/* ===== 面包屑颜色过渡动画 ===== */
.navbar-tabs a {
  transition: color 0.3s ease, filter 0.3s ease;
  color: #333;
  /* 默认文字颜色 */
}

.navbar-tabs a:hover {
  color: #1775E7;
  /* 悬停主色调 */
}

/* 图标颜色变化 */
.navbar-tabs a:hover .left-arrow,
.navbar-tabs a:hover .home-icon {
  filter: brightness(0) saturate(100%) invert(40%) sepia(90%) saturate(1200%) hue-rotate(200deg);
}

/* 分隔线动画 */
.sign-line {
  transition: color 0.3s ease;
}

.navbar-tabs:hover~.sign-line {
  color: #1775E7;
}

/* ===== 上一篇/下一篇动画 ===== */
.up-down {
  display: flex;
  justify-content: space-between;
  margin-top: 30px;
}

.w-40 {
  width: 48%;
  transition: all 0.3s ease;
}

.up-down-conter {
  padding: 12px;
  background: #f8f9fa;
  border-radius: 4px;
  margin-top: 8px;
  transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
  border-left: 3px solid transparent;
}

.up-down-conter:hover {
  transform: translateX(5px);
  background: #f0f4ff;
  border-left: 3px solid #1775E7;
  box-shadow: 0 2px 8px rgba(23, 117, 231, 0.1);
}