/* ===================================
   CSS Variables & Design System
   =================================== */
:root {
    /* Colors */
    --primary: hsl(238, 83%, 67%);
    --primary-dark: hsl(238, 83%, 57%);
    --secondary: hsl(271, 91%, 65%);
    --accent: hsl(330, 81%, 60%);
    --success: hsl(158, 64%, 52%);
    --warning: hsl(38, 92%, 50%);
    
    /* Backgrounds */
    --bg-primary: hsl(222, 47%, 11%);
    --bg-secondary: hsl(217, 33%, 17%);
    --bg-tertiary: hsl(215, 28%, 23%);
    --bg-card: hsla(217, 33%, 17%, 0.6);
    
    /* Text */
    --text-primary: hsl(210, 40%, 98%);
    --text-secondary: hsl(214, 32%, 91%);
    --text-muted: hsl(215, 20%, 65%);
    
    /* Borders */
    --border-color: hsla(215, 28%, 35%, 0.3);
    --border-hover: hsla(238, 83%, 67%, 0.4);
    
    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 2rem;
    --spacing-lg: 4rem;
    --spacing-xl: 6rem;
    
    /* Typography */
    --font-body: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-mono: 'JetBrains Mono', 'Fira Code', 'Courier New', monospace;
    
    /* Transitions */
    --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-base: 250ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 400ms cubic-bezier(0.4, 0, 0.2, 1);
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-body);
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.7;
    overflow-x: hidden;
}

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

/* ===================================
   Hero Section
   =================================== */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
    padding: var(--spacing-lg) 0;
}

.hero-background {
    position: absolute;
    inset: 0;
    background: 
        radial-gradient(circle at 20% 30%, hsla(238, 83%, 67%, 0.15) 0%, transparent 50%),
        radial-gradient(circle at 80% 70%, hsla(271, 91%, 65%, 0.15) 0%, transparent 50%),
        radial-gradient(circle at 50% 50%, hsla(330, 81%, 60%, 0.1) 0%, transparent 70%);
    animation: float 20s ease-in-out infinite;
}

@keyframes float {
    0%, 100% { transform: translateY(0) scale(1); }
    50% { transform: translateY(-20px) scale(1.05); }
}

.hero-content {
    position: relative;
    z-index: 1;
    text-align: center;
}

.badge {
    display: inline-block;
    padding: var(--spacing-xs) var(--spacing-sm);
    background: hsla(238, 83%, 67%, 0.1);
    border: 1px solid var(--primary);
    border-radius: 50px;
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--primary);
    margin-bottom: var(--spacing-md);
    letter-spacing: 0.5px;
    text-transform: uppercase;
}

.hero-title {
    font-size: clamp(2.5rem, 8vw, 5rem);
    font-weight: 800;
    line-height: 1.1;
    margin-bottom: var(--spacing-sm);
    letter-spacing: -0.02em;
}

.gradient-text {
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 50%, var(--accent) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: clamp(1.1rem, 2vw, 1.3rem);
    color: var(--text-secondary);
    max-width: 800px;
    margin: 0 auto var(--spacing-lg);
    line-height: 1.8;
}

.hero-stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: var(--spacing-md);
    max-width: 700px;
    margin: 0 auto var(--spacing-lg);
}

.stat-card {
    background: var(--bg-card);
    backdrop-filter: blur(10px);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: var(--spacing-md);
    transition: all var(--transition-base);
}

.stat-card:hover {
    transform: translateY(-5px);
    border-color: var(--border-hover);
    box-shadow: 0 10px 40px hsla(238, 83%, 67%, 0.2);
}

.stat-value {
    font-size: 2.5rem;
    font-weight: 700;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.stat-label {
    font-size: 0.875rem;
    color: var(--text-muted);
    margin-top: var(--spacing-xs);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

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

.btn {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-xs);
    padding: 1rem 2rem;
    border-radius: 12px;
    font-weight: 600;
    font-size: 1rem;
    text-decoration: none;
    transition: all var(--transition-base);
    cursor: pointer;
    border: none;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    color: white;
    box-shadow: 0 4px 20px hsla(238, 83%, 67%, 0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 30px hsla(238, 83%, 67%, 0.5);
}

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

.btn-secondary:hover {
    border-color: var(--primary);
    background: hsla(238, 83%, 67%, 0.1);
}

.scroll-indicator {
    position: absolute;
    bottom: 2rem;
    left: 50%;
    transform: translateX(-50%);
}

.scroll-icon {
    width: 24px;
    height: 40px;
    border: 2px solid var(--text-muted);
    border-radius: 20px;
    position: relative;
}

.scroll-icon::before {
    content: '';
    position: absolute;
    top: 8px;
    left: 50%;
    transform: translateX(-50%);
    width: 4px;
    height: 8px;
    background: var(--primary);
    border-radius: 2px;
    animation: scroll 2s ease-in-out infinite;
}

@keyframes scroll {
    0%, 100% { transform: translate(-50%, 0); opacity: 1; }
    50% { transform: translate(-50%, 12px); opacity: 0.3; }
}

/* ===================================
   Sections
   =================================== */
.section {
    padding: var(--spacing-xl) 0;
    position: relative;
}

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

.section-title {
    font-size: clamp(2rem, 5vw, 3rem);
    font-weight: 700;
    text-align: center;
    margin-bottom: var(--spacing-sm);
    letter-spacing: -0.02em;
}

.section-subtitle {
    font-size: 1.2rem;
    color: var(--text-muted);
    text-align: center;
    max-width: 700px;
    margin: 0 auto var(--spacing-lg);
}

.subsection-title {
    font-size: 1.8rem;
    font-weight: 600;
    margin: var(--spacing-lg) 0 var(--spacing-md);
    text-align: center;
}

/* ===================================
   Problem & Solution Cards
   =================================== */
.two-column {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-md);
    margin-top: var(--spacing-lg);
}

.problem-card,
.solution-card {
    background: var(--bg-card);
    backdrop-filter: blur(10px);
    border: 1px solid var(--border-color);
    border-radius: 20px;
    padding: var(--spacing-lg);
    transition: all var(--transition-base);
}

.problem-card:hover,
.solution-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 20px 60px hsla(0, 0%, 0%, 0.3);
}

.problem-card {
    border-left: 4px solid var(--warning);
}

.solution-card {
    border-left: 4px solid var(--success);
}

.icon-wrapper {
    width: 60px;
    height: 60px;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2rem;
    margin-bottom: var(--spacing-md);
}

.problem-icon {
    background: hsla(38, 92%, 50%, 0.1);
}

.solution-icon {
    background: hsla(158, 64%, 52%, 0.1);
}

.problem-card h3,
.solution-card h3 {
    font-size: 1.5rem;
    margin-bottom: var(--spacing-md);
}

.problem-list,
.solution-list {
    list-style: none;
    padding: 0;
}

.problem-list li,
.solution-list li {
    padding: var(--spacing-xs) 0;
    color: var(--text-secondary);
    line-height: 1.8;
}

.problem-list li::before {
    content: '⚠ ';
    color: var(--warning);
    margin-right: var(--spacing-xs);
}

.solution-list li::before {
    content: '✓ ';
    color: var(--success);
    margin-right: var(--spacing-xs);
}

/* ===================================
   Architecture Cards
   =================================== */
.architecture-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-md);
    margin-top: var(--spacing-lg);
}

.arch-card {
    background: var(--bg-card);
    backdrop-filter: blur(10px);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: var(--spacing-md);
    transition: all var(--transition-base);
}

.arch-card:hover {
    transform: translateY(-8px);
    border-color: var(--border-hover);
    box-shadow: 0 15px 50px hsla(238, 83%, 67%, 0.2);
}

.arch-icon {
    font-size: 3rem;
    margin-bottom: var(--spacing-sm);
}

.arch-card h3 {
    font-size: 1.3rem;
    margin-bottom: var(--spacing-sm);
}

.arch-card p {
    color: var(--text-secondary);
    margin-bottom: var(--spacing-sm);
    line-height: 1.7;
}

.tech-tag {
    display: inline-block;
    padding: 0.4rem 0.8rem;
    background: hsla(238, 83%, 67%, 0.15);
    border: 1px solid var(--primary);
    border-radius: 6px;
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--primary);
    margin-top: var(--spacing-xs);
}

code {
    font-family: var(--font-mono);
    background: hsla(238, 83%, 67%, 0.1);
    padding: 0.2rem 0.5rem;
    border-radius: 4px;
    font-size: 0.9em;
    color: var(--primary);
}

/* ===================================
   Flowcharts
   =================================== */
.flowchart-container {
    margin: var(--spacing-lg) 0;
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: var(--spacing-lg);
    overflow-x: auto;
}

.mermaid {
    display: flex;
    justify-content: center;
    min-height: 300px;
}

/* ===================================
   Performance Charts
   =================================== */
.benchmark-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
    gap: var(--spacing-md);
    margin: var(--spacing-lg) 0;
}

.chart-container {
    background: var(--bg-card);
    backdrop-filter: blur(10px);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: var(--spacing-md);
}

.chart-container h3 {
    font-size: 1.2rem;
    margin-bottom: var(--spacing-md);
    text-align: center;
    color: var(--text-secondary);
}

.chart-container canvas {
    max-height: 300px;
}

.metrics-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-md);
    margin-top: var(--spacing-lg);
}

.metric-card {
    display: flex;
    gap: var(--spacing-md);
    background: var(--bg-card);
    backdrop-filter: blur(10px);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: var(--spacing-md);
    transition: all var(--transition-base);
}

.metric-card:hover {
    transform: translateY(-5px);
    border-color: var(--border-hover);
    box-shadow: 0 10px 40px hsla(238, 83%, 67%, 0.15);
}

.metric-icon {
    font-size: 2.5rem;
    flex-shrink: 0;
}

.metric-content {
    flex: 1;
}

.metric-title {
    font-size: 0.875rem;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-bottom: 0.5rem;
}

.metric-number {
    font-size: 2rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
}

.metric-number span {
    font-size: 1rem;
    color: var(--text-muted);
    font-weight: 400;
}

.metric-description {
    font-size: 0.875rem;
    color: var(--text-secondary);
    line-height: 1.5;
}

/* ===================================
   Code Showcase
   =================================== */
.tabs {
    margin-top: var(--spacing-lg);
}

.tab-buttons {
    display: flex;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-md);
    flex-wrap: wrap;
    justify-content: center;
}

.tab-button {
    padding: 0.8rem 1.5rem;
    background: transparent;
    border: 2px solid var(--border-color);
    border-radius: 12px;
    color: var(--text-muted);
    font-weight: 600;
    font-size: 0.95rem;
    cursor: pointer;
    transition: all var(--transition-base);
    font-family: var(--font-body);
}

.tab-button:hover {
    border-color: var(--primary);
    color: var(--text-primary);
}

.tab-button.active {
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    border-color: transparent;
    color: white;
}

.tab-content {
    display: none;
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    overflow: hidden;
    animation: fadeIn var(--transition-base);
}

.tab-content.active {
    display: block;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

.code-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--spacing-sm) var(--spacing-md);
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--border-color);
}

.code-file {
    font-family: var(--font-mono);
    font-size: 0.875rem;
    color: var(--text-secondary);
}

.code-lang {
    font-size: 0.75rem;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.tab-content pre {
    margin: 0;
    padding: var(--spacing-md);
    overflow-x: auto;
    font-family: var(--font-mono);
    font-size: 0.9rem;
    line-height: 1.6;
}

.tab-content code {
    background: transparent;
    color: var(--text-primary);
    padding: 0;
}

.code-benefit {
    padding: var(--spacing-md);
    background: hsla(158, 64%, 52%, 0.1);
    border-top: 1px solid var(--border-color);
    color: var(--text-secondary);
    font-size: 0.95rem;
}

.code-benefit strong {
    color: var(--success);
}

/* ===================================
   Tech Stack
   =================================== */
.tech-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: var(--spacing-md);
    margin-top: var(--spacing-lg);
}

.tech-card {
    background: var(--bg-card);
    backdrop-filter: blur(10px);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: var(--spacing-md);
}

.tech-card h4 {
    font-size: 1.2rem;
    margin-bottom: var(--spacing-md);
    color: var(--primary);
}

.tech-card ul {
    list-style: none;
    padding: 0;
}

.tech-card li {
    padding: var(--spacing-xs) 0;
    color: var(--text-secondary);
    line-height: 1.7;
}

.tech-card li::before {
    content: '▸';
    color: var(--primary);
    margin-right: var(--spacing-xs);
    font-weight: bold;
}

/* ===================================
   Roadmap
   =================================== */
.roadmap {
    max-width: 900px;
    margin: var(--spacing-lg) auto;
}

.roadmap-item {
    display: flex;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-lg);
    position: relative;
}

.roadmap-item:not(:last-child)::after {
    content: '';
    position: absolute;
    left: 30px;
    top: 60px;
    width: 2px;
    height: calc(100% + var(--spacing-md));
    background: linear-gradient(180deg, var(--primary) 0%, transparent 100%);
}

.roadmap-marker {
    flex-shrink: 0;
    width: 60px;
    height: 60px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    font-weight: 700;
    color: white;
    box-shadow: 0 4px 20px hsla(238, 83%, 67%, 0.4);
}

.roadmap-content {
    flex: 1;
    background: var(--bg-card);
    backdrop-filter: blur(10px);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: var(--spacing-md);
}

.roadmap-content h4 {
    font-size: 1.3rem;
    margin-bottom: var(--spacing-xs);
}

.roadmap-content p {
    color: var(--text-secondary);
    line-height: 1.7;
}

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

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

.footer-main h3 {
    font-size: 1.5rem;
    margin-bottom: var(--spacing-xs);
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.footer-main p {
    color: var(--text-muted);
    max-width: 400px;
}

.footer-link {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-xs);
    padding: 0.8rem 1.5rem;
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    color: var(--text-primary);
    text-decoration: none;
    font-weight: 600;
    transition: all var(--transition-base);
}

.footer-link:hover {
    border-color: var(--primary);
    transform: translateY(-2px);
    box-shadow: 0 4px 20px hsla(238, 83%, 67%, 0.2);
}

.footer-bottom {
    text-align: center;
    padding-top: var(--spacing-md);
    border-top: 1px solid var(--border-color);
    color: var(--text-muted);
    font-size: 0.875rem;
}

/* ===================================
   Responsive Design
   =================================== */
@media (max-width: 768px) {
    .hero {
        min-height: auto;
        padding: var(--spacing-lg) 0;
    }
    
    .hero-stats {
        grid-template-columns: 1fr;
    }
    
    .section {
        padding: var(--spacing-lg) 0;
    }
    
    .two-column,
    .architecture-grid,
    .benchmark-grid,
    .tech-grid {
        grid-template-columns: 1fr;
    }
    
    .footer-content {
        flex-direction: column;
    }
    
    .tab-buttons {
        flex-direction: column;
    }
    
    .tab-button {
        width: 100%;
    }
    
    .flowchart-container {
        padding: var(--spacing-sm);
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 var(--spacing-sm);
    }
    
    .hero-title {
        font-size: 2rem;
    }
    
    .section-title {
        font-size: 1.8rem;
    }
    
    .stat-value {
        font-size: 2rem;
    }
    
    .btn {
        width: 100%;
        justify-content: center;
    }
}