.catalog-sticky-wrap {
  position: relative;
  z-index: 99;
  width: 1500px;
  max-width: 100%;
  margin: 0 auto;
}

.catalog-nav {
  display: flex;
  gap: 20px;
  padding: 16px 12px;
  background: #fff;
  width: 100%;
  box-sizing: border-box;
  justify-content: center;
  align-items: center;
  transition: box-shadow 0.2s, padding 0.3s ease;
}

.catalog-nav.is-sticky {
  position: fixed;
  top: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 1500px;
  max-width: 100%;
  box-shadow: 0 4px 12px rgba(0,0,0,0.12);
  background: #fff;
  z-index: 999;
  padding: 8px 12px;
}

.catalog-nav-item {
  flex: 0 0 110px;
  text-align: center;
  cursor: pointer;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
}

.catalog-nav-item .img-box {
  width: 150px;
  height: 150px;
  margin: 0 auto 8px;
  border-radius: 50%;
  overflow: hidden;
  position: relative;
  background: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  border: none;
  outline: none;
  box-shadow: none;
  transition: all 0.3s ease;
}

.catalog-nav.is-sticky .catalog-nav-item .img-box {
  width: 100px;
  height: 100px;
  margin-bottom: 4px;
}

.catalog-nav-item img {
  width: 82%;
  height: 82%;
  object-fit: contain;
  display: block;
}

.catalog-nav-item .img-active { display: none; }
.catalog-nav-item.active .img-normal { display: none; }
.catalog-nav-item.active .img-active { display: block; }
.catalog-nav-item.active .label { color: #f59e0b; }

.catalog-nav-item .label {
  font-size: 15px;
  color: #333;
  line-height: 1.3;
  font-weight: 500;
  transition: all 0.3s ease;
}

.catalog-nav.is-sticky .catalog-nav-item .label {
  font-size: 13px;
}

.catalog-nav::-webkit-scrollbar { height: 6px; }
.catalog-nav::-webkit-scrollbar-thumb { background: #ccc; border-radius: 4px; }

.scroll-hint { display: none; }

@media screen and (max-width: 1000px) {
  .catalog-nav {
    justify-content: flex-start; 
    overflow-x: auto; 
    -webkit-overflow-scrolling: touch; 
    gap: 10px;
    padding: 12px 10px;
  }
  
  .catalog-nav::-webkit-scrollbar {
    display: none; 
  }
  
  .catalog-nav-item {
    flex: 0 0 100px; 
  }
  
  .catalog-nav-item .label {
    font-size: 13px;
    white-space: nowrap; 
  }
  
  .catalog-nav-item .img-box {
    width: 90px;
    height: 90px;
  }

  .catalog-nav.is-sticky .catalog-nav-item .img-box {
    width: 70px;
    height: 70px;
  }
  
  .catalog-nav.is-sticky .catalog-nav-item .label {
    font-size: 12px;
  }

  .scroll-hint {
    display: flex;
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    width: 28px;
    height: 28px;
    background: rgba(255, 255, 255, 0.9);
    border-radius: 50%;
    box-shadow: 0 2px 6px rgba(0,0,0,0.15);
    z-index: 100;
    align-items: center;
    justify-content: center;
    color: #666;
    font-size: 14px;
    cursor: pointer; /* 开启点击小手 */
    transition: opacity 0.3s ease;
  }
  .scroll-hint-left { left: 4px; }
  .scroll-hint-right { right: 4px; }
}