:root {
  /* Color Palette - Premium, Refined Dark Theme */
  --bg-primary: #000000; /* Pure black foundation */
  --bg-secondary: #0a0a0a;
  --bg-tertiary: #111111;
  
  /* Subtle, sophisticated accents */
  --accent-primary: #f8fafc; /* Crisp White */
  --accent-secondary: #94a3b8; /* Slate */
  
  /* Refined Typography Colors */
  --text-primary: #ffffff;
  --text-secondary: #a1a1aa; /* Zinc 400 */
  --text-tertiary: #71717a; /* Zinc 500 */
  
  /* Precise Borders and Surfaces */
  --border-color: rgba(255, 255, 255, 0.1);
  --border-hover: rgba(255, 255, 255, 0.2);
  --surface-base: rgba(255, 255, 255, 0.03);
  --surface-raised: rgba(255, 255, 255, 0.05);

  /* Typography */
  --font-main: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  
  /* Layout */
  --max-width: 1080px;
  --nav-height: 80px;

  /* Animation */
  --transition-fast: 0.1s ease-out;
  --transition-normal: 0.3s cubic-bezier(0.16, 1, 0.3, 1);
  --transition-slow: 0.6s cubic-bezier(0.16, 1, 0.3, 1);
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
  text-rendering: optimizeLegibility;
}

body {
  font-family: var(--font-main);
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  font-weight: 400;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

ul {
  list-style: none;
}

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

/* Typography Utilities */
h1, h2, h3, h4, h5, h6 {
  line-height: 1.15;
  font-weight: 500;
  letter-spacing: -0.04em;
  color: var(--text-primary);
}

.text-gradient {
  background: linear-gradient(180deg, #FFFFFF 0%, #A1A1AA 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  color: transparent;
}

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

/* Layout Utilities */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

.section {
  padding: 120px 0;
  position: relative;
}

@media (max-width: 768px) {
  .section {
    padding: 80px 0;
  }
}

/* Base Surfaces (Replacing generic glassmorphism) */
.surface {
  background: var(--surface-base);
  border: 1px solid var(--border-color);
  border-radius: 16px;
  transition: background var(--transition-normal), border-color var(--transition-normal);
}

.surface:hover {
  background: var(--surface-raised);
  border-color: var(--border-hover);
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 10px 20px;
  border-radius: 6px;
  font-weight: 500;
  font-size: 0.9rem;
  letter-spacing: 0;
  cursor: pointer;
  transition: all var(--transition-normal);
  border: 1px solid transparent;
  outline: none;
  gap: 8px;
}

.btn-primary {
  background: var(--text-primary);
  color: var(--bg-primary);
  box-shadow: 0 2px 8px rgba(255, 255, 255, 0.05);
}

.btn-primary:hover {
  background: #e4e4e7;
  transform: scale(0.98);
}

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

.btn-secondary:hover {
  background: var(--surface-base);
  border-color: var(--border-hover);
}

/* Navigation - Clean & Minimal */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: var(--nav-height);
  z-index: 1000;
  transition: background var(--transition-normal), backdrop-filter var(--transition-normal), border-bottom var(--transition-normal);
  display: flex;
  align-items: center;
  background: transparent;
  border-bottom: 1px solid transparent;
}

.navbar.scrolled {
  background: rgba(0, 0, 0, 0.7);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-color);
}

.nav-container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  width: 100%;
}

.logo {
  display: flex;
  align-items: center;
}

.logo-img {
  height: 90px;
  width: auto;
  object-fit: contain;
  display: block;
}

@media (max-width: 768px) {
  .logo-img {
    height: 70px;
  }
}

.nav-links {
  display: flex;
  gap: 40px;
  align-items: center;
}

.nav-link {
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--text-secondary);
  transition: color var(--transition-fast);
}

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

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 6px;
  cursor: pointer;
  background: none;
  border: none;
  padding: 8px;
}

.nav-toggle span {
  width: 24px;
  height: 2px;
  background: var(--text-primary);
  transition: transform 0.3s ease, opacity 0.3s ease;
  border-radius: 2px;
  transform-origin: center;
}

@media (max-width: 768px) {
  .nav-links {
    position: fixed;
    top: var(--nav-height);
    left: 0;
    width: 100%;
    height: calc(100vh - var(--nav-height));
    background: rgba(9, 9, 11, 0.95);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    flex-direction: column;
    justify-content: center;
    gap: 2.5rem;
    transform: translateX(100%);
    transition: transform var(--transition-normal);
    z-index: 999;
  }
  
  .nav-links.active {
    transform: translateX(0);
  }
  
  .nav-link {
    font-size: 1.25rem;
  }
  
  .nav-toggle {
    display: flex;
    z-index: 1000;
  }
  
  .nav-toggle.active span:nth-child(1) {
    transform: translateY(8px) rotate(45deg);
  }
  
  .nav-toggle.active span:nth-child(2) {
    opacity: 0;
  }
  
  .nav-toggle.active span:nth-child(3) {
    transform: translateY(-8px) rotate(-45deg);
  }
}

/* Sophisticated Background Effects */
.bg-glow {
  position: absolute;
  border-radius: 50%;
  filter: blur(120px);
  z-index: -1;
  opacity: 0.15;
  pointer-events: none;
}

/* Animations */
.animate-on-scroll {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity var(--transition-slow), transform var(--transition-slow);
}

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

/* --- Section Specific Styles --- */

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

.section-title {
    font-size: clamp(2.5rem, 5vw, 4rem);
    margin-bottom: 16px;
    letter-spacing: -0.05em;
    line-height: 1.05;
    font-weight: 500;
}

.section-desc {
    font-size: clamp(1rem, 2vw, 1.15rem);
    color: var(--text-secondary);
    max-width: 540px;
    margin: 0 auto 60px auto;
    line-height: 1.5;
}

/* Hero Section */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    padding-top: var(--nav-height);
    overflow: hidden;
}

.hero-container {
    display: grid;
    grid-template-columns: 1.2fr 0.8fr;
    gap: 80px;
    align-items: center;
}

.badge {
    display: inline-flex;
    align-items: center;
    padding: 6px 14px;
    border-radius: 6px;
    font-size: 0.8rem;
    font-weight: 500;
    color: var(--text-secondary);
    background: transparent;
    border: 1px solid var(--border-color);
    margin-bottom: 32px;
}

.hero-title {
    font-size: clamp(3rem, 7vw, 5.5rem);
    margin-bottom: 24px;
    line-height: 1.0;
    letter-spacing: -0.06em;
    font-weight: 500;
}

.hero-subtitle {
    font-size: clamp(1.1rem, 2.5vw, 1.2rem);
    color: var(--text-secondary);
    margin-bottom: 48px;
    max-width: 500px;
    line-height: 1.5;
}

.hero-cta {
    display: flex;
    gap: 16px;
    flex-wrap: wrap;
}

/* Refined Phone Mockup - Minimalist */
.phone-mockup {
    width: 100%;
    max-width: 320px;
    aspect-ratio: 19.5 / 40;
    border-radius: 36px;
    padding: 8px;
    position: relative;
    margin: 0 auto;
    background: #111111;
    border: 1px solid rgba(255,255,255,0.08);
    box-shadow: 
        0 30px 60px -15px rgba(0, 0, 0, 1),
        inset 0 0 0 1px rgba(255,255,255,0.02);
}

.phone-mockup::after {
    content: '';
    position: absolute;
    bottom: 8px;
    left: 50%;
    transform: translateX(-50%);
    width: 100px;
    height: 4px;
    border-radius: 4px;
    background: rgba(255, 255, 255, 0.15);
    z-index: 20;
}

.phone-screen {
    width: 100%;
    height: 100%;
    border-radius: 28px;
    background-color: var(--bg-primary);
    overflow: hidden;
    position: relative;
    padding: 30px 16px 16px;
    border: 1px solid rgba(255,255,255,0.02);
}

.app-ui-placeholder {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.task-card {
    padding: 12px 14px;
    border-radius: 8px;
    display: flex;
    gap: 12px;
    align-items: center;
    background: var(--surface-base);
    border: 1px solid transparent;
}

.task-icon {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    flex-shrink: 0;
}

.bg-indigo { background: #ffffff; }
.bg-pink { background: var(--text-secondary); }

.task-info h4 { font-size: 0.85rem; margin-bottom: 2px; font-weight: 500; }
.task-info p { font-size: 0.70rem; color: var(--text-tertiary); }

@media (max-width: 1024px) {
    .hero-container {
        grid-template-columns: 1fr;
        text-align: center;
        gap: 60px;
    }
    .hero-subtitle {
        margin: 0 auto 48px auto;
    }
    .hero-cta {
        justify-content: center;
    }
    .phone-mockup {
        max-width: 280px;
    }
}

/* Features Section */
.features-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
}

@media (max-width: 1024px) {
    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    .features-grid {
        grid-template-columns: 1fr;
    }
}

.feature-card {
    padding: 32px 24px;
    display: flex;
    flex-direction: column;
    align-items: flex-start;
}

.feature-icon {
    width: 48px;
    height: 48px;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 32px;
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
}

.feature-card h3 {
    font-size: 1.25rem;
    margin-bottom: 12px;
    font-weight: 600;
}

.feature-card p {
    color: var(--text-secondary);
    line-height: 1.6;
    font-size: 0.95rem;
}

/* How It Works Section */
.how-it-works-content {
    display: grid;
    grid-template-columns: 1.2fr 0.8fr;
    gap: 80px;
    align-items: center;
}

.steps-list {
    display: flex;
    flex-direction: column;
    gap: 48px;
    margin-top: 48px;
}

.step-item {
    display: flex;
    gap: 32px;
    position: relative;
}

.step-item:not(:last-child)::after {
    content: '';
    position: absolute;
    left: 20px;
    top: 50px;
    height: calc(100% - 20px);
    width: 1px;
    background: var(--border-color);
}

.step-number {
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--text-primary);
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    width: 40px;
    height: 40px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    z-index: 2;
}

.step-text h4 {
    font-size: 1.15rem;
    margin-bottom: 8px;
    color: var(--text-primary);
    padding-top: 6px;
}

.step-text p {
    color: var(--text-secondary);
    line-height: 1.6;
    font-size: 0.95rem;
}

.stats-card {
    padding: 48px;
    display: flex;
    flex-direction: column;
    gap: 40px;
}

.stat {
    display: flex;
    flex-direction: column;
}

.stat-number {
    font-size: clamp(2.5rem, 5vw, 3rem);
    font-weight: 600;
    letter-spacing: -0.05em;
    line-height: 1;
    margin-bottom: 12px;
}

.stat-label {
    color: var(--text-secondary);
    font-weight: 500;
    font-size: 0.85rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

@media (max-width: 1024px) {
    .how-it-works-content {
        grid-template-columns: 1fr;
        gap: 60px;
    }
    .stats-card {
        padding: 32px;
        flex-direction: row;
        flex-wrap: wrap;
        gap: 24px;
        justify-content: space-between;
    }
    .stat {
        flex: 1 1 45%;
    }
}

@media (max-width: 600px) {
    .stats-card {
        flex-direction: column;
        text-align: center;
    }
    .step-item::after {
        display: none;
    }
}

/* Footer Section */
.footer {
    background: var(--bg-primary);
    padding: 100px 0 40px 0;
    border-top: 1px solid var(--border-color);
}

.footer-container {
    display: grid;
    grid-template-columns: 1fr 2fr;
    gap: 80px;
    margin-bottom: 80px;
}

.footer-brand .logo-img {
    margin-bottom: 24px;
}

.footer-links {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 40px;
}

.link-group h4 {
    color: var(--text-primary);
    margin-bottom: 24px;
    font-size: 0.95rem;
    font-weight: 500;
}

.link-group ul {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.link-group a {
    color: var(--text-secondary);
    font-size: 0.95rem;
}

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

.footer-bottom {
    display: flex;
    justify-content: space-between;
    align-items: center;
    color: var(--text-tertiary);
    font-size: 0.85rem;
    border-top: 1px solid var(--border-color);
    padding-top: 40px;
}

@media (max-width: 768px) {
    .footer {
        padding: 60px 0 30px 0;
    }
    .footer-container {
        grid-template-columns: 1fr;
        gap: 40px;
        margin-bottom: 40px;
    }
    .footer-links {
        grid-template-columns: 1fr 1fr;
        gap: 32px;
    }
    .footer-bottom {
        flex-direction: column;
        gap: 16px;
        text-align: center;
    }
}

@media (max-width: 480px) {
    .footer-links {
        grid-template-columns: 1fr;
    }
}