:root {
  /* Premium Dark Blue / Industrial Color Palette */
  --primary-color: #0b2545;
  --secondary-color: #13315c;
  --accent-color: #1a659e;
  --highlight-color: #ff6b35; /* Orange accent for industrial pop */
  
  --bg-color: #ffffff;
  --bg-secondary: #f8f9fa;
  --text-main: #2b2d42;
  --text-muted: #6c757d;
  --text-light: #f8f9fa;
  --border: #e2e8f0;
  --section-dark-bg: var(--primary-color);
  
  --nav-height: 80px;
  
  --font-sans: 'Inter', system-ui, -apple-system, sans-serif;
  --font-heading: 'Outfit', 'Inter', system-ui, sans-serif;

  --shadow-sm: 0 2px 4px rgba(0,0,0,0.05);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.08);
  --shadow-lg: 0 12px 24px rgba(0,0,0,0.12);
  --shadow-hover: 0 20px 40px rgba(0,0,0,0.15);
  
  --transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
}

:root[data-theme="dark"] {
  --primary-color: #f8fafc;
  --secondary-color: #1e293b;
  --accent-color: #00e5ff; /* Vibrant Neon Cyan */
  --highlight-color: #ff3d00; /* Blazing Neon Orange */
  --bg-color: #0b1120;
  --bg-secondary: #020617;
  --section-dark-bg: #040d21;
  --text-main: #f1f5f9;
  --text-muted: #cbd5e1;
  --border: rgba(0, 229, 255, 0.15); /* Subtle cyan tint on borders */
  
  /* Stronger neon cyan glow on hover */
  --shadow-sm: 0 2px 4px rgba(0,0,0,0.5);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.8);
  --shadow-lg: 0 12px 24px rgba(0,0,0,0.9);
  --shadow-hover: 0 0 25px rgba(0, 229, 255, 0.4);
}

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

html {
  scroll-behavior: smooth;
  font-family: var(--font-sans);
  color: var(--text-main);
  background-color: var(--bg-color);
  line-height: 1.6;
  overflow-x: hidden;
}

body {
  overflow-x: hidden;
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  line-height: 1.2;
  font-weight: 700;
  color: var(--primary-color);
}

input, textarea, select {
  color: var(--text-main);
  font-family: inherit;
}

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

ul {
  list-style: none;
}

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

/* Layout Containers */
.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

.section {
  padding: 100px 0;
  scroll-margin-top: calc(var(--nav-height) + 20px);
}

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

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

.section-dark h2 {
  color: var(--text-light);
}

/* Typography Utility */
.text-center { text-align: center; }
.section-title {
  font-size: 2.5rem;
  margin-bottom: 1rem;
  position: relative;
  display: inline-block;
}
.section-title::after {
  content: '';
  position: absolute;
  bottom: -10px;
  left: 50%;
  transform: translateX(-50%);
  width: 60px;
  height: 4px;
  background: var(--highlight-color);
  border-radius: 2px;
}
.section-subtitle {
  color: var(--text-muted);
  font-size: 1.125rem;
  max-width: 600px;
  margin: 0 auto 3rem;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px 28px;
  font-size: 1rem;
  font-weight: 600;
  border-radius: 6px;
  cursor: pointer;
  border: none;
  transition: var(--transition);
}

.btn-primary {
  background-color: var(--highlight-color);
  color: #fff;
  box-shadow: var(--shadow-md);
}

.btn-primary:hover {
  background-color: #e55a2b;
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

.btn-outline {
  background-color: transparent;
  color: var(--primary-color);
  border: 2px solid var(--primary-color);
}

.btn-outline:hover {
  background-color: var(--primary-color);
  color: var(--text-light);
}

/* Header & Nav */
.header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: var(--nav-height);
  background: var(--bg-color);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  z-index: 1000;
  box-shadow: var(--shadow-sm);
  transition: var(--transition);
}

.header.scrolled {
  height: 70px;
  box-shadow: var(--shadow-md);
}

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

.logo {
  font-family: var(--font-heading);
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--primary-color);
  letter-spacing: -0.5px;
}

.logo span {
  color: var(--highlight-color);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 2rem;
}

.nav-link {
  font-weight: 500;
  color: var(--text-main);
  position: relative;
}

.nav-link::after {
  content: '';
  position: absolute;
  width: 0;
  height: 2px;
  bottom: -4px;
  left: 0;
  background-color: var(--highlight-color);
  transition: width 0.3s ease;
}

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

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

/* Mobile Menu Button */
.mobile-menu-btn {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 5px;
  z-index: 1001;
}

.hamburger {
  display: block;
  width: 24px;
  height: 2px;
  background-color: var(--primary-color);
  position: relative;
  transition: var(--transition);
}

.hamburger::before, .hamburger::after {
  content: '';
  position: absolute;
  width: 100%;
  height: 2px;
  background-color: var(--primary-color);
  left: 0;
  transition: var(--transition);
}

.hamburger::before { top: -8px; }
.hamburger::after { bottom: -8px; }

/* Mobile Menu Active State */
.mobile-menu-btn.active .hamburger {
  background-color: transparent;
}
.mobile-menu-btn.active .hamburger::before {
  top: 0;
  transform: rotate(45deg);
}
.mobile-menu-btn.active .hamburger::after {
  bottom: 0;
  transform: rotate(-45deg);
}

/* Theme Toggle */
.theme-toggle {
  background: none;
  border: none;
  color: var(--primary-color);
  cursor: pointer;
  padding: 8px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: var(--transition);
}

.theme-toggle:hover {
  background: var(--bg-secondary);
}

.theme-toggle svg {
  width: 20px;
  height: 20px;
  stroke: currentColor;
  fill: none;
}

[data-theme="dark"] .moon-icon {
  display: none;
}
[data-theme="dark"] .sun-icon {
  display: block;
}
[data-theme="light"] .moon-icon, :root:not([data-theme="dark"]) .moon-icon {
  display: block;
}
[data-theme="light"] .sun-icon, :root:not([data-theme="dark"]) .sun-icon {
  display: none;
}

/* Hero Section */
.hero {
  padding-top: calc(var(--nav-height) + 60px);
  padding-bottom: 100px;
  min-height: 90vh;
  display: flex;
  align-items: center;
  background: linear-gradient(135deg, var(--bg-secondary) 0%, var(--bg-color) 100%);
  position: relative;
}

.hero::before {
  content: '';
  position: absolute;
  top: 0;
  right: 0;
  width: 50%;
  height: 100%;
  background: url('https://images.unsplash.com/photo-1581091226825-a6a2a5aee158?q=80&w=2070&auto=format&fit=crop') center/cover no-repeat;
  opacity: 0.1;
  border-bottom-left-radius: 100px;
  z-index: 0;
}

.hero-content {
  position: relative;
  z-index: 1;
  max-width: 600px;
}

.hero h1 {
  font-size: 3.5rem;
  margin-bottom: 1.5rem;
  line-height: 1.1;
}

.hero p {
  font-size: 1.25rem;
  color: var(--text-muted);
  margin-bottom: 2rem;
}

.hero-buttons {
  display: flex;
  gap: 1rem;
}

/* Cards Grid */
.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
}

.card {
  background: var(--bg-color);
  border-radius: 12px;
  padding: 2.5rem 2rem;
  box-shadow: var(--shadow-sm);
  transition: var(--transition);
  border: 1px solid var(--border);
  position: relative;
  overflow: hidden;
  text-align: center;
}

.card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 4px;
  background: var(--accent-color);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.4s ease;
}

.card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-hover);
}

.card:hover::before {
  transform: scaleX(1);
}

.card-icon {
  width: 60px;
  height: 60px;
  background: rgba(26, 101, 158, 0.1);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 1.5rem auto;
  color: var(--accent-color);
}

.card h3 {
  font-size: 1.5rem;
  margin-bottom: 1rem;
}

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

/* Scroll Animations */
.fade-up {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.8s ease, transform 0.8s ease;
}

.fade-up.visible {
  opacity: 1;
  transform: translateY(0);
}

/* Mobile Responsive */
@media (max-width: 768px) {
  .mobile-menu-btn {
    display: block;
  }
  
  .nav-links {
    position: fixed;
    top: var(--nav-height);
    left: -100%;
    width: 100%;
    height: calc(100vh - var(--nav-height));
    background: var(--bg-color);
    flex-direction: column;
    align-items: center;
    padding-top: 2rem;
    transition: left 0.4s ease;
    box-shadow: var(--shadow-md);
  }
  
  .nav-links.active {
    left: 0;
  }
  
  .hero h1 {
    font-size: 2.5rem;
  }
  
  .hero::before {
    width: 100%;
    border-radius: 0;
  }
  
  .section {
    padding: 60px 0;
  }
}

/* Infinite Carousel */
.carousel-track {
  display: flex;
  width: max-content;
  animation: scroll 60s linear infinite;
  align-items: center;
  transition: opacity 0.3s ease;
}

.carousel-track:hover {
  opacity: 1;
}

.carousel-slide {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 3rem;
  padding-right: 3rem;
}

@keyframes scroll {
  0% { transform: translateX(0); }
  100% { transform: translateX(-50%); }
}

.carousel-wrapper:hover .carousel-track {
  animation-play-state: paused;
}

.carousel-slide img {
  margin: 0;
  transition: var(--transition);
}

:root[data-theme="dark"] .carousel-slide img {
  background: rgba(255, 255, 255, 0.85);
  padding: 8px 16px;
  border-radius: 8px;
}