:root {
  /* Brand Colors */
  --primary: #0056b3;
  --primary-hover: #004494;
  --secondary: #333333;
  --accent: #eef2f6;

  /* Background & Text Colors - Light Mode */
  --bg-color: #ffffff;
  --text-main: #333333;
  --text-muted: #666666;
  --bg-card: #ffffff;
  --border-color: #dddddd;

  /* Navbar */
  --nav-bg: rgba(255, 255, 255, 0.95);
  --nav-text: #333333;

  /* Typography */
  --font-main: 'Inter', sans-serif;
  --spacing-base: 1rem;
  --border-radius: 8px;
  --transition: all 0.3s ease;
  --shadow: 0 4px 6px rgba(0, 0, 0, 0.05);
  --shadow-hover: 0 10px 15px rgba(0, 0, 0, 0.1);
}

/* Dark Mode Constants */
[data-theme="dark"] {
  --primary: #4da3ff;
  --primary-hover: #80bfff;
  --secondary: #f4f4f4;
  --accent: #2a2d33;

  --bg-color: #121212;
  --text-main: #e0e0e0;
  --text-muted: #aaaaaa;
  --bg-card: #1e1e1e;
  --border-color: #333333;

  --nav-bg: rgba(18, 18, 18, 0.95);
  --nav-text: #e0e0e0;
  --shadow: 0 4px 6px rgba(0, 0, 0, 0.3);
  --shadow-hover: 0 10px 15px rgba(0, 0, 0, 0.5);
}

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

body {
  font-family: var(--font-main);
  background-color: var(--bg-color);
  color: var(--text-main);
  line-height: 1.6;
  overflow-x: hidden;
  transition: background-color var(--transition), color var(--transition);
}

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

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

h1, h2, h3, h4 {
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 0.5em;
  line-height: 1.2;
}

h1 { font-size: 2.5rem; }
h2 { font-size: 2rem; }
h3 { font-size: 1.5rem; }

p { margin-bottom: 1rem; }
img { max-width: 100%; height: auto; }

/* Container */
.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

/* Header & Navigation */
header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  background: var(--nav-bg);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  z-index: 1000;
  box-shadow: 0 2px 4px rgba(0,0,0,0.05);
  transition: var(--transition);
}

.nav-container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 80px;
}

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

.logo img {
  height: 60px;
}

.logo-dark {
  display: none;
}

[data-theme="dark"] .logo-light {
  display: none;
}

[data-theme="dark"] .logo-dark {
  display: block;
}

.nav-links {
  display: flex;
  list-style: none;
  align-items: center;
  gap: 2rem;
}

.nav-links a {
  color: var(--nav-text);
  font-weight: 500;
  font-size: 1rem;
}

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

/* Burger Menu */
.burger {
  display: none;
  cursor: pointer;
}

.burger div {
  width: 25px;
  height: 3px;
  background-color: var(--nav-text);
  margin: 5px;
  transition: var(--transition);
}

/* Theme Toggle */
.theme-toggle {
  background: none;
  border: none;
  color: var(--nav-text);
  font-size: 1.2rem;
  cursor: pointer;
  display: flex;
  align-items: center;
  padding: 0.5rem;
}

/* Buttons */
.btn {
  display: inline-block;
  padding: 0.8rem 1.8rem;
  border-radius: var(--border-radius);
  font-weight: 600;
  text-align: center;
  cursor: pointer;
  border: none;
  transition: var(--transition);
}

.btn-primary {
  background-color: var(--primary);
  color: #fff !important;
}

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

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

.btn-secondary:hover {
  background-color: var(--primary);
  color: #fff !important;
  transform: translateY(-2px);
}

/* Sections */
.section {
  padding: 5rem 0;
}

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

.section-title {
  text-align: center;
  margin-bottom: 3rem;
}

/* Hero Section */
.hero {
  padding-top: 150px;
  padding-bottom: 6rem;
  text-align: center;
  background: linear-gradient(135deg, var(--bg-color) 0%, var(--accent) 100%);
}

.hero h1 {
  font-size: 3.5rem;
  margin-bottom: 1.5rem;
  color: var(--text-main);
}

.hero p.lead {
  font-size: 1.25rem;
  color: var(--text-muted);
  max-width: 800px;
  margin: 0 auto 2.5rem;
}

.hero-actions {
  display: flex;
  gap: 1rem;
  justify-content: center;
}

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

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

.card:hover {
  transform: translateY(-10px);
  box-shadow: var(--shadow-hover);
  border-color: var(--primary);
}

.card-icon {
  font-size: 3rem;
  color: var(--primary);
  margin-bottom: 1.5rem;
}

.card-title {
  font-size: 1.25rem;
  margin-bottom: 1rem;
}

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

/* Footer */
footer {
  background-color: #1a1a1a;
  color: #cccccc;
  padding: 4rem 0 2rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 2rem;
  margin-bottom: 3rem;
}

.footer-col h4 {
  color: #ffffff;
  margin-bottom: 1.5rem;
}

.footer-col ul {
  list-style: none;
}

.footer-col ul li {
  margin-bottom: 0.5rem;
}

.footer-col a {
  color: #aaaaaa;
}

.footer-col a:hover {
  color: var(--primary);
}

.footer-bottom {
  text-align: center;
  border-top: 1px solid #333333;
  padding-top: 2rem;
  font-size: 0.9rem;
}

/* Form Styles */
.form-group {
  margin-bottom: 1.5rem;
}

.form-label {
  display: block;
  margin-bottom: 0.5rem;
  font-weight: 500;
}

.form-control {
  width: 100%;
  padding: 0.8rem;
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius);
  background-color: var(--bg-color);
  color: var(--text-main);
  font-family: var(--font-main);
  transition: var(--transition);
}

.form-control:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(0, 86, 179, 0.1);
}

/* Contact Layout */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 4rem;
}

.contact-info {
  display: flex;
  flex-direction: column;
  gap: 2rem;
}

.info-item {
  display: flex;
  align-items: flex-start;
  gap: 1rem;
}

.info-icon {
  font-size: 2rem;
  color: var(--primary);
}

/* Animations */
.fade-in {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}

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

/* Responsive Design */
@media screen and (max-width: 768px) {
  .hero h1 { font-size: 2.5rem; }
  .contact-grid { grid-template-columns: 1fr; gap: 2rem; }
  
  .nav-links {
    position: fixed;
    right: -100%;
    top: 80px;
    height: calc(100vh - 80px);
    background-color: var(--nav-bg);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: flex-start;
    padding-top: 2rem;
    width: 100%;
    transition: var(--transition);
    box-shadow: 0 10px 15px rgba(0,0,0,0.1);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
  }

  .nav-links.active {
    right: 0;
  }

  .burger {
    display: block;
  }

  .burger.toggle .line1 {
    transform: rotate(-45deg) translate(-5px, 6px);
  }

  .burger.toggle .line2 {
    opacity: 0;
  }

  .burger.toggle .line3 {
    transform: rotate(45deg) translate(-5px, -6px);
  }
}