/* Color Variables */
:root {
  /* Color Palette - Light Mode */
  --primary: #2563EB;
  --primary-hover: #1D4ED8;
  --secondary: #4F46E5;
  --secondary-hover: #4338CA;
  --accent: #06B6D4;
  --success: #10B981;
  --warning: #F59E0B;
  --danger: #EF4444;
  --bg-app: #F8FAFC;
  --bg-surface: #FFFFFF;
  --border: #E5E7EB;
  --text-primary: #111827;
  --text-secondary: #4B5563;
  --text-inverse: #FFFFFF;
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.05), 0 2px 4px -1px rgba(0, 0, 0, 0.03);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.05), 0 4px 6px -2px rgba(0, 0, 0, 0.02);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.05), 0 10px 10px -5px rgba(0, 0, 0, 0.02);
  --glass-bg: rgba(255, 255, 255, 0.8);
  --glass-border: rgba(229, 231, 235, 0.5);
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --font-heading: 'Poppins', sans-serif;
  --font-mono: 'JetBrains Mono', monospace;
  --radius-sm: 0.375rem;
  --radius-md: 0.75rem;
  --radius-lg: 1.25rem;
  --radius-full: 9999rem;
  --transition-fast: 0.15s ease;
  --transition-normal: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

/* Dark Mode Overrides */
html.dark {
  --primary: #3B82F6;
  --primary-hover: #60A5FA;
  --secondary: #6366F1;
  --secondary-hover: #818CF8;
  --accent: #22D3EE;
  --success: #34D399;
  --warning: #FBBF24;
  --danger: #F87171;
  --bg-app: #0F172A;
  --bg-surface: #1E293B;
  --border: #334155;
  --text-primary: #F8FAFC;
  --text-secondary: #CBD5E1;
  --text-inverse: #0F172A;
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.5);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.3), 0 2px 4px -1px rgba(0, 0, 0, 0.2);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.3), 0 4px 6px -2px rgba(0, 0, 0, 0.2);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.4), 0 10px 10px -5px rgba(0, 0, 0, 0.3);
  --glass-bg: rgba(15, 23, 42, 0.8);
  --glass-border: rgba(51, 65, 85, 0.5);
}

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

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

body {
  font-family: var(--font-sans);
  background-color: var(--bg-app);
  color: var(--text-primary);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
  transition: background-color var(--transition-normal), color var(--transition-normal);
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: 700;
  line-height: 1.25;
  color: var(--text-primary);
}

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

button, input, select, textarea {
  font-family: inherit;
  font-size: inherit;
  color: inherit;
  background: none;
  border: none;
  outline: none;
}

ul {
  list-style: none;
}

/* Container */
.container {
  width: 100%;
  max-width: 1280px;
  margin-left: auto;
  margin-right: auto;
  padding-left: 1.5rem;
  padding-right: 1.5rem;
}

/* Header & Sticky Nav */
header.sticky-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 10000;
  background: var(--glass-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--glass-border);
  transition: background var(--transition-normal), border-color var(--transition-normal), transform var(--transition-normal);
}

header.sticky-header.nav-up {
  transform: translateY(-100%);
}

.nav-container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 4.5rem;
}

/* Logo */
.logo {
  display: flex;
  align-items: center;
  gap: 0.625rem;
  font-weight: 800;
  font-size: 1.5rem;
  color: var(--text-primary);
  font-family: var(--font-heading);
  user-select: none;
}

.logo svg {
  width: 2.25rem;
  height: 2.25rem;
}

/* Nav Menu */
.nav-menu {
  display: flex;
  align-items: center;
  gap: 2rem;
}

.nav-link {
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--text-secondary);
  display: flex;
  align-items: center;
  gap: 0.375rem;
  padding: 0.5rem 0.75rem;
  border-radius: var(--radius-sm);
}

.nav-link:hover, .nav-link.active, .dropdown.active-parent .dropdown-toggle {
  color: var(--primary);
}

/* Dropdown Menu */
.dropdown {
  position: relative;
}

.dropdown-toggle {
  cursor: pointer;
}

.dropdown-toggle svg {
  width: 0.875rem;
  height: 0.875rem;
  transition: transform var(--transition-fast);
}

.dropdown:hover .dropdown-toggle svg {
  transform: rotate(180deg);
}

.dropdown-menu {
  position: absolute;
  top: 100%;
  left: 50%;
  transform: translateX(-50%) translateY(10px);
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-xl);
  padding: 1.25rem;
  min-width: 580px;
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 0.5rem 1rem;
  opacity: 0;
  visibility: hidden;
  transition: opacity var(--transition-fast), transform var(--transition-fast), visibility var(--transition-fast);
  z-index: 110;
}

.dropdown:hover .dropdown-menu,
.dropdown:focus-within .dropdown-menu {
  opacity: 1;
  visibility: visible;
  transform: translateX(-50%) translateY(0);
}

.dropdown-item {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.625rem 0.75rem;
  border-radius: var(--radius-sm);
  color: var(--text-secondary);
  font-weight: 500;
  font-size: 0.9rem;
}

.dropdown-item:hover {
  background-color: var(--bg-app);
  color: var(--primary);
}

.dropdown-item-title {
  display: block;
  font-weight: 600;
  color: var(--text-primary);
}

.dropdown-item-desc {
  display: block;
  font-size: 0.75rem;
  color: var(--text-secondary);
}

/* CTA Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  font-weight: 600;
  font-size: 0.95rem;
  padding: 0.75rem 1.5rem;
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: background var(--transition-fast), color var(--transition-fast), transform var(--transition-fast), box-shadow var(--transition-fast);
}

.btn:active {
  transform: scale(0.98);
}

.btn-primary {
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  color: #FFFFFF;
  box-shadow: 0 4px 14px 0 rgba(37, 99, 235, 0.2);
}

.btn-primary:hover {
  background: linear-gradient(135deg, var(--primary-hover), var(--secondary-hover));
  box-shadow: 0 6px 20px 0 rgba(37, 99, 235, 0.3);
}

.btn-secondary {
  background-color: var(--bg-surface);
  color: var(--text-primary);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
}

.btn-secondary:hover {
  background-color: var(--bg-app);
  border-color: var(--text-secondary);
}

.btn-ghost {
  color: var(--text-secondary);
}

.btn-ghost:hover {
  color: var(--text-primary);
  background-color: var(--bg-app);
}

.btn-icon {
  width: 2.5rem;
  height: 2.5rem;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--border);
  background-color: var(--bg-surface);
  cursor: pointer;
  color: var(--text-primary);
  transition: background-color var(--transition-fast), border-color var(--transition-fast);
}

.btn-icon:hover {
  background-color: var(--bg-app);
  border-color: var(--text-secondary);
}

/* Nav Actions */
.nav-actions {
  display: flex;
  align-items: center;
  gap: 1rem;
}

/* Mobile Hamburger Menu */
.hamburger {
  display: none;
  flex-direction: column;
  justify-content: space-between;
  width: 1.5rem;
  height: 1.125rem;
  background: transparent;
  cursor: pointer;
  z-index: 120;
}

.hamburger span {
  width: 100%;
  height: 2px;
  background-color: var(--text-primary);
  border-radius: 2px;
  transition: all var(--transition-normal);
  transform-origin: left center;
}

/* Hamburger Active States */
.hamburger.active span:nth-child(1) {
  transform: rotate(45deg);
}

.hamburger.active span:nth-child(2) {
  width: 0%;
  opacity: 0;
}

.hamburger.active span:nth-child(3) {
  transform: rotate(-45deg);
}

/* Spacer for Sticky Nav */
.header-spacer {
  height: 4.5rem;
}

/* Footer Section */
footer {
  background-color: var(--bg-surface);
  border-top: 1px solid var(--border);
  padding: 5rem 0 2rem;
  margin-top: 5rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr repeat(3, 1fr);
  gap: 4rem;
  margin-bottom: 4rem;
}

.footer-brand {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.footer-desc {
  color: var(--text-secondary);
  font-size: 0.95rem;
  max-width: 320px;
}

.footer-title {
  font-size: 0.9rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-primary);
  margin-bottom: 1.25rem;
}

.footer-links {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

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

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

.footer-bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-top: 2rem;
  border-top: 1px solid var(--border);
  color: var(--text-secondary);
  font-size: 0.9rem;
}

.footer-socials {
  display: flex;
  gap: 1.25rem;
}

.footer-social-icon {
  color: var(--text-secondary);
  transition: color var(--transition-fast);
}

.footer-social-icon:hover {
  color: var(--primary);
}

.footer-social-icon svg {
  width: 1.25rem;
  height: 1.25rem;
}

/* Section Header Styles */
.section-header {
  text-align: center;
  max-width: 640px;
  margin: 0 auto 3.5rem;
}

.section-tag {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--secondary);
  background-color: rgba(79, 70, 229, 0.1);
  padding: 0.35rem 0.75rem;
  border-radius: var(--radius-full);
  margin-bottom: 1rem;
}

.section-title {
  font-size: 2.25rem;
  margin-bottom: 1rem;
}

.section-subtitle {
  font-size: 1.1rem;
  color: var(--text-secondary);
}

/* Breadcrumb Styling */
.breadcrumbs {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.85rem;
  color: var(--text-secondary);
  margin-top: 1.5rem;
  margin-bottom: 1.5rem;
}

.breadcrumbs a {
  display: flex;
  align-items: center;
  gap: 0.25rem;
}

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

.breadcrumbs svg {
  width: 0.875rem;
  height: 0.875rem;
}

.breadcrumbs .separator {
  color: var(--border);
}

.breadcrumbs span.current {
  color: var(--text-primary);
  font-weight: 500;
}

/* Visually Hidden for Accessibility */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* Focus States for Accessibility */
a:focus-visible, button:focus-visible, input:focus-visible, select:focus-visible, textarea:focus-visible {
  outline: 2px solid var(--primary);
  outline-offset: 2px;
}

/* Toast Message */
.toast {
  position: fixed;
  bottom: 2rem;
  left: 50%;
  transform: translateX(-50%) translateY(100px);
  background-color: var(--text-primary);
  color: var(--text-inverse);
  padding: 0.75rem 1.5rem;
  border-radius: var(--radius-full);
  font-weight: 600;
  font-size: 0.9rem;
  box-shadow: var(--shadow-xl);
  display: flex;
  align-items: center;
  gap: 0.5rem;
  z-index: 1000;
  transition: transform 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

.toast.show {
  transform: translateX(-50%) translateY(0);
}

.toast svg {
  width: 1.125rem;
  height: 1.125rem;
  color: var(--success);
}

/* Premium Apple-Inspired Theme Toggle Button */
.theme-toggle.btn-icon {
  width: 2.75rem;
  height: 2.75rem;
  border-radius: 50%;
  background-color: var(--bg-surface);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  transition: background-color var(--transition-normal), border-color var(--transition-normal), transform var(--transition-normal), box-shadow var(--transition-normal);
}

.theme-toggle.btn-icon:hover {
  transform: scale(1.08);
  box-shadow: var(--shadow-md);
  border-color: var(--primary);
  background-color: rgba(37, 99, 235, 0.03);
}

.theme-toggle.btn-icon:active {
  transform: scale(0.92);
}

.theme-toggle.btn-icon svg {
  width: 1.25rem;
  height: 1.25rem;
  transition: transform 0.5s cubic-bezier(0.34, 1.56, 0.64, 1), opacity var(--transition-normal);
}

/* Custom icon animations on toggles */
html.dark .theme-toggle.btn-icon .sun-icon {
  animation: rotateIn 0.5s cubic-bezier(0.34, 1.56, 0.64, 1) forwards;
  color: #FBBF24;
}

.theme-toggle.btn-icon .moon-icon {
  color: #6366F1;
  animation: rotateIn 0.5s cubic-bezier(0.34, 1.56, 0.64, 1) forwards;
}

@keyframes rotateIn {
  from {
    transform: rotate(-75deg) scale(0.85);
    opacity: 0;
  }
  to {
    transform: rotate(0) scale(1);
    opacity: 1;
  }
}

/* Responsive Grid Utilities */
.grid-responsive-2 {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2.5rem;
}
.grid-responsive-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2rem;
}
.grid-responsive-4 {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 2rem;
}
.grid-hero-responsive {
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: 4rem;
  align-items: center;
}

@media (max-width: 1024px) {
  .grid-responsive-4 {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  .grid-responsive-2,
  .grid-responsive-3,
  .grid-responsive-4,
  .grid-hero-responsive {
    grid-template-columns: 1fr;
    gap: 2rem;
  }
}

.mobile-menu-cta {
  display: none;
}