#web_bg {
  position: fixed;
  z-index: -999;
  width: 100%;
  height: 100%;
  background-attachment: local;
  background-position: center;
  -webkit-background-size: cover;
  -moz-background-size: cover;
  background-size: cover;
  background-repeat: repeat;
}

/* 目录样式自定义（原有） */
.toc-header {
  color: white !important;
}

.tocbot-link {
  color: white !important;
}