.page-about {
  --about-rail-w: 190px;
  --about-gap: clamp(22px, 3.2vw, 46px);
  background: var(--ink);
  color: var(--mist);
  overflow-x: hidden;
}

.page-about .container {
  width: 100%;
  max-width: var(--w-max);
  margin-inline: auto;
  padding-inline: clamp(18px, 4vw, 44px);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding: clamp(22px, 4.4vw, 40px) 0 clamp(30px, 5vw, 52px);
  background: linear-gradient(180deg, var(--grass-deep) 0%, var(--ink) 100%);
  border-bottom: 1px solid var(--hair);
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: 3px;
  background: linear-gradient(90deg, var(--signal) 0 10%, var(--lime) 10% 21%, transparent 21%);
}

.page-about .breadcrumb {
  margin-bottom: 20px;
  font-size: 0.8rem;
  letter-spacing: 0.02em;
}

.page-about .breadcrumb ol {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0;
  padding: 0;
  list-style: none;
}

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

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

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

.page-about .breadcrumb [aria-current="page"] {
  color: var(--white);
}

.page-about .eyebrow {
  display: block;
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: 0.74rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--lime);
}

.page-about .about-hero__title {
  margin: 0;
  max-width: 20ch;
  font-family: var(--font-cn);
  font-weight: 800;
  font-size: clamp(2.05rem, 6.4vw, 4rem);
  line-height: 1.06;
  letter-spacing: -0.02em;
  color: var(--white);
}

.page-about .about-hero__lead {
  margin: 20px 0 0;
  max-width: 62ch;
  font-size: clamp(0.96rem, 1.6vw, 1.06rem);
  line-height: 1.75;
  color: var(--mist);
}

.page-about .about-hero__stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: clamp(26px, 4vw, 38px) 0 0;
  padding: 0;
  list-style: none;
  background: var(--hair);
  border: 1px solid var(--hair);
}

.page-about .about-stat {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 16px 16px 18px;
  background: var(--ink);
  min-width: 0;
}

.page-about .about-stat__num {
  font-family: var(--font-mono);
  font-size: clamp(1.45rem, 3.4vw, 2.05rem);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.01em;
  color: var(--lime);
}

.page-about .about-stat__label {
  font-size: 0.8rem;
  line-height: 1.5;
  color: var(--mist);
}

/* ---------- 横幅图 ---------- */
.page-about .about-banner {
  margin: 0;
  border-bottom: 1px solid var(--hair);
  background: var(--grass-deep);
}

.page-about .about-banner .media__img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
}

.page-about .media__cap {
  display: block;
  padding: 12px clamp(18px, 4vw, 44px);
  font-size: 0.78rem;
  line-height: 1.6;
  color: var(--mist);
  background: var(--grass-deep);
  border-top: 1px solid var(--hair);
}

/* ---------- 主体框架与索引刻度 ---------- */
.page-about .about-frame {
  padding-top: clamp(24px, 4vw, 44px);
}

.page-about .about-rail {
  position: relative;
  margin-bottom: 26px;
  background: var(--grass-deep);
  border-top: 1px solid var(--hair);
  border-bottom: 1px solid var(--hair);
  overflow-x: auto;
  scrollbar-width: none;
  -webkit-overflow-scrolling: touch;
}

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

.page-about .about-rail__list {
  display: flex;
  align-items: center;
  gap: 6px;
  margin: 0;
  padding: 10px 14px;
  list-style: none;
}

.page-about .about-rail__item {
  flex: 0 0 auto;
}

.page-about .about-rail__link {
  display: inline-flex;
  align-items: baseline;
  gap: 7px;
  padding: 7px 11px;
  border: 1px solid var(--hair);
  color: var(--mist);
  text-decoration: none;
  white-space: nowrap;
  font-size: 0.82rem;
  transition: color var(--t-fast) var(--ease), border-color var(--t-fast) var(--ease), background-color var(--t-fast) var(--ease);
}

.page-about .about-rail__link:hover,
.page-about .about-rail__link:focus-visible {
  color: var(--lime);
  border-color: var(--lime);
  background: rgba(201, 242, 78, 0.06);
}

.page-about .about-rail__num {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.08em;
  color: var(--lime);
}

/* ---------- 章节通用 ---------- */
.page-about .about-sec {
  padding: clamp(32px, 5vw, 56px) 0;
  scroll-margin-top: 140px;
}

.page-about .about-sec--paper,
.page-about .about-sec--grass,
.page-about .about-sec--deep {
  padding-inline: clamp(18px, 3.2vw, 40px);
}

.page-about .about-sec--paper {
  background: var(--paper);
  color: var(--on-paper);
}

.page-about .about-sec--grass {
  background: var(--grass);
  color: var(--mist);
}

.page-about .about-sec--deep {
  background: var(--grass-deep);
  color: var(--mist);
}

.page-about .about-sec__head {
  margin-bottom: clamp(18px, 2.6vw, 28px);
}

.page-about .about-sec__title {
  margin: 0;
  max-width: 26ch;
  font-family: var(--font-cn);
  font-weight: 800;
  font-size: clamp(1.5rem, 3.6vw, 2.2rem);
  line-height: 1.22;
  letter-spacing: -0.015em;
  color: var(--white);
}

.page-about .about-sec--paper .about-sec__title {
  color: #15201a;
}

.page-about .about-sec--paper .eyebrow {
  color: #a2461f;
}

.page-about .about-sec--grass .about-sec__title,
.page-about .about-sec--deep .about-sec__title {
  color: var(--white);
}

.page-about .about-sec__body > p {
  margin: 0 0 16px;
  max-width: 66ch;
  font-size: 0.98rem;
  line-height: 1.78;
}

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

.page-about .about-sec--paper .about-sec__body > p {
  color: var(--on-paper);
}

.page-about .about-sec__lead {
  font-size: 1.04rem !important;
  color: var(--on-paper-soft);
}

/* ---------- 版本刻度尺 ---------- */
.page-about .about-vers {
  position: relative;
  display: grid;
  gap: 0;
  margin: 28px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-vers::before {
  content: "";
  position: absolute;
  left: 6px;
  top: 8px;
  bottom: 8px;
  width: 1px;
  background: var(--hair-strong);
}

.page-about .about-ver {
  position: relative;
  padding: 0 0 24px 30px;
}

.page-about .about-ver:last-child {
  padding-bottom: 0;
}

.page-about .about-ver__mark {
  position: absolute;
  left: 1px;
  top: 5px;
  width: 11px;
  height: 11px;
  border-radius: 50%;
  background: var(--signal);
}

.page-about .about-ver__code {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.1em;
  color: #7a4a22;
}

.page-about .about-ver__name {
  margin: 4px 0 8px;
  font-family: var(--font-cn);
  font-weight: 800;
  font-size: 1.06rem;
  line-height: 1.35;
  letter-spacing: -0.01em;
  color: #15201a;
}

.page-about .about-ver__desc {
  margin: 0;
  max-width: 52ch;
  font-size: 0.9rem;
  line-height: 1.7;
  color: var(--on-paper-soft);
}

.page-about .about-vers__note {
  margin: 26px 0 0;
  padding-top: 16px;
  border-top: 1px solid rgba(38, 48, 42, 0.18);
  max-width: 66ch;
  font-size: 0.9rem;
  line-height: 1.72;
  color: var(--on-paper-soft);
}

/* ---------- 内容线 ---------- */
.page-about .about-lines__layout {
  display: grid;
  gap: 22px;
  margin-bottom: 30px;
}

.page-about .about-lines__text p {
  margin: 0 0 14px;
  max-width: 60ch;
  font-size: 0.96rem;
  line-height: 1.78;
}

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

.page-about .about-sidefig {
  margin: 0;
  border: 1px solid var(--hair);
}

.page-about .about-sidefig .media__img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
}

.page-about .about-sidefig .media__cap {
  background: rgba(8, 32, 25, 0.7);
  border-top: 1px solid var(--hair);
  padding: 10px 14px;
}

.page-about .about-lines {
  display: grid;
  gap: 0;
  margin: 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--hair);
}

.page-about .about-line {
  padding: 16px 0;
  border-bottom: 1px solid var(--hair);
}

.page-about .about-line__name {
  margin: 0 0 6px;
  font-family: var(--font-cn);
  font-weight: 700;
  font-size: 0.98rem;
  line-height: 1.35;
  letter-spacing: -0.005em;
  color: var(--lime);
}

.page-about .about-line__desc {
  margin: 0;
  font-size: 0.86rem;
  line-height: 1.7;
  color: var(--mist);
}

/* ---------- 目录与归档 ---------- */
.page-about .about-archive__grid {
  display: grid;
  gap: 26px;
  margin-top: 24px;
}

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

.page-about .about-tree {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
}

.page-about .about-tree__l1 {
  fill: none;
  stroke: rgba(38, 48, 42, 0.4);
  stroke-width: 1;
}

.page-about .about-tree__l2 {
  fill: rgba(18, 58, 46, 0.07);
  stroke: rgba(38, 48, 42, 0.45);
  stroke-width: 1;
}

.page-about .about-tree__l3 {
  fill: rgba(255, 90, 43, 0.1);
  stroke: rgba(210, 60, 25, 0.5);
  stroke-width: 1;
}

.page-about .about-tree text {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.02em;
  fill: var(--on-paper);
}

.page-about .about-tree__t1 {
  font-weight: 700;
}

.page-about .about-layer {
  border-top: 1px solid rgba(38, 48, 42, 0.22);
}

.page-about .about-layer:last-of-type {
  border-bottom: 1px solid rgba(38, 48, 42, 0.22);
}

.page-about .about-layer__sum {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 14px 0;
  cursor: pointer;
  font-family: var(--font-cn);
  font-weight: 700;
  font-size: 0.98rem;
  color: #15201a;
  list-style: none;
}

.page-about .about-layer__sum::-webkit-details-marker {
  display: none;
}

.page-about .about-layer__sum::before {
  content: "+";
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: 0.9rem;
  line-height: 1;
  color: var(--signal);
}

.page-about .about-layer[open] > .about-layer__sum::before {
  content: "−";
}

.page-about .about-layer__body {
  padding: 0 0 16px 22px;
}

.page-about .about-layer__body p {
  margin: 0;
  max-width: 58ch;
  font-size: 0.9rem;
  line-height: 1.75;
  color: var(--on-paper-soft);
}

.page-about .about-layers__note {
  margin: 20px 0 0;
  padding-left: 22px;
  font-size: 0.86rem;
  line-height: 1.72;
  color: var(--on-paper-soft);
}

/* ---------- 数据合作 ---------- */
.page-about .about-partners {
  display: grid;
  gap: 0;
  margin: 24px 0 20px;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--hair);
}

.page-about .about-partner {
  padding: 18px 0;
  border-bottom: 1px solid var(--hair);
}

.page-about .about-partner__name {
  margin: 10px 0 6px;
  font-family: var(--font-cn);
  font-weight: 700;
  font-size: 1rem;
  line-height: 1.35;
  color: var(--white);
}

.page-about .about-partner__desc {
  margin: 0;
  max-width: 52ch;
  font-size: 0.88rem;
  line-height: 1.72;
  color: var(--mist);
}

.page-about .tag {
  display: inline-block;
  padding: 4px 9px;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.1em;
  border: 1px solid currentColor;
}

.page-about .tag--lime {
  color: var(--lime);
}

.page-about .tag--signal {
  color: var(--signal);
}

/* ---------- 指定地区与联络 ---------- */
.page-about .about-region {
  display: grid;
  gap: 1px;
  margin: 22px 0 0;
  padding: 0;
  background: var(--hair);
  border: 1px solid var(--hair);
}

.page-about .about-region__item {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 14px 16px;
  background: var(--ink);
}

.page-about .about-region__key {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.1em;
  color: var(--lime);
}

.page-about .about-region__val {
  margin: 0;
  font-size: 0.94rem;
  line-height: 1.6;
  color: var(--white);
  word-break: break-word;
}

.page-about .about-region__val a {
  color: var(--white);
  text-decoration: none;
  border-bottom: 1px solid var(--hair-strong);
}

.page-about .about-region__val a:hover,
.page-about .about-region__val a:focus-visible {
  color: var(--lime);
  border-bottom-color: var(--lime);
}

.page-about .about-region__more {
  margin-top: 20px !important;
}

.page-about .about-region__more a {
  color: var(--lime);
  text-decoration: none;
  border-bottom: 1px solid rgba(201, 242, 78, 0.4);
}

.page-about .about-region__more a:hover,
.page-about .about-region__more a:focus-visible {
  border-bottom-color: var(--lime);
}

/* ---------- 结尾去向 ---------- */
.page-about .about-next {
  padding: clamp(30px, 5vw, 52px) 0 clamp(40px, 6vw, 64px);
  background: var(--grass-deep);
  border-top: 1px solid var(--hair);
}

.page-about .about-next__title {
  margin: 0 0 22px;
  font-family: var(--font-cn);
  font-weight: 800;
  font-size: clamp(1.3rem, 3vw, 1.7rem);
  letter-spacing: -0.01em;
  color: var(--white);
}

.page-about .about-next__list {
  display: grid;
  gap: 1px;
  margin: 0;
  padding: 0;
  list-style: none;
  background: var(--hair);
  border: 1px solid var(--hair);
}

.page-about .about-next__link {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 18px 16px;
  background: var(--grass-deep);
  color: var(--mist);
  text-decoration: none;
  transition: background-color var(--t-fast) var(--ease), color var(--t-fast) var(--ease);
}

.page-about .about-next__link:hover,
.page-about .about-next__link:focus-visible {
  background: rgba(201, 242, 78, 0.08);
  color: var(--white);
}

.page-about .about-next__label {
  display: flex;
  align-items: center;
  gap: 9px;
  font-family: var(--font-cn);
  font-weight: 700;
  font-size: 1rem;
  color: var(--white);
}

.page-about .about-next__label::before {
  content: "";
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--signal);
  flex: 0 0 auto;
}

.page-about .about-next__desc {
  font-size: 0.86rem;
  line-height: 1.7;
}

/* ---------- 宽屏 ---------- */
@media (min-width: 640px) {
  .page-about .about-hero__stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

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

@media (min-width: 820px) {
  .page-about .about-lines__layout {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    align-items: start;
    gap: clamp(22px, 3vw, 40px);
  }

  .page-about .about-lines {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    column-gap: 22px;
  }

  .page-about .about-archive__grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    align-items: start;
    gap: clamp(22px, 3vw, 42px);
  }

  .page-about .about-vers {
    grid-template-columns: repeat(5, minmax(0, 1fr));
    column-gap: 16px;
    margin-top: 32px;
  }

  .page-about .about-vers::before {
    left: 4px;
    right: 4px;
    top: 5px;
    bottom: auto;
    width: auto;
    height: 1px;
  }

  .page-about .about-ver {
    padding: 26px 0 0;
  }

  .page-about .about-ver__mark {
    top: 0;
    left: 0;
  }
}

@media (min-width: 1000px) {
  .page-about .about-frame {
    display: grid;
    grid-template-columns: var(--about-rail-w) minmax(0, 1fr);
    gap: var(--about-gap);
    align-items: start;
  }

  .page-about .about-rail {
    position: sticky;
    top: 118px;
    margin-bottom: 0;
    background: transparent;
    border: 1px solid var(--hair);
    border-left: 3px solid var(--signal);
    overflow: visible;
  }

  .page-about .about-rail__list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 10px 0;
  }

  .page-about .about-rail__item {
    position: relative;
  }

  .page-about .about-rail__item::before {
    content: "";
    position: absolute;
    left: 0;
    top: 50%;
    width: 5px;
    height: 5px;
    border-radius: 50%;
    background: var(--hair-strong);
    transform: translateY(-50%);
  }

  .page-about .about-rail__item:hover::before {
    background: var(--lime);
  }

  .page-about .about-rail__link {
    border-color: transparent;
    background: transparent;
    padding: 11px 14px 11px 20px;
  }

  .page-about .about-rail__link:hover,
  .page-about .about-rail__link:focus-visible {
    border-color: transparent;
    background: rgba(201, 242, 78, 0.07);
  }

  .page-about .about-sec {
    padding-block: clamp(38px, 4vw, 60px);
  }

  .page-about .about-lines {
    grid-template-columns: repeat(6, minmax(0, 1fr));
    column-gap: 18px;
  }

  .page-about .about-line__name {
    font-size: 0.92rem;
  }

  .page-about .about-line__desc {
    font-size: 0.81rem;
  }

  .page-about .about-partners {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    column-gap: 26px;
    border-top: 1px solid var(--hair);
  }

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

@media (min-width: 1240px) {
  .page-about .about-archive__grid {
    grid-template-columns: minmax(0, 6fr) minmax(0, 6fr);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-rail__link,
  .page-about .about-next__link {
    transition: none;
  }
}
<<<END>>>