/* ========================================
   JD Mollineda Tech Hub - Main Stylesheet
   ======================================== */

/* ========================================
   1. CSS CUSTOM PROPERTIES (Variables)
   ======================================== */
:root {
  /* Colors */
  --color-primary: #0f3460;
  --color-primary-dark: #0a2238;
  --color-primary-light: #1a4d7a;
  --color-accent: #e94560;
  --color-accent-light: #ff6b7a;
  --color-success: #10a981;
  --color-warning: #f59e0b;
  --color-error: #ef4444;
  
  --color-text-dark: #1f2937;
  --color-text-light: #6b7280;
  --color-text-lighter: #9ca3af;
  
  --color-bg-light: #ffffff;
  --color-bg-gray: #f9fafb;
  --color-bg-dark-gray: #f3f4f6;
  --color-border: #e5e7eb;
  --color-border-dark: #d1d5db;
  
  /* Typography */
  --font-primary: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Helvetica Neue', sans-serif;
  --font-mono: 'Courier New', monospace;
  
  --font-size-xs: 0.75rem;
  --font-size-sm: 0.875rem;
  --font-size-base: 1rem;
  --font-size-lg: 1.125rem;
  --font-size-xl: 1.25rem;
  --font-size-2xl: 1.5rem;
  --font-size-3xl: 1.875rem;
  --font-size-4xl: 2.25rem;
  --font-size-5xl: 3rem;
  
  --font-weight-light: 300;
  --font-weight-normal: 400;
  --font-weight-medium: 500;
  --font-weight-semibold: 600;
  --font-weight-bold: 700;
  
  /* Spacing */
  --spacing-xs: 0.25rem;
  --spacing-sm: 0.5rem;
  --spacing-md: 1rem;
  --spacing-lg: 1.5rem;
  --spacing-xl: 2rem;
  --spacing-2xl: 3rem;
  --spacing-3xl: 4rem;
  --spacing-4xl: 6rem;
  
  /* Border Radius */
  --radius-sm: 0.25rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-2xl: 1.5rem;
  
  /* Shadows */
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
  
  /* Transitions */
  --transition-fast: 150ms ease-in-out;
  --transition-base: 300ms ease-in-out;
  --transition-slow: 500ms ease-in-out;
  
  /* Z-index */
  --z-dropdown: 1000;
  --z-modal: 1050;
  --z-tooltip: 1100;
  --z-nav: 999;
}

/* ========================================
   2. RESET & BASE STYLES
   ======================================== */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

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

body {
  font-family: var(--font-primary);
  color: var(--color-text-dark);
  background-color: var(--color-bg-light);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  font-weight: var(--font-weight-bold);
  line-height: 1.3;
  margin-bottom: var(--spacing-md);
}

h1 {
  font-size: var(--font-size-5xl);
}

h2 {
  font-size: var(--font-size-4xl);
}

h3 {
  font-size: var(--font-size-3xl);
}

h4 {
  font-size: var(--font-size-2xl);
}

h5 {
  font-size: var(--font-size-xl);
}

h6 {
  font-size: var(--font-size-lg);
}

p {
  margin-bottom: var(--spacing-md);
  color: var(--color-text-light);
}

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

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

a:focus {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
}

button, .btn {
  font-family: var(--font-primary);
  cursor: pointer;
  transition: all var(--transition-base);
}

input, textarea, select {
  font-family: var(--font-primary);
  font-size: var(--font-size-base);
}

/* ========================================
   3. LAYOUT COMPONENTS
   ======================================== */

/* Container */
.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-md);
}

.container-sm {
  max-width: 800px;
}

.container-lg {
  max-width: 1400px;
}

/* Grid System */
.grid {
  display: grid;
  gap: var(--spacing-lg);
}

.grid-cols-1 {
  grid-template-columns: 1fr;
}

.grid-cols-2 {
  grid-template-columns: repeat(2, 1fr);
}

.grid-cols-3 {
  grid-template-columns: repeat(3, 1fr);
}

.grid-cols-4 {
  grid-template-columns: repeat(4, 1fr);
}

/* Flexbox Utilities */
.flex {
  display: flex;
}

.flex-col {
  flex-direction: column;
}

.flex-center {
  justify-content: center;
  align-items: center;
}

.flex-between {
  justify-content: space-between;
  align-items: center;
}

.flex-wrap {
  flex-wrap: wrap;
}

.gap-sm { gap: var(--spacing-sm); }
.gap-md { gap: var(--spacing-md); }
.gap-lg { gap: var(--spacing-lg); }
.gap-xl { gap: var(--spacing-xl); }

/* ========================================
   4. HEADER & NAVIGATION
   ======================================== */

.site-header {
  --header-height: 76px;
  position: sticky;
  top: 0;
  z-index: var(--z-nav);
  background: rgba(10, 20, 40, 0.92);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
  box-shadow: 0 4px 16px rgba(10, 20, 40, 0.32);
}

.header-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  min-height: var(--header-height);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 var(--spacing-md);
  gap: var(--spacing-md);
}

.brand-logo {
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-bold);
  color: #ffffff;
  text-decoration: none;
  letter-spacing: 0.02em;
  transition: color var(--transition-base);
}

.brand-logo:hover {
  color: var(--color-accent);
}

.primary-actions {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
}

.primary-link {
  font-size: var(--font-size-sm);
  color: rgba(255, 255, 255, 0.92);
  text-decoration: none;
  font-weight: var(--font-weight-medium);
  padding: 0.4rem 0.75rem;
  border-radius: var(--radius-sm);
  transition: background-color var(--transition-base), color var(--transition-base), transform var(--transition-base);
}

.primary-link:hover,
.primary-link:focus-visible {
  color: var(--color-accent);
  background: rgba(8, 160, 190, 0.15);
  transform: translateY(-1px);
}

.primary-link.active {
  color: var(--color-accent);
  border-bottom: 2px solid var(--color-accent);
}

.menu-btn {
  background: rgba(25, 35, 58, 0.9);
  border: 1px solid rgba(255, 255, 255, 0.18);
  color: white;
  border-radius: var(--radius-md);
  min-width: 100px;
  line-height: 1;
  padding: 0.55rem 0.85rem;
  cursor: pointer;
  font-weight: 700;
  letter-spacing: 0.03em;
  transition: all var(--transition-base);
}

.menu-btn:hover,
.menu-btn:focus-visible {
  background: rgba(6, 20, 40, 0.95);
  box-shadow: 0 8px 28px rgba(0, 0, 0, 0.25);
}

.menu-btn[aria-expanded="true"] {
  background: rgba(0, 140, 210, 0.9);
}

.site-sitemap {
  position: fixed;
  inset: 0;
  visibility: hidden;
  opacity: 0;
  transition: opacity var(--transition-base), visibility var(--transition-fast);
  display: flex;
  align-items: flex-start;
  justify-content: flex-end;
  z-index: calc(var(--z-nav) + 20);
}

.site-sitemap.open {
  visibility: visible;
  opacity: 1;
}

.sitemap-backdrop {
  position: absolute;
  inset: 0;
  background: rgba(0, 0, 0, 0.48);
  backdrop-filter: blur(4px);
}

.sitemap-panel {
  position: relative;
  width: min(92vw, 1000px);
  max-height: min(95vh, 760px);
  margin: 1.5rem;
  background: rgba(14, 24, 48, 0.92);
  backdrop-filter: blur(12px);
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: var(--radius-xl);
  padding: var(--spacing-lg);
  overflow: auto;
  transform: translateY(-18px);
  transition: transform var(--transition-base);
}

.site-sitemap.open .sitemap-panel {
  transform: translateY(0);
}

.panel-close {
  position: absolute;
  top: 1rem;
  right: 1rem;
  background: none;
  border: none;
  color: #ffffff;
  font-size: 1.3rem;
  cursor: pointer;
  padding: 0.25rem;
}

.sitemap-title {
  margin-bottom: var(--spacing-lg);
  color: white;
  font-size: var(--font-size-xl);
}

.sitemap-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(220px, 1fr));
  gap: var(--spacing-lg);
}

.sitemap-group {
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: var(--radius-lg);
  padding: var(--spacing-md);
  background: rgba(8, 16, 32, 0.8);
}

.sitemap-group h3 {
  margin-bottom: var(--spacing-xs);
  font-size: var(--font-size-lg);
  color: #eff5ff;
  letter-spacing: 0.01em;
}

.sitemap-group ul {
  list-style: none;
  margin: 0;
  padding: 0;
}

.sitemap-group li {
  margin: 0.4rem 0;
}

.sitemap-group a {
  color: rgba(230, 240, 255, 0.95);
  text-decoration: none;
  font-size: var(--font-size-sm);
  display: inline-block;
  transition: color var(--transition-base), transform var(--transition-base);
}

.sitemap-group a:hover,
.sitemap-group a:focus-visible {
  color: var(--color-accent);
  transform: translateX(2px);
}

/* Mobile / Tablet Drawer */
.mobile-drawer {
  position: fixed;
  inset: 0;
  transform: translateX(-110%);
  visibility: hidden;
  opacity: 0;
  transition: transform var(--transition-fast), visibility var(--transition-fast), opacity var(--transition-fast);
  z-index: calc(var(--z-nav) + 30);
  display: flex;
  justify-content: flex-start;
}

.mobile-drawer.open {
  visibility: visible;
  opacity: 1;
  transform: translateX(0);
}

.drawer-content {
  width: min(320px, 84vw);
  max-height: 100vh;
  overflow: auto;
  background: rgba(12, 24, 44, 0.94);
  border-right: 1px solid rgba(255, 255, 255, 0.14);
  padding: var(--spacing-lg);
  box-shadow: 4px 0 26px rgba(0, 0, 0, 0.3);
}

.drawer-close {
  background: none;
  border: none;
  color: #fff;
  font-size: 1.4rem;
  cursor: pointer;
  margin-bottom: var(--spacing-lg);
}

.drawer-links,
.drawer-links details summary {
  font-size: var(--font-size-base);
  line-height: 1.45;
}

.drawer-links a {
  display: block;
  padding: 0.5rem 0;
  color: rgba(237, 243, 255, 0.95);
  text-decoration: none;
  transition: color var(--transition-base), padding-left var(--transition-base);
}

.drawer-links a:hover,
.drawer-links a:focus-visible {
  color: var(--color-accent);
  padding-left: 0.4rem;
}

.drawer-links details summary {
  list-style: none;
  cursor: pointer;
  margin: var(--spacing-sm) 0;
  color: #e8f3ff;
  padding: 0.5rem 0;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.drawer-links details[open] summary {
  color: var(--color-accent);
}

.drawer-links details ul {
  margin-top: var(--spacing-xs);
  margin-left: var(--spacing-md);
}

.drawer-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.45);
  visibility: hidden;
  opacity: 0;
  transition: opacity var(--transition-fast), visibility var(--transition-fast);
  z-index: calc(var(--z-nav) + 25);
}

.drawer-overlay.open {
  visibility: visible;
  opacity: 1;
}

@media (max-width: 942px) {
  .primary-actions {
    display: none;
  }

  .menu-btn {
    min-width: auto;
    width: 45px;
    height: 45px;
    border-radius: 999px;
    font-weight: 600;
  }

  .site-sitemap {
    display: none;
  }

  .mobile-drawer {
    display: flex;
  }
}

@media (min-width: 943px) {
  .mobile-drawer,
  .drawer-overlay {
    display: none;
  }
}

/* ========================================
   5. FOOTER
   ======================================== */

footer {
  background-color: var(--color-primary);
  color: white;
  padding: var(--spacing-3xl) 0 var(--spacing-lg);
  margin-top: var(--spacing-4xl);
}

.footer-content {
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
}

.footer-section h4 {
  color: white;
  margin-bottom: var(--spacing-md);
}

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

.footer-section ul li {
  margin-bottom: var(--spacing-sm);
}

.footer-section a {
  color: rgba(255, 255, 255, 0.8);
  font-size: var(--font-size-sm);
  transition: color var(--transition-base);
}

.footer-section a:hover {
  color: var(--color-accent);
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding-top: var(--spacing-lg);
  text-align: center;
  color: rgba(255, 255, 255, 0.7);
  font-size: var(--font-size-sm);
}

.footer-legal {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: var(--spacing-lg);
}

.footer-legal a, .footer-bottom a {
  color: rgba(255, 255, 255, 0.8);
  font-size: var(--font-size-sm);
  transition: color var(--transition-base);
}

.footer-legal a:hover, .footer-bottom a:hover {
  color: var(--color-accent);
}

/* ========================================
   6. BUTTONS & CTAs
   ======================================== */

.btn {
  display: inline-block;
  padding: var(--spacing-md) var(--spacing-xl);
  border: 2px solid transparent;
  border-radius: var(--radius-lg);
  font-weight: var(--font-weight-semibold);
  font-size: var(--font-size-base);
  text-align: center;
  white-space: nowrap;
  transition: all var(--transition-base);
}

.btn-primary {
  background-color: var(--color-primary);
  color: white;
  border-color: var(--color-primary);
}

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

.btn-accent {
  background-color: var(--color-accent);
  color: white;
  border-color: var(--color-accent);
}

.btn-accent:hover {
  background-color: var(--color-accent-light);
  border-color: var(--color-accent-light);
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

.btn-secondary {
  background-color: var(--color-bg-light);
  color: var(--color-primary);
  border-color: var(--color-primary);
}

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

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

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

.btn-small {
  padding: var(--spacing-sm) var(--spacing-lg);
  font-size: var(--font-size-sm);
}

.btn-block {
  display: block;
  width: 100%;
}

/* ========================================
   7. CARDS & BOXES
   ======================================== */

.card {
  background-color: var(--color-bg-light);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  padding: var(--spacing-xl);
  transition: all var(--transition-base);
  word-wrap: break-word;
}

.card:hover {
  border-color: var(--color-accent);
  box-shadow: var(--shadow-lg);
  transform: translateY(-4px);
}

.card h3 {
  margin-top: 0;
}

.card-image {
  width: 100%;
  height: 200px;
  background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-light) 100%);
  border-radius: var(--radius-lg);
  margin-bottom: var(--spacing-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: var(--font-size-2xl);
}

.card-meta {
  display: flex;
  gap: var(--spacing-md);
  font-size: var(--font-size-sm);
  color: var(--color-text-lighter);
  margin-top: var(--spacing-md);
}

.card-category {
  display: inline-block;
  background-color: var(--color-bg-gray);
  color: var(--color-primary);
  padding: var(--spacing-xs) var(--spacing-md);
  border-radius: var(--radius-md);
  font-size: var(--font-size-xs);
  font-weight: var(--font-weight-semibold);
  text-transform: uppercase;
}

.card-cta {
  margin-top: var(--spacing-lg);
}

/* ========================================
   8. FORMS & INPUTS
   ======================================== */

.form-group {
  margin-bottom: var(--spacing-lg);
}

label {
  display: block;
  margin-bottom: var(--spacing-sm);
  font-weight: var(--font-weight-medium);
  color: var(--color-text-dark);
}

input[type="text"],
input[type="email"],
input[type="password"],
input[type="search"],
textarea,
select {
  width: 100%;
  padding: var(--spacing-md);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  font-size: var(--font-size-base);
  transition: all var(--transition-base);
}

input:focus,
textarea:focus,
select:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(15, 52, 96, 0.1);
}

textarea {
  resize: vertical;
  min-height: 120px;
}

.form-error {
  color: var(--color-error);
  font-size: var(--font-size-sm);
  margin-top: var(--spacing-sm);
}

.form-success {
  color: var(--color-success);
  font-size: var(--font-size-sm);
  margin-top: var(--spacing-sm);
}

/* ========================================
   9. SECTIONS & SPACING
   ======================================== */

section {
  padding: var(--spacing-3xl) 0;
}

section.hero {
  background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-light) 100%);
  color: white;
  padding: var(--spacing-4xl) 0;
  text-align: center;
}

section.hero h1 {
  font-size: var(--font-size-5xl);
  margin-bottom: var(--spacing-lg);
  color: white;
}

section.hero p {
  color: rgba(255, 255, 255, 0.9);
  font-size: var(--font-size-lg);
  margin-bottom: var(--spacing-lg);
}

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

/* ========================================
   10. SECTION TITLES & HEADINGS
   ======================================== */

.section-title {
  text-align: center;
  margin-bottom: var(--spacing-2xl);
}

.section-title h2 {
  margin-bottom: var(--spacing-md);
}

.section-title p {
  max-width: 600px;
  margin: 0 auto;
  font-size: var(--font-size-lg);
  color: var(--color-text-light);
}

.section-divider {
  width: 60px;
  height: 4px;
  background-color: var(--color-accent);
  margin: var(--spacing-md) auto;
  border-radius: var(--radius-md);
}

/* ========================================
   11. BREADCRUMBS
   ======================================== */

.breadcrumbs {
  display: flex;
  gap: var(--spacing-sm);
  font-size: var(--font-size-sm);
  margin-bottom: var(--spacing-xl);
  flex-wrap: wrap;
}

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

.breadcrumbs a:hover {
  text-decoration: underline;
}

.breadcrumbs span {
  color: var(--color-text-lighter);
}

/* ========================================
   12. LISTS & TABLES
   ======================================== */

ul, ol {
  margin-bottom: var(--spacing-md);
  padding-left: var(--spacing-xl);
}

li {
  margin-bottom: var(--spacing-sm);
  color: var(--color-text-light);
}

table {
  width: 100%;
  border-collapse: collapse;
  margin-bottom: var(--spacing-lg);
}

th, td {
  padding: var(--spacing-md);
  text-align: left;
  border-bottom: 1px solid var(--color-border);
}

th {
  background-color: var(--color-bg-gray);
  font-weight: var(--font-weight-bold);
}

tr:hover {
  background-color: var(--color-bg-gray);
}

/* ========================================
   13. BADGES & TAGS
   ======================================== */

.badge {
  display: inline-block;
  padding: var(--spacing-xs) var(--spacing-md);
  border-radius: var(--radius-full);
  font-size: var(--font-size-xs);
  font-weight: var(--font-weight-bold);
  text-transform: uppercase;
}

.badge-primary {
  background-color: var(--color-primary);
  color: white;
}

.badge-accent {
  background-color: var(--color-accent);
  color: white;
}

.badge-success {
  background-color: var(--color-success);
  color: white;
}

.tag {
  display: inline-block;
  padding: var(--spacing-xs) var(--spacing-lg);
  background-color: var(--color-bg-gray);
  color: var(--color-primary);
  border-radius: var(--radius-full);
  font-size: var(--font-size-xs);
  margin-right: var(--spacing-sm);
  margin-bottom: var(--spacing-sm);
  cursor: pointer;
  transition: all var(--transition-base);
}

.tag:hover,
.tag.active {
  background-color: var(--color-primary);
  color: white;
}

/* ========================================
   14. ALERTS & MESSAGES
   ======================================== */

.alert {
  padding: var(--spacing-lg);
  margin-bottom: var(--spacing-lg);
  border-radius: var(--radius-lg);
  border-left: 4px solid;
}

.alert-success {
  background-color: #dcfce7;
  border-color: var(--color-success);
  color: #166534;
}

.alert-error {
  background-color: #fee2e2;
  border-color: var(--color-error);
  color: #991b1b;
}

.alert-warning {
  background-color: #fef3c7;
  border-color: var(--color-warning);
  color: #92400e;
}

.alert-info {
  background-color: #dbeafe;
  border-color: var(--color-primary);
  color: #1e3a8a;
}

/* ========================================
   15. ANIMATIONS & TRANSITIONS
   ======================================== */

@keyframes fadeIn {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}

@keyframes slideUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes slideInLeft {
  from {
    opacity: 0;
    transform: translateX(-30px);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

@keyframes slideInRight {
  from {
    opacity: 0;
    transform: translateX(30px);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

@keyframes pulse {
  0%, 100% {
    opacity: 1;
  }
  50% {
    opacity: 0.5;
  }
}

.fade-in {
  animation: fadeIn var(--transition-base) ease-in-out;
}

.slide-up {
  animation: slideUp var(--transition-base) ease-in-out;
}

.scroll-reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: all var(--transition-base);
}

.scroll-reveal.revealed {
  opacity: 1;
  transform: translateY(0);
}

/* ========================================
   16. BUTTONS & INTERACTIVE ELEMENTS
   ======================================== */

.input-group {
  display: flex;
  gap: var(--spacing-sm);
}

.input-group input {
  flex: 1;
}

.input-group .btn {
  margin: 0;
}

.search-input {
  position: relative;
}

.search-input input {
  padding-left: var(--spacing-lg);
}

.search-icon {
  position: absolute;
  left: var(--spacing-md);
  top: 50%;
  transform: translateY(-50%);
  color: var(--color-text-lighter);
}

/* ========================================
   17. BACK TO TOP BUTTON
   ======================================== */

.back-to-top {
  position: fixed;
  bottom: var(--spacing-xl);
  right: var(--spacing-xl);
  width: 50px;
  height: 50px;
  background-color: var(--color-primary);
  color: white;
  border: none;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--font-size-xl);
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition-base);
  z-index: var(--z-dropdown);
}

.back-to-top.visible {
  opacity: 1;
  visibility: visible;
}

.back-to-top:hover {
  background-color: var(--color-accent);
  transform: translateY(-5px);
}

/* ========================================
   18. FILTER & SEARCH
   ======================================== */

.filter-group {
  display: flex;
  gap: var(--spacing-md);
  flex-wrap: wrap;
  margin-bottom: var(--spacing-xl);
}

.filter-item {
  padding: var(--spacing-sm) var(--spacing-lg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-full);
  background-color: var(--color-bg-light);
  color: var(--color-text-dark);
  cursor: pointer;
  transition: all var(--transition-base);
  font-size: var(--font-size-sm);
}

.filter-item:hover,
.filter-item.active {
  background-color: var(--color-primary);
  color: white;
  border-color: var(--color-primary);
}

.search-results {
  margin-top: var(--spacing-xl);
}

.search-result-item {
  padding: var(--spacing-lg);
  border-bottom: 1px solid var(--color-border);
  transition: all var(--transition-base);
}

.search-result-item:hover {
  background-color: var(--color-bg-gray);
  padding-left: var(--spacing-xl);
}

.search-result-title {
  color: var(--color-primary);
  font-weight: var(--font-weight-bold);
  margin-bottom: var(--spacing-sm);
}

.search-result-type {
  display: inline-block;
  background-color: var(--color-bg-gray);
  color: var(--color-primary);
  padding: var(--spacing-xs) var(--spacing-md);
  border-radius: var(--radius-md);
  font-size: var(--font-size-xs);
  font-weight: var(--font-weight-semibold);
  margin-bottom: var(--spacing-sm);
}

.no-results {
  text-align: center;
  padding: var(--spacing-3xl) var(--spacing-md);
  color: var(--color-text-light);
}

/* ========================================
   19. CONTENT HELPERS
   ======================================== */

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

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

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

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

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

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

.text-accent {
  color: var(--color-accent);
}

.text-sm {
  font-size: var(--font-size-sm);
}

.text-lg {
  font-size: var(--font-size-lg);
}

.text-bold {
  font-weight: var(--font-weight-bold);
}

/* Margin Utilities */
.mt-sm { margin-top: var(--spacing-sm); }
.mt-md { margin-top: var(--spacing-md); }
.mt-lg { margin-top: var(--spacing-lg); }
.mt-xl { margin-top: var(--spacing-xl); }
.mt-2xl { margin-top: var(--spacing-2xl); }

.mb-sm { margin-bottom: var(--spacing-sm); }
.mb-md { margin-bottom: var(--spacing-md); }
.mb-lg { margin-bottom: var(--spacing-lg); }
.mb-xl { margin-bottom: var(--spacing-xl); }
.mb-2xl { margin-bottom: var(--spacing-2xl); }

.mx-auto { margin-left: auto; margin-right: auto; }

/* Padding Utilities */
.p-lg { padding: var(--spacing-lg); }
.p-xl { padding: var(--spacing-xl); }
.px-sm { padding-left: var(--spacing-sm); padding-right: var(--spacing-sm); }
.px-md { padding-left: var(--spacing-md); padding-right: var(--spacing-md); }
.py-lg { padding-top: var(--spacing-lg); padding-bottom: var(--spacing-lg); }
.py-xl { padding-top: var(--spacing-xl); padding-bottom: var(--spacing-xl); }

.max-w-sm { max-width: 500px; }
.max-w-md { max-width: 700px; }
.max-w-lg { max-width: 900px; }

/* Flexbox Utilities */
.items-center { align-items: center; }
.justify-center { justify-content: center; }
.flex-1 { flex: 1; }

/* Display & Layout */
.list-none { list-style: none; padding: 0; }
.inline-block { display: inline-block; }
.block { display: block; }

/* Text & Color */
.text-light { color: rgba(255, 255, 255, 0.8); }
.text-lighter { color: rgba(255, 255, 255, 0.6); }
.text-muted-alt { color: var(--color-text-light); }
.line-height-tight { line-height: 1; }
.color-primary { color: var(--color-primary); }
.h3-primary { color: var(--color-primary); }
.h4-primary { color: var(--color-primary); }
.m-zero { margin: 0; }
.p-box { padding: var(--spacing-lg); }
.b-bottom { border-bottom: 1px solid var(--color-border); }
.faq-item {
  padding: var(--spacing-lg);
  border-bottom: 1px solid var(--color-border);
}
.faq-item h4 {
  margin-top: 0;
  color: var(--color-primary);
}
.faq-item p {
  margin: 0;
  color: var(--color-text-light);
}
.error-required { color: var(--color-error); }

/* Font Sizes - Large Emoji/Icons */
.text-6xl { font-size: 3rem; }
.text-8xl { font-size: 120px; }
.text-9xl { font-size: 150px; }

/* Margin Utilities - Additional */
.m-auto { margin: 0 auto; }
.m-2xl-auto { margin: var(--spacing-2xl) auto; }
.mb-3xl { margin-bottom: var(--spacing-3xl); }

/* Gap Utilities */
.gap-2xl { gap: var(--spacing-2xl); }

/* Combined Layout Classes */
.flex-center-wrap { 
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
}

.flex-between-center {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.section-spacing {
  margin-top: var(--spacing-2xl);
}

.section-divider-auto {
  margin: var(--spacing-2xl) auto;
}

.form-max-width {
  max-width: 700px;
  margin: 0 auto;
}

.grid-2-with-gap {
  gap: var(--spacing-2xl);
  margin-bottom: var(--spacing-3xl);
}

/* ========================================
   20. RESPONSIVE DESIGN
   ======================================== */

@media (max-width: 1024px) {
  :root {
    --font-size-5xl: 2.25rem;
    --font-size-4xl: 1.875rem;
    --font-size-3xl: 1.5rem;
  }
  
  .grid-cols-4 {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .grid-cols-3 {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  :root {
    --spacing-3xl: 2rem;
    --spacing-4xl: 3rem;
    --font-size-5xl: 1.875rem;
    --font-size-4xl: 1.5rem;
    --font-size-3xl: 1.25rem;
  }
  
  section {
    padding: var(--spacing-2xl) 0;
  }
  
  section.hero {
    padding: var(--spacing-3xl) 0;
  }
  
  .container {
    padding: 0 var(--spacing-md);
  }
  
  .grid-cols-4,
  .grid-cols-3,
  .grid-cols-2 {
    grid-template-columns: 1fr;
  }
  
  .footer-content {
    grid-template-columns: 1fr;
  }
  
  .primary-actions .primary-link,
  .drawer-links a {
    padding: var(--spacing-lg) var(--spacing-md);
  }
  
  .back-to-top {
    bottom: var(--spacing-lg);
    right: var(--spacing-lg);
    width: 45px;
    height: 45px;
  }
  
  table {
    font-size: var(--font-size-sm);
  }
  
  th, td {
    padding: var(--spacing-sm);
  }
  
  .input-group {
    flex-direction: column;
  }
}

@media (max-width: 480px) {
  :root {
    --spacing-2xl: 1.5rem;
    --spacing-xl: 1rem;
    --font-size-4xl: 1.25rem;
    --font-size-3xl: 1.125rem;
    --font-size-2xl: 1rem;
  }
  
  body {
    font-size: 15px;
  }
  
  h1 {
    font-size: var(--font-size-4xl);
  }
  
  h2 {
    font-size: var(--font-size-3xl);
  }
  
  .breadcrumbs {
    gap: var(--spacing-xs);
  }
  
  .card-meta {
    flex-direction: column;
  }
}
/* Legal pages layout */
.legal-container {
  max-width: 960px;
  margin: 0 auto;
  padding: 3rem 1rem 4rem;
}

.legal-section {
  background-color: var(--color-bg-light);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  padding: 2rem;
  box-shadow: var(--shadow-sm);
}

.legal-heading {
  font-size: var(--font-size-3xl);
  margin-bottom: var(--spacing-md);
  color: var(--color-primary-dark);
}

.legal-updated-date {
  font-size: var(--font-size-sm);
  color: var(--color-text-lighter);
  margin-bottom: var(--spacing-lg);
}

.legal-section h2,
.legal-section h3 {
  margin-top: var(--spacing-lg);
  margin-bottom: var(--spacing-sm);
  color: var(--color-text-dark);
}

.legal-section p {
  margin-bottom: var(--spacing-md);
  color: var(--color-text-light);
}

@media (max-width: 768px) {
  .legal-container {
    padding: 2rem 0.75rem 3rem;
  }

  .legal-section {
    padding: 1.25rem;
  }

  .legal-heading {
    font-size: var(--font-size-2xl);
  }
}

@media (max-width: 480px) {
  .legal-container {
    padding: 1.5rem 0.5rem 2rem;
  }

  .legal-section {
    padding: 1rem;
  }

  .legal-heading {
    font-size: var(--font-size-xl);
  }
}

/* ========================================
   15. UTILITY CLASSES FOR INLINE STYLES
   ======================================== */

.mt-0 { margin-top: 0; }
.text-secondary { color: var(--color-text-secondary); }
.text-secondary-sm { color: var(--color-text-secondary); font-size: var(--font-size-sm); }
.color-accent { color: var(--color-accent); }
.font-size-5xl { font-size: 5rem; }
.flex { display: flex; }
.flex-gap-lg { display: flex; gap: var(--spacing-lg); }
.flex-gap-lg-mb-lg { display: flex; gap: var(--spacing-lg); margin-bottom: var(--spacing-lg); }
.align-items-center { align-items: center; }
.flex-shrink-0 { flex-shrink: 0; }
.font-size-1-5rem { font-size: 1.5rem; }
.margin-0 { margin: 0; }
.space-y-lg { margin-bottom: var(--spacing-lg); }
.callout { background: var(--color-bg-alt); padding: var(--spacing-2xl); border-radius: var(--radius-md); border-left: 4px solid var(--color-accent); }
.hero-gradient-accent { background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-accent) 100%); color: white; }
.grid-gap-2xl-center { gap: var(--spacing-2xl); align-items: center; }
.icon-large { font-size: 1.5rem; flex-shrink: 0; }
.mb-sm-m0 { margin: 0 0 var(--spacing-sm) 0; }
.text-secondary-m0 { color: var(--color-text-secondary); margin: 0; }
.error-code { font-size: 5rem; margin-bottom: var(--spacing-md); font-weight: bold; color: var(--color-accent); }
.text-center-mb-3xl { text-align: center; margin-bottom: var(--spacing-3xl); }
.text-secondary-base-mb-lg { color: var(--color-text-secondary); font-size: var(--font-size-base); margin-bottom: var(--spacing-lg); }
.grid-mb-2xl { margin-bottom: var(--spacing-2xl); }
.mt-0-color-primary { margin-top: 0; color: var(--color-primary); }
.border-bottom { border-bottom: 1px solid var(--color-border); }
.bg-alt { background: var(--color-bg-alt); }
.font-medium { font-weight: var(--font-weight-medium); }
.input-newsletter { width: 100%; padding: var(--spacing-md); border: 2px solid var(--color-border); border-radius: var(--radius-sm); font-size: var(--font-size-base); }
.text-xs { font-size: var(--font-size-xs); }
.card-link { display: block; text-decoration: none; color: inherit; }
.flex-between-start { display: flex; justify-content: space-between; align-items: start; }
.whitespace-nowrap { white-space: nowrap; }
.ml-lg { margin-left: var(--spacing-lg); }
.input-search { width: 100%; padding: var(--spacing-lg); border: 2px solid var(--color-border); border-radius: var(--radius-sm); font-size: var(--font-size-base); }
.cursor-pointer { cursor: pointer; }
.p-3xl { padding: var(--spacing-3xl); }
.m-md-0 { margin: var(--spacing-md) 0; }