#tab-chat {
  flex-direction: row;
}

.thread-sidebar {
  width: 220px;
  background: var(--glass-bg);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  border-right: 1px solid var(--glass-border);
  display: flex;
  flex-direction: column;
  flex-shrink: 0;
  transition: width var(--duration-slow) var(--ease);
  overflow: hidden;
}

.thread-sidebar.collapsed {
  width: 36px;
}

.thread-sidebar.collapsed .thread-sidebar-header span,
.thread-sidebar.collapsed .thread-new-btn,
.thread-sidebar.collapsed .thread-list,
.thread-sidebar.collapsed .assistant-item,
.thread-sidebar.collapsed .threads-section-header {
  display: none;
}

.thread-sidebar-header {
  display: flex;
  align-items: center;
  padding: 10px 12px;
  border-bottom: 1px solid var(--border);
  font-size: 13px;
  font-weight: 600;
  gap: 8px;
}

.thread-sidebar-header span {
  flex: 1;
}

.thread-new-btn {
  background: none;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--accent);
  cursor: pointer;
  font-size: 16px;
  width: 24px;
  height: 24px;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 0;
  line-height: 1;
}

.thread-new-btn:hover {
  background: rgba(255, 26, 26, 0.12);
}

.assistant-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px 12px;
  cursor: pointer;
  font-size: 13px;
  font-weight: 600;
  color: var(--text);
  border-bottom: 1px solid var(--border);
  background: var(--bg-secondary);
}

.assistant-item:hover {
  background: var(--bg-tertiary);
}

.assistant-item.active {
  background: rgba(255, 26, 26, 0.08);
  color: var(--accent);
  border-left: 2px solid var(--accent);
}

.assistant-label {
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.assistant-meta {
  font-size: 11px;
  font-weight: 400;
  color: var(--text-secondary);
}

.threads-section-header {
  padding: 8px 12px 4px;
  font-size: 11px;
  font-weight: 500;
  display: flex;
  align-items: center;
  justify-content: space-between;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  color: var(--text-secondary);
}

.thread-clear-btn {
  border: 1px solid var(--border);
  background: transparent;
  color: var(--text-secondary);
  border-radius: 8px;
  font-size: 10px;
  padding: 2px 6px;
  cursor: pointer;
}

.thread-clear-btn:hover {
  color: var(--text);
  border-color: var(--accent);
}

.thread-toggle-btn {
  background: none;
  border: none;
  color: var(--text-secondary);
  cursor: pointer;
  font-size: 14px;
  padding: 2px;
}

.thread-toggle-btn:hover {
  color: var(--text);
}

.thread-list {
  flex: 1;
  overflow-y: auto;
}

.thread-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 8px 12px;
  cursor: pointer;
  font-size: 13px;
  color: var(--text-secondary);
  border-bottom: 1px solid rgba(255, 255, 255, 0.03);
}

.thread-item:hover {
  background: rgba(255, 255, 255, 0.03);
  color: var(--text);
}

.thread-item.active {
  background: var(--accent-subtle);
  color: var(--accent);
  border-left: 2px solid var(--accent);
}

.thread-label {
  font-family: monospace;
  font-size: 12px;
}

.thread-meta {
  font-size: 11px;
  color: var(--text-secondary);
}

.thread-actions {
  display: flex;
  align-items: center;
  gap: 8px;
}

.thread-delete-btn {
  border: 1px solid var(--border);
  background: transparent;
  color: var(--text-secondary);
  border-radius: 8px;
  font-size: 10px;
  padding: 2px 6px;
  cursor: pointer;
}

.thread-delete-btn:hover {
  color: #ff8f8f;
  border-color: #b34646;
}