/* ============================================
   ScaleSpark.io — Design System & Styles
   ============================================ */

/* --- Design Tokens --- */
:root {
    /* Colors */
    --color-bg: #0a0a0f;
    --color-bg-elevated: #111118;
    --color-bg-card: #16161f;
    --color-bg-card-hover: #1c1c28;
    --color-border: rgba(255, 255, 255, 0.06);
    --color-border-hover: rgba(255, 255, 255, 0.12);
    
    --color-text: #e8e8ed;
    --color-text-secondary: #8b8b9e;
    --color-text-muted: #5a5a6e;
    
    --color-accent: #6c5ce7;
    --color-accent-light: #a29bfe;
    --color-accent-glow: rgba(108, 92, 231, 0.3);
    
    --color-spark: #f39c12;
    --color-spark-light: #f9ca24;
    --color-spark-glow: rgba(243, 156, 18, 0.25);
    
    --color-success: #00d2d3;
    --color-success-glow: rgba(0, 210, 211, 0.2);

    --gradient-primary: linear-gradient(135deg, #6c5ce7 0%, #a29bfe 50%, #f39c12 100%);
    --gradient-spark: linear-gradient(135deg, #f39c12 0%, #f9ca24 50%, #6c5ce7 100%);
    --gradient-glow: radial-gradient(ellipse at center, var(--color-accent-glow) 0%, transparent 70%);
    
    /* Typography */
    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-mono: 'JetBrains 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;
    
    /* Radius */
    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 16px;
    --radius-xl: 24px;
    --radius-full: 9999px;
    
    /* Transitions */
    --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
    --ease-spring: cubic-bezier(0.34, 1.56, 0.64, 1);
    --duration-fast: 150ms;
    --duration-normal: 300ms;
    --duration-slow: 500ms;
}

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

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

body {
    font-family: var(--font-sans);
    background: var(--color-bg);
    color: var(--color-text);
    line-height: 1.6;
    overflow-x: hidden;
    position: relative;
}

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

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

/* --- Animated Background --- */
.bg-grid {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 0;
    pointer-events: none;
    background-image: 
        linear-gradient(rgba(255,255,255,0.02) 1px, transparent 1px),
        linear-gradient(90deg, rgba(255,255,255,0.02) 1px, transparent 1px);
    background-size: 60px 60px;
    mask-image: radial-gradient(ellipse 80% 60% at 50% 30%, black 30%, transparent 100%);
    -webkit-mask-image: radial-gradient(ellipse 80% 60% at 50% 30%, black 30%, transparent 100%);
}

.bg-glow {
    position: fixed;
    border-radius: 50%;
    filter: blur(120px);
    z-index: 0;
    pointer-events: none;
    animation: glow-drift 20s ease-in-out infinite;
}

.bg-glow-1 {
    width: 600px;
    height: 600px;
    background: var(--color-accent-glow);
    top: -200px;
    right: -100px;
    opacity: 0.4;
}

.bg-glow-2 {
    width: 500px;
    height: 500px;
    background: var(--color-spark-glow);
    bottom: -150px;
    left: -100px;
    opacity: 0.3;
    animation-delay: -7s;
}

.bg-glow-3 {
    width: 400px;
    height: 400px;
    background: var(--color-success-glow);
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    opacity: 0.15;
    animation-delay: -14s;
}

@keyframes glow-drift {
    0%, 100% { transform: translate(0, 0) scale(1); }
    25% { transform: translate(30px, -20px) scale(1.05); }
    50% { transform: translate(-20px, 30px) scale(0.95); }
    75% { transform: translate(20px, 20px) scale(1.02); }
}

/* --- Container --- */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--space-xl);
    position: relative;
    z-index: 1;
}

/* --- Navigation --- */
.nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 100;
    padding: var(--space-lg) 0;
    transition: all var(--duration-normal) var(--ease-out);
}

.nav.scrolled {
    padding: var(--space-sm) 0;
    background: rgba(10, 10, 15, 0.85);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--color-border);
}

.nav-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    font-weight: 700;
    font-size: 1.25rem;
    z-index: 101;
}

.logo-icon {
    font-size: 1.5rem;
    filter: drop-shadow(0 0 8px var(--color-spark-glow));
}

.logo-accent {
    background: var(--gradient-spark);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

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

.nav-link {
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--color-text-secondary);
    transition: color var(--duration-fast);
    position: relative;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--gradient-primary);
    transition: width var(--duration-normal) var(--ease-out);
    border-radius: 1px;
}

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

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

.cta-link {
    color: var(--color-bg) !important;
    background: var(--gradient-primary);
    padding: var(--space-sm) var(--space-lg);
    border-radius: var(--radius-full);
    font-weight: 600;
    transition: all var(--duration-normal) var(--ease-out);
}

.cta-link::after {
    display: none;
}

.cta-link:hover {
    transform: translateY(-1px);
    box-shadow: 0 8px 24px var(--color-accent-glow);
}

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
    z-index: 101;
}

.nav-toggle span {
    width: 24px;
    height: 2px;
    background: var(--color-text);
    border-radius: 2px;
    transition: all var(--duration-normal) var(--ease-out);
}

/* --- Hero --- */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    padding-top: 100px;
    position: relative;
}

.hero .container {
    text-align: center;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: var(--space-sm);
    padding: var(--space-sm) var(--space-lg);
    background: rgba(108, 92, 231, 0.1);
    border: 1px solid rgba(108, 92, 231, 0.2);
    border-radius: var(--radius-full);
    font-size: 0.8rem;
    font-weight: 500;
    color: var(--color-accent-light);
    letter-spacing: 0.5px;
    text-transform: uppercase;
    margin-bottom: var(--space-2xl);
}

.badge-dot {
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: var(--color-accent-light);
    animation: pulse-dot 2s ease-in-out infinite;
}

@keyframes pulse-dot {
    0%, 100% { opacity: 1; box-shadow: 0 0 0 0 rgba(162, 155, 254, 0.4); }
    50% { opacity: 0.7; box-shadow: 0 0 0 6px rgba(162, 155, 254, 0); }
}

.hero-title {
    font-size: clamp(2.5rem, 6vw, 4.5rem);
    font-weight: 800;
    line-height: 1.1;
    letter-spacing: -0.03em;
    margin-bottom: var(--space-xl);
}

.hero-gradient {
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: clamp(1rem, 2vw, 1.25rem);
    color: var(--color-text-secondary);
    max-width: 680px;
    margin: 0 auto var(--space-2xl);
    line-height: 1.7;
}

.hero-subtitle strong {
    color: var(--color-text);
    font-weight: 600;
}

.hero-actions {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-lg);
    margin-bottom: var(--space-4xl);
    flex-wrap: wrap;
}

/* --- Buttons --- */
.btn {
    display: inline-flex;
    align-items: center;
    gap: var(--space-sm);
    padding: 14px 28px;
    border-radius: var(--radius-full);
    font-weight: 600;
    font-size: 0.95rem;
    transition: all var(--duration-normal) var(--ease-out);
    cursor: pointer;
    border: none;
    font-family: var(--font-sans);
    white-space: nowrap;
}

.btn-primary {
    background: var(--gradient-primary);
    color: white;
    box-shadow: 0 4px 16px var(--color-accent-glow);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 32px var(--color-accent-glow);
}

.btn-primary:active {
    transform: translateY(0);
}

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

.btn-ghost:hover {
    color: var(--color-text);
    border-color: var(--color-border-hover);
    background: rgba(255, 255, 255, 0.03);
}

.btn-lg {
    padding: 18px 36px;
    font-size: 1.05rem;
}

/* --- Stats --- */
.hero-stats {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2xl);
    flex-wrap: wrap;
}

.stat {
    text-align: center;
}

.stat-value {
    display: block;
    font-size: 2rem;
    font-weight: 800;
    letter-spacing: -0.02em;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.stat-label {
    font-size: 0.8rem;
    color: var(--color-text-muted);
    text-transform: uppercase;
    letter-spacing: 1px;
    font-weight: 500;
    margin-top: 4px;
}

.stat-divider {
    width: 1px;
    height: 40px;
    background: var(--color-border);
}

/* --- Scroll Indicator --- */
.hero-scroll {
    position: absolute;
    bottom: 40px;
    left: 50%;
    transform: translateX(-50%);
}

.scroll-indicator {
    width: 24px;
    height: 40px;
    border: 2px solid var(--color-border-hover);
    border-radius: 12px;
    position: relative;
}

.scroll-indicator::after {
    content: '';
    position: absolute;
    top: 8px;
    left: 50%;
    transform: translateX(-50%);
    width: 3px;
    height: 8px;
    background: var(--color-accent-light);
    border-radius: 2px;
    animation: scroll-bounce 2s ease-in-out infinite;
}

@keyframes scroll-bounce {
    0%, 100% { top: 8px; opacity: 1; }
    50% { top: 20px; opacity: 0.3; }
}

/* --- Social Proof Bar --- */
.proof-bar {
    padding: var(--space-2xl) 0;
    border-top: 1px solid var(--color-border);
    border-bottom: 1px solid var(--color-border);
    background: rgba(22, 22, 31, 0.5);
}

.proof-text {
    text-align: center;
    font-size: 0.85rem;
    color: var(--color-text-muted);
    letter-spacing: 1px;
    text-transform: uppercase;
    font-weight: 500;
}

/* --- Sections --- */
.section {
    padding: var(--space-4xl) 0;
}

.section-header {
    text-align: center;
    max-width: 700px;
    margin: 0 auto var(--space-3xl);
}

.section-tag {
    display: inline-block;
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--color-accent-light);
    letter-spacing: 2px;
    text-transform: uppercase;
    margin-bottom: var(--space-md);
    padding: var(--space-xs) var(--space-lg);
    background: rgba(108, 92, 231, 0.08);
    border: 1px solid rgba(108, 92, 231, 0.15);
    border-radius: var(--radius-full);
}

.section-title {
    font-size: clamp(1.8rem, 4vw, 2.8rem);
    font-weight: 800;
    letter-spacing: -0.02em;
    line-height: 1.2;
    margin-bottom: var(--space-lg);
}

.text-gradient {
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.section-desc {
    font-size: 1.05rem;
    color: var(--color-text-secondary);
    line-height: 1.7;
}

/* --- Services --- */
.services-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--space-xl);
}

.service-card {
    background: var(--color-bg-card);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: var(--space-2xl);
    transition: all var(--duration-normal) var(--ease-out);
    position: relative;
    overflow: hidden;
}

.service-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 2px;
    background: var(--gradient-primary);
    opacity: 0;
    transition: opacity var(--duration-normal);
}

.service-card:hover {
    border-color: var(--color-border-hover);
    background: var(--color-bg-card-hover);
    transform: translateY(-4px);
    box-shadow: 0 16px 48px rgba(0, 0, 0, 0.3);
}

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

.service-card-featured {
    grid-column: 1 / -1;
    display: grid;
    grid-template-columns: auto 1fr;
    grid-template-rows: auto auto 1fr;
    gap: 0 var(--space-xl);
}

.service-card-featured .service-icon {
    grid-row: 1 / 3;
}

.service-card-featured .service-features {
    grid-column: 1 / -1;
}

.service-icon {
    width: 56px;
    height: 56px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(108, 92, 231, 0.1);
    border: 1px solid rgba(108, 92, 231, 0.15);
    border-radius: var(--radius-md);
    margin-bottom: var(--space-lg);
    color: var(--color-accent-light);
}

.service-title {
    font-size: 1.15rem;
    font-weight: 700;
    margin-bottom: var(--space-sm);
    letter-spacing: -0.01em;
}

.service-desc {
    font-size: 0.9rem;
    color: var(--color-text-secondary);
    line-height: 1.6;
    margin-bottom: var(--space-lg);
}

.service-features {
    list-style: none;
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-sm);
}

.service-features li {
    font-size: 0.78rem;
    color: var(--color-text-muted);
    padding: 4px 12px;
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-full);
}

/* --- Results --- */
.results-section {
    background: var(--color-bg-elevated);
    border-top: 1px solid var(--color-border);
    border-bottom: 1px solid var(--color-border);
}

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

.result-card {
    background: var(--color-bg-card);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: var(--space-2xl);
    transition: all var(--duration-normal) var(--ease-out);
    position: relative;
}

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

.result-number {
    font-size: 3rem;
    font-weight: 900;
    letter-spacing: -0.03em;
    line-height: 1;
    margin-bottom: var(--space-sm);
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.result-title {
    font-size: 1.1rem;
    font-weight: 700;
    margin-bottom: var(--space-md);
}

.result-desc {
    font-size: 0.9rem;
    color: var(--color-text-secondary);
    line-height: 1.6;
    margin-bottom: var(--space-lg);
}

.result-tag {
    display: inline-block;
    font-size: 0.7rem;
    font-weight: 600;
    color: var(--color-spark);
    letter-spacing: 1px;
    text-transform: uppercase;
    padding: 4px 12px;
    background: rgba(243, 156, 18, 0.08);
    border: 1px solid rgba(243, 156, 18, 0.15);
    border-radius: var(--radius-full);
}

/* --- How It Works (Architecture) --- */
.architecture {
    max-width: 700px;
    margin: 0 auto;
}

.arch-layer {
    display: flex;
    gap: var(--space-xl);
    padding: var(--space-2xl);
    background: var(--color-bg-card);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    transition: all var(--duration-normal) var(--ease-out);
    position: relative;
}

.arch-layer:hover {
    border-color: var(--color-border-hover);
    background: var(--color-bg-card-hover);
}

.arch-number {
    font-size: 3rem;
    font-weight: 900;
    line-height: 1;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    flex-shrink: 0;
    opacity: 0.4;
}

.arch-title {
    font-size: 1.2rem;
    font-weight: 700;
    margin-bottom: 2px;
}

.arch-subtitle {
    font-size: 0.8rem;
    color: var(--color-accent-light);
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: var(--space-md);
}

.arch-desc {
    font-size: 0.9rem;
    color: var(--color-text-secondary);
    line-height: 1.6;
    margin-bottom: var(--space-md);
}

.arch-tags {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-sm);
}

.arch-tag {
    font-size: 0.72rem;
    font-family: var(--font-mono);
    color: var(--color-text-muted);
    padding: 3px 10px;
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
}

.arch-connector {
    width: 2px;
    height: 32px;
    background: linear-gradient(to bottom, var(--color-border), transparent);
    margin: 0 auto;
}

/* --- Tech Stack --- */
.tech-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--space-xl);
}

.tech-category {
    background: var(--color-bg-card);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: var(--space-xl);
    transition: all var(--duration-normal) var(--ease-out);
}

.tech-category:hover {
    border-color: var(--color-border-hover);
}

.tech-cat-title {
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--color-accent-light);
    letter-spacing: 1.5px;
    text-transform: uppercase;
    margin-bottom: var(--space-lg);
    padding-bottom: var(--space-md);
    border-bottom: 1px solid var(--color-border);
}

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

.tech-item {
    font-size: 0.85rem;
    color: var(--color-text-secondary);
    padding: var(--space-sm) 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.03);
    transition: color var(--duration-fast);
}

.tech-item:last-child {
    border-bottom: none;
}

.tech-item:hover {
    color: var(--color-text);
}

/* --- CTA Section --- */
.cta-section {
    padding: var(--space-4xl) 0;
}

.cta-card {
    text-align: center;
    padding: var(--space-4xl) var(--space-2xl);
    background: var(--color-bg-card);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-xl);
    position: relative;
    overflow: hidden;
}

.cta-glow {
    position: absolute;
    top: -200px;
    left: 50%;
    transform: translateX(-50%);
    width: 600px;
    height: 400px;
    background: radial-gradient(ellipse, var(--color-accent-glow) 0%, transparent 70%);
    pointer-events: none;
    opacity: 0.5;
}

.cta-title {
    font-size: clamp(1.8rem, 4vw, 2.5rem);
    font-weight: 800;
    letter-spacing: -0.02em;
    line-height: 1.2;
    margin: var(--space-lg) 0;
    position: relative;
}

.cta-desc {
    font-size: 1.05rem;
    color: var(--color-text-secondary);
    max-width: 560px;
    margin: 0 auto var(--space-2xl);
    line-height: 1.7;
    position: relative;
}

.cta-actions {
    position: relative;
    margin-bottom: var(--space-lg);
}

.cta-note {
    font-size: 0.8rem;
    color: var(--color-text-muted);
    position: relative;
}

/* --- Footer --- */
.footer {
    padding: var(--space-2xl) 0;
    border-top: 1px solid var(--color-border);
}

.footer-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

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

.footer-copy {
    font-size: 0.8rem;
    color: var(--color-text-muted);
}

.footer-links {
    display: flex;
    gap: var(--space-lg);
}

.footer-link {
    font-size: 0.85rem;
    color: var(--color-text-secondary);
    transition: color var(--duration-fast);
}

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

/* --- Animations --- */
.animate-in {
    opacity: 0;
    transform: translateY(24px);
    transition: opacity var(--duration-slow) var(--ease-out), 
                transform var(--duration-slow) var(--ease-out);
    transition-delay: var(--delay, 0s);
}

.animate-in.visible {
    opacity: 1;
    transform: translateY(0);
}

/* --- Responsive --- */
@media (max-width: 1024px) {
    .services-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .service-card-featured {
        grid-column: 1 / -1;
    }
    
    .tech-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    .nav-links {
        position: fixed;
        top: 0;
        right: -100%;
        width: 80%;
        max-width: 320px;
        height: 100vh;
        background: var(--color-bg-elevated);
        border-left: 1px solid var(--color-border);
        flex-direction: column;
        align-items: flex-start;
        padding: 100px var(--space-2xl) var(--space-2xl);
        gap: var(--space-lg);
        transition: right var(--duration-normal) var(--ease-out);
    }
    
    .nav-links.open {
        right: 0;
    }
    
    .nav-toggle {
        display: flex;
    }
    
    .nav-toggle.active span:nth-child(1) {
        transform: rotate(45deg) translate(5px, 5px);
    }
    .nav-toggle.active span:nth-child(2) {
        opacity: 0;
    }
    .nav-toggle.active span:nth-child(3) {
        transform: rotate(-45deg) translate(5px, -5px);
    }
    
    .services-grid,
    .results-grid {
        grid-template-columns: 1fr;
    }
    
    .service-card-featured {
        display: block;
    }
    
    .tech-grid {
        grid-template-columns: 1fr;
    }
    
    .hero-stats {
        gap: var(--space-xl);
    }
    
    .stat-divider {
        display: none;
    }
    
    .hero-actions {
        flex-direction: column;
    }
    
    .footer-inner {
        flex-direction: column;
        gap: var(--space-lg);
        text-align: center;
    }
    
    .arch-layer {
        flex-direction: column;
        gap: var(--space-md);
    }
    
    .arch-number {
        font-size: 2rem;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 var(--space-lg);
    }
    
    .hero {
        padding-top: 80px;
    }
    
    .section {
        padding: var(--space-3xl) 0;
    }
}