/* Modern Dark Theme Developer Portfolio CSS */

/* CSS Variables for consistent theming */
:root {
    /* Dark theme colors */
    --bg-primary: #0a0a0a;
    --bg-secondary: #111111;
    --bg-tertiary: #1a1a1a;
    --bg-card: #1e1e1e;
    
    /* Text colors */
    --text-primary: #ffffff;
    --text-secondary: #b3b3b3;
    --text-muted: #666666;
    
    /* Accent colors */
    --accent-primary: #00d4ff;
    --accent-secondary: #ff6b6b;
    --accent-success: #51cf66;
    --accent-warning: #ffd43b;
    
    /* Gradients */
    --gradient-primary: linear-gradient(135deg, #00d4ff 0%, #0099cc 100%);
    --gradient-secondary: linear-gradient(135deg, #ff6b6b 0%, #ee5a24 100%);
    
    /* Shadows */
    --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 8px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 8px 16px rgba(0, 0, 0, 0.5);
    
    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    
    /* Border radius */
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;
    
    /* Transitions */
    --transition-fast: 0.2s ease;
    --transition-normal: 0.3s ease;
    --transition-slow: 0.5s ease;
}

/* 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;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
}

/* Container */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-sm);
}

/* Navigation */
.nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(10, 10, 10, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    z-index: 1000;
    transition: var(--transition-normal);
}

.nav-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--spacing-sm) 0;
    max-width: 1200px;
    margin: 0 auto;
    padding-left: var(--spacing-sm);
    padding-right: var(--spacing-sm);
}

.nav-logo .logo-text {
    font-size: 1.5rem;
    font-weight: 700;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    text-decoration: none;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: var(--spacing-lg);
}

.nav-link {
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 500;
    transition: var(--transition-fast);
    position: relative;
}

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

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--gradient-primary);
    transition: var(--transition-fast);
}

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

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

.nav-toggle .bar {
    width: 25px;
    height: 3px;
    background: var(--text-primary);
    margin: 3px 0;
    transition: var(--transition-fast);
}

/* Main content */
.main {
    margin-top: 80px;
    min-height: calc(100vh - 80px);
}

/* Hero Section */
.hero {
    padding: var(--spacing-xl) 0;
    text-align: center;
    background: radial-gradient(ellipse at center, rgba(0, 212, 255, 0.1) 0%, transparent 70%);
}

.hero-content {
    max-width: 800px;
    margin: 0 auto;
}

.hero-avatar {
    width: 150px;
    height: 150px;
    border-radius: 50%;
    margin: 0 auto var(--spacing-lg);
    border: 4px solid var(--accent-primary);
    box-shadow: var(--shadow-lg);
    transition: var(--transition-normal);
}

.hero-avatar:hover {
    transform: scale(1.05);
    box-shadow: 0 0 30px rgba(0, 212, 255, 0.5);
}

.hero-title {
    font-size: 3rem;
    font-weight: 800;
    margin-bottom: var(--spacing-sm);
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: 1.5rem;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-md);
    font-weight: 300;
}

.hero-description {
    font-size: 1.1rem;
    color: var(--text-muted);
    margin-bottom: var(--spacing-xl);
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.hero-buttons {
    display: flex;
    gap: var(--spacing-md);
    justify-content: center;
    flex-wrap: wrap;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-xs);
    padding: var(--spacing-sm) var(--spacing-lg);
    border: none;
    border-radius: var(--radius-md);
    font-weight: 600;
    text-decoration: none;
    transition: var(--transition-normal);
    cursor: pointer;
    font-size: 1rem;
}

.btn-primary {
    background: var(--gradient-primary);
    color: white;
    box-shadow: var(--shadow-md);
}

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

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

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

/* Section styles */
.section {
    padding: var(--spacing-xl) 0;
}

.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: var(--spacing-xl);
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* Projects Grid */
.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: var(--spacing-lg);
    margin-top: var(--spacing-xl);
}

.project-card {
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    border: 1px solid rgba(255, 255, 255, 0.1);
    transition: var(--transition-normal);
    position: relative;
    overflow: hidden;
}

.project-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: var(--gradient-primary);
}

.project-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg);
    border-color: var(--accent-primary);
}

.project-image {
    width: 100%;
    height: 200px;
    object-fit: cover;
    border-radius: var(--radius-md);
    margin-bottom: var(--spacing-md);
}

.project-title {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: var(--spacing-sm);
    color: var(--text-primary);
}

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

.project-tech {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-xs);
    margin-bottom: var(--spacing-md);
}

.tech-tag {
    background: rgba(0, 212, 255, 0.1);
    color: var(--accent-primary);
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--radius-sm);
    font-size: 0.85rem;
    font-weight: 500;
    border: 1px solid rgba(0, 212, 255, 0.2);
}

.project-links {
    display: flex;
    gap: var(--spacing-sm);
    flex-wrap: wrap;
    margin-top: var(--spacing-md);
}

.project-link {
    color: var(--accent-primary);
    text-decoration: none;
    font-weight: 600;
    transition: var(--transition-fast);
    padding: var(--spacing-xs) var(--spacing-sm);
    border: 1px solid var(--accent-primary);
    border-radius: var(--radius-sm);
    font-size: 0.9rem;
}

.project-link:hover {
    color: var(--text-primary);
    background: var(--accent-primary);
}

/* About Section */
.about-content {
    display: grid;
    grid-template-columns: 1fr 2fr;
    gap: var(--spacing-xl);
    align-items: start;
}

.about-text {
    color: var(--text-secondary);
    line-height: 1.8;
}

.about-text p {
    margin-bottom: var(--spacing-md);
}

.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-lg);
    margin-top: var(--spacing-xl);
}

.skill-category {
    background: var(--bg-card);
    padding: var(--spacing-lg);
    border-radius: var(--radius-lg);
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.skill-category h3 {
    color: var(--accent-primary);
    margin-bottom: var(--spacing-md);
    font-size: 1.2rem;
}

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

.skill-list li {
    color: var(--text-secondary);
    margin-bottom: var(--spacing-xs);
    padding-left: var(--spacing-sm);
    position: relative;
}

.skill-list li::before {
    content: '▸';
    color: var(--accent-primary);
    position: absolute;
    left: 0;
}

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

.form-group {
    margin-bottom: var(--spacing-md);
}

.form-label {
    display: block;
    color: var(--text-primary);
    margin-bottom: var(--spacing-xs);
    font-weight: 500;
}

.form-input,
.form-textarea {
    width: 100%;
    padding: var(--spacing-sm);
    background: var(--bg-card);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: var(--radius-md);
    color: var(--text-primary);
    font-family: inherit;
    transition: var(--transition-fast);
}

.form-input:focus,
.form-textarea:focus {
    outline: none;
    border-color: var(--accent-primary);
    box-shadow: 0 0 0 3px rgba(0, 212, 255, 0.1);
}

.form-textarea {
    resize: vertical;
    min-height: 120px;
}

/* Footer */
.footer {
    background: var(--bg-secondary);
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding: var(--spacing-xl) 0 var(--spacing-md);
    margin-top: var(--spacing-xl);
}

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

.footer-section h3,
.footer-section h4 {
    color: var(--text-primary);
    margin-bottom: var(--spacing-md);
}

.footer-section p {
    color: var(--text-secondary);
    line-height: 1.6;
}

.social-links {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.social-link {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    color: var(--text-secondary);
    text-decoration: none;
    transition: var(--transition-fast);
}

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

.social-link .icon {
    width: 20px;
    height: 20px;
}

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

.footer-links li {
    margin-bottom: var(--spacing-xs);
}

.footer-links a {
    color: var(--text-secondary);
    text-decoration: none;
    transition: var(--transition-fast);
}

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

.footer-bottom {
    text-align: center;
    padding-top: var(--spacing-md);
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    color: var(--text-muted);
}

/* Responsive Design */
@media (max-width: 768px) {
    .nav-menu {
        position: fixed;
        left: -100%;
        top: 70px;
        flex-direction: column;
        background: var(--bg-secondary);
        width: 100%;
        text-align: center;
        transition: var(--transition-normal);
        box-shadow: var(--shadow-lg);
        padding: var(--spacing-lg) 0;
    }

    .nav-menu.active {
        left: 0;
    }

    .nav-toggle {
        display: flex;
    }

    .nav-toggle.active .bar:nth-child(2) {
        opacity: 0;
    }

    .nav-toggle.active .bar:nth-child(1) {
        transform: translateY(8px) rotate(45deg);
    }

    .nav-toggle.active .bar:nth-child(3) {
        transform: translateY(-8px) rotate(-45deg);
    }

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

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

    .hero-buttons {
        flex-direction: column;
        align-items: center;
    }

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

    .about-content {
        grid-template-columns: 1fr;
        gap: var(--spacing-lg);
    }

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

    .footer-content {
        grid-template-columns: 1fr;
        gap: var(--spacing-lg);
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 var(--spacing-xs);
    }

    .hero {
        padding: var(--spacing-lg) 0;
    }

    .section {
        padding: var(--spacing-lg) 0;
    }

    .project-card {
        padding: var(--spacing-md);
    }

    .hero-title {
        font-size: 1.8rem;
    }
}

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

.fade-in-up {
    animation: fadeInUp 0.6s ease forwards;
}

/* Publications Section */
.publications-list {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-xl);
}

.publication-item {
    background: var(--bg-card);
    padding: var(--spacing-lg);
    border-radius: var(--radius-lg);
    border: 1px solid rgba(255, 255, 255, 0.1);
    transition: var(--transition-normal);
}

.publication-item:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
    border-color: var(--accent-primary);
}

.publication-item h3 {
    color: var(--text-primary);
    margin-bottom: var(--spacing-xs);
    font-size: 1.3rem;
}

.publication-meta {
    color: var(--accent-primary);
    font-weight: 600;
    margin-bottom: var(--spacing-sm);
    font-size: 0.9rem;
}

.publication-description {
    color: var(--text-secondary);
    margin-bottom: var(--spacing-md);
    line-height: 1.6;
}

.publication-link {
    color: var(--accent-primary);
    text-decoration: none;
    font-weight: 600;
    transition: var(--transition-fast);
}

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

.publications-footer {
    text-align: center;
}

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

.contact-info p {
    color: var(--text-secondary);
    margin-bottom: var(--spacing-xl);
    font-size: 1.1rem;
    line-height: 1.6;
}

.contact-links {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--spacing-md);
}

.contact-link {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-md);
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    border: 1px solid rgba(255, 255, 255, 0.1);
    color: var(--text-primary);
    text-decoration: none;
    transition: var(--transition-normal);
    font-weight: 500;
}

.contact-link:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
    border-color: var(--accent-primary);
    color: var(--accent-primary);
}

.contact-link span {
    font-size: 1.2rem;
}

/* Scrollbar styling */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: var(--bg-secondary);
}

::-webkit-scrollbar-thumb {
    background: var(--accent-primary);
    border-radius: var(--radius-sm);
}

::-webkit-scrollbar-thumb:hover {
    background: #0099cc;
}