/* =====================================================
   ChainSolution.net — Styles
   Modern, minimal, maker aesthetic
   ===================================================== */

/* CSS Custom Properties */
:root {
    /* Colors - Dark theme with cyan accent */
    --color-bg-primary: #0a0e14;
    --color-bg-secondary: #0f1419;
    --color-bg-tertiary: #151c24;
    --color-bg-card: #131920;
    --color-bg-card-hover: #1a232d;
    
    --color-accent: #00d4aa;
    --color-accent-light: #00ffcc;
    --color-accent-dim: rgba(0, 212, 170, 0.15);
    --color-accent-glow: rgba(0, 212, 170, 0.4);
    
    --color-text-primary: #e8edf3;
    --color-text-secondary: #8b99a8;
    --color-text-muted: #5a6775;
    
    --color-border: rgba(255, 255, 255, 0.08);
    --color-border-hover: rgba(0, 212, 170, 0.3);
    
    /* Typography */
    --font-display: 'Outfit', -apple-system, BlinkMacSystemFont, sans-serif;
    --font-mono: 'JetBrains Mono', 'SF Mono', Consolas, monospace;
    
    --text-xs: 0.75rem;
    --text-sm: 0.875rem;
    --text-base: 1rem;
    --text-lg: 1.125rem;
    --text-xl: 1.25rem;
    --text-2xl: 1.5rem;
    --text-3xl: 2rem;
    --text-4xl: 2.5rem;
    --text-5xl: 3.5rem;
    
    /* 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;
    
    /* Layout */
    --max-width: 1200px;
    --border-radius: 12px;
    --border-radius-lg: 20px;
    
    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-base: 250ms ease;
    --transition-slow: 400ms cubic-bezier(0.4, 0, 0.2, 1);
}

/* 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-display);
    font-size: var(--text-base);
    line-height: 1.6;
    color: var(--color-text-primary);
    background-color: var(--color-bg-primary);
    min-height: 100vh;
    overflow-x: hidden;
    position: relative;
}

/* Accessibility */
.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;
}

/* Focus states */
:focus-visible {
    outline: 2px solid var(--color-accent);
    outline-offset: 2px;
}

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

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

/* =====================================================
   Neural Network Background
   ===================================================== */

#neural-network-bg {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 0;
    pointer-events: auto;
    background: var(--color-bg-primary);
}

/* =====================================================
   Hero Section
   ===================================================== */

.hero {
    position: relative;
    z-index: 1;
    min-height: auto;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    padding: var(--space-3xl) var(--space-xl) var(--space-xl);
    text-align: center;
}

.hero-content {
    max-width: 800px;
    animation: fade-up 1s ease-out;
}

@keyframes fade-up {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.logo-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--space-md);
    margin-bottom: var(--space-lg);
}

.logo-icon {
    width: 60px;
    height: 60px;
    color: var(--color-accent);
    animation: pulse-glow 3s ease-in-out infinite;
}

@keyframes pulse-glow {
    0%, 100% { 
        filter: drop-shadow(0 0 20px var(--color-accent-glow));
        transform: scale(1);
    }
    50% { 
        filter: drop-shadow(0 0 40px var(--color-accent-glow));
        transform: scale(1.05);
    }
}

.site-title {
    font-family: var(--font-mono);
    font-size: var(--text-4xl);
    font-weight: 600;
    letter-spacing: -0.02em;
}

.site-title a {
    color: var(--color-text-primary);
    background: linear-gradient(135deg, var(--color-text-primary) 0%, var(--color-accent) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    text-decoration: none;
    transition: all var(--transition-base);
}

.site-title a:hover {
    background: linear-gradient(135deg, var(--color-accent-light) 0%, var(--color-accent) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.site-subtitle {
    font-size: 1.5em;
    margin: 1px 0 0;
    line-height: 1.1;
}

.site-subtitle a {
    color: inherit;
    text-decoration: none;
}

.hero-subtitle {
    font-size: var(--text-lg);
    font-weight: 500;
    color: var(--color-accent);
    margin-bottom: var(--space-md);
    letter-spacing: 0.02em;
}

.hero-intro {
    font-size: var(--text-base);
    color: var(--color-text-secondary);
    line-height: 1.6;
    margin-bottom: 0;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.hero-cta {
    display: inline-flex;
    align-items: center;
    gap: var(--space-sm);
    font-size: var(--text-sm);
    color: var(--color-text-muted);
    padding: var(--space-md) var(--space-lg);
    background: var(--color-bg-tertiary);
    border: 1px solid var(--color-border);
    border-radius: 100px;
    animation: fade-up 1s ease-out 0.3s both;
}

.cta-icon {
    font-size: var(--text-lg);
    animation: bounce-down 2s ease-in-out infinite;
}

@keyframes bounce-down {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(5px); }
}

/* Scroll indicator */
.scroll-indicator {
    display: none;
}

/* =====================================================
   Main Content / Solutions Section
   ===================================================== */

.main-content {
    position: relative;
    z-index: 1;
    padding: var(--space-xl) var(--space-xl) var(--space-3xl);
    background: linear-gradient(to bottom, transparent, var(--color-bg-secondary) 10%);
}

.solutions-section {
    max-width: var(--max-width);
    margin: 0 auto;
}

.section-title {
    font-family: var(--font-mono);
    font-size: var(--text-sm);
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.15em;
    color: var(--color-accent);
    margin-bottom: var(--space-2xl);
    display: flex;
    align-items: center;
    gap: var(--space-md);
}

.section-title::before {
    content: '';
    width: 40px;
    height: 2px;
    background: var(--color-accent);
}

/* Solutions Grid */
.solutions-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: var(--space-lg);
    margin-bottom: var(--space-xl);
}

/* Solution Card */
.solution-card {
    position: relative;
    background: var(--color-bg-card);
    border: 1px solid var(--color-border);
    border-radius: var(--border-radius);
    padding: var(--space-xl);
    transition: all var(--transition-slow);
    overflow: hidden;
    display: flex;
    flex-direction: column;
    animation: card-appear 0.6s ease-out both;
}

.solution-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--color-accent), transparent);
    opacity: 0;
    transition: opacity var(--transition-base);
}

.solution-card:hover {
    background: var(--color-bg-card-hover);
    border-color: var(--color-border-hover);
    transform: translateY(-4px);
    box-shadow: 
        0 20px 40px rgba(0, 0, 0, 0.3),
        0 0 60px var(--color-accent-dim);
}

.solution-card:hover::before {
    opacity: 1;
}

@keyframes card-appear {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Stagger animation for cards */
.solution-card:nth-child(1) { animation-delay: 0.1s; }
.solution-card:nth-child(2) { animation-delay: 0.15s; }
.solution-card:nth-child(3) { animation-delay: 0.2s; }
.solution-card:nth-child(4) { animation-delay: 0.25s; }
.solution-card:nth-child(5) { animation-delay: 0.3s; }
.solution-card:nth-child(6) { animation-delay: 0.35s; }
.solution-card:nth-child(7) { animation-delay: 0.4s; }
.solution-card:nth-child(8) { animation-delay: 0.45s; }
.solution-card:nth-child(9) { animation-delay: 0.5s; }
.solution-card:nth-child(n+10) { animation-delay: 0.55s; }

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

.card-title {
    font-size: var(--text-xl);
    font-weight: 600;
    color: var(--color-text-primary);
    line-height: 1.3;
}

.card-tag {
    font-family: var(--font-mono);
    font-size: var(--text-xs);
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--color-accent);
    background: var(--color-accent-dim);
    padding: var(--space-xs) var(--space-sm);
    border-radius: 4px;
    white-space: nowrap;
    flex-shrink: 0;
}

.card-description {
    font-size: var(--text-sm);
    color: var(--color-text-secondary);
    line-height: 1.7;
    margin-bottom: var(--space-lg);
    flex-grow: 1;
}

.card-action {
    display: inline-flex;
    align-items: center;
    gap: var(--space-sm);
    font-family: var(--font-mono);
    font-size: var(--text-sm);
    font-weight: 500;
    color: var(--color-accent);
    background: transparent;
    border: 1px solid var(--color-accent);
    border-radius: 8px;
    padding: var(--space-sm) var(--space-lg);
    cursor: pointer;
    transition: all var(--transition-base);
    text-decoration: none;
    align-self: flex-start;
}

.card-action:hover {
    background: var(--color-accent);
    color: var(--color-bg-primary);
    transform: translateX(4px);
}

.card-action-icon {
    transition: transform var(--transition-base);
}

.card-action:hover .card-action-icon {
    transform: translateX(4px);
}

/* Empty state */
.solutions-empty {
    text-align: center;
    padding: var(--space-4xl) var(--space-xl);
    color: var(--color-text-muted);
    font-size: var(--text-lg);
}

/* Loading spinner */
.loading-spinner {
    display: flex;
    justify-content: center;
    padding: var(--space-3xl);
}

.loading-spinner.hidden {
    display: none;
}

.spinner {
    width: 40px;
    height: 40px;
    border: 3px solid var(--color-border);
    border-top-color: var(--color-accent);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* =====================================================
   Featured Projects Section
   ===================================================== */

.featured-projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
    gap: var(--space-xl);
    margin-top: var(--space-xl);
}

.featured-project-card {
    position: relative;
    display: block;
    background: linear-gradient(135deg, var(--color-bg-card) 0%, var(--color-bg-tertiary) 100%);
    border: 1px solid var(--color-border);
    border-radius: var(--border-radius-lg);
    padding: var(--space-xl);
    transition: all var(--transition-slow);
    overflow: hidden;
    text-decoration: none;
    animation: card-appear 0.8s ease-out both;
}

.featured-project-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(135deg, var(--color-accent-dim) 0%, transparent 50%);
    opacity: 0;
    transition: opacity var(--transition-slow);
    pointer-events: none;
}

.featured-project-card::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, var(--color-accent), var(--color-accent-light));
    opacity: 0;
    transform: scaleX(0);
    transform-origin: left;
    transition: all var(--transition-slow);
}

.featured-project-card:hover {
    border-color: var(--color-accent);
    transform: translateY(-8px) scale(1.02);
    box-shadow:
        0 30px 60px rgba(0, 0, 0, 0.4),
        0 0 80px var(--color-accent-dim),
        inset 0 0 0 1px var(--color-accent-dim);
}

.featured-project-card:hover::before {
    opacity: 1;
}

.featured-project-card:hover::after {
    opacity: 1;
    transform: scaleX(1);
}

.featured-project-card:nth-child(1) {
    animation-delay: 0.2s;
}

.featured-project-card:nth-child(2) {
    animation-delay: 0.3s;
}

.featured-project-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--space-lg);
    margin-bottom: var(--space-lg);
    position: relative;
    z-index: 1;
}

.featured-project-logo {
    flex-shrink: 0;
    height: 50px;
    display: flex;
    align-items: center;
    filter: brightness(1.1) drop-shadow(0 4px 12px rgba(0, 212, 170, 0.2));
    transition: all var(--transition-slow);
}

.featured-project-card:hover .featured-project-logo {
    filter: brightness(1.3) drop-shadow(0 8px 24px rgba(0, 212, 170, 0.4));
    transform: scale(1.05);
}

.featured-project-logo img {
    height: 100%;
    width: auto;
    max-width: 100%;
    object-fit: contain;
}

.featured-project-badge {
    font-family: var(--font-mono);
    font-size: var(--text-xs);
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: var(--color-accent);
    background: var(--color-accent-dim);
    padding: var(--space-sm) var(--space-md);
    border-radius: 6px;
    border: 1px solid rgba(0, 212, 170, 0.2);
    white-space: nowrap;
    transition: all var(--transition-base);
}

.featured-project-card:hover .featured-project-badge {
    background: rgba(0, 212, 170, 0.25);
    border-color: var(--color-accent);
    color: var(--color-accent-light);
    transform: translateY(-2px);
}

.featured-project-content {
    position: relative;
    z-index: 1;
}

.featured-project-description {
    font-size: var(--text-sm);
    line-height: 1.7;
    color: var(--color-text-secondary);
    margin-bottom: var(--space-lg);
    transition: color var(--transition-base);
}

.featured-project-card:hover .featured-project-description {
    color: var(--color-text-primary);
}

.featured-project-footer {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--space-md);
    padding-top: var(--space-md);
    border-top: 1px solid var(--color-border);
    transition: border-color var(--transition-base);
}

.featured-project-card:hover .featured-project-footer {
    border-color: var(--color-accent-dim);
}

.featured-project-cta {
    font-family: var(--font-mono);
    font-size: var(--text-sm);
    font-weight: 600;
    color: var(--color-accent);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    transition: all var(--transition-base);
}

.featured-project-card:hover .featured-project-cta {
    color: var(--color-accent-light);
    letter-spacing: 0.1em;
}

.featured-project-arrow {
    font-size: var(--text-2xl);
    color: var(--color-accent);
    transition: all var(--transition-slow);
    line-height: 1;
}

.featured-project-card:hover .featured-project-arrow {
    transform: translateX(8px);
    color: var(--color-accent-light);
}

/* Add decorative elements */
.featured-project-card::before {
    content: '';
    position: absolute;
    top: 50%;
    right: -100px;
    width: 300px;
    height: 300px;
    background: radial-gradient(circle, var(--color-accent-glow) 0%, transparent 70%);
    opacity: 0;
    transform: translate(0, -50%);
    transition: opacity var(--transition-slow);
    pointer-events: none;
}

.featured-project-card:hover::before {
    opacity: 0.3;
}

/* =====================================================
   Footer
   ===================================================== */

.footer {
    position: relative;
    z-index: 1;
    background: var(--color-bg-secondary);
    border-top: 1px solid var(--color-border);
    padding: var(--space-xl) var(--space-xl) var(--space-lg);
}

.footer-content {
    max-width: var(--max-width);
    margin: 0 auto;
    display: flex;
    flex-wrap: wrap;
    justify-content: space-between;
    align-items: center;
    gap: var(--space-lg);
}

.footer-brand {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    font-family: var(--font-mono);
    font-size: var(--text-sm);
    color: var(--color-text-muted);
}

.footer-logo {
    font-size: var(--text-xl);
    color: var(--color-accent);
}

.footer-controls {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: var(--space-xl);
}

/* Language selector */
.language-selector {
    position: relative;
}

.select-wrapper {
    position: relative;
    display: inline-flex;
    align-items: center;
}

.select-wrapper select {
    appearance: none;
    font-family: var(--font-display);
    font-size: var(--text-sm);
    color: var(--color-text-secondary);
    background: var(--color-bg-tertiary);
    border: 1px solid var(--color-border);
    border-radius: 8px;
    padding: var(--space-sm) var(--space-2xl) var(--space-sm) var(--space-md);
    cursor: pointer;
    transition: all var(--transition-base);
}

.select-wrapper select:hover {
    border-color: var(--color-border-hover);
    color: var(--color-text-primary);
}

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

.select-icon {
    position: absolute;
    right: var(--space-md);
    color: var(--color-text-muted);
    pointer-events: none;
    font-size: var(--text-xs);
}

/* Footer links */
.footer-links {
    display: flex;
    align-items: center;
    gap: var(--space-md);
}

.footer-link {
    font-size: var(--text-sm);
    color: var(--color-text-muted);
    transition: color var(--transition-fast);
}

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

.footer-divider {
    color: var(--color-border);
}

/* Footer bottom */
.footer-bottom {
    max-width: var(--max-width);
    margin: var(--space-lg) auto 0;
    padding-top: var(--space-md);
    border-top: 1px solid var(--color-border);
}

.copyright {
    font-size: var(--text-xs);
    color: var(--color-text-muted);
    text-align: center;
}

/* =====================================================
   Responsive Design
   ===================================================== */

@media (max-width: 768px) {
    :root {
        --text-4xl: 2rem;
        --text-3xl: 1.75rem;
        --text-xl: 1.125rem;
    }
    
    .hero {
        padding: var(--space-xl) var(--space-md) var(--space-lg);
        min-height: auto;
    }

    .logo-container {
        margin-bottom: var(--space-md);
    }

    .logo-icon {
        width: 50px;
        height: 50px;
    }

    .site-title {
        font-size: var(--text-3xl);
    }

    .hero-intro {
        font-size: var(--text-sm);
    }

    .main-content {
        padding: var(--space-lg) var(--space-md) var(--space-2xl);
    }
    
    .solutions-grid {
        grid-template-columns: 1fr;
        gap: var(--space-md);
    }
    
    .solution-card {
        padding: var(--space-lg);
    }

    /* Featured Projects - Mobile */
    .featured-projects-grid {
        grid-template-columns: 1fr;
        gap: var(--space-md);
        margin-top: var(--space-md);
    }

    .featured-project-card {
        padding: var(--space-md);
    }

    .featured-project-header {
        flex-direction: column;
        align-items: flex-start;
        gap: var(--space-sm);
        margin-bottom: var(--space-md);
    }

    .featured-project-logo {
        height: 40px;
    }

    .featured-project-badge {
        align-self: flex-start;
    }

    .featured-project-description {
        font-size: var(--text-xs);
        margin-bottom: var(--space-md);
    }

    .footer-content {
        flex-direction: column;
        text-align: center;
    }
    
    .footer-controls {
        flex-direction: column;
        gap: var(--space-lg);
    }
}

@media (max-width: 480px) {
    .card-header {
        flex-direction: column;
        gap: var(--space-sm);
    }
    
    .card-tag {
        align-self: flex-start;
    }
}

/* =====================================================
   Print Styles
   ===================================================== */

@media print {
    #neural-network-bg,
    .scroll-indicator {
        display: none;
    }

    body {
        background: white;
        color: black;
    }

    .solution-card,
    .featured-project-card {
        break-inside: avoid;
        border: 1px solid #ccc;
    }
}

/* =====================================================
   Reduced Motion
   ===================================================== */

@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
    
    html {
        scroll-behavior: auto;
    }
}