/* ========================================================
   Sidebar — conversation list, actions, footer.
   ======================================================== */

.sidebar {
  width: var(--sidebar-w);
  flex-shrink: 0;
  display: flex;
  flex-direction: column;
  background: var(--c-surface);
  border-right: 1px solid var(--c-border);
  position: relative;
  transition: width var(--transition-normal);
  overflow: hidden;
}

.sidebar.collapsed {
  width: 0;
  border-right: none;
}

.sidebar-inner {
  display: flex;
  flex-direction: column;
  height: 100%;
  min-width: var(--sidebar-w);
}

.sidebar-brand {
  padding: var(--spacing-xl) var(--spacing-xl) var(--spacing-lg);
  font-size: 17px;
  font-weight: 700;
  color: var(--c-text);
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
}

.sidebar-brand .dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--c-accent);
}

.sidebar-actions {
  padding: 0 var(--spacing-lg) var(--spacing-md);
}

.sidebar-list {
  flex: 1;
  overflow-y: auto;
  padding: 0 var(--spacing-md);
}

.sidebar-item {
  padding: 10px var(--spacing-md);
  border-radius: var(--radius-md);
  cursor: pointer;
  font-size: var(--font-size-sm);
  color: var(--c-text-secondary);
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  margin-bottom: 2px;
  transition: all var(--transition-fast);
}

.sidebar-item:hover { background: var(--c-surface-hover); }

.sidebar-item.active {
  background: var(--c-accent-light);
  color: var(--c-accent);
  font-weight: 500;
}

.sidebar-item .icon {
  font-size: 15px;
  opacity: 0.6;
  flex-shrink: 0;
}

.sidebar-item .title {
  flex: 1;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.sidebar-item .badge {
  font-size: var(--font-size-xs);
  background: #e5e7eb;
  color: var(--c-text-secondary);
  padding: 2px 6px;
  border-radius: 10px;
  flex-shrink: 0;
}

.sidebar-item.active .badge {
  background: var(--c-accent);
  color: #fff;
}

.sidebar-item .del-btn {
  opacity: 0;
  flex-shrink: 0;
  width: 22px;
  height: 22px;
  border-radius: 50%;
  border: none;
  background: transparent;
  color: var(--c-text-tertiary);
  cursor: pointer;
  font-size: var(--font-size-base);
  line-height: 22px;
  text-align: center;
  transition: all var(--transition-fast);
}

.sidebar-item:hover .del-btn { opacity: 1; }
.sidebar-item .del-btn:hover { background: var(--c-error-light); color: var(--c-error); }

.sidebar-footer {
  padding: var(--spacing-md) var(--spacing-lg);
  border-top: 1px solid var(--c-border);
  font-size: var(--font-size-sm);
  color: var(--c-text-tertiary);
}

/* Toggle button */
.sidebar-toggle {
  position: absolute;
  right: 0;
  top: 50%;
  transform: translateY(-50%);
  width: 20px;
  height: 48px;
  border: 1px solid var(--c-border);
  border-right: none;
  border-radius: var(--radius-sm) 0 0 var(--radius-sm);
  background: var(--c-surface);
  color: var(--c-text-tertiary);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 10px;
  padding: 0;
  opacity: 0;
  transition: opacity var(--transition-fast), background var(--transition-fast);
  z-index: 10;
}

.sidebar:hover .sidebar-toggle,
.sidebar.collapsed .sidebar-toggle {
  opacity: 1;
}

.sidebar.collapsed .sidebar-toggle {
  right: -20px;
  border-right: 1px solid var(--c-border);
  border-left: none;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
}

.sidebar-toggle:hover {
  background: var(--c-surface-hover);
  color: var(--c-text);
}