/* ════════════════════════════════════════════════════════════════════
   R18 — WORLD-CLASS MOBILE-FIRST DESIGN SYSTEM
   Deployed across all 10 portfolio domains
   Features: touch ripple, autofill override, dark mode transition,
   sticky CTA, bottom sheet, scroll snap, viewport units,
   container queries, offline indicator, print styles, haptic
   ════════════════════════════════════════════════════════════════════ */

/* ── 0. CSS CUSTOM PROPERTIES (DESIGN TOKENS) ──────────────────── */
:root {
  --ux-accent: #2563eb;
  --ux-accent-hover: #1d4ed8;
  --ux-accent-ghost: rgba(37, 99, 235, 0.08);
  --ux-accent-ghost-hover: rgba(37, 99, 235, 0.14);
  --ux-surface: #ffffff;
  --ux-surface-raised: #f8fafc;
  --ux-border: #e2e8f0;
  --ux-border-hover: #cbd5e1;
  --ux-text: #0f172a;
  --ux-text-secondary: #475569;
  --ux-text-muted: #94a3b8;
  --ux-radius-sm: 0.5rem;
  --ux-radius: 0.75rem;
  --ux-radius-lg: 1rem;
  --ux-radius-xl: 1.5rem;
  --ux-radius-full: 9999px;
  --ux-shadow-sm: 0 1px 2px rgba(15, 23, 42, 0.04);
  --ux-shadow: 0 1px 3px rgba(15, 23, 42, 0.06), 0 4px 16px rgba(15, 23, 42, 0.04);
  --ux-shadow-lg: 0 4px 24px rgba(15, 23, 42, 0.08), 0 8px 40px rgba(15, 23, 42, 0.04);
  --ux-shadow-xl: 0 8px 40px rgba(15, 23, 42, 0.1), 0 16px 64px rgba(15, 23, 42, 0.05);
  --ux-transition: 200ms cubic-bezier(0.4, 0, 0.2, 1);
  --ux-transition-slow: 350ms cubic-bezier(0.16, 1, 0.3, 1);
  --ux-nav-height: 64px;
  /* R18 — mobile bottom bar */
  --ux-bottom-bar-height: 0px;
}

/* ── 1. CSS RESET & BOX-SIZING ──────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

/* ── 2. MOBILE-FIRST TYPOGRAPHY ─────────────────────────────────── */
html {
  font-size: 100%;
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  font-size: 1.0625rem;
  line-height: 1.65;
  color: var(--ux-text);
  background: var(--ux-surface);
  overflow-x: hidden;
  min-height: 100vh;
  min-height: 100dvh;
  /* R18 — theme transition */
  transition: background-color 0.3s ease, color 0.3s ease;
}
@media (prefers-reduced-motion: reduce) {
  body { transition: none; }
}

/* ── 3. FLUID RESPONSIVE HEADING SCALE ──────────────────────────── */
h1 { font-size: clamp(1.75rem, 5vw, 3rem); line-height: 1.12; letter-spacing: -0.025em; font-weight: 800; }
h2 { font-size: clamp(1.375rem, 4vw, 2.25rem); line-height: 1.2; letter-spacing: -0.015em; font-weight: 700; }
h3 { font-size: clamp(1.125rem, 3vw, 1.5rem); line-height: 1.3; font-weight: 700; }
h4 { font-size: 1.125rem; line-height: 1.35; font-weight: 600; }
h1, h2, h3, h4, h5, h6 { margin-bottom: 0.5em; }

p { margin-bottom: 1.25em; max-width: 65ch; }

/* ── 4. LINKS ───────────────────────────────────────────────────── */
a {
  color: var(--ux-accent);
  text-underline-offset: 0.2em;
  text-decoration-thickness: 0.08em;
  transition: color var(--ux-transition);
  touch-action: manipulation;
  -webkit-tap-highlight-color: transparent;
}
a:hover { color: var(--ux-accent-hover); }

/* ── 5. TOUCH-FRIENDLY INTERACTIVE TARGETS ──────────────────────── */
button, .btn, [role="button"],
a.button, a.btn, .cta, input[type="submit"],
input[type="button"], select {
  min-height: 44px;
  min-width: 44px;
  padding: 0.625rem 1.25rem;
  font-size: 1rem;
  font-family: inherit;
  font-weight: 600;
  cursor: pointer;
  border-radius: var(--ux-radius);
  border: none;
  transition: all var(--ux-transition), background-color 0.3s ease;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  text-decoration: none;
  touch-action: manipulation;
  -webkit-tap-highlight-color: transparent;
  user-select: none;
  -webkit-user-select: none;
}
button:active, .btn:active, a.btn:active { transform: scale(0.97); }
@media (prefers-reduced-motion: reduce) {
  button, .btn, [role="button"], a.button, a.btn { transition: none; }
}

/* ── 6. GRADIENT CTA BUTTONS ────────────────────────────────────── */
.ux-cta-primary, a.ux-cta-primary {
  background: linear-gradient(135deg, var(--ux-accent) 0%, #4f46e5 100%);
  color: #fff;
  padding: 0.75rem 2rem;
  font-weight: 700;
  border-radius: var(--ux-radius-full);
  box-shadow: 0 2px 8px rgba(37, 99, 235, 0.3);
  letter-spacing: -0.01em;
}
.ux-cta-primary:hover {
  box-shadow: 0 4px 20px rgba(37, 99, 235, 0.4);
  transform: translateY(-1px);
  filter: brightness(1.08);
}
.ux-cta-primary:active { transform: translateY(0) scale(0.97); }
@media (prefers-reduced-motion: reduce) {
  .ux-cta-primary, .ux-cta-primary:hover { transition: none; transform: none; }
}

/* ── 7. GLASSMORPHISM CARDS ─────────────────────────────────────── */
.ux-glass-card {
  background: rgba(255, 255, 255, 0.7);
  backdrop-filter: blur(16px) saturate(180%);
  -webkit-backdrop-filter: blur(16px) saturate(180%);
  border: 1px solid rgba(255, 255, 255, 0.5);
  border-radius: var(--ux-radius-lg);
  box-shadow: var(--ux-shadow-lg);
  transition: all var(--ux-transition-slow), background-color 0.3s ease;
}
.ux-glass-card:hover {
  background: rgba(255, 255, 255, 0.82);
  box-shadow: var(--ux-shadow-xl);
  transform: translateY(-2px);
}
@media (prefers-reduced-transparency: reduce) {
  .ux-glass-card {
    background: var(--ux-surface);
    backdrop-filter: none;
    -webkit-backdrop-filter: none;
  }
}
@media (prefers-reduced-motion: reduce) {
  .ux-glass-card, .ux-glass-card:hover { transition: none; transform: none; }
}

/* ── 8. STANDARD CARDS ──────────────────────────────────────────── */
.ux-card {
  background: var(--ux-surface);
  border: 1px solid var(--ux-border);
  border-radius: var(--ux-radius-lg);
  padding: 1.5rem;
  box-shadow: var(--ux-shadow-sm);
  transition: all var(--ux-transition-slow);
}
.ux-card:hover {
  border-color: var(--ux-border-hover);
  box-shadow: var(--ux-shadow);
  transform: translateY(-1px);
}
.ux-card:active { transform: translateY(0); }
@media (prefers-reduced-motion: reduce) {
  .ux-card, .ux-card:hover { transition: none; transform: none; }
}

/* ── 9. BADGE PILLS ─────────────────────────────────────────────── */
.ux-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.375rem;
  padding: 0.25rem 0.75rem;
  font-size: 0.8125rem;
  font-weight: 600;
  border-radius: var(--ux-radius-full);
  white-space: nowrap;
}
.ux-badge-accent {
  background: var(--ux-accent-ghost);
  color: var(--ux-accent);
  border: 1px solid rgba(37, 99, 235, 0.15);
}
.ux-badge-success {
  background: rgba(16, 185, 129, 0.1);
  color: #065f46;
  border: 1px solid rgba(16, 185, 129, 0.2);
}
.ux-badge-warning {
  background: rgba(245, 158, 11, 0.1);
  color: #92400e;
  border: 1px solid rgba(245, 158, 11, 0.2);
}
.ux-badge-danger {
  background: rgba(239, 68, 68, 0.1);
  color: #991b1b;
  border: 1px solid rgba(239, 68, 68, 0.2);
}

/* ── 10. SKELETON LOADING ───────────────────────────────────────── */
.ux-skeleton {
  background: linear-gradient(90deg, var(--ux-border) 25%, #f1f5f9 50%, var(--ux-border) 75%);
  background-size: 200% 100%;
  animation: ux-shimmer 1.5s ease-in-out infinite;
  border-radius: var(--ux-radius-sm);
}
@keyframes ux-shimmer {
  0% { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}

/* ── 11. STAGGERED ENTRY ANIMATIONS ─────────────────────────────── */
.ux-stagger > * {
  opacity: 0;
  transform: translateY(24px);
  animation: ux-fadeUp 0.6s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}
.ux-stagger > *:nth-child(1) { animation-delay: 0ms; }
.ux-stagger > *:nth-child(2) { animation-delay: 80ms; }
.ux-stagger > *:nth-child(3) { animation-delay: 160ms; }
.ux-stagger > *:nth-child(4) { animation-delay: 240ms; }
.ux-stagger > *:nth-child(5) { animation-delay: 320ms; }
.ux-stagger > *:nth-child(6) { animation-delay: 400ms; }
.ux-stagger > *:nth-child(7) { animation-delay: 480ms; }
.ux-stagger > *:nth-child(8) { animation-delay: 560ms; }

@keyframes ux-fadeUp {
  to { opacity: 1; transform: translateY(0); }
}

/* ── 12. READING PROGRESS BAR ───────────────────────────────────── */
#ux-reading-progress {
  position: fixed;
  top: 0;
  left: 0;
  height: 3px;
  width: 0%;
  background: linear-gradient(90deg, var(--ux-accent), #4f46e5);
  z-index: 99999;
  transition: width 50ms linear;
  pointer-events: none;
}

/* ── 13. BACK-TO-TOP BUTTON ─────────────────────────────────────── */
#ux-back-to-top {
  position: fixed;
  bottom: clamp(1.5rem, 4vw, 2rem);
  right: clamp(1.5rem, 4vw, 2rem);
  width: 48px;
  height: 48px;
  min-width: 48px;
  min-height: 48px;
  border-radius: var(--ux-radius-full);
  background: var(--ux-surface);
  color: var(--ux-text);
  border: 1px solid var(--ux-border);
  font-size: 1.25rem;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--ux-shadow-lg);
  cursor: pointer;
  opacity: 0;
  transform: translateY(8px);
  transition: opacity var(--ux-transition-slow), transform var(--ux-transition-slow), background-color 0.3s ease, color 0.3s ease;
  z-index: 99998;
  pointer-events: none;
  padding: 0;
}
#ux-back-to-top.visible {
  opacity: 1;
  transform: translateY(0);
  pointer-events: auto;
}
#ux-back-to-top:hover {
  box-shadow: var(--ux-shadow-xl);
  transform: translateY(-2px);
  border-color: var(--ux-accent);
}
#ux-back-to-top:active { transform: translateY(0) scale(0.95); }

/* ── 14. SAFE-AREA INSETS (iOS notched + Dynamic Island) ────────── */
@supports (padding-bottom: env(safe-area-inset-bottom)) {
  body {
    padding-bottom: calc(env(safe-area-inset-bottom) + var(--ux-bottom-bar-height));
    padding-left: env(safe-area-inset-left);
    padding-right: env(safe-area-inset-right);
  }
  #ux-back-to-top {
    bottom: calc(clamp(1.5rem, 4vw, 2rem) + env(safe-area-inset-bottom));
    right: calc(clamp(1.5rem, 4vw, 2rem) + env(safe-area-inset-right));
  }
  /* R18 — sticky CTA respects safe area */
  .ux-sticky-cta {
    padding-bottom: calc(1rem + env(safe-area-inset-bottom));
  }
  /* R18 — bottom sheet respects safe area */
  .ux-bottom-sheet {
    padding-bottom: env(safe-area-inset-bottom);
  }
}

/* ── 15. FOCUS STATES ───────────────────────────────────────────── */
:focus-visible {
  outline: 3px solid var(--ux-accent);
  outline-offset: 3px;
  border-radius: 4px;
}
:focus:not(:focus-visible) { outline: none; }

/* ── 16. SKIP-TO-CONTENT ────────────────────────────────────────── */
.ux-skip-link {
  position: absolute;
  top: -100%;
  left: 0.75rem;
  padding: 0.5rem 1rem;
  background: var(--ux-accent);
  color: #fff;
  font-weight: 700;
  border-radius: var(--ux-radius-sm);
  z-index: 100000;
  transition: top 0.15s ease;
}
.ux-skip-link:focus { top: 0.75rem; }

/* ── 17. IMAGES — CLS PREVENTION ────────────────────────────────── */
img, video, iframe, embed { max-width: 100%; height: auto; display: block; }
img:not([width]):not([height]) { aspect-ratio: 16/9; }
img[loading="lazy"] { opacity: 0; transition: opacity 0.3s ease; }
img[loading="lazy"].loaded { opacity: 1; }

/* ── 18. FORM ELEMENTS ──────────────────────────────────────────── */
input, textarea, select {
  font-size: 1rem;
  font-family: inherit;
  padding: 0.75rem 0.875rem;
  border: 1.5px solid var(--ux-border);
  border-radius: var(--ux-radius);
  width: 100%;
  background: var(--ux-surface);
  color: var(--ux-text);
  transition: border-color var(--ux-transition), box-shadow var(--ux-transition), background-color 0.3s ease;
}
input:focus, textarea:focus, select:focus {
  border-color: var(--ux-accent);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.12);
  outline: none;
}
label {
  display: block;
  margin-bottom: 0.375rem;
  font-weight: 600;
  font-size: 0.9375rem;
  color: var(--ux-text);
}
::placeholder { color: var(--ux-text-muted); opacity: 1; }

/* ── R18 — AUTOFILL OVERRIDE (kill Chrome/Safari yellow bg) ─────── */
input:-webkit-autofill,
input:-webkit-autofill:hover,
input:-webkit-autofill:focus,
input:-webkit-autofill:active {
  -webkit-box-shadow: 0 0 0 30px var(--ux-surface) inset !important;
  -webkit-text-fill-color: var(--ux-text) !important;
  caret-color: var(--ux-text);
  transition: background-color 5000s ease-in-out 0s;
}
@media (prefers-color-scheme: dark) {
  input:-webkit-autofill,
  input:-webkit-autofill:hover,
  input:-webkit-autofill:focus,
  input:-webkit-autofill:active {
    -webkit-box-shadow: 0 0 0 30px var(--ux-surface) inset !important;
    -webkit-text-fill-color: var(--ux-text) !important;
  }
}

/* ── R18 — TOUCH RIPPLE EFFECT ──────────────────────────────────── */
.ux-ripple {
  position: relative;
  overflow: hidden;
}
.ux-ripple::after {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(circle, rgba(255,255,255,0.3) 10%, transparent 10%);
  background-position: center;
  background-repeat: no-repeat;
  opacity: 0;
  transform: scale(10, 10);
  transition: transform 0.5s, opacity 0.6s;
  pointer-events: none;
}
.ux-ripple:active::after {
  opacity: 1;
  transform: scale(0, 0);
  transition: 0s;
}

/* ── 19. SPACING ────────────────────────────────────────────────── */
section, .section { padding: clamp(2.5rem, 6vw, 5rem) clamp(1rem, 4vw, 2rem); }

/* ── R18 — VIEWPORT-AWARE SECTIONS ───────────────────────────────── */
.ux-section-full { min-height: 100dvh; display: flex; align-items: center; }
.ux-section-narrow { max-width: 800px; margin: 0 auto; }

/* ── 20. DIVIDERS ───────────────────────────────────────────────── */
.ux-divider {
  height: 1px;
  background: var(--ux-border);
  width: 100%;
}
.ux-divider-accent {
  height: 3px;
  width: 48px;
  background: var(--ux-accent);
  border-radius: 2px;
  margin-bottom: 1.5rem;
}

/* ── 21. GRADIENT TEXT ──────────────────────────────────────────── */
.ux-gradient-text {
  background: linear-gradient(135deg, var(--ux-accent), #4f46e5);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* ── 22. GRADIENT ORB DECORATIONS ───────────────────────────────── */
.ux-orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(80px);
  opacity: 0.12;
  pointer-events: none;
  z-index: -1;
}
.ux-orb-accent {
  background: radial-gradient(circle, var(--ux-accent) 0%, transparent 70%);
}

/* ── 23. SCROLLBAR HIDE ─────────────────────────────────────────── */
.ux-scrollbar-hide {
  -ms-overflow-style: none;
  scrollbar-width: none;
}
.ux-scrollbar-hide::-webkit-scrollbar { display: none; }

/* ── 24. MOBILE NAV OVERLAY ─────────────────────────────────────── */
body.nav-open { overflow: hidden; }
[data-mobile-nav] {
  display: none;
  position: fixed;
  inset: 0;
  top: var(--ux-nav-height);
  background: var(--ux-surface);
  z-index: 99997;
  overflow-y: auto;
  padding: 1.5rem;
  opacity: 0;
  transform: translateY(-8px);
  transition: opacity var(--ux-transition), transform var(--ux-transition), background-color 0.3s ease;
}
[data-mobile-nav].open {
  display: block;
  opacity: 1;
  transform: translateY(0);
}
/* R18 — mobile nav swipe-down-to-close hint */
.ux-nav-swipe-hint {
  width: 36px;
  height: 5px;
  background: var(--ux-border);
  border-radius: 3px;
  margin: 0 auto 1.25rem;
}

/* ── 25. ACCORDIONS ─────────────────────────────────────────────── */
[data-accordion-trigger] {
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  text-align: left;
  padding: 0.75rem 0;
  font-weight: 600;
  border: none;
  background: none;
  font-size: 1rem;
  color: var(--ux-text);
  border-bottom: 1px solid var(--ux-border);
  transition: color var(--ux-transition);
}
[data-accordion-trigger]:hover { color: var(--ux-accent); }
[data-accordion-trigger]::after {
  content: '+';
  font-size: 1.25rem;
  transition: transform var(--ux-transition);
  min-width: 24px;
  text-align: center;
}
[data-accordion-trigger][aria-expanded="true"]::after { content: '\2212'; }
[data-accordion] {
  max-height: 0;
  overflow: hidden;
  transition: max-height var(--ux-transition-slow);
}
[data-accordion].open { max-height: 2000px; }

/* ── 26. PULSE ANIMATION ────────────────────────────────────────── */
@keyframes ux-pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.6; }
}
.ux-pulse { animation: ux-pulse 2s ease-in-out infinite; }

/* ── 27. RESPONSIVE TABLE WRAPPER ───────────────────────────────── */
.ux-table-wrap {
  width: 100%;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

/* ════════════════════════════════════════════════════════════════════
   R18 — NEW MOBILE-FIRST FEATURES BELOW
   ════════════════════════════════════════════════════════════════════ */

/* ── 28. STICKY MOBILE CTA BAR ───────────────────────────────────── */
.ux-sticky-cta {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  padding: 0.75rem 1rem;
  background: var(--ux-surface);
  border-top: 1px solid var(--ux-border);
  z-index: 99996;
  display: none;
  box-shadow: 0 -2px 16px rgba(15, 23, 42, 0.06);
  transition: background-color 0.3s ease, border-color 0.3s ease;
}
.ux-sticky-cta.visible { display: flex; align-items: center; gap: 0.75rem; }
.ux-sticky-cta .ux-cta-primary { flex: 1; }

/* ── 29. BOTTOM SHEET ───────────────────────────────────────────── */
.ux-bottom-sheet-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.5);
  z-index: 99990;
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--ux-transition-slow);
}
.ux-bottom-sheet-overlay.open {
  opacity: 1;
  pointer-events: auto;
}
.ux-bottom-sheet {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  max-height: 85dvh;
  background: var(--ux-surface);
  border-radius: var(--ux-radius-xl) var(--ux-radius-xl) 0 0;
  z-index: 99991;
  transform: translateY(100%);
  transition: transform var(--ux-transition-slow);
  overflow-y: auto;
  padding: 0.5rem 1.25rem 1.5rem;
  box-shadow: 0 -4px 24px rgba(15, 23, 42, 0.15);
}
.ux-bottom-sheet.open { transform: translateY(0); }

/* ── 30. SCROLL SNAP ─────────────────────────────────────────────── */
.ux-snap-x {
  display: flex;
  overflow-x: auto;
  scroll-snap-type: x mandatory;
  -webkit-overflow-scrolling: touch;
  scroll-behavior: smooth;
  gap: 1rem;
}
.ux-snap-x > * {
  scroll-snap-align: start;
  flex: 0 0 auto;
}
.ux-snap-y {
  overflow-y: auto;
  scroll-snap-type: y mandatory;
  scroll-behavior: smooth;
}
.ux-snap-y > * { scroll-snap-align: start; }

/* ── 31. MOBILE CAROUSEL HINT ────────────────────────────────────── */
.ux-carousel {
  display: flex;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  gap: 0.75rem;
  padding-bottom: 0.5rem;
  scroll-behavior: smooth;
}
.ux-carousel > * {
  flex: 0 0 auto;
  min-width: 280px;
  max-width: 340px;
}
@media (max-width: 480px) {
  .ux-carousel > * { min-width: 240px; }
}

/* ── 32. FLOATING ACTION BUTTON ─────────────────────────────────── */
.ux-fab {
  position: fixed;
  bottom: clamp(1.5rem, 4vw, 2rem);
  right: clamp(1.5rem, 4vw, 2rem);
  width: 56px;
  height: 56px;
  border-radius: var(--ux-radius-full);
  background: var(--ux-accent);
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 4px 16px rgba(37, 99, 235, 0.35);
  z-index: 99995;
  font-size: 1.5rem;
  border: none;
  cursor: pointer;
  transition: transform var(--ux-transition), box-shadow var(--ux-transition);
}
.ux-fab:hover { transform: scale(1.06); box-shadow: 0 6px 24px rgba(37, 99, 235, 0.45); }
.ux-fab:active { transform: scale(0.95); }

/* ── 33. TOAST NOTIFICATIONS ────────────────────────────────────── */
.ux-toast-container {
  position: fixed;
  top: 1rem;
  right: 1rem;
  z-index: 99999;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  pointer-events: none;
  max-width: calc(100vw - 2rem);
}
.ux-toast {
  padding: 0.75rem 1.25rem;
  background: var(--ux-surface);
  border: 1px solid var(--ux-border);
  border-radius: var(--ux-radius);
  box-shadow: var(--ux-shadow-lg);
  font-size: 0.9375rem;
  font-weight: 500;
  pointer-events: auto;
  animation: ux-toast-in 0.35s cubic-bezier(0.16, 1, 0.3, 1) forwards;
  max-width: 380px;
}
.ux-toast.removing {
  animation: ux-toast-out 0.25s ease forwards;
}
@keyframes ux-toast-in {
  from { opacity: 0; transform: translateX(20px); }
  to { opacity: 1; transform: translateX(0); }
}
@keyframes ux-toast-out {
  from { opacity: 1; transform: translateX(0); }
  to { opacity: 0; transform: translateX(20px); }
}

/* ── 34. RESPONSIVE GRID UTILITY ─────────────────────────────────── */
.ux-grid {
  display: grid;
  gap: 1.5rem;
}
.ux-grid-2 { grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); }
.ux-grid-3 { grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); }
.ux-grid-4 { grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); }
@media (max-width: 480px) {
  .ux-grid-2, .ux-grid-3, .ux-grid-4 { grid-template-columns: 1fr; }
}

/* ── 35. OFFLINE INDICATOR ──────────────────────────────────────── */
.ux-offline-bar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  padding: 0.5rem;
  text-align: center;
  font-size: 0.875rem;
  font-weight: 600;
  background: #f59e0b;
  color: #78350f;
  z-index: 100001;
  transform: translateY(-100%);
  transition: transform 0.3s ease;
}
.ux-offline-bar.visible { transform: translateY(0); }

/* ── 36. CONTAINER QUERIES (modern browsers) ─────────────────────── */
@supports (container-type: inline-size) {
  .ux-container-query { container-type: inline-size; }
  @container (min-width: 500px) {
    .ux-cq-card { display: flex; gap: 1.5rem; }
  }
}

/* ── 37. SCROLL-DRIVEN ANIMATIONS (modern browsers) ──────────────── */
@supports (animation-timeline: scroll()) {
  .ux-scroll-reveal {
    animation: ux-reveal linear both;
    animation-timeline: view();
    animation-range: entry 0% entry 100%;
  }
  @keyframes ux-reveal {
    from { opacity: 0; transform: translateY(40px); }
    to { opacity: 1; transform: translateY(0); }
  }
}

/* ── 38. DATA SAVING MODE ───────────────────────────────────────── */
@media (prefers-reduced-data: reduce) {
  .ux-glass-card {
    backdrop-filter: none;
    -webkit-backdrop-filter: none;
  }
  .ux-orb { display: none; }
  img[loading="lazy"] { opacity: 1; } /* skip fade animation */
}

/* ── 39. HAPTIC FEEDBACK SUPPORT ─────────────────────────────────── */
@media (hover: none) and (pointer: coarse) {
  .ux-haptic:active {
    /* Devices that support haptic feedback will use this */
    -webkit-tap-highlight-color: rgba(37, 99, 235, 0.15);
  }
}

/* ── 40. PRINT STYLES ───────────────────────────────────────────── */
@media print {
  *, *::before, *::after { background: transparent !important; color: #000 !important; box-shadow: none !important; }
  body { font-size: 12pt; line-height: 1.5; }
  #ux-reading-progress, #ux-back-to-top, .ux-sticky-cta, .ux-fab,
  .ux-toast-container, .ux-offline-bar, [data-mobile-nav] { display: none !important; }
  a { text-decoration: underline; }
  a[href^="http"]::after { content: ' (' attr(href) ')'; font-size: 0.8em; }
}

/* ── 41. MOBILE BREAKPOINTS ─────────────────────────────────────── */
@media (max-width: 768px) {
  body { font-size: 1rem; line-height: 1.6; }
  h1 { font-size: clamp(1.5rem, 6vw, 2.5rem); }
  h2 { font-size: clamp(1.25rem, 5vw, 1.75rem); }
  section, .section { padding: 1.5rem 1rem; }
  .ux-card { padding: 1.25rem; }
  .ux-glass-card { border-radius: var(--ux-radius); }
  .ux-stagger > * { animation-duration: 0.45s; }
  .ux-stagger > *:nth-child(n+3) { animation-delay: 40ms; }
  /* R18 - mobile sticky CTA */
  .ux-sticky-cta { display: flex; }
  .ux-sticky-cta.visible { display: flex; }
}

@media (max-width: 480px) {
  .ux-cta-primary { padding: 0.625rem 1.5rem; font-size: 0.9375rem; }
  section, .section { padding: 1.25rem 0.875rem; }
}

/* ── 42. DARK MODE ──────────────────────────────────────────────── */
@media (prefers-color-scheme: dark) {
  :root {
    --ux-accent: #60a5fa;
    --ux-accent-hover: #93bbfd;
    --ux-accent-ghost: rgba(96, 165, 250, 0.12);
    --ux-accent-ghost-hover: rgba(96, 165, 250, 0.2);
    --ux-surface: #0f172a;
    --ux-surface-raised: #1e293b;
    --ux-border: #334155;
    --ux-border-hover: #475569;
    --ux-text: #f1f5f9;
    --ux-text-secondary: #94a3b8;
    --ux-text-muted: #64748b;
    --ux-shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.3);
    --ux-shadow: 0 1px 3px rgba(0, 0, 0, 0.4), 0 4px 16px rgba(0, 0, 0, 0.2);
    --ux-shadow-lg: 0 4px 24px rgba(0, 0, 0, 0.4), 0 8px 40px rgba(0, 0, 0, 0.2);
    --ux-shadow-xl: 0 8px 40px rgba(0, 0, 0, 0.5), 0 16px 64px rgba(0, 0, 0, 0.3);
  }
  body { background: var(--ux-surface); color: var(--ux-text); }
  input, textarea, select { background: var(--ux-surface-raised); border-color: var(--ux-border); color: var(--ux-text); }
  input:focus, textarea:focus, select:focus { border-color: var(--ux-accent); box-shadow: 0 0 0 3px rgba(96, 165, 250, 0.15); }
  .ux-glass-card {
    background: rgba(30, 41, 59, 0.7);
    border-color: rgba(148, 163, 184, 0.12);
    backdrop-filter: blur(16px) saturate(180%);
    -webkit-backdrop-filter: blur(16px) saturate(180%);
  }
  .ux-glass-card:hover { background: rgba(30, 41, 59, 0.85); }
  .ux-skeleton { background: linear-gradient(90deg, var(--ux-border) 25%, #1e293b 50%, var(--ux-border) 75%); background-size: 200% 100%; }
  .ux-badge-accent { background: rgba(96, 165, 250, 0.15); color: var(--ux-accent); }
  .ux-badge-success { background: rgba(52, 211, 153, 0.12); color: #6ee7b7; border-color: rgba(52, 211, 153, 0.2); }
  .ux-badge-warning { background: rgba(251, 191, 36, 0.12); color: #fcd34d; border-color: rgba(251, 191, 36, 0.2); }
  .ux-badge-danger { background: rgba(248, 113, 113, 0.12); color: #fca5a5; border-color: rgba(248, 113, 113, 0.2); }
  .ux-orb-accent { opacity: 0.08; }
  .ux-bottom-sheet-overlay { background: rgba(0, 0, 0, 0.7); }
}

@media (prefers-color-scheme: dark) and (max-width: 768px) {
  .ux-glass-card {
    background: rgba(15, 23, 42, 0.85);
  }
}

/* ── 43. REDUCED MOTION ─────────────────────────────────────────── */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
  .ux-stagger > * { opacity: 1; transform: none; animation: none; }
  .ux-stagger > *:nth-child(n) { animation-delay: 0ms; }
}