, 255, 0.2);
}

.cv-preview i {
    font-size: 4rem;
    color: #fbbf24;
    margin-bottom: 1rem;
}

.cv-preview span {
    display: block;
    font-weight: 600;
    font-size: 1.1rem;
}

.btn-download {
    background: linear-gradient(45deg, #fbbf24, #f59e0b);
    color: #1f2937;
    padding: 15px 40px;
    font-size: 1.1rem;
    font-weight: 600;
    border-radius: 50px;
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px rgba(251, 191, 36, 0.3);
}

.btn-download:hover {
    transform: translateY(-3px);
    box-shadow: 0 6px 20px rgba(251, 191, 36, 0.4);
}

.btn-download i {
    font-size: 1.2rem;
}

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

    .nav-toggle {
        display: flex;
    }

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

    .hero-title {
        font-size: 2.5rem;
    }

    .hero-buttons {
        justify-content: center;
        flex-wrap: wrap;
    }

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

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

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

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

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

    .cv-download-content {
        grid-template-columns: 1fr;
        gap: 2rem;
        text-align: center;
    }
    
    .cv-download-text h2 {
        font-size: 2rem;
    }
    
    .cv-highlights {
        grid-template-columns: 1fr;
    }
    
    .cv-highlight {
        justify-content: center;
    }
}