/* ============================================
   COLLECTIONS MANAGEMENT SYSTEM — DESIGN SYSTEM
   Version: 2.0 (FastAPI + Static HTML Edition)
   
   100% REM-based — ZERO px values
   Dark mode DEFAULT
   Mobile-first responsive
   WCAG 2.1 AA compliant
   ============================================ */

/* ============================================
   1. CSS CUSTOM PROPERTIES (Design Tokens)
   ============================================ */
:root {
  /* ---- Color Palette: Light Mode ---- */
  --bg-primary: #FFFFFF;
  --bg-secondary: #F9FAFB;
  --bg-tertiary: #F3F4F6;
  --bg-inverse: #111827;

  --text-primary: #111827;
  --text-secondary: #4B5563;
  --text-tertiary: #9CA3AF;
  --text-inverse: #F9FAFB;
  --text-link: #2563EB;
  --text-link-hover: #1D4ED8;

  --border-primary: #E5E7EB;
  --border-secondary: #D1D5DB;
  --border-focus: #2563EB;

  --surface-hover: #F3F4F6;
  --surface-active: #E5E7EB;

  /* ---- Brand / Accent ---- */
  --brand-50: #EFF6FF;
  --brand-100: #DBEAFE;
  --brand-200: #BFDBFE;
  --brand-500: #3B82F6;
  --brand-600: #2563EB;
  --brand-700: #1D4ED8;
  --brand-800: #1E40AF;

  /* ---- Semantic ---- */
  --success-50: #F0FDF4;
  --success-100: #DCFCE7;
  --success-500: #22C55E;
  --success-600: #16A34A;
  --success-700: #15803D;
  --success-900: #14532D;

  --warning-50: #FFFBEB;
  --warning-100: #FEF3C7;
  --warning-500: #F59E0B;
  --warning-600: #D97706;
  --warning-700: #B45309;
  --warning-900: #78350F;

  --error-50: #FEF2F2;
  --error-100: #FEE2E2;
  --error-500: #EF4444;
  --error-600: #DC2626;
  --error-700: #B91C1C;
  --error-900: #7F1D1D;

  --info-50: #EFF6FF;
  --info-100: #DBEAFE;
  --info-500: #3B82F6;
  --info-600: #2563EB;

  /* ---- Overlay / Backdrop ---- */
  --overlay-bg: rgba(0, 0, 0, 0.45);
  --overlay-bg-heavy: rgba(0, 0, 0, 0.6);

  /* ---- Spacing Scale ---- */
  --space-0: 0;
  --space-0-5: 0.125rem;
  --space-1: 0.25rem;
  --space-1-5: 0.375rem;
  --space-2: 0.5rem;
  --space-2-5: 0.625rem;
  --space-3: 0.75rem;
  --space-3-5: 0.875rem;
  --space-4: 1rem;
  --space-5: 1.25rem;
  --space-6: 1.5rem;
  --space-7: 1.75rem;
  --space-8: 2rem;
  --space-9: 2.25rem;
  --space-10: 2.5rem;
  --space-11: 2.75rem;
  --space-12: 3rem;
  --space-14: 3.5rem;
  --space-16: 4rem;
  --space-20: 5rem;
  --space-24: 6rem;
  --space-32: 8rem;

  /* ---- Typography ---- */
  --font-sans: 'Inter', ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  --font-mono: 'JetBrains Mono', ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;

  --text-xs: 0.75rem;
  --text-sm: 0.875rem;
  --text-base: 1rem;
  --text-lg: 1.125rem;
  --text-xl: 1.25rem;
  --text-2xl: 1.5rem;
  --text-3xl: 1.875rem;
  --text-4xl: 2.25rem;
  --text-5xl: 3rem;

  --leading-none: 1;
  --leading-tight: 1.25;
  --leading-snug: 1.375;
  --leading-normal: 1.5;
  --leading-relaxed: 1.625;
  --leading-loose: 2;

  --font-normal: 400;
  --font-medium: 500;
  --font-semibold: 600;
  --font-bold: 700;

  /* ---- Border Radius ---- */
  --radius-none: 0;
  --radius-sm: 0.125rem;
  --radius-md: 0.375rem;
  --radius-lg: 0.5rem;
  --radius-xl: 0.75rem;
  --radius-2xl: 1rem;
  --radius-3xl: 1.5rem;
  --radius-full: 9999rem;

  /* ---- Shadows ---- */
  --shadow-xs: 0 0.0625rem 0.125rem 0 rgba(0, 0, 0, 0.05);
  --shadow-sm: 0 0.0625rem 0.1875rem 0 rgba(0, 0, 0, 0.1), 0 0.0625rem 0.125rem -0.0625rem rgba(0, 0, 0, 0.1);
  --shadow-md: 0 0.25rem 0.375rem -0.0625rem rgba(0, 0, 0, 0.1), 0 0.125rem 0.25rem -0.125rem rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 0.625rem 0.9375rem -0.1875rem rgba(0, 0, 0, 0.1), 0 0.25rem 0.375rem -0.25rem rgba(0, 0, 0, 0.1);
  --shadow-xl: 0 1.25rem 1.5625rem -0.3125rem rgba(0, 0, 0, 0.1), 0 0.5rem 0.625rem -0.375rem rgba(0, 0, 0, 0.1);
  --shadow-2xl: 0 1.5625rem 3.125rem -0.75rem rgba(0, 0, 0, 0.25);
  --shadow-inner: inset 0 0.125rem 0.25rem 0 rgba(0, 0, 0, 0.05);

  /* ---- Transitions ---- */
  --transition-fast: 0.15s ease;
  --transition-base: 0.2s ease;
  --transition-slow: 0.3s ease;
  --transition-smooth: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-bounce: 0.5s cubic-bezier(0.68, -0.55, 0.265, 1.55);

  /* ---- Z-Index Scale ---- */
  --z-dropdown: 10;
  --z-sticky: 20;
  --z-fixed: 30;
  --z-modal-backdrop: 40;
  --z-modal: 50;
  --z-popover: 60;
  --z-tooltip: 70;
  --z-toast: 80;

  /* ---- Component Sizing ---- */
  --header-height: 4rem;
  --sidebar-width: 16rem;
  --sidebar-collapsed: 4.5rem;
  --container-max: 80rem;
  --container-2xl: 96rem;
  --modal-sm: 28rem;
  --modal-md: 42rem;
  --modal-lg: 56rem;
  --modal-xl: 72rem;
  --touch-target: 2.75rem;
  --input-height: 2.5rem;
  --btn-height-sm: 2rem;
  --btn-height-md: 2.5rem;
  --btn-height-lg: 3rem;
}

/* ============================================
   2. DARK MODE OVERRIDES
   ============================================ */
.dark {
  --bg-primary: #0F172A;
  --bg-secondary: #1E293B;
  --bg-tertiary: #334155;
  --bg-inverse: #F8FAFC;

  --text-primary: #F1F5F9;
  --text-secondary: #94A3B8;
  --text-tertiary: #64748B;
  --text-inverse: #0F172A;
  --text-link: #60A5FA;
  --text-link-hover: #93BBFD;

  --border-primary: #334155;
  --border-secondary: #475569;
  --border-focus: #60A5FA;

  --surface-hover: #1E293B;
  --surface-active: #334155;

  --overlay-bg: rgba(0, 0, 0, 0.6);
  --overlay-bg-heavy: rgba(0, 0, 0, 0.75);

  --shadow-xs: 0 0.0625rem 0.125rem 0 rgba(0, 0, 0, 0.2);
  --shadow-sm: 0 0.0625rem 0.1875rem 0 rgba(0, 0, 0, 0.3), 0 0.0625rem 0.125rem -0.0625rem rgba(0, 0, 0, 0.3);
  --shadow-md: 0 0.25rem 0.375rem -0.0625rem rgba(0, 0, 0, 0.3), 0 0.125rem 0.25rem -0.125rem rgba(0, 0, 0, 0.3);
  --shadow-lg: 0 0.625rem 0.9375rem -0.1875rem rgba(0, 0, 0, 0.3), 0 0.25rem 0.375rem -0.25rem rgba(0, 0, 0, 0.3);
  --shadow-xl: 0 1.25rem 1.5625rem -0.3125rem rgba(0, 0, 0, 0.3), 0 0.5rem 0.625rem -0.375rem rgba(0, 0, 0, 0.3);
  --shadow-2xl: 0 1.5625rem 3.125rem -0.75rem rgba(0, 0, 0, 0.5);
}

/* ============================================
   3. BASE / RESET
   ============================================ */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-size: 100%;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-sans);
  font-size: var(--text-base);
  line-height: var(--leading-normal);
  color: var(--text-primary);
  background-color: var(--bg-primary);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  transition: background-color var(--transition-slow), color var(--transition-slow);
}

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

img, svg {
  display: block;
  max-width: 100%;
  height: auto;
}

button, input, select, textarea {
  font-family: inherit;
  font-size: inherit;
  line-height: inherit;
  color: inherit;
}

button {
  cursor: pointer;
  border: none;
  background: none;
}

[hidden] {
  display: none !important;
}

/* ============================================
   4. SKIP LINK (Accessibility)
   ============================================ */
.skip-link {
  position: absolute;
  top: -10rem;
  left: var(--space-4);
  z-index: var(--z-tooltip);
  padding: var(--space-3) var(--space-6);
  background: var(--brand-600);
  color: #FFFFFF;
  border-radius: var(--radius-lg);
  font-weight: var(--font-semibold);
  font-size: var(--text-sm);
  transition: top var(--transition-fast);
}
.skip-link:focus {
  top: var(--space-4);
  outline: 0.125rem solid var(--brand-500);
  outline-offset: 0.125rem;
}

/* ============================================
   5. LAYOUT CONTAINERS
   ============================================ */
.layout-wrapper {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

.main-content {
  flex: 1;
  padding: var(--space-6) 0;
}

.container {
  width: 100%;
  max-width: var(--container-max);
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--space-4);
  padding-right: var(--space-4);
}

@media (min-width: 40rem) {
  .container {
    padding-left: var(--space-6);
    padding-right: var(--space-6);
  }
}

@media (min-width: 64rem) {
  .container {
    padding-left: var(--space-8);
    padding-right: var(--space-8);
  }
}

.container-2xl {
  max-width: var(--container-2xl);
}

/* Layout with sidebar */
.layout-with-sidebar {
  display: flex;
  gap: var(--space-6);
}

.layout-sidebar {
  width: var(--sidebar-width);
  flex-shrink: 0;
}

.layout-main {
  flex: 1;
  min-width: 0;
}

@media (max-width: 63.9375rem) {
  .layout-with-sidebar {
    flex-direction: column;
  }
  .layout-sidebar {
    width: 100%;
  }
}

/* ============================================
   6. HEADER / NAVIGATION
   ============================================ */
.site-header {
  position: sticky;
  top: 0;
  z-index: var(--z-sticky);
  height: var(--header-height);
  background-color: var(--bg-secondary);
  border-bottom: 0.0625rem solid var(--border-primary);
  transition: background-color var(--transition-slow), border-color var(--transition-slow);
  backdrop-filter: blur(0.75rem);
}

.header-inner {
  display: flex;
  align-items: center;
  gap: var(--space-4);
  height: 100%;
  max-width: var(--container-2xl);
  margin: 0 auto;
  padding: 0 var(--space-4);
}

@media (min-width: 40rem) {
  .header-inner {
    padding: 0 var(--space-6);
  }
}

@media (min-width: 64rem) {
  .header-inner {
    padding: 0 var(--space-8);
  }
}

.header-left {
  display: flex;
  align-items: center;
  gap: var(--space-4);
}

.header-logo {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  font-size: var(--text-lg);
  font-weight: var(--font-bold);
  color: var(--text-primary);
  text-decoration: none;
}

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

.header-logo-icon {
  width: 2rem;
  height: 2rem;
  background: linear-gradient(135deg, var(--brand-600), var(--brand-500));
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #FFFFFF;
  font-size: var(--text-sm);
}

.header-nav {
  display: none;
  align-items: center;
  justify-content: center;
  flex: 1;
  gap: var(--space-1);
}

@media (min-width: 48rem) {
  .header-nav {
    display: flex;
  }
}

.header-nav-link {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-2) var(--space-3);
  font-size: var(--text-sm);
  font-weight: var(--font-medium);
  color: var(--text-secondary);
  border-radius: var(--radius-lg);
  transition: all var(--transition-fast);
  text-decoration: none;
  white-space: nowrap;
}

.header-nav-link:hover {
  color: var(--text-primary);
  background-color: var(--surface-hover);
}

.header-nav-link.active {
  color: var(--brand-600);
  background-color: var(--brand-50);
}

.dark .header-nav-link.active {
  color: var(--brand-500);
  background-color: rgba(59, 130, 246, 0.1);
}

.header-right {
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

/* ============================================
   7. BUTTONS
   ============================================ */

/* --- Base Button --- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  font-weight: var(--font-medium);
  white-space: nowrap;
  border-radius: var(--radius-lg);
  transition: all var(--transition-fast);
  cursor: pointer;
  text-decoration: none;
  border: 0.0625rem solid transparent;
  position: relative;
  overflow: hidden;
}

.btn:focus-visible {
  outline: 0.125rem solid var(--border-focus);
  outline-offset: 0.125rem;
}

.btn:disabled,
.btn.disabled {
  opacity: 0.5;
  cursor: not-allowed;
  pointer-events: none;
}

/* Sizes */
.btn-sm {
  height: var(--btn-height-sm);
  padding: 0 var(--space-3);
  font-size: var(--text-sm);
}

.btn-md {
  height: var(--btn-height-md);
  padding: 0 var(--space-4);
  font-size: var(--text-sm);
}

.btn-lg {
  height: var(--btn-height-lg);
  padding: 0 var(--space-6);
  font-size: var(--text-base);
}

/* Variants */
.btn-primary {
  background-color: var(--brand-600);
  color: #FFFFFF;
  border-color: var(--brand-600);
}
.btn-primary:hover {
  background-color: var(--brand-700);
  border-color: var(--brand-700);
}
.btn-primary:active {
  background-color: var(--brand-800);
}

.btn-secondary {
  background-color: transparent;
  color: var(--text-primary);
  border-color: var(--border-primary);
}
.btn-secondary:hover {
  background-color: var(--surface-hover);
  border-color: var(--border-secondary);
}

.btn-ghost {
  background-color: transparent;
  color: var(--text-secondary);
}
.btn-ghost:hover {
  background-color: var(--surface-hover);
  color: var(--text-primary);
}

.btn-danger {
  background-color: var(--error-600);
  color: #FFFFFF;
  border-color: var(--error-600);
}
.btn-danger:hover {
  background-color: var(--error-700);
  border-color: var(--error-700);
}

.btn-success {
  background-color: var(--success-600);
  color: #FFFFFF;
  border-color: var(--success-600);
}
.btn-success:hover {
  background-color: var(--success-700);
  border-color: var(--success-700);
}

.btn-warning {
  background-color: var(--warning-600);
  color: #FFFFFF;
  border-color: var(--warning-600);
}
.btn-warning:hover {
  background-color: var(--warning-700);
  border-color: var(--warning-700);
}

/* Icon-only button */
.btn-icon {
  width: var(--btn-height-md);
  height: var(--btn-height-md);
  padding: 0;
  border-radius: var(--radius-lg);
}
.btn-icon.btn-sm {
  width: var(--btn-height-sm);
  height: var(--btn-height-sm);
}
.btn-icon.btn-lg {
  width: var(--btn-height-lg);
  height: var(--btn-height-lg);
}

/* Loading state */
.btn-loading {
  color: transparent !important;
  pointer-events: none;
}
.btn-loading::after {
  content: '';
  position: absolute;
  width: 1.125rem;
  height: 1.125rem;
  border: 0.125rem solid rgba(255, 255, 255, 0.3);
  border-top-color: #FFFFFF;
  border-radius: var(--radius-full);
  animation: spin 0.6s linear infinite;
}
.btn-secondary.btn-loading::after {
  border-color: rgba(0, 0, 0, 0.15);
  border-top-color: var(--text-primary);
}

/* ============================================
   8. FORM ELEMENTS
   ============================================ */
.form-group {
  margin-bottom: var(--space-5);
}

.form-label {
  display: block;
  font-size: var(--text-sm);
  font-weight: var(--font-medium);
  color: var(--text-primary);
  margin-bottom: var(--space-1-5);
}

.form-label-required::after {
  content: ' *';
  color: var(--error-500);
}

.form-input {
  display: block;
  width: 100%;
  height: var(--input-height);
  padding: 0 var(--space-3);
  font-size: var(--text-sm);
  color: var(--text-primary);
  background-color: var(--bg-primary);
  border: 0.0625rem solid var(--border-primary);
  border-radius: var(--radius-lg);
  transition: all var(--transition-fast);
  appearance: none;
}

.form-input::placeholder {
  color: var(--text-tertiary);
}

.form-input:hover {
  border-color: var(--border-secondary);
}

.form-input:focus {
  outline: none;
  border-color: var(--border-focus);
  box-shadow: 0 0 0 0.1875rem rgba(59, 130, 246, 0.15);
}

.form-input.is-error {
  border-color: var(--error-500);
}
.form-input.is-error:focus {
  box-shadow: 0 0 0 0.1875rem rgba(239, 68, 68, 0.15);
}

.form-input.is-success {
  border-color: var(--success-500);
}

.form-input:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  background-color: var(--bg-tertiary);
}

.form-textarea {
  height: auto;
  min-height: 5rem;
  padding: var(--space-3);
  resize: vertical;
}

.form-select {
  padding-right: var(--space-10);
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 20 20' fill='%236B7280'%3E%3Cpath fill-rule='evenodd' d='M5.23 7.21a.75.75 0 011.06.02L10 11.168l3.71-3.938a.75.75 0 111.08 1.04l-4.25 4.5a.75.75 0 01-1.08 0l-4.25-4.5a.75.75 0 01.02-1.06z'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right var(--space-3) center;
  background-size: 1.25rem;
}

.form-helper {
  display: block;
  margin-top: var(--space-1-5);
  font-size: var(--text-xs);
  color: var(--text-tertiary);
}

.form-error {
  display: flex;
  align-items: center;
  gap: var(--space-1);
  margin-top: var(--space-1-5);
  font-size: var(--text-xs);
  color: var(--error-500);
  animation: slideDown 0.2s ease;
}

.form-error i {
  font-size: var(--text-xs);
}

/* Checkbox & Radio */
.form-check {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  cursor: pointer;
}

.form-check-input {
  width: 1.125rem;
  height: 1.125rem;
  border: 0.0625rem solid var(--border-secondary);
  border-radius: var(--radius-sm);
  appearance: none;
  cursor: pointer;
  transition: all var(--transition-fast);
  flex-shrink: 0;
}

.form-check-input[type="radio"] {
  border-radius: var(--radius-full);
}

.form-check-input:checked {
  background-color: var(--brand-600);
  border-color: var(--brand-600);
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 20 20' fill='white'%3E%3Cpath fill-rule='evenodd' d='M16.707 5.293a1 1 0 010 1.414l-8 8a1 1 0 01-1.414 0l-4-4a1 1 0 011.414-1.414L8 12.586l7.293-7.293a1 1 0 011.414 0z'/%3E%3C/svg%3E");
  background-size: 0.75rem;
  background-position: center;
  background-repeat: no-repeat;
}

.form-check-input[type="radio"]:checked {
  background-image: none;
  box-shadow: inset 0 0 0 0.1875rem var(--bg-primary);
}

.form-check-label {
  font-size: var(--text-sm);
  color: var(--text-primary);
  cursor: pointer;
  user-select: none;
}

/* ============================================
   9. CARDS
   ============================================ */
.card {
  background-color: var(--bg-secondary);
  border: 0.0625rem solid var(--border-primary);
  border-radius: var(--radius-xl);
  transition: all var(--transition-smooth);
}

.card-hover:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-0.0625rem);
  border-color: var(--border-secondary);
}

.card-body {
  padding: var(--space-5);
}

@media (min-width: 40rem) {
  .card-body {
    padding: var(--space-6);
  }
}

.card-header {
  padding: var(--space-4) var(--space-5);
  border-bottom: 0.0625rem solid var(--border-primary);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

@media (min-width: 40rem) {
  .card-header {
    padding: var(--space-4) var(--space-6);
  }
}

.card-footer {
  padding: var(--space-4) var(--space-5);
  border-top: 0.0625rem solid var(--border-primary);
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: var(--space-3);
}

@media (min-width: 40rem) {
  .card-footer {
    padding: var(--space-4) var(--space-6);
  }
}

/* Stat card */
.stat-card {
  background-color: var(--bg-secondary);
  border: 0.0625rem solid var(--border-primary);
  border-radius: var(--radius-xl);
  padding: var(--space-5);
  transition: all var(--transition-smooth);
}

.stat-card:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-0.125rem);
}

.stat-card-icon {
  width: 2.75rem;
  height: 2.75rem;
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--text-lg);
}

.stat-card-value {
  font-size: var(--text-2xl);
  font-weight: var(--font-bold);
  color: var(--text-primary);
  margin-top: var(--space-3);
}

.stat-card-label {
  font-size: var(--text-sm);
  color: var(--text-secondary);
  margin-top: var(--space-1);
}

/* ============================================
   10. BADGES / TAGS
   ============================================ */
.badge {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  padding: var(--space-0-5) var(--space-2);
  font-size: var(--text-xs);
  font-weight: var(--font-medium);
  border-radius: var(--radius-md);
  white-space: nowrap;
  line-height: var(--leading-normal);
}

.badge-primary {
  background-color: var(--brand-100);
  color: var(--brand-700);
}
.dark .badge-primary {
  background-color: rgba(59, 130, 246, 0.15);
  color: var(--brand-500);
}

.badge-success {
  background-color: var(--success-100);
  color: var(--success-700);
}
.dark .badge-success {
  background-color: rgba(34, 197, 94, 0.15);
  color: var(--success-500);
}

.badge-warning {
  background-color: var(--warning-100);
  color: var(--warning-700);
}
.dark .badge-warning {
  background-color: rgba(245, 158, 11, 0.15);
  color: var(--warning-500);
}

.badge-error {
  background-color: var(--error-100);
  color: var(--error-700);
}
.dark .badge-error {
  background-color: rgba(239, 68, 68, 0.15);
  color: var(--error-500);
}

.badge-gray {
  background-color: var(--bg-tertiary);
  color: var(--text-secondary);
}
.dark .badge-gray {
  background-color: rgba(100, 116, 139, 0.2);
  color: var(--text-tertiary);
}

/* ============================================
   11. MODALS
   Not achievable with Tailwind: max-height calc,
   custom scrollbar, fixed header/footer in flex column
   ============================================ */
.modal-backdrop {
  position: fixed;
  inset: 0;
  background-color: var(--overlay-bg);
  z-index: var(--z-modal-backdrop);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-4);
  opacity: 0;
  visibility: hidden;
  transition: opacity var(--transition-slow), visibility var(--transition-slow);
}

.modal-backdrop.is-open {
  opacity: 1;
  visibility: visible;
}

.modal {
  background-color: var(--bg-secondary);
  border: 0.0625rem solid var(--border-primary);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-2xl);
  width: 100%;
  max-height: 85vh;
  display: flex;
  flex-direction: column;
  transform: scale(0.95) translateY(0.625rem);
  transition: transform var(--transition-smooth);
  overflow: hidden;
}

.modal-backdrop.is-open .modal {
  transform: scale(1) translateY(0);
}

.modal-sm { max-width: var(--modal-sm); }
.modal-md { max-width: var(--modal-md); }
.modal-lg { max-width: var(--modal-lg); }
.modal-xl { max-width: var(--modal-xl); }

.modal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-4) var(--space-6);
  border-bottom: 0.0625rem solid var(--border-primary);
  flex-shrink: 0;
}

.modal-title {
  font-size: var(--text-lg);
  font-weight: var(--font-semibold);
  color: var(--text-primary);
}

.modal-close {
  width: 2rem;
  height: 2rem;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-lg);
  color: var(--text-tertiary);
  transition: all var(--transition-fast);
}
.modal-close:hover {
  background-color: var(--surface-hover);
  color: var(--text-primary);
}

.modal-body {
  flex: 1;
  overflow-y: auto;
  padding: var(--space-6);
  /* max-height accounts for header (~3.5rem) + footer (~4rem) */
  max-height: calc(85vh - 7.5rem);
}

.modal-footer {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: var(--space-3);
  padding: var(--space-4) var(--space-6);
  border-top: 0.0625rem solid var(--border-primary);
  flex-shrink: 0;
}

/* ============================================
   12. CUSTOM SCROLLBAR
   Not achievable with Tailwind
   ============================================ */
.modal-body::-webkit-scrollbar,
.custom-scroll::-webkit-scrollbar {
  width: 0.375rem;
}

.modal-body::-webkit-scrollbar-track,
.custom-scroll::-webkit-scrollbar-track {
  background: var(--bg-tertiary);
  border-radius: var(--radius-full);
}

.modal-body::-webkit-scrollbar-thumb,
.custom-scroll::-webkit-scrollbar-thumb {
  background-color: var(--border-secondary);
  border-radius: var(--radius-full);
  transition: background-color var(--transition-fast);
}

.modal-body::-webkit-scrollbar-thumb:hover,
.custom-scroll::-webkit-scrollbar-thumb:hover {
  background-color: var(--text-tertiary);
}

/* Firefox scrollbar */
.modal-body,
.custom-scroll {
  scrollbar-width: thin;
  scrollbar-color: var(--border-secondary) var(--bg-tertiary);
}

/* ============================================
   13. TOAST / NOTIFICATION SYSTEM
   Not achievable with Tailwind: stacking, 
   slide-in/out animations, auto-dismiss
   ============================================ */
.toast-container {
  position: fixed;
  top: var(--space-4);
  right: var(--space-4);
  z-index: var(--z-toast);
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
  max-width: 24rem;
  width: 100%;
  pointer-events: none;
}

.toast {
  display: flex;
  align-items: flex-start;
  gap: var(--space-3);
  padding: var(--space-4);
  background-color: var(--bg-secondary);
  border: 0.0625rem solid var(--border-primary);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-lg);
  pointer-events: auto;
  animation: toastSlideIn 0.3s ease forwards;
  transition: all var(--transition-smooth);
}

.toast.is-dismissing {
  animation: toastSlideOut 0.25s ease forwards;
}

.toast-icon {
  width: 1.5rem;
  height: 1.5rem;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--text-base);
  flex-shrink: 0;
  margin-top: 0.0625rem;
}

.toast-content {
  flex: 1;
  min-width: 0;
}

.toast-title {
  font-size: var(--text-sm);
  font-weight: var(--font-semibold);
  color: var(--text-primary);
}

.toast-message {
  font-size: var(--text-sm);
  color: var(--text-secondary);
  margin-top: var(--space-0-5);
}

.toast-close {
  width: 1.5rem;
  height: 1.5rem;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-tertiary);
  border-radius: var(--radius-md);
  flex-shrink: 0;
  transition: all var(--transition-fast);
}
.toast-close:hover {
  background-color: var(--surface-hover);
  color: var(--text-primary);
}

/* Toast variants */
.toast-success { border-left: 0.1875rem solid var(--success-500); }
.toast-success .toast-icon { color: var(--success-500); }

.toast-error { border-left: 0.1875rem solid var(--error-500); }
.toast-error .toast-icon { color: var(--error-500); }

.toast-warning { border-left: 0.1875rem solid var(--warning-500); }
.toast-warning .toast-icon { color: var(--warning-500); }

.toast-info { border-left: 0.1875rem solid var(--info-500); }
.toast-info .toast-icon { color: var(--info-500); }

/* Progress bar on toast */
.toast-progress {
  position: absolute;
  bottom: 0;
  left: 0;
  height: 0.1875rem;
  background-color: var(--brand-500);
  border-radius: 0 0 var(--radius-xl) var(--radius-xl);
  animation: toastProgress linear forwards;
}

/* ============================================
   14. DRAG & DROP
   Complex interaction states not achievable with Tailwind
   ============================================ */
.draggable {
  cursor: grab;
  touch-action: none;
  transition: all var(--transition-smooth);
}

.draggable:active {
  cursor: grabbing;
}

.draggable.is-dragging {
  opacity: 0.4;
  transform: scale(0.97);
}

.drag-handle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 1.5rem;
  color: var(--text-tertiary);
  cursor: grab;
  flex-shrink: 0;
  transition: color var(--transition-fast);
}

.drag-handle:hover {
  color: var(--text-secondary);
}

.drag-handle:active {
  cursor: grabbing;
}

.drop-zone {
  min-height: 5rem;
  border: 0.125rem dashed var(--border-primary);
  border-radius: var(--radius-xl);
  transition: all var(--transition-smooth);
  display: flex;
  align-items: center;
  justify-content: center;
}

.drop-zone.drag-over {
  border-color: var(--brand-500);
  background-color: rgba(59, 130, 246, 0.06);
  transform: scale(1.01);
}

.dark .drop-zone.drag-over {
  background-color: rgba(59, 130, 246, 0.08);
}

/* Role drop zones — drag-drop user cards */
.role-dropzone {
  min-height: 8rem;
  border: 0.125rem dashed var(--border-primary);
  border-radius: var(--radius-lg);
  padding: var(--space-3);
  transition: all var(--transition-smooth);
}

.role-dropzone.drag-over {
  border-color: var(--brand-500);
  background-color: rgba(59, 130, 246, 0.06);
  transform: scale(1.01);
}

.user-card {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: var(--space-3);
  background-color: var(--bg-primary);
  border: 0.0625rem solid var(--border-primary);
  border-radius: var(--radius-lg);
  cursor: grab;
  transition: all var(--transition-smooth);
}

.user-card:hover {
  transform: translateY(-0.125rem);
  box-shadow: var(--shadow-md);
}

.user-card.is-dragging {
  opacity: 0.5;
  transform: scale(0.95);
}

/* ============================================
   15. PERMISSION MATRIX
   CSS Grid layout not achievable with Tailwind alone
   ============================================ */
.permission-matrix {
  display: grid;
  grid-template-columns: 12rem repeat(4, 1fr);
  gap: 0.0625rem;
  background-color: var(--border-primary);
  border-radius: var(--radius-lg);
  overflow: hidden;
}

@media (max-width: 47.9375rem) {
  .permission-matrix {
    grid-template-columns: 8rem repeat(4, 1fr);
    font-size: var(--text-xs);
  }
}

.permission-cell {
  background-color: var(--bg-secondary);
  padding: var(--space-3);
  display: flex;
  align-items: center;
}

.permission-cell.is-header {
  font-weight: var(--font-semibold);
  font-size: var(--text-sm);
}

.permission-cell.is-center {
  justify-content: center;
}

/* ============================================
   16. FILE UPLOAD DROP ZONE
   Complex hover/active states + animations
   ============================================ */
.upload-zone {
  position: relative;
  border: 0.125rem dashed var(--border-secondary);
  border-radius: var(--radius-xl);
  padding: var(--space-8);
  text-align: center;
  cursor: pointer;
  transition: all var(--transition-smooth);
  background-color: var(--bg-primary);
}

.upload-zone:hover {
  border-color: var(--brand-500);
  background-color: rgba(59, 130, 246, 0.03);
}

.upload-zone.drag-over {
  border-color: var(--brand-500);
  background-color: rgba(59, 130, 246, 0.08);
  transform: scale(1.01);
}

.upload-zone-icon {
  font-size: var(--text-5xl);
  color: var(--text-tertiary);
  margin-bottom: var(--space-4);
  transition: color var(--transition-fast);
}

.upload-zone:hover .upload-zone-icon {
  color: var(--brand-500);
}

/* ============================================
   17. TABLE STYLES
   ============================================ */
.data-table {
  width: 100%;
  border-collapse: collapse;
}

.data-table th {
  padding: var(--space-3) var(--space-4);
  font-size: var(--text-xs);
  font-weight: var(--font-medium);
  color: var(--text-tertiary);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  text-align: left;
  background-color: var(--bg-tertiary);
  border-bottom: 0.0625rem solid var(--border-primary);
  white-space: nowrap;
}

.data-table td {
  padding: var(--space-3) var(--space-4);
  font-size: var(--text-sm);
  color: var(--text-primary);
  border-bottom: 0.0625rem solid var(--border-primary);
  vertical-align: middle;
}

.data-table tbody tr {
  transition: background-color var(--transition-fast);
}

.data-table tbody tr:hover {
  background-color: var(--surface-hover);
}

.data-table tbody tr.is-selected {
  background-color: rgba(59, 130, 246, 0.06);
}

/* ============================================
   18. BULK ACTION BAR
   Fixed bottom bar with slide-up animation
   ============================================ */
.bulk-action-bar {
  position: fixed;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%) translateY(100%);
  z-index: var(--z-fixed);
  background-color: var(--bg-secondary);
  border: 0.0625rem solid var(--border-primary);
  border-bottom: none;
  border-radius: var(--radius-xl) var(--radius-xl) 0 0;
  box-shadow: var(--shadow-2xl);
  padding: var(--space-3) var(--space-6);
  display: flex;
  align-items: center;
  gap: var(--space-4);
  transition: transform var(--transition-smooth);
  white-space: nowrap;
}

.bulk-action-bar.is-visible {
  transform: translateX(-50%) translateY(0);
}

/* ============================================
   19. EMPTY STATES
   ============================================ */
.empty-state {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: var(--space-12) var(--space-4);
  text-align: center;
}

.empty-state-icon {
  font-size: 3.75rem;
  color: var(--text-tertiary);
  margin-bottom: var(--space-4);
  opacity: 0.5;
}

.empty-state-title {
  font-size: var(--text-lg);
  font-weight: var(--font-semibold);
  color: var(--text-primary);
  margin-bottom: var(--space-2);
}

.empty-state-desc {
  font-size: var(--text-sm);
  color: var(--text-secondary);
  max-width: 24rem;
  margin-bottom: var(--space-6);
}

/* ============================================
   20. TREE / HIERARCHY NODES
   ============================================ */
.tree-node {
  padding-left: var(--space-6);
  position: relative;
}

.tree-node::before {
  content: '';
  position: absolute;
  left: 1rem;
  top: 0;
  bottom: 0;
  width: 0.0625rem;
  background-color: var(--border-primary);
}

.tree-node-item {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-2) var(--space-3);
  border-radius: var(--radius-lg);
  transition: background-color var(--transition-fast);
  cursor: pointer;
  position: relative;
}

.tree-node-item:hover {
  background-color: var(--surface-hover);
}

.tree-node-item.is-selected {
  background-color: rgba(59, 130, 246, 0.1);
  color: var(--brand-600);
}

.dark .tree-node-item.is-selected {
  color: var(--brand-500);
}

.tree-toggle {
  width: 1.25rem;
  height: 1.25rem;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--text-xs);
  color: var(--text-tertiary);
  border-radius: var(--radius-sm);
  transition: all var(--transition-fast);
  flex-shrink: 0;
}

.tree-toggle:hover {
  background-color: var(--surface-hover);
  color: var(--text-primary);
}

.tree-toggle.is-expanded {
  transform: rotate(90deg);
}

/* ============================================
   21. LOADING / SKELETON
   ============================================ */
.spinner {
  display: inline-block;
  width: 1.25rem;
  height: 1.25rem;
  border: 0.125rem solid var(--border-secondary);
  border-top-color: var(--brand-600);
  border-radius: var(--radius-full);
  animation: spin 0.6s linear infinite;
}

.spinner-lg {
  width: 2.5rem;
  height: 2.5rem;
  border-width: 0.1875rem;
}

.skeleton {
  background: linear-gradient(
    90deg,
    var(--bg-tertiary) 25%,
    var(--border-primary) 50%,
    var(--bg-tertiary) 75%
  );
  background-size: 200% 100%;
  animation: shimmer 1.5s ease-in-out infinite;
  border-radius: var(--radius-md);
}

.skeleton-text {
  height: 0.875rem;
  margin-bottom: var(--space-2);
  border-radius: var(--radius-md);
}

.skeleton-text:last-child {
  width: 60%;
}

.skeleton-circle {
  border-radius: var(--radius-full);
}

.skeleton-card {
  height: 10rem;
  border-radius: var(--radius-xl);
}

/* Full-page loader overlay */
.page-loader {
  position: fixed;
  inset: 0;
  z-index: var(--z-modal);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: var(--space-4);
  background-color: var(--overlay-bg);
}

.page-loader-text {
  font-size: var(--text-sm);
  color: var(--text-inverse);
  font-weight: var(--font-medium);
}

/* ============================================
   22. FOOTER
   ============================================ */
.site-footer {
  background-color: var(--bg-secondary);
  border-top: 0.0625rem solid var(--border-primary);
  padding: var(--space-8) 0;
  margin-top: auto;
  transition: background-color var(--transition-slow), border-color var(--transition-slow);
}

.footer-inner {
  max-width: var(--container-2xl);
  margin: 0 auto;
  padding: 0 var(--space-4);
  display: flex;
  flex-direction: column;
  gap: var(--space-6);
}

@media (min-width: 40rem) {
  .footer-inner {
    padding: 0 var(--space-6);
  }
}

@media (min-width: 48rem) {
  .footer-inner {
    flex-direction: row;
    justify-content: space-between;
    align-items: flex-start;
  }
}

@media (min-width: 64rem) {
  .footer-inner {
    padding: 0 var(--space-8);
  }
}

.footer-section {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.footer-title {
  font-size: var(--text-sm);
  font-weight: var(--font-semibold);
  color: var(--text-primary);
  margin-bottom: var(--space-1);
}

.footer-link {
  font-size: var(--text-sm);
  color: var(--text-secondary);
  text-decoration: none;
  transition: color var(--transition-fast);
}

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

.footer-bottom {
  padding-top: var(--space-6);
  border-top: 0.0625rem solid var(--border-primary);
  font-size: var(--text-xs);
  color: var(--text-tertiary);
  text-align: center;
}

@media (min-width: 48rem) {
  .footer-bottom {
    text-align: left;
  }
}

/* ============================================
   23. MOBILE MENU
   Slide-in from left
   ============================================ */
.mobile-menu-backdrop {
  position: fixed;
  inset: 0;
  z-index: var(--z-modal-backdrop);
  background-color: var(--overlay-bg);
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition-slow);
}

.mobile-menu-backdrop.is-open {
  opacity: 1;
  visibility: visible;
}

.mobile-menu {
  position: fixed;
  top: 0;
  left: 0;
  bottom: 0;
  z-index: var(--z-modal);
  width: 18rem;
  max-width: 80vw;
  background-color: var(--bg-secondary);
  border-right: 0.0625rem solid var(--border-primary);
  transform: translateX(-100%);
  transition: transform var(--transition-smooth);
  display: flex;
  flex-direction: column;
  overflow-y: auto;
}

.mobile-menu-backdrop.is-open .mobile-menu {
  transform: translateX(0);
}

.mobile-menu-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-4) var(--space-5);
  border-bottom: 0.0625rem solid var(--border-primary);
}

.mobile-menu-nav {
  padding: var(--space-4);
  display: flex;
  flex-direction: column;
  gap: var(--space-1);
}

.mobile-menu-link {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: var(--space-3) var(--space-4);
  font-size: var(--text-sm);
  font-weight: var(--font-medium);
  color: var(--text-secondary);
  border-radius: var(--radius-lg);
  text-decoration: none;
  transition: all var(--transition-fast);
}

.mobile-menu-link:hover {
  color: var(--text-primary);
  background-color: var(--surface-hover);
}

.mobile-menu-link.active {
  color: var(--brand-600);
  background-color: var(--brand-50);
}

.dark .mobile-menu-link.active {
  color: var(--brand-500);
  background-color: rgba(59, 130, 246, 0.1);
}

.mobile-menu-link i {
  width: 1.25rem;
  text-align: center;
}

/* ============================================
   24. PAGINATION
   ============================================ */
.pagination {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-1);
}

.pagination-btn {
  min-width: 2.25rem;
  height: 2.25rem;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--text-sm);
  font-weight: var(--font-medium);
  color: var(--text-secondary);
  border-radius: var(--radius-lg);
  transition: all var(--transition-fast);
}

.pagination-btn:hover {
  background-color: var(--surface-hover);
  color: var(--text-primary);
}

.pagination-btn.active {
  background-color: var(--brand-600);
  color: #FFFFFF;
}

.pagination-btn:disabled {
  opacity: 0.4;
  cursor: not-allowed;
}

/* ============================================
   25. BREADCRUMBS
   ============================================ */
.breadcrumbs {
  display: flex;
  align-items: center;
  gap: var(--space-1);
  font-size: var(--text-sm);
  color: var(--text-secondary);
  flex-wrap: wrap;
}

.breadcrumb-separator {
  color: var(--text-tertiary);
  font-size: var(--text-xs);
}

.breadcrumb-link {
  color: var(--text-secondary);
  text-decoration: none;
  transition: color var(--transition-fast);
}

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

.breadcrumb-current {
  color: var(--text-primary);
  font-weight: var(--font-medium);
}

/* ============================================
   26. TABS
   ============================================ */
.tabs {
  display: flex;
  gap: var(--space-6);
  border-bottom: 0.0625rem solid var(--border-primary);
  overflow-x: auto;
  scrollbar-width: none;
}

.tabs::-webkit-scrollbar {
  display: none;
}

.tab {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-1);
  font-size: var(--text-sm);
  font-weight: var(--font-medium);
  color: var(--text-secondary);
  border-bottom: 0.125rem solid transparent;
  white-space: nowrap;
  transition: all var(--transition-fast);
  cursor: pointer;
}

.tab:hover {
  color: var(--text-primary);
  border-color: var(--border-secondary);
}

.tab.active {
  color: var(--brand-600);
  border-color: var(--brand-600);
}

.dark .tab.active {
  color: var(--brand-500);
  border-color: var(--brand-500);
}

/* ============================================
   27. AVATAR
   ============================================ */
.avatar {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-full);
  background-color: var(--brand-100);
  color: var(--brand-700);
  font-weight: var(--font-semibold);
  flex-shrink: 0;
  overflow: hidden;
}

.dark .avatar {
  background-color: rgba(59, 130, 246, 0.2);
  color: var(--brand-500);
}

.avatar-sm {
  width: 2rem;
  height: 2rem;
  font-size: var(--text-xs);
}

.avatar-md {
  width: 2.5rem;
  height: 2.5rem;
  font-size: var(--text-sm);
}

.avatar-lg {
  width: 3rem;
  height: 3rem;
  font-size: var(--text-base);
}

.avatar img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

/* ============================================
   28. FILTER CHIPS
   ============================================ */
.filter-chip {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1-5);
  padding: var(--space-1-5) var(--space-3);
  font-size: var(--text-sm);
  font-weight: var(--font-medium);
  border-radius: var(--radius-full);
  border: 0.0625rem solid var(--border-primary);
  background-color: var(--bg-primary);
  color: var(--text-secondary);
  cursor: pointer;
  transition: all var(--transition-fast);
  white-space: nowrap;
}

.filter-chip:hover {
  background-color: var(--surface-hover);
  border-color: var(--border-secondary);
}

.filter-chip.active {
  background-color: var(--brand-600);
  color: #FFFFFF;
  border-color: var(--brand-600);
}

/* ============================================
   29. PROGRESS BAR
   ============================================ */
.progress-bar {
  width: 100%;
  height: 0.5rem;
  background-color: var(--bg-tertiary);
  border-radius: var(--radius-full);
  overflow: hidden;
}

.progress-fill {
  height: 100%;
  background-color: var(--brand-600);
  border-radius: var(--radius-full);
  transition: width var(--transition-smooth);
}

.progress-fill-success { background-color: var(--success-500); }
.progress-fill-warning { background-color: var(--warning-500); }
.progress-fill-error { background-color: var(--error-500); }

/* ============================================
   30. KEYFRAME ANIMATIONS
   ============================================ */
@keyframes spin {
  to { transform: rotate(360deg); }
}

@keyframes shimmer {
  0% { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}

@keyframes toastSlideIn {
  from {
    opacity: 0;
    transform: translateX(2rem);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

@keyframes toastSlideOut {
  from {
    opacity: 1;
    transform: translateX(0);
    max-height: 10rem;
    margin-bottom: var(--space-3);
  }
  to {
    opacity: 0;
    transform: translateX(2rem);
    max-height: 0;
    margin-bottom: 0;
    padding-top: 0;
    padding-bottom: 0;
  }
}

@keyframes slideDown {
  from {
    opacity: 0;
    transform: translateY(-0.25rem);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes slideUp {
  from {
    opacity: 0;
    transform: translateY(0.5rem);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

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

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

@keyframes scaleIn {
  from {
    opacity: 0;
    transform: scale(0.9);
  }
  to {
    opacity: 1;
    transform: scale(1);
  }
}

@keyframes badgePulse {
  0%, 100% { transform: scale(1); }
  50% { transform: scale(1.05); }
}

@keyframes toastProgress {
  from { width: 100%; }
  to { width: 0%; }
}

@keyframes bounce {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-0.25rem); }
}

/* ============================================
   31. UTILITY CLASSES
   Supplements for when Tailwind classes are insufficient
   ============================================ */
.visually-hidden {
  position: absolute;
  width: 0.0625rem;
  height: 0.0625rem;
  padding: 0;
  margin: -0.0625rem;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.truncate-2 {
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.truncate-3 {
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.no-scrollbar::-webkit-scrollbar {
  display: none;
}
.no-scrollbar {
  scrollbar-width: none;
}

/* Focus ring for keyboard navigation */
.focus-ring:focus-visible {
  outline: 0.125rem solid var(--border-focus);
  outline-offset: 0.125rem;
}

/* Animated icon for collection folder */
.collection-icon-animated {
  transition: transform var(--transition-smooth);
}

.collection-icon-animated:hover {
  transform: rotate(-5deg) scale(1.1);
}

/* Staggered animation delays for list items */
.stagger-1 { animation-delay: 0.05s; }
.stagger-2 { animation-delay: 0.1s; }
.stagger-3 { animation-delay: 0.15s; }
.stagger-4 { animation-delay: 0.2s; }
.stagger-5 { animation-delay: 0.25s; }
.stagger-6 { animation-delay: 0.3s; }
.stagger-7 { animation-delay: 0.35s; }
.stagger-8 { animation-delay: 0.4s; }

/* ============================================
   32. PRINT STYLES
   ============================================ */
@media print {
  .site-header,
  .site-footer,
  .mobile-menu-backdrop,
  .toast-container,
  .bulk-action-bar,
  .btn-icon,
  .skip-link {
    display: none !important;
  }

  body {
    background: #FFFFFF;
    color: #000000;
  }

  .card {
    border: 0.0625rem solid #E5E7EB;
    box-shadow: none;
  }
}