/* ============================================
   SentiChain - Professional Design System
   ============================================ */

/* CSS Custom Properties */
:root {
    /* Colors - Restricted Palette */
    --color-bg-primary: #0a0a0b;
    --color-bg-secondary: #111113;
    --color-bg-tertiary: #18181b;
    --color-bg-elevated: #1f1f23;
    
    --color-text-primary: #fafafa;
    --color-text-secondary: #a1a1aa;
    --color-text-tertiary: #71717a;
    
    --color-accent: #10b981;
    --color-accent-dim: rgba(16, 185, 129, 0.15);
    --color-accent-hover: #059669;
    
    --color-border: #27272a;
    --color-border-hover: #3f3f46;
    
    /* Typography */
    --font-sans: 'IBM Plex Sans', -apple-system, BlinkMacSystemFont, sans-serif;
    --font-mono: 'IBM Plex Mono', 'Fira Code', monospace;
    
    /* Spacing */
    --space-xs: 0.25rem;
    --space-sm: 0.5rem;
    --space-md: 1rem;
    --space-lg: 1.5rem;
    --space-xl: 2rem;
    --space-2xl: 3rem;
    --space-3xl: 4rem;
    --space-4xl: 6rem;
    
    /* Sizing */
    --max-width: 1200px;
    --nav-height: 64px;
    
    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-base: 200ms ease;
    --transition-slow: 300ms ease;
    
    /* Border Radius */
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;
}

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

html {
    font-size: 16px;
    scroll-behavior: smooth;
    overflow-x: hidden;
}

body {
    font-family: var(--font-sans);
    background-color: var(--color-bg-primary);
    color: var(--color-text-primary);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    overflow-x: hidden;
    width: 100%;
}

a {
    color: inherit;
    text-decoration: none;
}

img {
    max-width: 100%;
    height: auto;
}

/* ============================================
   Navigation
   ============================================ */
.nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: var(--nav-height);
    background: rgba(10, 10, 11, 0.8);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--color-border);
    z-index: 1000;
}

.nav-container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--space-xl);
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
}

.logo-text {
    font-family: var(--font-mono);
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--color-text-primary);
    letter-spacing: -0.02em;
}

.nav-links {
    display: flex;
    align-items: center;
    gap: var(--space-lg);
}

.nav-link {
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--color-text-secondary);
    transition: color var(--transition-fast);
    padding: var(--space-sm) 0;
}

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

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

.nav-mobile-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: var(--space-md);
    z-index: 1001;
    -webkit-tap-highlight-color: transparent;
}

.nav-mobile-toggle span {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--color-text-primary);
    transition: var(--transition-fast);
}

.nav-mobile-toggle.active span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
}

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

.nav-mobile-toggle.active span:nth-child(3) {
    transform: rotate(-45deg) translate(5px, -5px);
}

/* ============================================
   Buttons
   ============================================ */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: var(--space-sm) var(--space-lg);
    font-family: var(--font-sans);
    font-size: 0.9rem;
    font-weight: 500;
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
    cursor: pointer;
    border: none;
}

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

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

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

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

/* ============================================
   Hero Section
   ============================================ */
.hero {
    min-height: 100vh;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-4xl);
    align-items: center;
    max-width: var(--max-width);
    margin: 0 auto;
    padding: calc(var(--nav-height) + var(--space-4xl)) var(--space-xl) var(--space-4xl);
}

.hero-badge {
    display: inline-block;
    font-family: var(--font-mono);
    font-size: 0.75rem;
    font-weight: 500;
    color: var(--color-accent);
    background: var(--color-accent-dim);
    padding: var(--space-xs) var(--space-md);
    border-radius: var(--radius-sm);
    margin-bottom: var(--space-lg);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.hero-title {
    font-size: clamp(2.5rem, 5vw, 4rem);
    font-weight: 700;
    line-height: 1.1;
    letter-spacing: -0.03em;
    margin-bottom: var(--space-lg);
}

.hero-subtitle {
    font-size: 1.125rem;
    color: var(--color-text-secondary);
    line-height: 1.7;
    margin-bottom: var(--space-xl);
    max-width: 540px;
}

.hero-actions {
    display: flex;
    gap: var(--space-md);
}

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

/* Merkle Tree SVG Visualization */
.merkle-tree-svg {
    width: 100%;
    max-width: 420px;
}

.merkle-tree-svg svg {
    width: 100%;
    height: auto;
}

.merkle-tree-svg .block-border {
    fill: none;
    stroke: var(--color-text-secondary);
    stroke-width: 2;
}

.merkle-tree-svg .block-label {
    fill: var(--color-text-tertiary);
    font-family: var(--font-sans);
    font-size: 13px;
    font-weight: 500;
    text-anchor: end;
}

.merkle-tree-svg .arrow-line {
    stroke: var(--color-text-tertiary);
    stroke-width: 1.5;
    fill: none;
}

.merkle-tree-svg .arrow-head {
    fill: var(--color-text-tertiary);
}

.merkle-tree-svg .label-consensus {
    fill: var(--color-accent);
    font-family: var(--font-sans);
    font-size: 14px;
    font-weight: 600;
    text-anchor: middle;
}

.merkle-tree-svg .label-hash {
    fill: var(--color-text-secondary);
    font-family: var(--font-mono);
    font-size: 12px;
    font-weight: 500;
    text-anchor: middle;
}

.merkle-tree-svg .label-emb {
    fill: var(--color-text-secondary);
    font-family: var(--font-mono);
    font-size: 11px;
    text-anchor: middle;
}

.merkle-tree-svg .label-post {
    fill: var(--color-text-tertiary);
    font-family: var(--font-sans);
    font-size: 12px;
    font-style: italic;
    text-anchor: middle;
}

/* ============================================
   Stats Section
   ============================================ */
.stats {
    background: var(--color-bg-secondary);
    border-top: 1px solid var(--color-border);
    border-bottom: 1px solid var(--color-border);
    padding: var(--space-xl) 0;
}

.stats-container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--space-xl);
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--space-xl);
}

.stat-card {
    text-align: center;
    padding: var(--space-md);
}

.stat-value {
    font-family: var(--font-mono);
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--color-text-primary);
    margin-bottom: var(--space-xs);
}

.stat-label {
    font-size: 0.75rem;
    color: var(--color-text-tertiary);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

/* ============================================
   Features Section
   ============================================ */
.features {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: var(--space-4xl) var(--space-xl);
}

.section-header {
    text-align: center;
    margin-bottom: var(--space-3xl);
}

.section-title {
    font-size: 2rem;
    font-weight: 700;
    letter-spacing: -0.02em;
    margin-bottom: var(--space-md);
}

.section-subtitle {
    font-size: 1.125rem;
    color: var(--color-text-secondary);
    max-width: 600px;
    margin: 0 auto;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-xl);
}

.feature-card {
    background: var(--color-bg-secondary);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: var(--space-xl);
    transition: all var(--transition-base);
}

.feature-card:hover {
    border-color: var(--color-border-hover);
    transform: translateY(-2px);
}

.feature-icon {
    width: 48px;
    height: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--color-accent-dim);
    border-radius: var(--radius-md);
    margin-bottom: var(--space-lg);
}

.feature-icon svg {
    width: 24px;
    height: 24px;
    color: var(--color-accent);
}

.feature-title {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: var(--space-md);
}

.feature-description {
    font-size: 0.95rem;
    color: var(--color-text-secondary);
    line-height: 1.7;
    margin-bottom: var(--space-lg);
}

.feature-link {
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--color-accent);
    display: inline-flex;
    align-items: center;
    gap: var(--space-xs);
}

.feature-link:hover {
    text-decoration: underline;
}

/* ============================================
   CTA Section
   ============================================ */
.cta {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: var(--space-4xl) var(--space-xl);
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-4xl);
    align-items: center;
}

.cta-title {
    font-size: 2rem;
    font-weight: 700;
    letter-spacing: -0.02em;
    margin-bottom: var(--space-lg);
}

.cta-description {
    font-size: 1.125rem;
    color: var(--color-text-secondary);
    line-height: 1.7;
    margin-bottom: var(--space-xl);
}

.cta-actions {
    display: flex;
    gap: var(--space-md);
}

.cta-code {
    background: var(--color-bg-secondary);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    overflow: hidden;
}

.code-header {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    padding: var(--space-md) var(--space-lg);
    background: var(--color-bg-tertiary);
    border-bottom: 1px solid var(--color-border);
}

.code-dot {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: var(--color-border-hover);
}

.code-dot:nth-child(1) { background: #ef4444; }
.code-dot:nth-child(2) { background: #f59e0b; }
.code-dot:nth-child(3) { background: #22c55e; }

.code-title {
    margin-left: var(--space-md);
    font-family: var(--font-mono);
    font-size: 0.8rem;
    color: var(--color-text-tertiary);
}

.code-content {
    padding: var(--space-lg);
    font-family: var(--font-mono);
    font-size: 0.85rem;
    line-height: 1.8;
    overflow-x: auto;
}

.code-content code {
    color: var(--color-text-secondary);
}

.code-keyword { color: #c084fc; }
.code-string { color: #4ade80; }
.code-comment { color: var(--color-text-tertiary); }
.code-builtin { color: #60a5fa; }

/* ============================================
   Ecosystem Section
   ============================================ */
.ecosystem {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: var(--space-4xl) var(--space-xl);
}

.ecosystem-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--space-lg);
}

.ecosystem-card {
    background: var(--color-bg-secondary);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: var(--space-xl);
    transition: all var(--transition-base);
}

.ecosystem-card:hover {
    border-color: var(--color-accent);
    transform: translateY(-2px);
}

.ecosystem-title {
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: var(--space-sm);
}

.ecosystem-description {
    font-size: 0.875rem;
    color: var(--color-text-tertiary);
}

/* ============================================
   Footer
   ============================================ */
.footer {
    background: var(--color-bg-secondary);
    border-top: 1px solid var(--color-border);
    padding: var(--space-4xl) 0 var(--space-xl);
}

.footer-container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--space-xl);
    display: grid;
    grid-template-columns: 1fr 2fr;
    gap: var(--space-4xl);
}

.footer-logo {
    font-family: var(--font-mono);
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: var(--space-sm);
}

.footer-tagline {
    font-size: 0.875rem;
    color: var(--color-text-tertiary);
}

.footer-links {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--space-xl);
}

.footer-column {
    display: flex;
    flex-direction: column;
    gap: var(--space-sm);
}

.footer-heading {
    font-size: 0.8rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--color-text-tertiary);
    margin-bottom: var(--space-sm);
}

.footer-column a {
    font-size: 0.9rem;
    color: var(--color-text-secondary);
    transition: color var(--transition-fast);
}

.footer-column a:hover {
    color: var(--color-text-primary);
}

.footer-bottom {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: var(--space-xl) var(--space-xl) 0;
    border-top: 1px solid var(--color-border);
    margin-top: var(--space-3xl);
}

.footer-bottom p {
    font-size: 0.8rem;
    color: var(--color-text-tertiary);
}

/* ============================================
   Legal Pages
   ============================================ */
.legal-page {
    max-width: 800px;
    margin: 0 auto;
    padding: var(--space-3xl) var(--space-xl);
}

.legal-page h1 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: var(--space-md);
}

.legal-page .updated {
    font-size: 0.9rem;
    color: var(--color-text-tertiary);
    margin-bottom: var(--space-3xl);
}

.legal-page h2 {
    font-size: 1.25rem;
    font-weight: 600;
    margin: var(--space-2xl) 0 var(--space-md);
    color: var(--color-text-primary);
}

.legal-page p {
    color: var(--color-text-secondary);
    line-height: 1.8;
    margin-bottom: var(--space-md);
}

.legal-page ul {
    color: var(--color-text-secondary);
    padding-left: var(--space-xl);
    margin-bottom: var(--space-lg);
}

.legal-page li {
    margin-bottom: var(--space-sm);
    line-height: 1.7;
}

.legal-page a {
    color: var(--color-accent);
}

.legal-page a:hover {
    text-decoration: underline;
}

/* ============================================
   Page Layouts
   ============================================ */
.page {
    min-height: 100vh;
    padding-top: var(--nav-height);
    overflow-x: hidden;
    max-width: 100vw;
}

.page-header {
    background: var(--color-bg-secondary);
    border-bottom: 1px solid var(--color-border);
    padding: var(--space-2xl) 0;
    width: 100%;
    box-sizing: border-box;
}

.page-header-content {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--space-xl);
    box-sizing: border-box;
}

.page-title {
    font-size: 2.5rem;
    font-weight: 700;
    letter-spacing: -0.02em;
    margin-bottom: var(--space-md);
}

.page-subtitle {
    font-size: 1.125rem;
    color: var(--color-text-secondary);
    max-width: 700px;
}

.page-content {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: var(--space-3xl) var(--space-xl);
    box-sizing: border-box;
}

/* ============================================
   Content Styles
   ============================================ */
.content h2 {
    font-size: 1.75rem;
    font-weight: 600;
    margin: var(--space-3xl) 0 var(--space-lg);
    padding-top: var(--space-lg);
    border-top: 1px solid var(--color-border);
}

.content h2:first-child {
    margin-top: 0;
    padding-top: 0;
    border-top: none;
}

.content h3 {
    font-size: 1.25rem;
    font-weight: 600;
    margin: var(--space-xl) 0 var(--space-md);
}

.content p {
    color: var(--color-text-secondary);
    margin-bottom: var(--space-lg);
    line-height: 1.8;
}

.content ul, .content ol {
    color: var(--color-text-secondary);
    margin-bottom: var(--space-lg);
    padding-left: var(--space-xl);
}

.content li {
    margin-bottom: var(--space-sm);
    line-height: 1.7;
}

.content code {
    font-family: var(--font-mono);
    font-size: 0.9em;
    background: var(--color-bg-tertiary);
    padding: 2px 6px;
    border-radius: var(--radius-sm);
    color: var(--color-accent);
}

.content pre {
    background: var(--color-bg-secondary);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    padding: var(--space-lg);
    overflow-x: auto;
    margin-bottom: var(--space-lg);
}

.content pre code {
    background: none;
    padding: 0;
    color: var(--color-text-secondary);
}

/* ============================================
   Forms
   ============================================ */
.form-group {
    margin-bottom: var(--space-lg);
}

.form-label {
    display: block;
    font-size: 0.875rem;
    font-weight: 500;
    margin-bottom: var(--space-sm);
    color: var(--color-text-secondary);
}

.form-input,
.form-select {
    width: 100%;
    padding: var(--space-md);
    background: var(--color-bg-tertiary);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    color: var(--color-text-primary);
    font-family: var(--font-sans);
    font-size: 0.95rem;
    transition: all var(--transition-fast);
}

.form-input:focus,
.form-select:focus {
    outline: none;
    border-color: var(--color-accent);
    box-shadow: 0 0 0 3px var(--color-accent-dim);
}

.form-input::placeholder {
    color: var(--color-text-tertiary);
}

.form-row {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--space-lg);
}

/* ============================================
   Cards
   ============================================ */
.card {
    background: var(--color-bg-secondary);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: var(--space-xl);
}

.card-header {
    margin-bottom: var(--space-lg);
    padding-bottom: var(--space-lg);
    border-bottom: 1px solid var(--color-border);
}

.card-title {
    font-size: 1.25rem;
    font-weight: 600;
}

/* ============================================
   Tables
   ============================================ */
.table-container {
    overflow-x: auto;
    margin-bottom: var(--space-xl);
}

table {
    width: 100%;
    border-collapse: collapse;
}

th, td {
    padding: var(--space-md);
    text-align: left;
    border-bottom: 1px solid var(--color-border);
}

th {
    font-size: 0.8rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--color-text-tertiary);
    background: var(--color-bg-tertiary);
}

td {
    font-size: 0.9rem;
    color: var(--color-text-secondary);
}

tr:hover td {
    background: var(--color-bg-tertiary);
}

.table-mono {
    font-family: var(--font-mono);
    font-size: 0.85rem;
}

/* ============================================
   Utilities
   ============================================ */
.text-mono {
    font-family: var(--font-mono);
}

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

.text-muted {
    color: var(--color-text-tertiary);
}

.truncate {
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.clickable {
    cursor: pointer;
    transition: color var(--transition-fast);
}

.clickable:hover {
    color: var(--color-accent);
}

.visually-hidden {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

/* ============================================
   Responsive Design
   ============================================ */
@media (max-width: 1024px) {
    .hero {
        grid-template-columns: 1fr;
        text-align: center;
        gap: var(--space-3xl);
    }
    
    .hero-subtitle {
        margin-left: auto;
        margin-right: auto;
    }
    
    .hero-actions {
        justify-content: center;
    }
    
    /* Chart appears AFTER the buttons on mobile/tablet */
    .hero-visual {
        order: 1;
    }
    
    .hero-content {
        order: 0;
    }
    
    .network-diagram {
        width: 300px;
        height: 250px;
    }
    
    .features-grid {
        grid-template-columns: 1fr;
    }
    
    .cta {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .cta-actions {
        justify-content: center;
    }
    
    .ecosystem-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .footer-container {
        grid-template-columns: 1fr;
        gap: var(--space-2xl);
    }
}

@media (max-width: 768px) {
    :root {
        --space-xl: 1.5rem;
        --space-2xl: 2rem;
        --space-3xl: 3rem;
        --space-4xl: 4rem;
    }
    
    .nav-links {
        display: none;
        position: fixed;
        top: var(--nav-height);
        left: 0;
        right: 0;
        background: var(--color-bg-primary);
        flex-direction: column;
        padding: var(--space-lg);
        border-bottom: 1px solid var(--color-border);
        z-index: 9999;
        box-shadow: 0 4px 20px rgba(0, 0, 0, 0.5);
    }
    
    .nav-links.active {
        display: flex;
    }
    
    .nav-link {
        padding: var(--space-md) var(--space-sm);
        border-bottom: 1px solid var(--color-border);
        font-size: 1rem;
        width: 100%;
        display: block;
        -webkit-tap-highlight-color: transparent;
    }
    
    .nav-link:last-child {
        border-bottom: none;
    }
    
    .nav-mobile-toggle {
        display: flex;
        position: relative;
        z-index: 10000;
    }
    
    .nav {
        z-index: 9998;
    }
    
    .stats-container {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .ecosystem-grid {
        grid-template-columns: 1fr;
    }
    
    .footer-links {
        grid-template-columns: 1fr;
    }
    
    .hero-actions {
        flex-direction: column;
    }
    
    .cta-actions {
        flex-direction: column;
    }
    
    /* Page content should be below mobile nav */
    .page {
        position: relative;
        z-index: 1;
    }
    
    .page-header {
        padding: var(--space-xl) 0;
    }
    
    .page-title {
        font-size: 1.75rem;
    }
    
    .page-subtitle {
        font-size: 1rem;
    }
}

@media (max-width: 480px) {
    .stats-container {
        grid-template-columns: 1fr;
    }
    
    .merkle-tree-svg {
        max-width: 280px;
    }
    
    .hero-title {
        font-size: 2rem;
    }
    
    .section-title {
        font-size: 1.5rem;
    }
    
    .feature-card {
        padding: var(--space-lg);
    }
    
    .cta-code {
        display: none;
    }
    
    pre {
        font-size: 0.75rem;
        padding: var(--space-md);
    }
    
    code {
        font-size: 0.75rem;
    }
    
    table {
        font-size: 0.8rem;
    }
    
    .table-mono {
        font-size: 0.7rem;
    }
}