/* ==========================================================================
   ANTcell Website Styles
   A professional, minimal, content-first design
   ========================================================================== */

/* --------------------------------------------------------------------------
   CSS Custom Properties
   -------------------------------------------------------------------------- */
:root {
    /* Colors - Dark neutral palette */
    --color-bg-primary: #0a0a0b;
    --color-bg-secondary: #111113;
    --color-bg-tertiary: #1a1a1d;
    --color-bg-card: #16161a;
    --color-bg-card-hover: #1e1e23;
    
    --color-text-primary: #fafafa;
    --color-text-secondary: #a1a1aa;
    --color-text-tertiary: #71717a;
    
    --color-border: #27272a;
    --color-border-light: #3f3f46;
    
    --color-accent: #3b82f6;
    --color-accent-hover: #60a5fa;
    --color-accent-muted: #1e3a5f;
    
    --color-engineer: #10b981;
    --color-supervisor: #8b5cf6;
    --color-supporter: #f59e0b;
    --color-helper: #06b6d4;
    
    /* Typography */
    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --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: 2rem;
    --font-size-4xl: 2.5rem;
    --font-size-5xl: 3.5rem;
    
    --font-weight-normal: 400;
    --font-weight-medium: 500;
    --font-weight-semibold: 600;
    --font-weight-bold: 700;
    
    --line-height-tight: 1.2;
    --line-height-normal: 1.5;
    --line-height-relaxed: 1.75;
    
    /* Spacing */
    --space-1: 0.25rem;
    --space-2: 0.5rem;
    --space-3: 0.75rem;
    --space-4: 1rem;
    --space-5: 1.25rem;
    --space-6: 1.5rem;
    --space-8: 2rem;
    --space-10: 2.5rem;
    --space-12: 3rem;
    --space-16: 4rem;
    --space-20: 5rem;
    --space-24: 6rem;
    
    /* Layout */
    --container-max: 1200px;
    --container-narrow: 800px;
    
    /* Borders */
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;
    --radius-xl: 16px;
    
    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-base: 250ms ease;
}

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

html {
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

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

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

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

a:hover {
    color: var(--color-accent-hover);
}

ul {
    list-style: none;
}

/* --------------------------------------------------------------------------
   Typography
   -------------------------------------------------------------------------- */
h1, h2, h3, h4, h5, h6 {
    font-weight: var(--font-weight-semibold);
    line-height: var(--line-height-tight);
    color: var(--color-text-primary);
}

h1 {
    font-size: var(--font-size-5xl);
    font-weight: var(--font-weight-bold);
    letter-spacing: -0.02em;
}

h2 {
    font-size: var(--font-size-3xl);
    letter-spacing: -0.01em;
}

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

p {
    color: var(--color-text-secondary);
}

blockquote {
    font-size: var(--font-size-lg);
    font-style: italic;
    color: var(--color-text-secondary);
    border-left: 3px solid var(--color-accent);
    padding-left: var(--space-6);
    margin: var(--space-8) 0;
}

/* --------------------------------------------------------------------------
   Layout
   -------------------------------------------------------------------------- */
.container {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 var(--space-6);
}

.section {
    padding: var(--space-24) 0;
}

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

.section-title {
    text-align: center;
    margin-bottom: var(--space-4);
}

.section-intro {
    text-align: center;
    max-width: var(--container-narrow);
    margin: 0 auto var(--space-16);
    font-size: var(--font-size-lg);
    line-height: var(--line-height-relaxed);
}

/* --------------------------------------------------------------------------
   Header & Navigation
   -------------------------------------------------------------------------- */
.site-header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 100;
    background-color: rgba(10, 10, 11, 0.9);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--color-border);
}

.nav-container {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: var(--space-4) var(--space-6);
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    color: var(--color-text-primary);
}

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

.logo-img {
    width: 40px;
    height: 40px;
    border-radius: var(--radius-sm);
}

.logo-text {
    font-size: var(--font-size-xl);
    font-weight: var(--font-weight-semibold);
}

.nav-links {
    display: flex;
    gap: var(--space-6);
    align-items: center;
}

.nav-links a {
    color: var(--color-text-secondary);
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-medium);
    transition: color var(--transition-fast);
}

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

.language-selector {
    display: flex;
    gap: var(--space-2);
    margin-left: var(--space-4);
    padding-left: var(--space-4);
    border-left: 1px solid var(--color-border);
}

.lang-btn {
    background: transparent;
    border: 1px solid var(--color-border);
    color: var(--color-text-tertiary);
    padding: var(--space-1) var(--space-3);
    font-size: var(--font-size-xs);
    font-weight: var(--font-weight-medium);
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: all var(--transition-fast);
}

.lang-btn:hover {
    border-color: var(--color-accent);
    color: var(--color-text-primary);
}

.lang-btn.active {
    background: var(--color-accent);
    border-color: var(--color-accent);
    color: white;
}

.nav-links a {
    color: var(--color-text-secondary);
    font-size: var(--font-size-sm);
    font-weight: var(--weight-medium);
    transition: color var(--transition-fast);
}

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

.language-selector {
    display: flex;
    gap: var(--space-2);
    margin-left: var(--space-4);
    padding-left: var(--space-4);
    border-left: 1px solid var(--color-border);
}

.lang-btn {
    background: transparent;
    border: 1px solid var(--color-border);
    color: var(--color-text-tertiary);
    padding: var(--space-1) var(--space-3);
    font-size: var(--font-size-xs);
    font-weight: var(--weight-medium);
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: all var(--transition-fast);
}

.lang-btn:hover {
    border-color: var(--color-accent);
    color: var(--color-text-primary);
}

.lang-btn.active {
    background: var(--color-accent);
    border-color: var(--color-accent);
    color: white;
}

/* --------------------------------------------------------------------------
   Hero Section
   -------------------------------------------------------------------------- */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    padding-top: 80px;
    background: 
        radial-gradient(ellipse at 20% 50%, rgba(59, 130, 246, 0.08) 0%, transparent 50%),
        radial-gradient(ellipse at 80% 50%, rgba(139, 92, 246, 0.06) 0%, transparent 50%),
        var(--color-bg-primary);
}

.hero-container {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 var(--space-6);
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-16);
    align-items: center;
}

.hero-content {
    max-width: 600px;
}

.hero-title {
    font-size: clamp(3rem, 8vw, 5rem);
    margin-bottom: var(--space-4);
    background: linear-gradient(135deg, var(--color-text-primary) 0%, var(--color-text-secondary) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: var(--font-size-2xl);
    color: var(--color-text-secondary);
    margin-bottom: var(--space-8);
    font-weight: var(--font-weight-medium);
}

.hero-definition {
    font-size: var(--font-size-lg);
    line-height: var(--line-height-relaxed);
    color: var(--color-text-tertiary);
}

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

.hero-image img {
    max-width: 450px;
    width: 100%;
    border-radius: var(--radius-lg);
    box-shadow: 
        0 25px 50px -12px rgba(0, 0, 0, 0.5),
        0 0 0 1px var(--color-border);
}

/* --------------------------------------------------------------------------
   Problem Section
   -------------------------------------------------------------------------- */
.problem-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-8);
}

.problem-card {
    background-color: var(--color-bg-card);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: var(--space-8);
}

.problem-card h3 {
    margin-bottom: var(--space-4);
}

.problem-card p {
    margin-bottom: var(--space-6);
    line-height: var(--line-height-relaxed);
}

.problem-list {
    display: flex;
    flex-direction: column;
    gap: var(--space-3);
}

.problem-list li {
    position: relative;
    padding-left: var(--space-6);
    color: var(--color-text-tertiary);
    font-size: var(--font-size-sm);
}

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

/* --------------------------------------------------------------------------
   Framework Section - Triangle Diagram
   -------------------------------------------------------------------------- */
.diagram-placeholder {
    margin: var(--space-12) auto;
    max-width: 700px;
}

.diagram-wrapper {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--space-4);
}

.diagram-supervisor {
    background: linear-gradient(135deg, var(--color-supervisor), #6d28d9);
    padding: var(--space-6) var(--space-10);
    border-radius: var(--radius-lg);
    text-align: center;
}

.diagram-connector {
    width: 2px;
    height: 40px;
    background: linear-gradient(to bottom, var(--color-supervisor), var(--color-border));
}

.diagram-bottom {
    display: grid;
    grid-template-columns: 1fr 1.2fr 1fr;
    gap: var(--space-4);
    width: 100%;
}

.diagram-supporter {
    background: linear-gradient(135deg, var(--color-supporter), #d97706);
    padding: var(--space-6);
    border-radius: var(--radius-lg);
    text-align: center;
}

.diagram-engineer {
    background: linear-gradient(135deg, var(--color-engineer), #059669);
    padding: var(--space-6);
    border-radius: var(--radius-lg);
    text-align: center;
    transform: scale(1.05);
    box-shadow: 0 8px 32px rgba(16, 185, 129, 0.3);
}

.diagram-helper {
    background: linear-gradient(135deg, var(--color-helper), #0891b2);
    padding: var(--space-6);
    border-radius: var(--radius-lg);
    text-align: center;
}

.role-label {
    display: block;
    font-weight: var(--font-weight-semibold);
    font-size: var(--font-size-lg);
    color: var(--color-text-primary);
    margin-bottom: var(--space-2);
}

.role-detail {
    display: block;
    font-size: var(--font-size-xs);
    color: rgba(255, 255, 255, 0.8);
}

/* Role Cards */
.roles-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--space-6);
    margin-top: var(--space-12);
}

.role-card {
    background-color: var(--color-bg-card);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: var(--space-6);
    transition: transform var(--transition-base), box-shadow var(--transition-base);
}

.role-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.3);
}

.role-card.role-engineer {
    border-color: var(--color-engineer);
    background: linear-gradient(180deg, rgba(16, 185, 129, 0.1) 0%, var(--color-bg-card) 100%);
}

.role-icon {
    font-size: var(--font-size-2xl);
    margin-bottom: var(--space-4);
    opacity: 0.6;
}

.role-card h3 {
    margin-bottom: var(--space-2);
}

.role-subtitle {
    font-size: var(--font-size-sm);
    color: var(--color-text-tertiary);
    margin-bottom: var(--space-4);
}

.role-card > p:last-child {
    font-size: var(--font-size-sm);
    line-height: var(--line-height-relaxed);
}

.framework-note {
    margin-top: var(--space-12);
    padding: var(--space-6);
    background-color: var(--color-bg-tertiary);
    border-radius: var(--radius-lg);
    border-left: 3px solid var(--color-accent);
}

.framework-note p {
    font-size: var(--font-size-sm);
    line-height: var(--line-height-relaxed);
}

.framework-note strong {
    color: var(--color-text-primary);
}

/* --------------------------------------------------------------------------
   Platform Section
   -------------------------------------------------------------------------- */
.platform-diagram {
    margin: var(--space-12) auto;
    max-width: 700px;
}

.platform-outer {
    background-color: var(--color-bg-tertiary);
    border: 2px solid var(--color-border);
    border-radius: var(--radius-xl);
    padding: var(--space-8);
    text-align: center;
}

.platform-label {
    font-size: var(--font-size-xl);
    font-weight: var(--font-weight-semibold);
    color: var(--color-text-primary);
    margin-bottom: var(--space-2);
}

.platform-tools {
    font-size: var(--font-size-sm);
    color: var(--color-text-tertiary);
    margin-bottom: var(--space-6);
}

.platform-inner {
    background-color: var(--color-bg-card);
    border: 2px solid var(--color-accent);
    border-radius: var(--radius-lg);
    padding: var(--space-6);
}

.cell-label {
    font-size: var(--font-size-lg);
    font-weight: var(--font-weight-semibold);
    color: var(--color-accent);
    margin-bottom: var(--space-2);
}

.cell-content {
    font-size: var(--font-size-sm);
    color: var(--color-text-secondary);
}

.platform-comparison {
    display: grid;
    grid-template-columns: 1fr auto 1fr;
    gap: var(--space-8);
    align-items: start;
    margin-top: var(--space-12);
}

.comparison-card {
    background-color: var(--color-bg-card);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: var(--space-6);
}

.comparison-card h3 {
    margin-bottom: var(--space-4);
    font-size: var(--font-size-lg);
}

.comparison-card ul {
    display: flex;
    flex-direction: column;
    gap: var(--space-2);
    margin-bottom: var(--space-6);
}

.comparison-card li {
    font-size: var(--font-size-sm);
    color: var(--color-text-secondary);
    padding-left: var(--space-5);
    position: relative;
}

.comparison-card li::before {
    content: '•';
    position: absolute;
    left: 0;
    color: var(--color-accent);
}

.comparison-summary {
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-medium);
    color: var(--color-accent);
    text-align: center;
    padding-top: var(--space-4);
    border-top: 1px solid var(--color-border);
}

.comparison-divider {
    display: flex;
    align-items: center;
    padding-top: var(--space-16);
}

.comparison-divider span {
    color: var(--color-text-tertiary);
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-medium);
}

.platform-principle {
    margin-top: var(--space-12);
    text-align: center;
}

.platform-principle blockquote {
    border-left: none;
    padding-left: 0;
    max-width: var(--container-narrow);
    margin: 0 auto;
}

/* --------------------------------------------------------------------------
   Research Section
   -------------------------------------------------------------------------- */
.research-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--space-6);
}

.research-card {
    background-color: var(--color-bg-card);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: var(--space-6);
    transition: border-color var(--transition-base);
}

.research-card:hover {
    border-color: var(--color-border-light);
}

.research-card h3 {
    margin-bottom: var(--space-4);
    font-size: var(--font-size-lg);
}

.research-card p {
    font-size: var(--font-size-sm);
    line-height: var(--line-height-relaxed);
}

/* --------------------------------------------------------------------------
   Maturity Section
   -------------------------------------------------------------------------- */
.maturity-timeline {
    display: flex;
    flex-direction: column;
    gap: var(--space-6);
    max-width: var(--container-narrow);
    margin: 0 auto;
}

.maturity-level {
    display: flex;
    gap: var(--space-6);
    align-items: flex-start;
}

.level-marker {
    flex-shrink: 0;
    width: 48px;
    height: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: var(--color-bg-card);
    border: 2px solid var(--color-accent);
    border-radius: 50%;
    font-size: var(--font-size-xl);
    font-weight: var(--font-weight-bold);
    color: var(--color-accent);
}

.level-content {
    flex: 1;
    background-color: var(--color-bg-card);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: var(--space-6);
}

.level-content h3 {
    margin-bottom: var(--space-2);
}

.level-content p {
    font-size: var(--font-size-sm);
    line-height: var(--line-height-relaxed);
}

/* --------------------------------------------------------------------------
   Adoption Section
   -------------------------------------------------------------------------- */
.principles-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--space-8);
}

.principle-card {
    background-color: var(--color-bg-card);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: var(--space-8);
}

.principle-number {
    font-size: var(--font-size-3xl);
    font-weight: var(--font-weight-bold);
    color: var(--color-accent);
    opacity: 0.5;
    margin-bottom: var(--space-4);
}

.principle-card h3 {
    margin-bottom: var(--space-4);
}

.principle-card p {
    font-size: var(--font-size-sm);
    line-height: var(--line-height-relaxed);
}

.adoption-note {
    margin-top: var(--space-12);
    padding: var(--space-8);
    background-color: var(--color-bg-tertiary);
    border-radius: var(--radius-lg);
    text-align: center;
    max-width: var(--container-narrow);
    margin-left: auto;
    margin-right: auto;
}

.adoption-note h3 {
    margin-bottom: var(--space-4);
}

.adoption-note p {
    font-size: var(--font-size-sm);
    line-height: var(--line-height-relaxed);
}

/* --------------------------------------------------------------------------
   Footer
   -------------------------------------------------------------------------- */
.site-footer {
    background-color: var(--color-bg-secondary);
    border-top: 1px solid var(--color-border);
    padding: var(--space-16) 0 var(--space-8);
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: var(--space-12);
}

.footer-brand {
    display: flex;
    flex-direction: column;
    gap: var(--space-4);
}

.footer-logo {
    width: 60px;
    height: 60px;
    border-radius: var(--radius-md);
}

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

.footer-contact p {
    font-size: var(--font-size-sm);
    color: var(--color-text-tertiary);
    margin-bottom: var(--space-2);
}

.footer-contact a {
    font-size: var(--font-size-base);
}

.footer-bottom {
    padding-top: var(--space-8);
    border-top: 1px solid var(--color-border);
    text-align: center;
}

.footer-bottom p {
    font-size: var(--font-size-sm);
    color: var(--color-text-tertiary);
    font-style: italic;
    max-width: var(--container-narrow);
    margin: 0 auto;
}

/* --------------------------------------------------------------------------
   Responsive Design
   -------------------------------------------------------------------------- */
@media (max-width: 1024px) {
    .hero-container {
        grid-template-columns: 1fr;
        gap: var(--space-12);
        text-align: center;
    }
    
    .hero-content {
        max-width: none;
    }
    
    .hero-image img {
        max-width: 350px;
        margin: 0 auto;
    }
    
    .roles-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .research-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .platform-comparison {
        grid-template-columns: 1fr;
        gap: var(--space-4);
    }
    
    .comparison-divider {
        justify-content: center;
        padding: var(--space-2) 0;
    }
}

@media (max-width: 768px) {
    :root {
        --font-size-5xl: 2.5rem;
        --font-size-3xl: 1.75rem;
        --font-size-2xl: 1.25rem;
    }
    
    .nav-links {
        display: flex;
        flex-wrap: wrap;
        justify-content: center;
        gap: var(--space-3);
        padding: var(--space-4);
    }
    
    .language-selector {
        width: 100%;
        justify-content: center;
        margin-left: 0;
        padding-left: 0;
        border-left: none;
        border-top: 1px solid var(--color-border);
        padding-top: var(--space-3);
        margin-top: var(--space-3);
    }
    
    .section {
        padding: var(--space-16) 0;
    }
    
    .section-intro {
        margin-bottom: var(--space-10);
    }
    
    .problem-grid {
        grid-template-columns: 1fr;
    }
    
    .diagram-bottom {
        grid-template-columns: 1fr;
        gap: var(--space-3);
    }
    
    .diagram-engineer {
        transform: none;
        order: -1;
    }
    
    .roles-grid {
        grid-template-columns: 1fr;
    }
    
    .research-grid {
        grid-template-columns: 1fr;
    }
    
    .principles-grid {
        grid-template-columns: 1fr;
    }
    
    .maturity-level {
        flex-direction: column;
        align-items: center;
        text-align: center;
    }
    
    .footer-content {
        flex-direction: column;
        align-items: center;
        text-align: center;
        gap: var(--space-8);
    }
    
    .footer-brand {
        align-items: center;
    }
}

/* --------------------------------------------------------------------------
   Declaration Section
   -------------------------------------------------------------------------- */
.declaration-cards {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--space-6);
    margin-top: var(--space-12);
    max-width: 900px;
    margin-left: auto;
    margin-right: auto;
}

.declaration-card {
    display: grid;
    grid-template-columns: auto 1fr;
    gap: var(--space-6);
    align-items: flex-start;
    background-color: var(--color-bg-card);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: var(--space-8);
    transition: transform var(--transition-base), box-shadow var(--transition-base), border-color var(--transition-base);
}

.declaration-card:hover {
    border-color: var(--color-accent);
    transform: translateX(8px);
    box-shadow: 0 8px 24px rgba(59, 130, 246, 0.15);
}

.declaration-number {
    display: flex;
    align-items: center;
    justify-content: center;
    min-width: 48px;
    width: 48px;
    height: 48px;
    background: linear-gradient(135deg, var(--color-accent), #1e3a8a);
    border-radius: var(--radius-md);
    font-weight: var(--font-weight-bold);
    font-size: var(--font-size-lg);
    color: var(--color-text-primary);
    flex-shrink: 0;
}

.declaration-text {
    font-size: var(--font-size-base);
    line-height: var(--line-height-relaxed);
    color: var(--color-text-primary);
    margin: 0;
    padding-top: var(--space-1);
}

/* --------------------------------------------------------------------------
   Utility Classes
   -------------------------------------------------------------------------- */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}