/* ========== 右侧目录栏 ========== */
.toc-sidebar {
  width: var(--toc-width);
  background-color: var(--bg-body);
  display: none;
  flex-direction: column;
  position: fixed;
  right: 0;
  top: var(--header-height);
  height: calc(100vh - var(--header-height) - var(--footer-height));
  overflow: hidden;
  border-left: 1px solid var(--border-light);
  z-index: 99;
  transition: transform 0.2s;
}

.toc-sidebar.collapsed {
  transform: translateX(var(--toc-width));
}

.toc-header {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  font-weight: 500;
  color: var(--text-secondary);
  padding: 12px 16px;
  border-bottom: 1px solid var(--border-light);
  flex-shrink: 0;
}

.toc-header svg {
  color: var(--text-placeholder);
}

.toc-header span {
  flex: 1;
}

.toc-toggle-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 24px;
  height: 24px;
  padding: 0;
  background: transparent;
  border: none;
  color: var(--text-placeholder);
  cursor: pointer;
  border-radius: 4px;
  transition: all 0.15s;
}

.toc-toggle-btn:hover {
  background: var(--bg-hover);
  color: var(--text-body);
}

.toc-toggle-btn svg {
  transition: transform 0.2s;
}

.toc-sidebar.collapsed .toc-toggle-btn svg {
  transform: rotate(180deg);
}

/* 展开按钮 */
.toc-expand-btn {
  display: none;
  position: fixed;
  right: 0;
  top: calc(var(--header-height) + 60px);
  width: 28px;
  height: 40px;
  background: var(--bg-body);
  border: 1px solid var(--border-light);
  border-right: none;
  border-radius: 6px 0 0 6px;
  cursor: pointer;
  z-index: 98;
  align-items: center;
  justify-content: center;
  color: var(--text-placeholder);
  transition: all 0.15s;
  box-shadow: -2px 0 8px rgba(0, 0, 0, 0.06);
}

.toc-expand-btn:hover {
  background: var(--bg-hover);
  color: var(--text-body);
}

.toc-expand-btn.show {
  display: flex;
}

.toc-nav {
  flex: 1;
  overflow-y: auto;
  padding: 8px;
  font-size: 13px;
}

.toc-nav ul {
  list-style: none;
}

.toc-nav a {
  display: block;
  padding: 6px 12px;
  color: var(--text-secondary);
  text-decoration: none;
  border-radius: 6px;
  transition: all 0.15s;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.toc-nav a:hover {
  background: var(--bg-hover);
  color: var(--text-body);
}

.toc-nav a.active {
  background: var(--bg-active);
  color: var(--primary);
}

.toc-nav .toc-h2 a { padding-left: 12px; }
.toc-nav .toc-h3 a { padding-left: 24px; font-size: 12px; }
.toc-nav .toc-h4 a { padding-left: 36px; font-size: 12px; }

/* 目录栏滚动条 */
.toc-sidebar::-webkit-scrollbar,
.toc-nav::-webkit-scrollbar {
  width: 4px;
}

.toc-sidebar::-webkit-scrollbar-track,
.toc-nav::-webkit-scrollbar-track {
  background: transparent;
}

.toc-sidebar::-webkit-scrollbar-thumb,
.toc-nav::-webkit-scrollbar-thumb {
  background: var(--text-disabled);
  border-radius: 2px;
}

.toc-sidebar::-webkit-scrollbar-thumb:hover,
.toc-nav::-webkit-scrollbar-thumb:hover {
  background: var(--text-placeholder);
}