.page-about {
  --about-gap: clamp(20px, 3.4vw, 44px);
  --about-pad: clamp(30px, 5vw, 68px);
  --about-cyan-soft: rgba(47, 227, 210, 0.18);
  background: var(--ink-deep);
  color: var(--white);
  overflow-x: clip;
}

.page-about .breadcrumb {
  padding: 22px 0 4px;
}

.page-about .breadcrumb-list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin: 0;
  padding: 0;
  list-style: none;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
}

.page-about .breadcrumb-list > li + li::before {
  content: "/";
  margin-right: 8px;
  color: var(--line);
}

.page-about .breadcrumb-link {
  color: var(--steel);
  text-decoration: none;
}

.page-about .breadcrumb-link:hover,
.page-about .breadcrumb-link:focus-visible {
  color: var(--cyan);
}

.page-about .breadcrumb-current {
  color: var(--white);
}

/* ---------- 首屏 ---------- */

.page-about .about-hero {
  padding: clamp(20px, 3vw, 34px) 0 clamp(38px, 6vw, 76px);
  border-bottom: 1px solid var(--line);
}

.page-about .about-hero__inner {
  display: grid;
  gap: var(--about-gap);
  align-items: center;
}

.page-about .about-hero__intro .eyebrow {
  color: var(--cyan);
  margin: 0 0 14px;
}

.page-about .about-hero .display {
  margin: 0 0 18px;
  font-size: clamp(30px, 5.2vw, 58px);
  line-height: 1.16;
  letter-spacing: -0.02em;
  color: var(--white);
}

.page-about .about-hero .lede {
  margin: 0;
  max-width: 46em;
  font-size: clamp(15px, 1.6vw, 17px);
  line-height: 1.8;
  color: var(--steel);
}

.page-about .about-hero__facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px 18px;
  margin: 30px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-fact {
  border-top: 1px solid var(--line);
  padding-top: 10px;
}

.page-about .about-fact__num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(22px, 3vw, 30px);
  line-height: 1.1;
  color: var(--cyan);
}

.page-about .about-fact__label {
  display: block;
  margin-top: 5px;
  font-size: 13px;
  color: var(--steel);
}

.page-about .about-hero__media {
  margin: 0;
}

.page-about .about-hero__media img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 3 / 2;
  object-fit: cover;
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.page-about .media-caption {
  margin-top: 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  line-height: 1.7;
  color: var(--steel);
}

/* ---------- 章节索引 ---------- */

.page-about .about-index {
  position: sticky;
  top: 68px;
  z-index: 5;
  background: rgba(7, 19, 34, 0.94);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(6px);
}

.page-about .about-index__inner {
  display: flex;
  align-items: center;
  padding: 8px 0;
}

.page-about .about-index__list {
  display: flex;
  gap: 4px;
  margin: 0;
  padding: 0 0 2px;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: thin;
  -webkit-overflow-scrolling: touch;
}

.page-about .about-index__link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  min-height: 44px;
  padding: 0 12px;
  border: 1px solid transparent;
  border-radius: var(--radius);
  color: var(--steel);
  font-size: 13px;
  white-space: nowrap;
  text-decoration: none;
  transition: border-color var(--ease), color var(--ease);
}

.page-about .about-index__link .num {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--cyan);
}

.page-about .about-index__link:hover,
.page-about .about-index__link:focus-visible {
  border-color: var(--cyan);
  color: var(--white);
}

/* ---------- 章节骨架 ---------- */

.page-about .about-chapter {
  padding: var(--about-pad) 0;
  border-bottom: 1px solid var(--line-soft);
}

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

.page-about .chapter-rail {
  border-top: 1px solid var(--line);
  padding-top: 14px;
}

.page-about .chapter-num {
  display: block;
  margin-bottom: 10px;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.12em;
  color: var(--cyan);
}

.page-about .section-title {
  margin: 0;
  font-size: clamp(21px, 2.7vw, 30px);
  line-height: 1.36;
  color: var(--white);
}

.page-about .prose p {
  margin: 0 0 1em;
  font-size: 16px;
  line-height: 1.8;
  color: var(--white);
}

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

/* ---------- 要点与图片 ---------- */

.page-about .about-points {
  display: grid;
  gap: 10px;
  margin: 1.5em 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-points li {
  position: relative;
  border-top: 1px solid var(--line);
  padding: 11px 0 0 18px;
  font-size: 15px;
  line-height: 1.75;
  color: var(--steel);
}

.page-about .about-points li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 20px;
  width: 6px;
  height: 6px;
  background: var(--orange);
}

.page-about .about-figure {
  margin: 30px 0 0;
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 3 / 2;
  object-fit: cover;
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.page-about .about-figure--band {
  margin-top: 0;
}

/* ---------- 团队三线 ---------- */

.page-about .about-team {
  display: grid;
  gap: 14px;
  margin-top: 26px;
}

.page-about .about-team__item {
  padding: 20px;
  background: var(--deck);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  transition: border-color var(--ease);
}

.page-about .about-team__item:hover {
  border-color: var(--cyan);
}

.page-about .about-team__num {
  display: block;
  font-family: var(--font-mono);
  font-size: 30px;
  line-height: 1.1;
  color: var(--orange);
}

.page-about .about-team__item .card-title {
  margin: 8px 0 8px;
  font-size: 16px;
  color: var(--white);
}

.page-about .about-team__item .card-body {
  margin: 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--steel);
}

/* ---------- 时间线 ---------- */

.page-about .about-timeline {
  display: grid;
  margin: 26px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-node {
  position: relative;
  border-left: 1px solid var(--line);
  padding: 14px 0 18px 20px;
}

.page-about .about-node::before {
  content: "";
  position: absolute;
  left: -4.5px;
  top: 20px;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--signal);
}

.page-about .about-node--current::before {
  background: var(--cyan);
  box-shadow: 0 0 0 3px var(--about-cyan-soft);
}

.page-about .about-node__season {
  display: block;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--cyan);
}

.page-about .about-node__title {
  margin: 7px 0 6px;
  font-size: 15px;
  color: var(--white);
}

.page-about .about-node__desc {
  margin: 0;
  font-size: 13px;
  line-height: 1.75;
  color: var(--steel);
  transition: color var(--ease);
}

/* ---------- 覆盖数据 ---------- */

.page-about .about-stat-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
  margin: 24px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-stat {
  padding: 16px;
  background: var(--deck);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  transition: border-color var(--ease);
}

.page-about .about-stat:hover {
  border-color: var(--orange);
}

.page-about .about-stat__value {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(20px, 2.4vw, 26px);
  line-height: 1.15;
  color: var(--white);
}

.page-about .about-stat__label {
  display: block;
  margin-top: 7px;
  font-size: 13px;
  line-height: 1.65;
  color: var(--steel);
}

/* ---------- 三条线 ---------- */

.page-about .about-pledges {
  display: grid;
  gap: 18px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-pledge {
  border-top: 1px solid var(--line);
  padding-top: 14px;
}

.page-about .about-pledge__num {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--orange);
}

.page-about .about-pledge__title {
  margin: 8px 0 8px;
  font-size: 17px;
  color: var(--white);
}

.page-about .about-pledge__text {
  margin: 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--steel);
}

/* ---------- 结尾入口 ---------- */

.page-about .about-cta {
  padding: var(--about-pad) 0 calc(var(--about-pad) + 14px);
}

.page-about .about-cta .section-head {
  border-top: 1px solid var(--line);
  padding-top: 16px;
}

.page-about .about-cta__grid {
  display: grid;
  gap: 12px;
  margin-top: 24px;
}

.page-about .about-cta__link {
  display: block;
  min-height: 44px;
  padding: 16px;
  background: var(--deck);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  text-decoration: none;
  transition: border-color var(--ease), background var(--ease);
}

.page-about .about-cta__link:hover,
.page-about .about-cta__link:focus-visible {
  border-color: var(--cyan);
  background: var(--about-cyan-soft);
}

.page-about .about-cta__link .eyebrow {
  display: block;
  margin-bottom: 8px;
  color: var(--cyan);
}

.page-about .about-cta__text {
  display: block;
  font-size: 14px;
  line-height: 1.65;
  color: var(--white);
}

/* ---------- 响应式 ---------- */

@media (min-width: 700px) {
  .page-about .about-hero__facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .about-team {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .about-stat-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .about-cta__grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 900px) {
  .page-about .about-index {
    top: 74px;
  }

  .page-about .about-hero__inner {
    grid-template-columns: 34fr 66fr;
  }

  .page-about .chapter-grid {
    grid-template-columns: 34fr 66fr;
    gap: var(--about-gap);
  }

  .page-about .chapter-rail {
    position: sticky;
    top: 148px;
    align-self: start;
  }

  .page-about .about-node {
    border-left: 0;
    border-top: 1px solid var(--line);
    padding: 22px 16px 0 0;
  }

  .page-about .about-node::before {
    left: 0;
    top: -4.5px;
  }

  .page-about .about-timeline {
    grid-template-columns: repeat(6, minmax(0, 1fr));
  }

  .page-about .about-node:hover {
    border-top-color: var(--cyan);
  }

  .page-about .about-node:hover .about-node__desc {
    color: var(--white);
  }

  .page-about .about-pledges {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 24px;
  }
}

@media (min-width: 1024px) {
  .page-about .about-cta__grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-index__link,
  .page-about .about-team__item,
  .page-about .about-stat,
  .page-about .about-node__desc,
  .page-about .about-cta__link {
    transition: none;
  }
}