/* ============================================
   Aula STEAM - Estilos Compartidos
   ============================================ */

/* === VARIABLES CSS === */
:root {
  /* Colores principales */
  --color-primary: #1e3a5f;
  --color-primary-dark: #152a45;
  --color-primary-light: #2d5a87;
  --color-secondary: #2d5a87;

  /* Colores de estado */
  --color-success: #10b981;
  --color-success-light: #d1fae5;
  --color-danger: #ef4444;
  --color-danger-light: #fee2e2;
  --color-warning: #f59e0b;
  --color-warning-light: #fef3c7;
  --color-info: #3b82f6;
  --color-info-light: #dbeafe;

  /* Colores neutros */
  --color-white: #ffffff;
  --color-light: #f3f4f6;
  --color-gray-100: #f3f4f6;
  --color-gray-200: #e5e7eb;
  --color-gray-300: #d1d5db;
  --color-gray-400: #9ca3af;
  --color-gray-500: #6b7280;
  --color-gray-600: #4b5563;
  --color-gray-700: #374151;
  --color-gray-800: #1f2937;
  --color-dark: #1f2937;
  --color-black: #111827;

  /* Tipografía */
  --font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
  --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: 2rem;
  --font-size-4xl: 2.5rem;

  /* Espaciado */
  --spacing-1: 0.25rem;
  --spacing-2: 0.5rem;
  --spacing-3: 0.75rem;
  --spacing-4: 1rem;
  --spacing-5: 1.5rem;
  --spacing-6: 2rem;
  --spacing-8: 3rem;

  /* Bordes */
  --border-radius: 8px;
  --border-radius-sm: 4px;
  --border-radius-lg: 12px;
  --border-radius-full: 9999px;

  /* Sombras */
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
  --shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
  --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.1);
  --shadow-xl: 0 20px 25px rgba(0, 0, 0, 0.15);

  /* Transiciones */
  --transition-fast: 150ms ease;
  --transition-base: 200ms ease;
  --transition-slow: 300ms ease;

  /* Z-index */
  --z-dropdown: 100;
  --z-sticky: 200;
  --z-modal-backdrop: 900;
  --z-modal: 1000;
  --z-toast: 1100;
}

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

html {
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-family);
  font-size: var(--font-size-base);
  line-height: 1.6;
  color: var(--color-dark);
  background-color: var(--color-light);
  min-height: 100vh;
}

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

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

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

a:hover {
  text-decoration: underline;
}

ul,
ol {
  list-style: none;
}

table {
  border-collapse: collapse;
  width: 100%;
}

/* === TIPOGRAFÍA === */
h1, .h1 {
  font-size: var(--font-size-4xl);
  font-weight: 700;
  line-height: 1.2;
  margin-bottom: var(--spacing-4);
}

h2, .h2 {
  font-size: var(--font-size-3xl);
  font-weight: 600;
  line-height: 1.3;
  margin-bottom: var(--spacing-3);
}

h3, .h3 {
  font-size: var(--font-size-2xl);
  font-weight: 600;
  line-height: 1.4;
  margin-bottom: var(--spacing-3);
}

h4, .h4 {
  font-size: var(--font-size-xl);
  font-weight: 500;
  line-height: 1.4;
  margin-bottom: var(--spacing-2);
}

h5, .h5 {
  font-size: var(--font-size-lg);
  font-weight: 500;
  line-height: 1.5;
  margin-bottom: var(--spacing-2);
}

h6, .h6 {
  font-size: var(--font-size-base);
  font-weight: 500;
  line-height: 1.5;
  margin-bottom: var(--spacing-2);
}

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

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

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

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

.text-muted {
  color: var(--color-gray-500);
}

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

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

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

.font-bold {
  font-weight: 700;
}

.font-semibold {
  font-weight: 600;
}

.font-medium {
  font-weight: 500;
}

.font-normal {
  font-weight: 400;
}

/* === BOTONES === */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-2);
  padding: var(--spacing-2) var(--spacing-4);
  font-size: var(--font-size-base);
  font-weight: 500;
  line-height: 1.5;
  border: 1px solid transparent;
  border-radius: var(--border-radius);
  cursor: pointer;
  transition: all var(--transition-base);
  text-decoration: none;
  white-space: nowrap;
}

.btn:hover {
  text-decoration: none;
}

.btn:focus {
  outline: none;
  box-shadow: 0 0 0 3px rgba(30, 58, 95, 0.3);
}

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

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

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

.btn-secondary {
  background-color: var(--color-gray-200);
  color: var(--color-gray-700);
  border-color: var(--color-gray-200);
}

.btn-secondary:hover {
  background-color: var(--color-gray-300);
  border-color: var(--color-gray-300);
}

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

.btn-success:hover {
  background-color: #059669;
  border-color: #059669;
}

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

.btn-danger:hover {
  background-color: #dc2626;
  border-color: #dc2626;
}

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

.btn-warning:hover {
  background-color: #d97706;
  border-color: #d97706;
}

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

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

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

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

.btn-sm {
  padding: var(--spacing-1) var(--spacing-2);
  font-size: var(--font-size-sm);
}

.btn-lg {
  padding: var(--spacing-3) var(--spacing-6);
  font-size: var(--font-size-lg);
}

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

.btn-icon {
  padding: var(--spacing-2);
}

.btn-icon svg {
  width: 20px;
  height: 20px;
}

/* === FORMULARIOS === */
.form-group {
  margin-bottom: var(--spacing-4);
}

.form-label {
  display: block;
  margin-bottom: var(--spacing-1);
  font-weight: 500;
  color: var(--color-gray-700);
}

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

.form-control {
  display: block;
  width: 100%;
  padding: var(--spacing-2) var(--spacing-3);
  font-size: var(--font-size-base);
  line-height: 1.5;
  color: var(--color-dark);
  background-color: var(--color-white);
  border: 1px solid var(--color-gray-300);
  border-radius: var(--border-radius);
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.form-control:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(30, 58, 95, 0.15);
}

.form-control:disabled {
  background-color: var(--color-gray-100);
  cursor: not-allowed;
}

.form-control::placeholder {
  color: var(--color-gray-400);
}

.form-control.is-invalid,
.form-control:invalid:not(:placeholder-shown) {
  border-color: var(--color-danger);
}

.form-control.is-invalid:focus {
  box-shadow: 0 0 0 3px rgba(239, 68, 68, 0.15);
}

.form-select {
  display: block;
  width: 100%;
  padding: var(--spacing-2) var(--spacing-3);
  padding-right: var(--spacing-8);
  font-size: var(--font-size-base);
  line-height: 1.5;
  color: var(--color-dark);
  background-color: var(--color-white);
  background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 16 16'%3e%3cpath fill='none' stroke='%23374151' stroke-linecap='round' stroke-linejoin='round' stroke-width='2' d='M2 5l6 6 6-6'/%3e%3c/svg%3e");
  background-repeat: no-repeat;
  background-position: right 0.75rem center;
  background-size: 16px 12px;
  border: 1px solid var(--color-gray-300);
  border-radius: var(--border-radius);
  appearance: none;
  cursor: pointer;
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.form-select:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(30, 58, 95, 0.15);
}

.form-textarea {
  min-height: 100px;
  resize: vertical;
}

.form-checkbox,
.form-radio {
  display: inline-flex;
  align-items: center;
  gap: var(--spacing-2);
  cursor: pointer;
}

.form-checkbox input,
.form-radio input {
  width: 18px;
  height: 18px;
  cursor: pointer;
  accent-color: var(--color-primary);
}

.form-error {
  display: block;
  margin-top: var(--spacing-1);
  font-size: var(--font-size-sm);
  color: var(--color-danger);
}

.form-help {
  display: block;
  margin-top: var(--spacing-1);
  font-size: var(--font-size-sm);
  color: var(--color-gray-500);
}

.form-inline {
  display: flex;
  align-items: center;
  gap: var(--spacing-2);
}

/* === TABLAS === */
.table {
  width: 100%;
  border-collapse: collapse;
  background-color: var(--color-white);
}

.table th {
  padding: var(--spacing-3) var(--spacing-4);
  text-align: left;
  font-weight: 600;
  color: var(--color-white);
  background-color: var(--color-primary);
  border-bottom: 2px solid var(--color-primary-dark);
}

.table th:first-child {
  border-top-left-radius: var(--border-radius);
}

.table th:last-child {
  border-top-right-radius: var(--border-radius);
}

.table td {
  padding: var(--spacing-3) var(--spacing-4);
  border-bottom: 1px solid var(--color-gray-200);
  vertical-align: middle;
}

.table tbody tr:last-child td {
  border-bottom: none;
}

.table-striped tbody tr:nth-child(even) {
  background-color: var(--color-gray-50, #f9fafb);
}

.table-hover tbody tr:hover {
  background-color: var(--color-gray-100);
}

.table-responsive {
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  border-radius: var(--border-radius);
  box-shadow: var(--shadow);
}

.table-actions {
  display: flex;
  gap: var(--spacing-2);
  justify-content: flex-end;
}

.table-empty {
  text-align: center;
  padding: var(--spacing-8);
  color: var(--color-gray-500);
}

/* === CARDS === */
.card {
  background-color: var(--color-white);
  border-radius: var(--border-radius-lg);
  box-shadow: var(--shadow);
  overflow: hidden;
}

.card-header {
  padding: var(--spacing-4);
  border-bottom: 1px solid var(--color-gray-200);
  background-color: var(--color-gray-50, #f9fafb);
}

.card-body {
  padding: var(--spacing-4);
}

.card-footer {
  padding: var(--spacing-4);
  border-top: 1px solid var(--color-gray-200);
  background-color: var(--color-gray-50, #f9fafb);
}

.card-title {
  font-size: var(--font-size-lg);
  font-weight: 600;
  margin-bottom: var(--spacing-2);
}

.card-hover {
  transition: transform var(--transition-base), box-shadow var(--transition-base);
}

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

/* === ALERTAS === */
.alert {
  padding: var(--spacing-3) var(--spacing-4);
  border-radius: var(--border-radius);
  margin-bottom: var(--spacing-4);
  border: 1px solid transparent;
}

.alert-success {
  background-color: var(--color-success-light);
  border-color: var(--color-success);
  color: #065f46;
}

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

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

.alert-info {
  background-color: var(--color-info-light);
  border-color: var(--color-info);
  color: #1e40af;
}

/* === TOASTS / NOTIFICACIONES === */
.toast-container {
  position: fixed;
  top: var(--spacing-4);
  right: var(--spacing-4);
  z-index: var(--z-toast);
  display: flex;
  flex-direction: column;
  gap: var(--spacing-2);
  pointer-events: none;
}

.toast {
  padding: var(--spacing-3) var(--spacing-4);
  border-radius: var(--border-radius);
  background-color: var(--color-dark);
  color: var(--color-white);
  box-shadow: var(--shadow-lg);
  pointer-events: auto;
  animation: toastSlideIn var(--transition-slow) ease;
  max-width: 350px;
}

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

.toast.toast-error {
  background-color: var(--color-danger);
}

.toast.toast-warning {
  background-color: var(--color-warning);
}

.toast.toast-info {
  background-color: var(--color-info);
}

.toast.toast-exit {
  animation: toastSlideOut var(--transition-base) ease forwards;
}

@keyframes toastSlideIn {
  from {
    transform: translateX(100%);
    opacity: 0;
  }
  to {
    transform: translateX(0);
    opacity: 1;
  }
}

@keyframes toastSlideOut {
  from {
    transform: translateX(0);
    opacity: 1;
  }
  to {
    transform: translateX(100%);
    opacity: 0;
  }
}

/* === LAYOUT / GRID === */
.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-4);
}

.container-fluid {
  width: 100%;
  padding: 0 var(--spacing-4);
}

.container-sm {
  max-width: 640px;
}

.container-lg {
  max-width: 1024px;
}

.row {
  display: flex;
  flex-wrap: wrap;
  margin: 0 calc(var(--spacing-2) * -1);
}

.col {
  flex: 1;
  padding: 0 var(--spacing-2);
}

.col-12 { width: 100%; flex: 0 0 100%; }
.col-6 { width: 50%; flex: 0 0 50%; }
.col-4 { width: 33.333%; flex: 0 0 33.333%; }
.col-3 { width: 25%; flex: 0 0 25%; }
.col-8 { width: 66.666%; flex: 0 0 66.666%; }
.col-9 { width: 75%; flex: 0 0 75%; }

.gap-1 { gap: var(--spacing-1); }
.gap-2 { gap: var(--spacing-2); }
.gap-3 { gap: var(--spacing-3); }
.gap-4 { gap: var(--spacing-4); }
.gap-5 { gap: var(--spacing-5); }

@media (max-width: 768px) {
  .col-6,
  .col-4,
  .col-3 {
    width: 100%;
    flex: 0 0 100%;
  }
}

/* === NAVBAR === */
.navbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--spacing-3) var(--spacing-4);
  background-color: var(--color-primary);
  color: var(--color-white);
  box-shadow: var(--shadow-md);
}

.navbar-brand {
  display: flex;
  align-items: center;
  gap: var(--spacing-2);
  font-size: var(--font-size-xl);
  font-weight: 600;
  color: var(--color-white);
  text-decoration: none;
}

.navbar-brand:hover {
  text-decoration: none;
  opacity: 0.9;
}

.navbar-nav {
  display: flex;
  align-items: center;
  gap: var(--spacing-1);
}

.nav-link {
  display: flex;
  align-items: center;
  gap: var(--spacing-1);
  padding: var(--spacing-2) var(--spacing-3);
  color: rgba(255, 255, 255, 0.8);
  text-decoration: none;
  border-radius: var(--border-radius);
  transition: all var(--transition-fast);
}

.nav-link:hover {
  color: var(--color-white);
  background-color: rgba(255, 255, 255, 0.1);
  text-decoration: none;
}

.nav-link.active {
  color: var(--color-white);
  background-color: rgba(255, 255, 255, 0.2);
}

.navbar-toggle {
  display: none;
  padding: var(--spacing-2);
  background: none;
  border: none;
  color: var(--color-white);
  cursor: pointer;
}

.navbar-toggle svg {
  width: 24px;
  height: 24px;
}

@media (max-width: 768px) {
  .navbar {
    flex-wrap: wrap;
  }

  .navbar-toggle {
    display: block;
  }

  .navbar-nav {
    display: none;
    width: 100%;
    flex-direction: column;
    align-items: stretch;
    padding-top: var(--spacing-3);
  }

  .navbar-nav.show {
    display: flex;
  }

  .nav-link {
    padding: var(--spacing-3);
    border-radius: 0;
  }
}

/* === MODALES === */
.modal-overlay {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: rgba(0, 0, 0, 0.5);
  z-index: var(--z-modal-backdrop);
  display: none;
  align-items: center;
  justify-content: center;
  padding: var(--spacing-4);
  opacity: 0;
  transition: opacity var(--transition-base);
}

.modal-overlay.show {
  display: flex;
  opacity: 1;
}

.modal {
  background-color: var(--color-white);
  border-radius: var(--border-radius-lg);
  box-shadow: var(--shadow-xl);
  width: 100%;
  max-width: 500px;
  max-height: 90vh;
  display: flex;
  flex-direction: column;
  transform: scale(0.9);
  transition: transform var(--transition-base);
}

.modal-overlay.show .modal {
  transform: scale(1);
}

.modal-sm {
  max-width: 350px;
}

.modal-lg {
  max-width: 800px;
}

.modal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--spacing-4);
  border-bottom: 1px solid var(--color-gray-200);
}

.modal-title {
  font-size: var(--font-size-xl);
  font-weight: 600;
  margin: 0;
}

.modal-close {
  padding: var(--spacing-1);
  background: none;
  border: none;
  color: var(--color-gray-500);
  cursor: pointer;
  border-radius: var(--border-radius);
  transition: all var(--transition-fast);
}

.modal-close:hover {
  color: var(--color-gray-700);
  background-color: var(--color-gray-100);
}

.modal-body {
  padding: var(--spacing-4);
  overflow-y: auto;
  flex: 1;
}

.modal-footer {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: var(--spacing-2);
  padding: var(--spacing-4);
  border-top: 1px solid var(--color-gray-200);
}

/* === BADGES === */
.badge {
  display: inline-flex;
  align-items: center;
  padding: var(--spacing-1) var(--spacing-2);
  font-size: var(--font-size-xs);
  font-weight: 500;
  line-height: 1;
  border-radius: var(--border-radius-full);
  white-space: nowrap;
}

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

.badge-secondary {
  background-color: var(--color-gray-500);
  color: var(--color-white);
}

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

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

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

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

.badge-light {
  background-color: var(--color-gray-200);
  color: var(--color-gray-700);
}

/* === UTILIDADES DE ESPACIADO === */
.m-0 { margin: 0; }
.m-1 { margin: var(--spacing-1); }
.m-2 { margin: var(--spacing-2); }
.m-3 { margin: var(--spacing-3); }
.m-4 { margin: var(--spacing-4); }
.m-5 { margin: var(--spacing-5); }

.mt-0 { margin-top: 0; }
.mt-1 { margin-top: var(--spacing-1); }
.mt-2 { margin-top: var(--spacing-2); }
.mt-3 { margin-top: var(--spacing-3); }
.mt-4 { margin-top: var(--spacing-4); }
.mt-5 { margin-top: var(--spacing-5); }

.mb-0 { margin-bottom: 0; }
.mb-1 { margin-bottom: var(--spacing-1); }
.mb-2 { margin-bottom: var(--spacing-2); }
.mb-3 { margin-bottom: var(--spacing-3); }
.mb-4 { margin-bottom: var(--spacing-4); }
.mb-5 { margin-bottom: var(--spacing-5); }

.ml-0 { margin-left: 0; }
.ml-1 { margin-left: var(--spacing-1); }
.ml-2 { margin-left: var(--spacing-2); }
.ml-3 { margin-left: var(--spacing-3); }
.ml-4 { margin-left: var(--spacing-4); }

.mr-0 { margin-right: 0; }
.mr-1 { margin-right: var(--spacing-1); }
.mr-2 { margin-right: var(--spacing-2); }
.mr-3 { margin-right: var(--spacing-3); }
.mr-4 { margin-right: var(--spacing-4); }

.p-0 { padding: 0; }
.p-1 { padding: var(--spacing-1); }
.p-2 { padding: var(--spacing-2); }
.p-3 { padding: var(--spacing-3); }
.p-4 { padding: var(--spacing-4); }
.p-5 { padding: var(--spacing-5); }

.pt-0 { padding-top: 0; }
.pt-1 { padding-top: var(--spacing-1); }
.pt-2 { padding-top: var(--spacing-2); }
.pt-3 { padding-top: var(--spacing-3); }
.pt-4 { padding-top: var(--spacing-4); }
.pt-5 { padding-top: var(--spacing-5); }

.pb-0 { padding-bottom: 0; }
.pb-1 { padding-bottom: var(--spacing-1); }
.pb-2 { padding-bottom: var(--spacing-2); }
.pb-3 { padding-bottom: var(--spacing-3); }
.pb-4 { padding-bottom: var(--spacing-4); }
.pb-5 { padding-bottom: var(--spacing-5); }

/* === UTILIDADES DE DISPLAY === */
.d-none { display: none; }
.d-block { display: block; }
.d-inline { display: inline; }
.d-inline-block { display: inline-block; }
.d-flex { display: flex; }
.d-inline-flex { display: inline-flex; }
.d-grid { display: grid; }

.flex-row { flex-direction: row; }
.flex-column { flex-direction: column; }
.flex-wrap { flex-wrap: wrap; }
.flex-nowrap { flex-wrap: nowrap; }

.justify-content-start { justify-content: flex-start; }
.justify-content-center { justify-content: center; }
.justify-content-end { justify-content: flex-end; }
.justify-content-between { justify-content: space-between; }
.justify-content-around { justify-content: space-around; }

.align-items-start { align-items: flex-start; }
.align-items-center { align-items: center; }
.align-items-end { align-items: flex-end; }
.align-items-stretch { align-items: stretch; }

.flex-1 { flex: 1; }
.flex-grow-0 { flex-grow: 0; }
.flex-grow-1 { flex-grow: 1; }
.flex-shrink-0 { flex-shrink: 0; }

/* === UTILIDADES DE VISIBILIDAD === */
.hidden {
  display: none !important;
}

.visible {
  visibility: visible;
}

.invisible {
  visibility: hidden;
}

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

/* === ESTADOS DE CARGA === */
.spinner {
  display: inline-block;
  width: 24px;
  height: 24px;
  border: 3px solid var(--color-gray-300);
  border-top-color: var(--color-primary);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

.spinner-sm {
  width: 16px;
  height: 16px;
  border-width: 2px;
}

.spinner-lg {
  width: 40px;
  height: 40px;
  border-width: 4px;
}

@keyframes spin {
  to {
    transform: rotate(360deg);
  }
}

.loading-overlay {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: rgba(255, 255, 255, 0.8);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: var(--z-dropdown);
}

.skeleton {
  background: linear-gradient(90deg, var(--color-gray-200) 25%, var(--color-gray-100) 50%, var(--color-gray-200) 75%);
  background-size: 200% 100%;
  animation: skeleton-loading 1.5s infinite;
  border-radius: var(--border-radius);
}

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

.btn-loading {
  position: relative;
  color: transparent !important;
}

.btn-loading::after {
  content: '';
  position: absolute;
  width: 16px;
  height: 16px;
  border: 2px solid var(--color-white);
  border-top-color: transparent;
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

/* === TOOLBAR === */
.toolbar {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: var(--spacing-3);
  padding: var(--spacing-3) 0;
  margin-bottom: var(--spacing-4);
}

.toolbar-search {
  flex: 1;
  min-width: 200px;
  max-width: 400px;
}

.toolbar-filters {
  display: flex;
  align-items: center;
  gap: var(--spacing-2);
}

.toolbar-actions {
  display: flex;
  align-items: center;
  gap: var(--spacing-2);
  margin-left: auto;
}

@media (max-width: 768px) {
  .toolbar {
    flex-direction: column;
    align-items: stretch;
  }

  .toolbar-search {
    max-width: none;
  }

  .toolbar-actions {
    margin-left: 0;
    justify-content: flex-end;
  }
}

/* === FOOTER === */
.footer {
  padding: var(--spacing-4);
  background-color: var(--color-primary);
  color: rgba(255, 255, 255, 0.8);
  text-align: center;
  margin-top: auto;
}

.footer a {
  color: var(--color-white);
}

/* === PAGE LAYOUT === */
.page {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.page-content {
  flex: 1;
  padding: var(--spacing-4);
}

.page-header {
  margin-bottom: var(--spacing-4);
}

.page-title {
  font-size: var(--font-size-3xl);
  font-weight: 600;
  margin-bottom: var(--spacing-2);
}

/* === BREADCRUMBS === */
.breadcrumb {
  display: flex;
  align-items: center;
  gap: var(--spacing-2);
  font-size: var(--font-size-sm);
  color: var(--color-gray-500);
  margin-bottom: var(--spacing-3);
}

.breadcrumb a {
  color: var(--color-gray-600);
}

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

.breadcrumb-separator {
  color: var(--color-gray-400);
}

/* === EMPTY STATE === */
.empty-state {
  text-align: center;
  padding: var(--spacing-8);
  color: var(--color-gray-500);
}

.empty-state-icon {
  font-size: 48px;
  margin-bottom: var(--spacing-4);
  opacity: 0.5;
}

.empty-state-title {
  font-size: var(--font-size-xl);
  font-weight: 600;
  color: var(--color-gray-700);
  margin-bottom: var(--spacing-2);
}

.empty-state-description {
  margin-bottom: var(--spacing-4);
}