:root {
  /* Primary -- Ocean Teal */
  --ocean-50: #f0fdfa;
  --ocean-100: #ccfbf1;
  --ocean-200: #99f6e4;
  --ocean-300: #5eead4;
  --ocean-400: #2dd4bf;
  --ocean-500: #14b8a6;
  --ocean-600: #0d9488;
  --ocean-700: #0f766e;
  --ocean-800: #115e59;
  --ocean-900: #134e4a;
  --ocean-950: #042f2e;

  /* Accent -- Coral/Amber (CTA) */
  --coral-400: #FB923C;
  --coral-500: #F97316;
  --coral-600: #EA580C;
  --coral-700: #C2410C;

  /* Neutral -- Sand */
  --sand-50: #FBF8F3;
  --sand-100: #F5F0E8;
  --sand-200: #EBE3D5;
  --sand-300: #DDD0BC;

  /* Semantic */
  --success-bg: #ecfdf5;
  --success-text: #059669;
  --error-bg: #fef2f2;
  --error-text: #ef4444;
  --rating-star: #fbbf24;

  /* Spacing */
  --space-sm: 8px;
  --space-md: 16px;
  --space-lg: 24px;
  --space-xl: 32px;
  --space-2xl: 48px;
  --space-3xl: 64px;

  /* Border Radius */
  --radius-lg: 8px;
  --radius-xl: 12px;
  --radius-2xl: 16px;

  /* Shadows */
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.07);
  --shadow-lg: 0 10px 25px rgba(0, 0, 0, 0.1);
  --shadow-xl: 0 20px 40px rgba(0, 0, 0, 0.15);

  /* Transitions */
  --transition-fast: 200ms ease-out;
  --transition-normal: 300ms ease-out;
  --transition-slow: 500ms ease-out;
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: 'Inter', system-ui, -apple-system, sans-serif;
  background-color: var(--sand-50);
  color: #1e293b;
  /* slate-800 */
  line-height: 1.5;
  overflow-x: hidden;
}

h1,
h2,
h3 {
  color: #0f172a;
  /* slate-900 */
  font-weight: 700;
  line-height: 1.2;
}

h1 {
  font-size: clamp(36px, 8vw, 48px);
  letter-spacing: -0.02em;
}

h2 {
  font-size: clamp(24px, 5vw, 30px);
  margin-bottom: var(--space-md);
}

h3 {
  font-size: 20px;
  margin-bottom: var(--space-sm);
}

p {
  margin-bottom: var(--space-md);
}

a {
  color: var(--ocean-600);
  text-decoration: none;
  transition: var(--transition-fast);
}

a:hover {
  color: var(--ocean-700);
}

ul {
  list-style: none;
}

.container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 var(--space-lg);
}

/* --- Layout Components --- */

/* Progress Bar */
#progress-bar {
  position: fixed;
  top: 0;
  left: 0;
  width: 0%;
  height: 4px;
  background: linear-gradient(to right, var(--ocean-400), var(--ocean-600));
  z-index: 1000;
  transition: width 150ms ease-out;
}

/* Top Header (Static) */
.top-header {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  padding: 24px var(--space-lg);
  display: flex;
  justify-content: space-between;
  align-items: center;
  z-index: 50;
  background: transparent;
}

/* Floating Tab Nav (Sticky) */
#sticky-nav {
  position: fixed;
  top: 16px;
  left: 50%;
  transform: translateX(-50%) translateY(-150%);
  width: max-content;
  max-width: 90%;
  background: rgba(255, 255, 255, 0.9);
  backdrop-filter: blur(16px);
  padding: 8px;
  border-radius: 9999px;
  display: flex;
  justify-content: center;
  align-items: center;
  box-shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.1), 0 8px 10px -6px rgba(0, 0, 0, 0.1);
  z-index: 999;
  transition: transform 400ms cubic-bezier(0.16, 1, 0.3, 1);
  border: 1px solid rgba(255, 255, 255, 0.5);
}

#sticky-nav.visible {
  transform: translateX(-50%) translateY(0);
}

.nav-links {
  display: flex;
  gap: 4px;
}

.nav-link {
  font-size: 14px;
  font-weight: 500;
  color: #475569;
  /* slate-600 */
  padding: 8px 16px;
  border-radius: 9999px;
  transition: all 200ms ease;
}

.nav-link:hover {
  background: #f1f5f9;
  /* slate-100 */
  color: #0f172a;
  /* slate-900 */
}

.nav-link.active {
  background: white;
  color: var(--ocean-700);
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
  font-weight: 600;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-xl);
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition-fast);
  border: none;
  text-align: center;
}

.btn-primary {
  background: var(--coral-500);
  color: white;
  padding: 16px 32px;
  font-size: 18px;
}

.btn-primary:hover {
  background: var(--coral-600);
  box-shadow: 0 10px 20px -5px rgba(249, 115, 22, 0.3);
  transform: translateY(-1px);
}

.btn-secondary {
  background: rgba(255, 255, 255, 0.15);
  color: white;
  backdrop-filter: blur(8px);
  border: 1px solid rgba(255, 255, 255, 0.2);
  padding: 14px 24px;
}

.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.25);
}

.btn-sm {
  padding: 8px 16px;
  font-size: 14px;
  border-radius: 9999px;
}

/* Badges & Pills */
.badge-solid {
  background-color: rgba(13, 148, 136, 0.9);
  /* ocean-600/90 */
  color: white;
  font-size: 12px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  padding: 4px 12px;
  border-radius: 9999px;
}

.badge-glass {
  background-color: rgba(255, 255, 255, 0.2);
  backdrop-filter: blur(4px);
  color: white;
  font-size: 12px;
  font-weight: 500;
  padding: 4px 12px;
  border-radius: 9999px;
}

/* Icon Containers */
.icon-box {
  width: 48px;
  height: 48px;
  background-color: var(--ocean-50);
  color: var(--ocean-600);
  border-radius: 12px;
  /* Soft square like React */
  display: flex;
  align-items: center;
  justify-content: center;
}

/* Animations */
.fade-in-up {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity var(--transition-slow), transform var(--transition-slow);
}

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

/* Mobile Utils */
@media (max-width: 639px) {
  .container {
    padding: 0 var(--space-md);
  }

  .nav-links {
    display: none;
  }
}