.sidebar-left {
  width: 100%;
  height: 100%;
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

.sidebar-tabs {
  display: flex;
  border-bottom: 1px solid var(--color-border);
  background-color: var(--color-bg-tertiary);
  padding: 0 var(--spacing-sm);
  flex-shrink: 0;
}

.tab-button {
  flex: 1;
  padding: var(--spacing-md) var(--spacing-sm);
  background: none;
  border: none;
  border-bottom: 2px solid transparent;
  cursor: pointer;
  transition: all var(--transition-normal);
  font-size: 13px;
  color: var(--color-text-secondary);
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-xs);
  font-weight: 500;
}

.tab-button:hover {
  background-color: var(--color-bg-elevated);
  color: var(--color-text-primary);
}

.tab-button.active {
  color: var(--color-accent);
  font-weight: 600;
  border-bottom-color: var(--color-accent);
  background: var(--color-accent-ultra-light);
}

.sidebar-content {
  flex: 1;
  overflow-y: auto;
  padding: 0; /* ✅ 移除padding，滚动条作为间隔 */
  min-height: 0;
}

/* ✅ 美化滚动条 - 符合主题 */
.sidebar-content::-webkit-scrollbar {
  width: 8px;
}

.sidebar-content::-webkit-scrollbar-track {
  background: transparent;
}

.sidebar-content::-webkit-scrollbar-thumb {
  background: var(--color-scrollbar);
  border-radius: 4px;
  transition: all 0.2s ease;
}

.sidebar-content::-webkit-scrollbar-thumb:hover {
  background: var(--color-scrollbar-hover);
}

/* Tab placeholder for empty states */
.tab-placeholder {
  padding: var(--spacing-lg);
  height: 100%;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  color: var(--color-text-muted);
}

.tab-placeholder h3 {
  font-size: 1rem;
  font-weight: 600;
  color: var(--color-text-primary);
  margin-bottom: var(--spacing-sm);
}

.tab-placeholder p {
  font-size: 0.85rem;
  line-height: 1.5;
}