/* ============================================
   CSS Custom Properties
   ============================================ */
:root {
    --color-bg: #0a0e1a;
    --color-bg-alt: #111827;
    --color-text: #f3f4f6;
    --color-text-muted: #9ca3af;
    --color-primary: #6366f1;
    --color-primary-hover: #818cf8;
    --color-secondary: #8b5cf6;
    --color-accent: #06b6d4;
    --color-border: #1f2937;
    --color-code-bg: #1e293b;
    --color-card-bg: #1f2937;

    --font-heading: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    --font-mono: 'SF Mono', 'Fira Code', monospace;

    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 2rem;
    --spacing-lg: 4rem;
    --spacing-xl: 8rem;

    --radius-sm: 0.375rem;
    --radius-md: 0.75rem;
    --radius-lg: 1rem;
}

.light-theme {
    --color-bg: #ffffff;
    --color-bg-alt: #f9fafb;
    --color-text: #111827;
    --color-text-muted: #6b7280;
    --color-border: #e5e7eb;
    --color-code-bg: #f3f4f6;
    --color-card-bg: #ffffff;
}

/* ============================================
   Base Styles
   ============================================ */
*, *::before, *::after {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    margin: 0;
    font-family: var(--font-heading);
    background: var(--color-bg);
    color: var(--color-text);
    line-height: 1.6;
    transition: background 0.3s, color 0.3s;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

/* ============================================
   Navigation
   ============================================ */
.nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(10, 14, 26, 0.8);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--color-border);
}

.light-theme .nav {
    background: rgba(255, 255, 255, 0.8);
}

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

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--color-primary);
    text-decoration: none;
    background: linear-gradient(135deg, var(--color-primary), var(--color-secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.nav-links {
    display: flex;
    gap: var(--spacing-md);
    list-style: none;
    margin: 0;
    padding: 0;
}

.nav-links a {
    color: var(--color-text-muted);
    text-decoration: none;
    font-size: 0.9375rem;
    font-weight: 500;
    transition: color 0.2s;
}

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

.theme-toggle {
    background: var(--color-card-bg);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    padding: var(--spacing-xs);
    cursor: pointer;
    color: var(--color-text);
    transition: all 0.2s;
}

.theme-toggle:hover {
    background: var(--color-border);
}

/* ============================================
   Hero Section
   ============================================ */
.hero {
    min-height: 100vh;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-lg);
    align-items: center;
    padding: calc(60px + var(--spacing-lg)) var(--spacing-md) var(--spacing-lg);
    max-width: 1200px;
    margin: 0 auto;
}

.hero-content {
    animation: fadeIn 0.8s ease-out;
}

.hero-greeting {
    color: var(--color-primary);
    font-weight: 600;
    font-size: 1.125rem;
    margin: 0 0 var(--spacing-xs);
}

.hero-title {
    font-size: clamp(2.5rem, 5vw, 4rem);
    font-weight: 800;
    margin: 0 0 var(--spacing-sm);
    line-height: 1.1;
    background: linear-gradient(135deg, var(--color-text), var(--color-primary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--color-text-muted);
    margin: 0 0 var(--spacing-sm);
}

.hero-description {
    font-size: 1.125rem;
    color: var(--color-text-muted);
    max-width: 500px;
    margin: 0 0 var(--spacing-md);
}

.hero-actions {
    display: flex;
    gap: var(--spacing-sm);
    flex-wrap: wrap;
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.75rem 1.5rem;
    border-radius: var(--radius-md);
    font-weight: 600;
    text-decoration: none;
    transition: all 0.2s;
}

.btn-primary {
    background: linear-gradient(135deg, var(--color-primary), var(--color-secondary));
    color: white;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 40px -10px rgba(99, 102, 241, 0.5);
}

.btn-secondary {
    background: var(--color-card-bg);
    color: var(--color-text);
    border: 1px solid var(--color-border);
}

.btn-secondary:hover {
    background: var(--color-border);
}

.hero-social {
    display: flex;
    gap: var(--spacing-sm);
    margin-top: var(--spacing-md);
}

.hero-social a {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    border-radius: var(--radius-md);
    background: var(--color-card-bg);
    color: var(--color-text-muted);
    transition: all 0.2s;
}

.hero-social a:hover {
    background: var(--color-primary);
    color: white;
    transform: translateY(-2px);
}

/* Code Block */
.code-block {
    background: var(--color-code-bg);
    border-radius: var(--radius-lg);
    border: 1px solid var(--color-border);
    overflow: hidden;
    animation: slideIn 0.8s ease-out;
}

.code-header {
    display: flex;
    gap: 0.5rem;
    padding: var(--spacing-sm);
    border-bottom: 1px solid var(--color-border);
}

.dot {
    width: 12px;
    height: 12px;
    border-radius: 50%;
}

.dot.red { background: #ef4444; }
.dot.yellow { background: #f59e0b; }
.dot.green { background: #22c55e; }

.code-content {
    padding: var(--spacing-md);
    font-family: var(--font-mono);
    font-size: 0.875rem;
    line-height: 1.8;
    overflow-x: auto;
}

.code-content .keyword { color: #c792ea; }
.code-content .variable { color: #82aaff; }
.code-content .property { color: #ffcb6b; }
.code-content .string { color: #c3e88d; }

/* ============================================
   Sections
   ============================================ */
section {
    padding: var(--spacing-xl) var(--spacing-md);
}

.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    text-align: center;
    margin: 0 0 var(--spacing-lg);
}

/* About Section */
.about {
    background: var(--color-bg-alt);
}

.about-content {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: var(--spacing-lg);
    align-items: center;
}

.about-text p {
    font-size: 1.125rem;
    color: var(--color-text-muted);
    margin: 0 0 var(--spacing-sm);
}

.about-stats {
    display: grid;
    gap: var(--spacing-md);
}

.stat {
    text-align: center;
    padding: var(--spacing-md);
    background: var(--color-card-bg);
    border-radius: var(--radius-lg);
    border: 1px solid var(--color-border);
}

.stat-number {
    display: block;
    font-size: 2.5rem;
    font-weight: 800;
    background: linear-gradient(135deg, var(--color-primary), var(--color-secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.stat-label {
    display: block;
    font-size: 0.875rem;
    color: var(--color-text-muted);
    margin-top: var(--spacing-xs);
}

/* Work Section */
.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-md);
}

.project-card {
    background: var(--color-card-bg);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: var(--spacing-md);
    transition: all 0.3s;
}

.project-card:hover {
    border-color: var(--color-primary);
    transform: translateY(-4px);
    box-shadow: 0 20px 40px -20px rgba(99, 102, 241, 0.3);
}

.project-icon {
    font-size: 2rem;
    margin-bottom: var(--spacing-sm);
}

.project-card h3 {
    margin: 0 0 var(--spacing-xs);
    font-size: 1.25rem;
}

.project-card p {
    color: var(--color-text-muted);
    margin: 0 0 var(--spacing-sm);
}

.project-tags {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-xs);
}

.tag {
    padding: 0.25rem 0.75rem;
    background: var(--color-bg-alt);
    border-radius: 9999px;
    font-size: 0.75rem;
    color: var(--color-primary);
}

/* Skills Section */
.skills {
    background: var(--color-bg-alt);
}

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

.skill-category h3 {
    margin: 0 0 var(--spacing-sm);
    font-size: 1.25rem;
}

.skill-list {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-xs);
}

.skill {
    padding: 0.5rem 1rem;
    background: var(--color-card-bg);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    font-size: 0.875rem;
}

/* Contact Section */
.contact-intro {
    text-align: center;
    color: var(--color-text-muted);
    font-size: 1.125rem;
    margin: 0 auto var(--spacing-md);
    max-width: 600px;
}

.contact-links {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-md);
    max-width: 800px;
    margin: 0 auto;
}

.contact-link {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-md);
    background: var(--color-card-bg);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    text-decoration: none;
    transition: all 0.2s;
}

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

.contact-icon {
    font-size: 1.5rem;
}

.contact-label {
    display: block;
    font-size: 0.75rem;
    color: var(--color-text-muted);
}

.contact-value {
    font-weight: 600;
    color: var(--color-text);
}

/* Footer */
.footer {
    padding: var(--spacing-md);
    text-align: center;
    border-top: 1px solid var(--color-border);
}

.footer p {
    margin: 0 0 var(--spacing-xs);
    color: var(--color-text-muted);
}

.footer-note {
    font-size: 0.875rem;
}

/* ============================================
   Animations
   ============================================ */
@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateX(20px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

/* ============================================
   Responsive Design
   ============================================ */
@media (max-width: 768px) {
    .hero {
        grid-template-columns: 1fr;
        padding-top: calc(60px + var(--spacing-md));
    }

    .hero-visual {
        order: -1;
    }

    .about-content {
        grid-template-columns: 1fr;
    }

    .nav-links {
        gap: var(--spacing-sm);
    }

    .nav-links li:nth-child(n+3) {
        display: none;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 2rem;
    }

    .hero-actions {
        flex-direction: column;
    }

    .btn {
        width: 100%;
    }
}