.page-about {
  --about-toc-h: 52px;
}

.page-about .about-crumbs {
  padding-top: calc(var(--header-h) + 18px);
}

.page-about .breadcrumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-size: 14px;
  color: var(--ink-2);
}

.page-about .breadcrumbs__link {
  color: var(--ink-2);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color .2s var(--ease), border-color .2s var(--ease);
}

.page-about .breadcrumbs__link:hover,
.page-about .breadcrumbs__link:focus-visible {
  color: var(--cold);
  border-color: var(--cold);
}

.page-about .breadcrumbs__sep {
  color: var(--line);
}

.page-about .breadcrumbs__current {
  color: var(--ink);
}

/* ---------- 首屏 ---------- */

.page-about .about-hero {
  position: relative;
  padding: clamp(26px, 5vw, 56px) 0 clamp(34px, 5vw, 64px);
  overflow: hidden;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: -30% 45% 10% -25%;
  background: radial-gradient(circle at 34% 36%, rgba(47, 224, 240, .15), transparent 64%);
  pointer-events: none;
}

.page-about .about-hero__grid {
  position: relative;
  display: grid;
  gap: 30px;
}

.page-about .about-hero__title {
  margin: 14px 0 0;
  font-size: clamp(30px, 6.4vw, 56px);
  line-height: 1.12;
  letter-spacing: -.02em;
}

.page-about .about-hero__lede {
  margin: 18px 0 0;
  max-width: 46ch;
  font-size: clamp(16px, 1.5vw, 19px);
  line-height: 1.85;
  color: var(--ink-2);
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 26px;
}

.page-about .about-hero__facts {
  border: 1px solid var(--line);
  border-radius: var(--r-md);
  background: linear-gradient(162deg, rgba(22, 35, 61, .88), rgba(11, 19, 38, .94));
  box-shadow: inset 0 1px 0 rgba(143, 244, 255, .1);
  padding: 20px;
}

.page-about .about-hero__facts-title {
  margin: 0;
  font-size: 12px;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--cold);
}

.page-about .about-facts {
  list-style: none;
  margin: 16px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
}

.page-about .about-fact {
  display: grid;
  gap: 5px;
  padding: 12px;
  border: 1px solid rgba(42, 58, 92, .8);
  border-radius: var(--r-sm);
  background: rgba(5, 10, 24, .55);
}

.page-about .about-fact__num {
  font-size: clamp(20px, 3.4vw, 26px);
  font-weight: 700;
  letter-spacing: -.01em;
  color: var(--cold);
}

.page-about .about-fact:nth-child(even) .about-fact__num {
  color: var(--hot-2);
}

.page-about .about-fact__label {
  font-size: 13px;
  line-height: 1.6;
  color: var(--ink-2);
}

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.5fr) minmax(0, 1fr);
    align-items: end;
    gap: 56px;
  }
}

/* ---------- 章节导航 ---------- */

.page-about .about-toc {
  position: sticky;
  top: var(--header-h);
  z-index: 6;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  background: rgba(5, 10, 24, .9);
  backdrop-filter: blur(12px);
}

.page-about .about-toc__list {
  list-style: none;
  margin: 0;
  padding: 11px 0;
  display: flex;
  gap: 8px;
  overflow-x: auto;
  scrollbar-width: none;
  -webkit-overflow-scrolling: touch;
}

.page-about .about-toc__list::-webkit-scrollbar {
  display: none;
}

.page-about .about-toc__link {
  flex: 0 0 auto;
  display: inline-block;
  padding: 7px 15px;
  border-radius: 999px;
  border: 1px solid var(--line);
  color: var(--ink-2);
  font-size: 14px;
  white-space: nowrap;
  text-decoration: none;
  transition: color .22s var(--ease), border-color .22s var(--ease), background .22s var(--ease);
}

.page-about .about-toc__link:hover,
.page-about .about-toc__link:focus-visible {
  color: var(--ink);
  border-color: var(--cold);
}

.page-about .about-toc__link.is-active {
  color: var(--bg);
  background: var(--cold);
  border-color: var(--cold);
  font-weight: 700;
}

/* ---------- 章节骨架 ---------- */

.page-about .chapter {
  padding: clamp(52px, 8vw, 104px) 0;
  border-top: 1px solid var(--line);
  scroll-margin-top: calc(var(--header-h) + 66px);
}

.page-about .chapter:first-of-type {
  border-top: 0;
}

.page-about .chapter__grid {
  display: grid;
  gap: 18px;
}

.page-about .chapter__num {
  display: block;
  font-size: 13px;
  letter-spacing: .18em;
  color: var(--cold);
  margin-bottom: 14px;
}

.page-about .chapter__num::after {
  content: "";
  display: inline-block;
  width: 44px;
  height: 1px;
  margin-left: 12px;
  vertical-align: middle;
  background: linear-gradient(90deg, var(--cold), transparent);
}

.page-about .chapter__title {
  margin: 0;
  max-width: 22ch;
}

.page-about .chapter__body p {
  margin: 0 0 16px;
  font-size: 17px;
  line-height: 1.9;
  color: var(--ink);
}

.page-about .chapter__body p:last-child {
  margin-bottom: 0;
}

.page-about .chapter__links {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 22px;
}

@media (min-width: 900px) {
  .page-about .chapter__grid {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 1fr);
    gap: 64px;
    align-items: start;
  }
}

/* ---------- 图片框 ---------- */

.page-about .about-figure {
  margin: 34px 0 0;
}

.page-about .about-figure img {
  max-width: 100%;
  height: auto;
  object-fit: cover;
}

/* ---------- 版本节点轴 ---------- */

.page-about .version-rail {
  list-style: none;
  margin: 30px 0 0;
  padding: 6px 0 18px;
  display: flex;
  gap: 14px;
  overflow-x: auto;
  scroll-snap-type: x mandatory;
  scrollbar-width: thin;
}

.page-about .version-node {
  position: relative;
  scroll-snap-align: start;
  flex: 1 0 235px;
  padding: 26px 18px 20px;
  border: 1px solid var(--line);
  border-radius: var(--r-md);
  background: linear-gradient(168deg, rgba(22, 35, 61, .72), rgba(11, 19, 38, .9));
  transition: transform .24s var(--ease), border-color .24s var(--ease);
}

.page-about .version-node::before {
  content: "";
  position: absolute;
  top: -1px;
  left: 20px;
  width: 46px;
  height: 3px;
  border-radius: 3px;
  background: var(--cold);
  box-shadow: 0 0 14px rgba(47, 224, 240, .55);
}

.page-about .version-node--hot::before {
  background: var(--hot);
  box-shadow: 0 0 14px rgba(255, 107, 44, .55);
}

.page-about .version-node:hover,
.page-about .version-node:focus-visible {
  transform: translateY(-4px);
  border-color: var(--cold);
  outline: none;
}

.page-about .version-node--hot:hover,
.page-about .version-node--hot:focus-visible {
  border-color: var(--hot);
}

.page-about .version-node__ver {
  display: inline-block;
  padding: 3px 11px;
  border-radius: 999px;
  border: 1px solid rgba(47, 224, 240, .35);
  background: rgba(47, 224, 240, .08);
  color: var(--cold);
  font-size: 13px;
  letter-spacing: .1em;
}

.page-about .version-node--hot .version-node__ver {
  border-color: rgba(255, 107, 44, .38);
  background: rgba(255, 107, 44, .09);
  color: var(--hot-2);
}

.page-about .version-node__title {
  margin: 14px 0 0;
  font-size: 19px;
}

.page-about .version-node__desc {
  margin: 10px 0 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--ink-2);
}

@media (min-width: 1000px) {
  .page-about .version-rail {
    display: grid;
    grid-template-columns: repeat(5, minmax(0, 1fr));
    gap: 14px;
    overflow: visible;
    padding-bottom: 0;
  }

  .page-about .version-node {
    flex: none;
  }
}

/* ---------- 团队构成 ---------- */

.page-about .team-layout {
  display: grid;
  gap: 24px;
  margin-top: 34px;
}

.page-about .team-layout .about-figure {
  margin: 0;
}

.page-about .team-bars {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 14px;
}

.page-about .team-bar {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  grid-template-areas:
    "label num"
    "track track"
    "desc desc";
  gap: 10px;
  padding: 16px;
  border: 1px solid var(--line);
  border-radius: var(--r-sm);
  background: rgba(11, 19, 38, .74);
  transition: border-color .24s var(--ease), background .24s var(--ease);
}

.page-about .team-bar:hover,
.page-about .team-bar:focus-within {
  border-color: var(--cold);
  background: rgba(22, 35, 61, .8);
}

.page-about .team-bar__label {
  grid-area: label;
  font-weight: 700;
  font-size: 16px;
  color: var(--ink);
}

.page-about .team-bar__num {
  grid-area: num;
  font-size: 24px;
  font-weight: 700;
  color: var(--cold);
  line-height: 1;
}

.page-about .team-bar__track {
  grid-area: track;
  height: 8px;
  border-radius: 999px;
  background: rgba(42, 58, 92, .62);
  overflow: hidden;
}

.page-about .team-bar__fill {
  display: block;
  height: 100%;
  border-radius: inherit;
  background: linear-gradient(90deg, var(--cold-2), var(--cold));
}

.page-about .team-bar:nth-child(1) .team-bar__fill { width: 100%; }
.page-about .team-bar:nth-child(2) .team-bar__fill { width: 63%; }
.page-about .team-bar:nth-child(3) .team-bar__fill { width: 82%; }

.page-about .team-bar:nth-child(2) .team-bar__num { color: var(--hot-2); }
.page-about .team-bar:nth-child(2) .team-bar__fill {
  background: linear-gradient(90deg, var(--hot-2), var(--hot));
}

.page-about .team-bar__desc {
  grid-area: desc;
  font-size: 14px;
  line-height: 1.7;
  color: var(--ink-2);
}

@media (min-width: 900px) {
  .page-about .team-layout {
    grid-template-columns: minmax(0, 1fr) minmax(0, .92fr);
    gap: 48px;
    align-items: start;
  }

  .page-about .team-bar__desc {
    position: absolute;
    top: calc(100% + 8px);
    left: 14px;
    right: 14px;
    z-index: 3;
    padding: 10px 13px;
    border: 1px solid var(--line);
    border-radius: var(--r-sm);
    background: var(--raise);
    color: var(--ink);
    font-size: 14px;
    opacity: 0;
    transform: translateY(6px);
    pointer-events: none;
    transition: opacity .22s var(--ease), transform .22s var(--ease);
  }

  .page-about .team-bar:hover .team-bar__desc,
  .page-about .team-bar:focus-within .team-bar__desc {
    opacity: 1;
    transform: translateY(0);
  }
}

/* ---------- 站点信息表 ---------- */

.page-about .site-facts {
  list-style: none;
  margin: 22px 0 0;
  padding: 0;
  display: grid;
  gap: 12px;
}

.page-about .site-facts li {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 12px;
  padding-bottom: 12px;
  border-bottom: 1px solid rgba(42, 58, 92, .55);
}

.page-about .site-facts li:last-child {
  border-bottom: 0;
  padding-bottom: 0;
}

.page-about .site-facts__key {
  flex: 0 0 76px;
  font-size: 13px;
  color: var(--ink-2);
}

.page-about .site-facts__val {
  font-size: 15px;
  color: var(--ink);
  word-break: break-word;
}

/* ---------- 收尾 ---------- */

.page-about .about-outro {
  border-top: 1px solid var(--line);
  padding: clamp(48px, 7vw, 88px) 0 clamp(64px, 9vw, 112px);
}

.page-about .about-outro__title {
  margin: 12px 0 0;
  max-width: 24ch;
}

.page-about .about-outro__links {
  display: grid;
  gap: 12px;
  margin-top: 28px;
}

.page-about .about-link {
  display: grid;
  gap: 6px;
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: var(--r-md);
  background: rgba(11, 19, 38, .62);
  color: var(--ink);
  font-weight: 700;
  font-size: 16px;
  text-decoration: none;
  transition: border-color .24s var(--ease), background .24s var(--ease), transform .24s var(--ease);
}

.page-about .about-link span {
  font-weight: 400;
  font-size: 14px;
  line-height: 1.65;
  color: var(--ink-2);
}

.page-about .about-link:hover,
.page-about .about-link:focus-visible {
  border-color: var(--cold);
  background: rgba(22, 35, 61, .86);
  transform: translateY(-3px);
}

@media (min-width: 720px) {
  .page-about .about-outro__links {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 1080px) {
  .page-about .about-outro__links {
    grid-template-columns: repeat(5, minmax(0, 1fr));
  }
}

@media (max-width: 420px) {
  .page-about .about-facts {
    grid-template-columns: minmax(0, 1fr);
  }

  .page-about .chapter__links .chip {
    flex: 1 1 100%;
    text-align: center;
  }
}