/* CSS Custom Properties */
:root {
    /* Colors */
    --color-primary: #10b981;
    --color-primary-dark: #059669;
    --color-primary-light: #34d399;
    --color-bg-primary: #0f172a;
    --color-bg-secondary: #1e293b;
    --color-bg-tertiary: #334155;
    --color-text-primary: #f8fafc;
    --color-text-secondary: #cbd5e1;
    --color-text-muted: #94a3b8;
    --color-border: #475569;
    --color-accent: var(--color-primary);
    
    /* Typography */
    --font-family-primary: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
    --font-family-mono: 'SF Mono', Monaco, Inconsolata, 'Roboto Mono', Consolas, 'Courier New', monospace;
    
    --font-size-xs: 0.75rem;
    --font-size-sm: 0.875rem;
    --font-size-base: 1rem;
    --font-size-lg: 1.125rem;
    --font-size-xl: 1.25rem;
    --font-size-2xl: 1.5rem;
    --font-size-3xl: 1.875rem;
    --font-size-4xl: 2.25rem;
    --font-size-5xl: 3rem;
    
    --font-weight-normal: 400;
    --font-weight-medium: 500;
    --font-weight-semibold: 600;
    --font-weight-bold: 700;
    
    --line-height-tight: 1.25;
    --line-height-normal: 1.5;
    --line-height-relaxed: 1.75;
    
    /* Spacing */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
    --spacing-3xl: 4rem;
    --spacing-4xl: 6rem;
    
    /* Layout */
    --container-max-width: 1200px;
    --border-radius: 0.5rem;
    --border-radius-lg: 1rem;
    
    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    
    /* Transitions */
    --transition-fast: 0.15s ease-in-out;
    --transition-normal: 0.3s ease-in-out;
    --transition-slow: 0.5s ease-in-out;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-family-primary);
    font-size: var(--font-size-base);
    line-height: var(--line-height-normal);
    color: var(--color-text-primary);
    background-color: var(--color-bg-primary);
    overflow-x: hidden;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    line-height: var(--line-height-tight);
    font-weight: var(--font-weight-bold);
    margin-bottom: var(--spacing-md);
}

h1 {
    font-size: var(--font-size-5xl);
}

h2 {
    font-size: var(--font-size-4xl);
}

h3 {
    font-size: var(--font-size-2xl);
}

p {
    margin-bottom: var(--spacing-md);
    color: var(--color-text-secondary);
}

a {
    color: var(--color-primary);
    text-decoration: none;
    transition: color var(--transition-fast);
}

a:hover {
    color: var(--color-primary-light);
}

/* Layout Utilities */
.container {
    max-width: var(--container-max-width);
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
}

.text-accent {
    color: var(--color-accent);
}

/* Section Styles */
section {
    padding: var(--spacing-4xl) 0;
}

.section-header {
    text-align: center;
    margin-bottom: var(--spacing-4xl);
}

.section-title {
    font-size: var(--font-size-4xl);
    margin-bottom: var(--spacing-lg);
    color: var(--color-text-primary);
}

.section-subtitle {
    font-size: var(--font-size-xl);
    color: var(--color-text-secondary);
    max-width: 600px;
    margin: 0 auto;
}

.section-description {
    font-size: var(--font-size-lg);
    color: var(--color-text-secondary);
    margin-bottom: var(--spacing-xl);
}

/* Navigation */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background-color: rgba(15, 23, 42, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--color-border);
    z-index: 1000;
    transition: all var(--transition-normal);
}

.nav-container {
    max-width: var(--container-max-width);
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 70px;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: var(--font-size-xl);
    font-weight: var(--font-weight-bold);
    color: var(--color-text-primary);
}

.logo-icon {
    fill: var(--color-primary);
}

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

.nav-link {
    color: var(--color-text-secondary);
    font-weight: var(--font-weight-medium);
    transition: color var(--transition-fast);
    position: relative;
}

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

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

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

.nav-toggle {
    display: none;
    flex-direction: column;
    cursor: pointer;
    gap: 4px;
}

.bar {
    width: 25px;
    height: 3px;
    background-color: var(--color-text-primary);
    transition: all var(--transition-fast);
}

/* Hero Section */
.hero {
    padding: 120px 0 var(--spacing-4xl);
    background: linear-gradient(135deg, var(--color-bg-primary) 0%, var(--color-bg-secondary) 100%);
    min-height: 100vh;
    display: flex;
    align-items: center;
}

.hero-container {
    max-width: var(--container-max-width);
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-4xl);
    align-items: center;
}

.hero-title {
    font-size: var(--font-size-5xl);
    font-weight: var(--font-weight-bold);
    line-height: var(--line-height-tight);
    margin-bottom: var(--spacing-lg);
}

.hero-subtitle {
    font-size: var(--font-size-xl);
    color: var(--color-text-secondary);
    margin-bottom: var(--spacing-2xl);
    line-height: var(--line-height-relaxed);
}

.hero-buttons {
    display: flex;
    gap: var(--spacing-lg);
    flex-wrap: wrap;
}

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

.code-animation {
    background-color: var(--color-bg-secondary);
    border: 1px solid var(--color-border);
    border-radius: var(--border-radius-lg);
    padding: var(--spacing-xl);
    font-family: var(--font-family-mono);
    font-size: var(--font-size-lg);
    box-shadow: var(--shadow-xl);
    animation: float 6s ease-in-out infinite;
}

.code-line {
    margin-bottom: var(--spacing-sm);
    opacity: 0;
    animation: fadeInUp 0.8s ease-out forwards;
}

.code-line:nth-child(1) {
    animation-delay: 0.5s;
}

.code-line:nth-child(2) {
    animation-delay: 1s;
}

.code-line:nth-child(3) {
    animation-delay: 1.5s;
}

.code-keyword {
    color: #ff79c6;
}

.code-function {
    color: var(--color-primary);
}

.code-string {
    color: #f1fa8c;
}

/* Features Section */
.features {
    background-color: var(--color-bg-secondary);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-xl);
}

.feature-card {
    background-color: var(--color-bg-primary);
    border: 1px solid var(--color-border);
    border-radius: var(--border-radius-lg);
    padding: var(--spacing-2xl);
    text-align: center;
    transition: all var(--transition-normal);
    position: relative;
    overflow: hidden;
}

.feature-card:hover {
    transform: translateY(-5px);
    border-color: var(--color-primary);
    box-shadow: var(--shadow-xl);
}

.feature-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 3px;
    background: linear-gradient(90deg, transparent, var(--color-primary), transparent);
    transition: left var(--transition-slow);
}

.feature-card:hover::before {
    left: 100%;
}

.feature-icon {
    margin-bottom: var(--spacing-lg);
    fill: var(--color-primary);
}

.feature-title {
    margin-bottom: var(--spacing-md);
    color: var(--color-text-primary);
}

.feature-description {
    color: var(--color-text-secondary);
    line-height: var(--line-height-relaxed);
}

/* Learning Section */
.learning-content {
    display: block;
    text-align: center;
}

.learning-list {
    margin-bottom: var(--spacing-xl);
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.learning-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-lg);
    color: var(--color-text-secondary);
    text-align: left;
}

.learning-icon {
    fill: var(--color-primary);
    flex-shrink: 0;
}

/* Growth Section */
.growth {
    background-color: var(--color-bg-secondary);
}

.growth-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-xl);
}

.growth-card {
    background-color: var(--color-bg-primary);
    border: 1px solid var(--color-border);
    border-radius: var(--border-radius-lg);
    padding: var(--spacing-2xl);
    position: relative;
    transition: all var(--transition-normal);
}

.growth-card:hover {
    transform: translateY(-5px);
    border-color: var(--color-primary);
    box-shadow: var(--shadow-xl);
}

.growth-number {
    position: absolute;
    top: -15px;
    left: var(--spacing-xl);
    background-color: var(--color-primary);
    color: var(--color-bg-primary);
    width: 40px;
    height: 40px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: var(--font-weight-bold);
    font-size: var(--font-size-lg);
}

.growth-title {
    margin-top: var(--spacing-lg);
    margin-bottom: var(--spacing-md);
    color: var(--color-text-primary);
}

.growth-description {
    color: var(--color-text-secondary);
    line-height: var(--line-height-relaxed);
}

/* Contact Section */
.contact-content {
    display: block;
    text-align: center;
}

.contact-methods {
    margin-top: var(--spacing-xl);
    max-width: 500px;
    margin-left: auto;
    margin-right: auto;
}

.contact-method {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-lg);
    color: var(--color-text-secondary);
    transition: color var(--transition-fast);
}

.contact-method:hover {
    color: var(--color-primary);
}

.contact-icon {
    fill: var(--color-primary);
    flex-shrink: 0;
}

/* Footer */
.footer {
    background-color: var(--color-bg-secondary);
    border-top: 1px solid var(--color-border);
    padding: var(--spacing-2xl) 0 var(--spacing-lg);
}

.footer-content {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-lg);
}

.footer-logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: var(--font-size-lg);
    font-weight: var(--font-weight-bold);
    color: var(--color-text-primary);
}

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

.footer-bottom {
    text-align: center;
    padding-top: var(--spacing-lg);
    border-top: 1px solid var(--color-border);
    color: var(--color-text-muted);
    font-size: var(--font-size-sm);
}

/* Animations */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes float {
    0%, 100% {
        transform: translateY(0);
    }
    50% {
        transform: translateY(-10px);
    }
}

/* Utility Classes */
.btn-full {
    width: 100%;
}