/* CSS Variables for Theme Support */
:root {
    /* Light Theme Colors */
    --primary-color: #2563eb;
    --secondary-color: #1e40af;
    --accent-color: #3b82f6;
    --text-primary: #1f2937;
    --text-secondary: #6b7280;
    --text-muted: #9ca3af;
    --bg-primary: #ffffff;
    --bg-secondary: #f9fafb;
    --bg-tertiary: #f3f4f6;
    --border-color: #e5e7eb;
    --shadow-light: 0 1px 3px rgba(0, 0, 0, 0.1);
    --shadow-medium: 0 4px 6px rgba(0, 0, 0, 0.1);
    --shadow-heavy: 0 10px 25px rgba(0, 0, 0, 0.1);
    --gradient-primary: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --gradient-secondary: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
}

/* Dark Theme Colors */
[data-theme="dark"] {
    --primary-color: #3b82f6;
    --secondary-color: #60a5fa;
    --accent-color: #93c5fd;
    --text-primary: #f9fafb;
    --text-secondary: #d1d5db;
    --text-muted: #9ca3af;
    --bg-primary: #111827;
    --bg-secondary: #1f2937;
    --bg-tertiary: #374151;
    --border-color: #4b5563;
    --shadow-light: 0 1px 3px rgba(0, 0, 0, 0.3);
    --shadow-medium: 0 4px 6px rgba(0, 0, 0, 0.3);
    --shadow-heavy: 0 10px 25px rgba(0, 0, 0, 0.3);
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    background-color: var(--bg-primary);
    transition: background-color 0.3s ease, color 0.3s ease;
}

.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;
}

.section-title {
    font-size: 2.5rem;
    text-align: center;
    margin-bottom: 3rem;
    position: relative;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 4px;
    background: var(--gradient-primary);
    border-radius: 2px;
}

/* Header */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
    z-index: 1000;
    transition: all 0.3s ease;
}

[data-theme="dark"] .header {
    background: rgba(17, 24, 39, 0.95);
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 0;
}

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
}

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

.nav-link {
    text-decoration: none;
    color: var(--text-primary);
    font-weight: 500;
    transition: color 0.3s ease;
    position: relative;
}

.nav-link:hover {
    color: var(--primary-color);
}

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

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

.nav-link.active {
    color: var(--primary-color);
}

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

.theme-toggle {
    background: none;
    border: none;
    font-size: 1.2rem;
    color: var(--text-primary);
    cursor: pointer;
    padding: 0.5rem;
    border-radius: 50%;
    transition: all 0.3s ease;
}

.theme-toggle:hover {
    background: var(--bg-secondary);
    color: var(--primary-color);
}

.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    background: none;
    border: none;
    cursor: pointer;
    padding: 0.5rem;
}

.mobile-menu-toggle span {
    width: 25px;
    height: 3px;
    background: var(--text-primary);
    margin: 3px 0;
    transition: 0.3s;
    border-radius: 2px;
}

/* Hero Section */
.hero {
    padding: 120px 0 80px;
    background: var(--gradient-primary);
    color: white;
    text-align: center;
}

.hero-title {
    font-size: 3.5rem;
    margin-bottom: 1.5rem;
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.greeting {
    font-size: 1.5rem;
    font-weight: 400;
    opacity: 0.9;
}

.name {
    font-size: 4rem;
    font-weight: 700;
}

.title {
    font-size: 2rem;
    font-weight: 500;
    opacity: 0.9;
}

.hero-subtitle {
    font-size: 1.25rem;
    margin-bottom: 2rem;
    opacity: 0.9;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

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

.btn {
    padding: 12px 24px;
    border: none;
    border-radius: 8px;
    font-weight: 600;
    text-decoration: none;
    transition: all 0.3s ease;
    cursor: pointer;
    display: inline-block;
}

.btn-primary {
    background: white;
    color: var(--primary-color);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-medium);
}

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

.btn-secondary:hover {
    background: white;
    color: var(--primary-color);
    transform: translateY(-2px);
}

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

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

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

.about-description {
    font-size: 1.1rem;
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
    line-height: 1.8;
}

.about-highlights {
    display: flex;
    justify-content: center;
    gap: 2rem;
    margin-top: 2rem;
    flex-wrap: wrap;
}

.highlight-item {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-weight: 600;
    color: var(--primary-color);
}

.highlight-item i {
    font-size: 1.2rem;
}

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

.project-card {
    background: var(--bg-primary);
    border-radius: 12px;
    overflow: hidden;
    box-shadow: var(--shadow-light);
    transition: all 0.3s ease;
    border: 1px solid var(--border-color);
}

.project-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-heavy);
}

.project-image {
    height: 200px;
    background: var(--gradient-secondary);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 3rem;
    color: white;
}

.project-content {
    padding: 1.5rem;
}

.project-title {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.project-description {
    color: var(--text-secondary);
    margin-bottom: 1rem;
    line-height: 1.6;
}

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

.tag {
    background: var(--bg-tertiary);
    color: var(--text-secondary);
    padding: 0.25rem 0.75rem;
    border-radius: 20px;
    font-size: 0.875rem;
    font-weight: 500;
}

.project-btn {
    background: var(--primary-color);
    color: white;
    border: none;
    padding: 0.75rem 1.5rem;
    border-radius: 6px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
}

.project-btn:hover {
    background: var(--secondary-color);
    transform: translateY(-2px);
}

/* Skills Section */
.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin-top: 2rem;
}

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

.skill-category:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-medium);
}

.skill-category-title {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-size: 1.25rem;
    margin-bottom: 1.5rem;
    color: var(--primary-color);
}

.skill-category-title i {
    font-size: 1.5rem;
}

.skill-items {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
}

.skill-item {
    background: var(--bg-tertiary);
    color: var(--text-secondary);
    padding: 0.5rem 1rem;
    border-radius: 6px;
    font-size: 0.9rem;
    font-weight: 500;
    transition: all 0.3s ease;
}

.skill-item:hover {
    background: var(--primary-color);
    color: white;
    transform: translateY(-2px);
}

/* Certifications Section */
.certifications-section {
    background: var(--bg-secondary);
}

.certifications-content {
    max-width: 1200px;
    margin: 0 auto;
}

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

.certification-card {
    background: var(--bg-primary);
    border-radius: 12px;
    overflow: hidden;
    box-shadow: var(--shadow-light);
    border: 1px solid var(--border-color);
    transition: all 0.3s ease;
}

.certification-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-heavy);
}

.certification-header {
    background: var(--gradient-primary);
    color: white;
    padding: 1.5rem;
    text-align: center;
}

.certification-header i {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    display: block;
}

.certification-header h3 {
    font-size: 1.25rem;
    margin: 0;
    line-height: 1.3;
}

.certification-body {
    padding: 1.5rem;
}

.certification-image {
    margin-bottom: 1.5rem;
    text-align: center;
}

.certificate-img {
    max-width: 100%;
    height: auto;
    border-radius: 8px;
    box-shadow: var(--shadow-light);
    border: 1px solid var(--border-color);
    transition: transform 0.3s ease;
    cursor: pointer;
}

.certificate-img:hover {
    transform: scale(1.05);
    box-shadow: var(--shadow-medium);
}

.certificate-placeholder {
    background: var(--bg-tertiary);
    border: 2px dashed var(--border-color);
    border-radius: 8px;
    padding: 2rem;
    text-align: center;
    color: var(--text-muted);
    min-height: 200px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 1rem;
}

.certificate-placeholder i {
    font-size: 3rem;
    color: var(--text-muted);
}

.certificate-placeholder p {
    font-weight: 600;
    margin: 0;
    color: var(--text-secondary);
}

.certificate-placeholder small {
    font-size: 0.875rem;
    color: var(--text-muted);
}

.certification-description {
    color: var(--text-secondary);
    line-height: 1.6;
    margin-bottom: 1.5rem;
    text-align: left;
}

.certification-details {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-top: 1rem;
    border-top: 1px solid var(--border-color);
}

.certification-issuer {
    font-weight: 600;
    color: var(--primary-color);
    font-size: 0.9rem;
}

.certification-date {
    background: var(--bg-tertiary);
    color: var(--text-secondary);
    padding: 0.25rem 0.75rem;
    border-radius: 20px;
    font-size: 0.875rem;
    font-weight: 500;
}

/* Contact Section */
.contact-content {
    max-width: 600px;
    margin: 0 auto;
}

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

.contact-item {
    display: flex;
    align-items: center;
    gap: 1.5rem;
    padding: 1.5rem;
    background: var(--bg-primary);
    border-radius: 12px;
    box-shadow: var(--shadow-light);
    border: 1px solid var(--border-color);
    transition: all 0.3s ease;
}

.contact-item:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-medium);
}

.contact-item i {
    font-size: 2rem;
    color: var(--primary-color);
    width: 50px;
    text-align: center;
}

.contact-details h3 {
    margin-bottom: 0.5rem;
    color: var(--text-primary);
}

.contact-details a {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s ease;
}

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

/* Footer */
.footer {
    background: var(--bg-secondary);
    padding: 2rem 0;
    text-align: center;
    border-top: 1px solid var(--border-color);
}

.footer p {
    color: var(--text-secondary);
}

/* Modal */
.modal {
    display: none;
    position: fixed;
    z-index: 2000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    backdrop-filter: blur(5px);
}

.modal-content {
    background-color: var(--bg-primary);
    margin: 5% auto;
    padding: 2rem;
    border-radius: 12px;
    width: 90%;
    max-width: 600px;
    position: relative;
    box-shadow: var(--shadow-heavy);
}

.modal-close {
    color: var(--text-muted);
    float: right;
    font-size: 2rem;
    font-weight: bold;
    cursor: pointer;
    transition: color 0.3s ease;
}

.modal-close:hover {
    color: var(--text-primary);
}

.modal-body h2 {
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.modal-body p {
    color: var(--text-secondary);
    line-height: 1.6;
    margin-bottom: 1rem;
}

/* Responsive Design */
@media (max-width: 768px) {
    .nav {
        display: none;
    }
    
    .mobile-menu-toggle {
        display: flex;
    }
    
    .hero-title {
        font-size: 2.5rem;
    }
    
    .name {
        font-size: 3rem;
    }
    
    .title {
        font-size: 1.5rem;
    }
    
    .hero-cta {
        flex-direction: column;
        align-items: center;
    }
    
    .section-title {
        font-size: 2rem;
    }
    
    .projects-grid {
        grid-template-columns: 1fr;
    }
    
    .skills-grid {
        grid-template-columns: 1fr;
    }
    
    .about-highlights {
        flex-direction: column;
        align-items: center;
    }
    
    .contact-item {
        flex-direction: column;
        text-align: center;
    }
    
    .certifications-grid {
        grid-template-columns: 1fr;
    }
    
    .modal-content {
        margin: 10% auto;
        width: 95%;
        padding: 1.5rem;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }
    
    .hero {
        padding: 100px 0 60px;
    }
    
    .hero-title {
        font-size: 2rem;
    }
    
    .name {
        font-size: 2.5rem;
    }
    
    .section {
        padding: 60px 0;
    }
    
    .project-card {
        margin: 0 10px;
    }
}

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

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

/* Smooth transitions for theme switching */
* {
    transition: background-color 0.3s ease, color 0.3s ease, border-color 0.3s ease;
}