/* Layer Panel UI */
.layer-item {
  display: flex;
  align-items: center;
  padding: 8px 10px;
  background: var(--panel-bg);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  margin-bottom: 6px;
  cursor: pointer;
  transition: all var(--transition-fast);
  box-shadow: var(--shadow-sm);
}
.layer-item:hover {
  border-color: var(--primary-light);
  transform: translateY(-1px);
}
.layer-item.active {
  border-color: var(--primary-color);
  background-color: var(--primary-light);
  color: var(--primary-color);
  font-weight: 500;
}
.layer-item .icon {
  margin-right: 10px;
  opacity: 0.7;
}
.layer-item.active .icon {
  opacity: 1;
}
.layer-item-ghost {
  opacity: 0.4;
  background-color: var(--bg-color);
  border: 1px dashed var(--primary-color);
}
.layer-item .drag-handle:hover {
  opacity: 1 !important;
  color: var(--primary-color);
}

/* ── Layer Groups ── */
.layer-group {
  margin-bottom: 6px;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  overflow: hidden;
}

.layer-group-header {
  display: flex;
  align-items: center;
  padding: 7px 10px;
  background: var(--bg-color);
  cursor: pointer;
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--text-color);
  user-select: none;
  list-style: none;
}

.layer-group-header::-webkit-details-marker {
  display: none;
}

.layer-group-header::before {
  content: "▶";
  font-size: 0.6rem;
  margin-right: 8px;
  transition: transform 0.15s ease;
  opacity: 0.5;
}

.layer-group[open] > .layer-group-header::before {
  transform: rotate(90deg);
}

.layer-group-name {
  flex: 1;
}

.layer-group-count {
  font-size: 0.68rem;
  font-weight: 400;
  color: var(--text-muted);
  background: var(--border-color);
  padding: 1px 6px;
  border-radius: 10px;
  margin-right: 6px;
}

.layer-group-delete {
  background: none;
  border: none;
  color: var(--text-muted);
  cursor: pointer;
  font-size: 1rem;
  line-height: 1;
  padding: 0 4px;
  opacity: 0;
  transition:
    opacity 0.15s,
    color 0.15s;
}

.layer-group-header:hover .layer-group-delete {
  opacity: 1;
}

.layer-group-delete:hover {
  color: #ef4444;
}

.layer-group-content {
  padding: 4px 4px 4px 16px;
  background: var(--panel-bg);
}

.layer-group-content .layer-item {
  margin-bottom: 4px;
  font-size: 0.78rem;
  padding: 6px 8px;
}

/* ── Add Group Button (inline with heading) ── */
.sidebar-heading {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.layer-add-group-btn {
  background: none;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  color: var(--text-muted);
  cursor: pointer;
  font-size: 0.8rem;
  font-weight: 600;
  padding: 1px 7px;
  line-height: 1.2;
  transition: all 0.15s ease;
}

.layer-add-group-btn:hover {
  background: var(--primary-light);
  border-color: var(--primary-color);
  color: var(--primary-color);
}

/* ── Properties Panel ── */
.properties-panel {
  font-size: 0.8rem;
}

.properties-panel .empty-state {
  color: var(--text-muted);
  font-size: 0.78rem;
  text-align: center;
  padding: 24px 8px;
  line-height: 1.6;
}

.prop-section {
  margin-bottom: 16px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--border-color);
}

.prop-section:last-child {
  border-bottom: none;
  margin-bottom: 0;
}

.prop-section h3 {
  font-size: 0.65rem;
  text-transform: uppercase;
  color: var(--text-muted);
  letter-spacing: 0.08em;
  font-weight: 600;
  margin-bottom: 10px;
}

.prop-section .form-group {
  margin-bottom: 8px;
}

.prop-section .form-group label {
  font-size: 0.7rem;
  margin-bottom: 3px;
}

.prop-section .form-group input,
.prop-section .form-group select {
  padding: 5px 8px;
  font-size: 0.8rem;
}

.prop-section .form-group.row {
  display: flex;
  gap: 6px;
}

.prop-section .form-group.row .col {
  flex: 1;
}

.prop-section .form-group.row .btn {
  flex: 1;
  font-size: 0.7rem;
  padding: 5px 8px;
}

.delete-section {
  padding-top: 8px;
  border-bottom: none;
}

.delete-section .btn {
  font-size: 0.75rem;
  padding: 7px 12px;
}