/* 主站文档页沿用的品牌页脚，以及教程站公共的返回顶部按钮。 */
.siteFooter {
  margin-top: 44px;
  padding: 26px 20px;
  color: #fff;
  background: linear-gradient(135deg, #176b47, #0f5139);
}
.siteFooterInner {
  display: grid;
  grid-template-columns: minmax(180px, 1fr) minmax(300px, 2fr) minmax(180px, 1fr);
  align-items: center;
  gap: 28px;
  max-width: 60rem;
  margin: 0 auto;
}
.siteFooterBrand h2 {
  margin: 0 0 12px;
  font-size: 17px;
  font-weight: 700;
}
.siteFooterBrand img {
  display: block;
  width: min(200px, 100%);
  height: auto;
  margin: 0;
}
.siteFooterLegal { text-align: center; }
.siteFooterLegal ul {
  margin: 0;
  padding: 0;
  list-style: none;
  font-size: 13px;
  line-height: 1.9;
}
.siteFooter a {
  color: #fff;
  text-decoration: none;
}
.siteFooter a:hover { text-decoration: underline; }
.siteFooterFollow {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 12px;
  font-size: 12px;
  line-height: 1.7;
  white-space: nowrap;
}
.siteFooterFollow img {
  display: block;
  width: 86px;
  height: 86px;
  margin: 0;
  border-radius: 6px;
}
.siteBackTop {
  position: fixed;
  right: 24px;
  bottom: 26px;
  z-index: 80;
  display: grid;
  place-items: center;
  width: 42px;
  height: 42px;
  padding: 0;
  color: #fff;
  background: linear-gradient(145deg, #2c9b61, #176b47);
  border: 1px solid rgba(255, 255, 255, .45);
  border-radius: 50%;
  opacity: .78;
  box-shadow: 0 7px 18px rgba(21, 63, 43, .22), inset 0 1px 0 rgba(255, 255, 255, .2);
  cursor: pointer;
  transition: transform .18s ease, box-shadow .18s ease, filter .18s ease, opacity .18s ease;
}
.siteBackTop[hidden] { display: none; }
.siteBackTop:hover {
  filter: brightness(1.06);
  opacity: .96;
  box-shadow: 0 10px 24px rgba(21, 63, 43, .3), inset 0 1px 0 rgba(255, 255, 255, .25);
  transform: translateY(-2px);
}
.siteBackTop:active { transform: translateY(0); }
.siteBackTop:focus-visible { outline: 3px solid rgba(42, 151, 87, .35); outline-offset: 3px; }
.siteBackTopIcon { width: 20px; height: 20px; }

@media (max-width: 700px) {
  .siteFooter { margin-top: 32px; padding: 24px 14px; }
  .siteFooterInner {
    grid-template-columns: 1fr;
    gap: 18px;
    text-align: center;
  }
  .siteFooterBrand img { margin: 0 auto; }
  .siteFooterLegal { order: 3; }
  .siteFooterFollow { justify-content: center; }
  .siteBackTop { right: 14px; bottom: 16px; width: 38px; height: 38px; }
}

@media (prefers-reduced-motion: reduce) {
  .siteBackTop { transition: none; }
}