/* Reusable component library: buttons, inputs, cards, tables, feedback,
   badges, modals, tabs. Shared by all four surfaces. */

/* ---------------------------------------------------------------- */
/* Buttons                                                           */
/* ---------------------------------------------------------------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  min-height: var(--touch-target);
  padding: 0 var(--space-5);
  border-radius: var(--radius-md);
  border: 1px solid transparent;
  font-size: var(--font-size-sm);
  font-weight: 600;
  cursor: pointer;
  transition: background var(--duration-fast) var(--ease-standard),
    border-color var(--duration-fast) var(--ease-standard),
    transform var(--duration-fast) var(--ease-standard);
  white-space: nowrap;
}

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

.btn svg {
  width: 18px;
  height: 18px;
  flex-shrink: 0;
}

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

.btn-secondary {
  background: var(--color-secondary);
  color: #fff;
}
.btn-secondary:hover { background: var(--color-secondary-dark); }

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

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

.btn-danger {
  background: var(--color-danger);
  color: #fff;
}
.btn-danger:hover { background: #a53c2f; }

.btn-success {
  background: var(--color-success);
  color: #fff;
}

.btn-sm {
  min-height: 36px;
  padding: 0 var(--space-3);
  font-size: var(--font-size-xs);
}

.btn-block { width: 100%; }

.btn-icon {
  min-height: var(--touch-target);
  min-width: var(--touch-target);
  padding: 0;
  border-radius: var(--radius-full);
  background: transparent;
  color: var(--color-text);
}
.btn-icon:hover { background: var(--color-surface-alt); }

.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

/* ---------------------------------------------------------------- */
/* Inputs                                                            */
/* ---------------------------------------------------------------- */
.field {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
  margin-bottom: var(--space-4);
}

.field-label {
  font-size: var(--font-size-sm);
  font-weight: 600;
  color: var(--color-text);
}

.field-hint {
  font-size: var(--font-size-xs);
  color: var(--color-muted);
}

.field-error {
  font-size: var(--font-size-xs);
  color: var(--color-danger);
  display: none;
}

.field.has-error .field-error { display: block; }
.field.has-error .input,
.field.has-error select.input,
.field.has-error textarea.input {
  border-color: var(--color-danger);
}

.input {
  width: 100%;
  min-height: var(--touch-target);
  padding: var(--space-2) var(--space-4);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  background: var(--color-surface);
  color: var(--color-text);
  font-size: var(--font-size-base);
  font-family: inherit;
}

.input:focus {
  border-color: var(--color-primary);
  outline: 2px solid var(--color-primary-light);
  outline-offset: 0;
}

textarea.input {
  min-height: 100px;
  padding-top: var(--space-3);
  resize: vertical;
}

.input-search {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  padding: 0 var(--space-3);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-full);
  background: var(--color-surface);
  min-height: var(--touch-target);
}

.input-search svg {
  width: 18px;
  height: 18px;
  color: var(--color-muted);
  flex-shrink: 0;
}

.input-search input {
  border: 0;
  outline: 0;
  background: transparent;
  flex: 1;
  min-width: 0;
  font-size: var(--font-size-base);
  font-family: inherit;
  min-height: 44px;
}

.checkbox-row,
.radio-row {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  min-height: var(--touch-target);
}

.checkbox-row input,
.radio-row input {
  width: 22px;
  height: 22px;
  accent-color: var(--color-primary);
  flex-shrink: 0;
}

.toggle {
  position: relative;
  display: inline-flex;
  align-items: center;
  width: 48px;
  height: 28px;
  flex-shrink: 0;
}

.toggle input {
  opacity: 0;
  width: 100%;
  height: 100%;
  position: absolute;
  margin: 0;
  cursor: pointer;
  z-index: 1;
}

.toggle-track {
  position: absolute;
  inset: 0;
  background: var(--color-border);
  border-radius: var(--radius-full);
  transition: background var(--duration-fast) var(--ease-standard);
}

.toggle-thumb {
  position: absolute;
  top: 3px;
  left: 3px;
  width: 22px;
  height: 22px;
  background: #fff;
  border-radius: 50%;
  box-shadow: var(--shadow-sm);
  transition: transform var(--duration-fast) var(--ease-standard);
}

.toggle input:checked ~ .toggle-track { background: var(--color-primary); }
.toggle input:checked ~ .toggle-thumb { transform: translateX(20px); }

/* ---------------------------------------------------------------- */
/* Cards                                                             */
/* ---------------------------------------------------------------- */
.card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-5);
}

.card-flat {
  background: var(--color-surface-alt);
  border-radius: var(--radius-lg);
  padding: var(--space-5);
}

.card-title {
  font-size: var(--font-size-md);
  font-weight: 700;
  margin-bottom: var(--space-1);
}

.card-row {
  display: flex;
  align-items: center;
  gap: var(--space-3);
}

.stat-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-5);
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.stat-card .stat-icon {
  width: 40px;
  height: 40px;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--color-primary-light);
  color: var(--color-primary-dark);
}

.stat-card .stat-value {
  font-size: var(--font-size-2xl);
  font-weight: 700;
}

.stat-card .stat-label {
  font-size: var(--font-size-sm);
  color: var(--color-muted);
}

.stat-card .stat-delta {
  font-size: var(--font-size-xs);
  font-weight: 600;
}
.stat-delta.is-up { color: var(--color-success); }
.stat-delta.is-down { color: var(--color-danger); }

.avatar {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--color-secondary-light);
  color: var(--color-secondary-dark);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  flex-shrink: 0;
  overflow: hidden;
}

.avatar-sm { width: 32px; height: 32px; font-size: var(--font-size-xs); }
.avatar-lg { width: 72px; height: 72px; font-size: var(--font-size-lg); }

.list-card {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: var(--space-4);
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  margin-bottom: var(--space-3);
}

.list-card:hover { border-color: var(--color-primary); }

/* Entrance animation for cards appearing in a list */
@keyframes card-enter {
  from { opacity: 0; transform: translateY(6px); }
  to { opacity: 1; transform: translateY(0); }
}
.card-enter { animation: card-enter var(--duration-base) var(--ease-standard) both; }

/* ---------------------------------------------------------------- */
/* Badges / status                                                   */
/* ---------------------------------------------------------------- */
.badge {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  padding: var(--space-1) var(--space-3);
  border-radius: var(--radius-full);
  font-size: var(--font-size-xs);
  font-weight: 600;
  white-space: nowrap;
}

.badge-success { background: var(--color-success-bg); color: var(--color-success); }
.badge-danger { background: var(--color-danger-bg); color: var(--color-danger); }
.badge-warning { background: var(--color-warning-bg); color: var(--color-warning); }
.badge-info { background: var(--color-info-bg); color: var(--color-info); }
.badge-neutral { background: var(--color-surface-alt); color: var(--color-muted); }

.status-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  display: inline-block;
  flex-shrink: 0;
}
.status-dot.is-success { background: var(--color-success); }
.status-dot.is-danger { background: var(--color-danger); }
.status-dot.is-warning { background: var(--color-warning); }
.status-dot.is-muted { background: var(--color-muted); }

/* ---------------------------------------------------------------- */
/* Tabs                                                              */
/* ---------------------------------------------------------------- */
.tabs {
  display: flex;
  gap: var(--space-2);
  border-bottom: 1px solid var(--color-border);
  overflow-x: auto;
  margin-bottom: var(--space-5);
}

.tab {
  padding: var(--space-3) var(--space-4);
  font-size: var(--font-size-sm);
  font-weight: 600;
  color: var(--color-muted);
  border-bottom: 2px solid transparent;
  white-space: nowrap;
  min-height: var(--touch-target);
}

.tab.is-active {
  color: var(--color-primary-dark);
  border-bottom-color: var(--color-primary);
}

/* ---------------------------------------------------------------- */
/* Tables                                                            */
/* ---------------------------------------------------------------- */
.table-wrap {
  overflow-x: auto;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  background: var(--color-surface);
}

.table {
  width: 100%;
  min-width: 640px;
}

.table th,
.table td {
  text-align: left;
  padding: var(--space-3) var(--space-4);
  font-size: var(--font-size-sm);
  border-bottom: 1px solid var(--color-border);
}

.table th {
  color: var(--color-muted);
  font-weight: 600;
  background: var(--color-surface-alt);
  white-space: nowrap;
}

.table tr:last-child td { border-bottom: 0; }
.table tr:hover td { background: var(--color-surface-alt); }

/* Mobile: table rows become stacked cards */
@media (max-width: 767px) {
  .table-stack thead { display: none; }
  .table-stack,
  .table-stack tbody,
  .table-stack tr,
  .table-stack td {
    display: block;
    width: 100%;
  }
  .table-stack tr {
    border-bottom: 1px solid var(--color-border);
    padding: var(--space-3) var(--space-4);
  }
  .table-stack td {
    padding: var(--space-1) 0;
    border: 0;
    display: flex;
    justify-content: space-between;
    gap: var(--space-3);
  }
  .table-stack td::before {
    content: attr(data-label);
    font-weight: 600;
    color: var(--color-muted);
    flex-shrink: 0;
  }
}

/* ---------------------------------------------------------------- */
/* Modal / bottom sheet / dropdown                                   */
/* ---------------------------------------------------------------- */
.modal-backdrop {
  position: fixed;
  inset: 0;
  background: var(--color-overlay);
  z-index: var(--z-modal);
  display: none;
  align-items: center;
  justify-content: center;
  padding: var(--space-4);
}

.modal-backdrop.is-open { display: flex; }

.modal {
  background: var(--color-surface);
  border-radius: var(--radius-lg);
  padding: var(--space-6);
  width: 100%;
  max-width: 480px;
  max-height: 90vh;
  overflow-y: auto;
  box-shadow: var(--shadow-lg);
  animation: modal-in var(--duration-base) var(--ease-standard) both;
}

@keyframes modal-in {
  from { opacity: 0; transform: translateY(12px) scale(0.98); }
  to { opacity: 1; transform: translateY(0) scale(1); }
}

.modal-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: var(--space-4);
  margin-bottom: var(--space-4);
}

.modal-title { font-size: var(--font-size-md); font-weight: 700; }

.modal-actions {
  display: flex;
  justify-content: flex-end;
  gap: var(--space-3);
  margin-top: var(--space-5);
  flex-wrap: wrap;
}

/* Bottom sheet — mobile pattern for the same "modal" markup */
@media (max-width: 767px) {
  .modal-backdrop.as-sheet { align-items: flex-end; padding: 0; }
  .modal-backdrop.as-sheet .modal {
    max-width: none;
    width: 100%;
    border-radius: var(--radius-lg) var(--radius-lg) 0 0;
    animation: sheet-in var(--duration-base) var(--ease-standard) both;
  }
}

@keyframes sheet-in {
  from { transform: translateY(100%); }
  to { transform: translateY(0); }
}

.dropdown {
  position: relative;
  display: inline-block;
}

.dropdown-menu {
  position: absolute;
  top: calc(100% + var(--space-2));
  right: 0;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-md);
  min-width: 200px;
  padding: var(--space-2);
  z-index: var(--z-nav);
  display: none;
}

.dropdown.is-open .dropdown-menu { display: block; }

.dropdown-item {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-2) var(--space-3);
  border-radius: var(--radius-sm);
  font-size: var(--font-size-sm);
  min-height: 40px;
  width: 100%;
  text-align: left;
  background: transparent;
  border: 0;
  cursor: pointer;
}

.dropdown-item:hover { background: var(--color-surface-alt); }

/* ---------------------------------------------------------------- */
/* Feedback: toast, alert, empty/loading/error/success states        */
/* ---------------------------------------------------------------- */
.toast-region {
  position: fixed;
  top: var(--space-4);
  right: var(--space-4);
  left: var(--space-4);
  z-index: var(--z-toast);
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: var(--space-2);
  pointer-events: none;
}

.toast {
  pointer-events: auto;
  display: flex;
  align-items: center;
  gap: var(--space-2);
  background: var(--color-text);
  color: #fff;
  padding: var(--space-3) var(--space-4);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-lg);
  font-size: var(--font-size-sm);
  max-width: 360px;
  animation: toast-in var(--duration-base) var(--ease-standard) both;
}

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

@keyframes toast-in {
  from { opacity: 0; transform: translateY(-8px); }
  to { opacity: 1; transform: translateY(0); }
}

.alert {
  display: flex;
  gap: var(--space-3);
  padding: var(--space-4);
  border-radius: var(--radius-md);
  border: 1px solid transparent;
  font-size: var(--font-size-sm);
}

.alert svg { flex-shrink: 0; width: 20px; height: 20px; }
.alert-info { background: var(--color-info-bg); color: var(--color-info); }
.alert-success { background: var(--color-success-bg); color: var(--color-success); }
.alert-warning { background: var(--color-warning-bg); color: var(--color-warning); }
.alert-danger { background: var(--color-danger-bg); color: var(--color-danger); }

.empty-state {
  text-align: center;
  padding: var(--space-10) var(--space-4);
  color: var(--color-muted);
}

.empty-state svg {
  width: 56px;
  height: 56px;
  margin: 0 auto var(--space-4);
  color: var(--color-border);
}

.empty-state-title {
  font-size: var(--font-size-md);
  font-weight: 700;
  color: var(--color-text);
  margin-bottom: var(--space-1);
}

.skeleton {
  background: linear-gradient(90deg, var(--color-surface-alt) 25%, var(--color-border) 37%, var(--color-surface-alt) 63%);
  background-size: 400% 100%;
  animation: skeleton-loading 1.4s ease infinite;
  border-radius: var(--radius-sm);
}

@keyframes skeleton-loading {
  0% { background-position: 100% 50%; }
  100% { background-position: 0 50%; }
}

.spinner {
  width: 20px;
  height: 20px;
  border: 3px solid var(--color-border);
  border-top-color: var(--color-primary);
  border-radius: 50%;
  animation: spin 0.7s linear infinite;
}

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

/* ---------------------------------------------------------------- */
/* Pagination / filters                                              */
/* ---------------------------------------------------------------- */
.pagination {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  flex-wrap: wrap;
}

.pagination button {
  min-width: var(--touch-target);
  min-height: var(--touch-target);
  border-radius: var(--radius-sm);
  border: 1px solid var(--color-border);
  background: var(--color-surface);
  cursor: pointer;
}

.pagination button.is-active {
  background: var(--color-primary);
  border-color: var(--color-primary);
  color: #fff;
}

.filter-bar {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-3);
  align-items: center;
  margin-bottom: var(--space-5);
}

.chip {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  padding: var(--space-2) var(--space-4);
  border-radius: var(--radius-full);
  border: 1px solid var(--color-border);
  font-size: var(--font-size-sm);
  font-weight: 500;
  cursor: pointer;
  background: var(--color-surface);
  min-height: 40px;
}

.chip.is-active {
  background: var(--color-primary);
  border-color: var(--color-primary);
  color: #fff;
}

/* Attendance marking chips (Teacher attendance screen) */
.attendance-chip {
  min-width: 96px;
  justify-content: center;
  font-weight: 600;
}
.attendance-chip.is-present { background: var(--color-success-bg); border-color: var(--color-success); color: var(--color-success); }
.attendance-chip.is-absent { background: var(--color-danger-bg); border-color: var(--color-danger); color: var(--color-danger); }
.attendance-chip.is-late { background: var(--color-warning-bg); border-color: var(--color-warning); color: var(--color-warning); }

/* Gallery upload preview grid + progress bar */
.gallery-preview-grid {
  display: none;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-3);
  margin: var(--space-4) 0;
}
.gallery-preview-grid .gallery-thumb {
  aspect-ratio: 1;
  border-radius: var(--radius-md);
  background: var(--color-secondary-light);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-secondary-dark);
}
.upload-progress {
  display: none;
  height: 8px;
  border-radius: var(--radius-full);
  background: var(--color-border);
  overflow: hidden;
  margin: var(--space-3) 0;
}
.upload-progress .skeleton {
  height: 100%;
  width: 0%;
  background: var(--color-primary);
  animation: none;
  border-radius: var(--radius-full);
}