/* ===== 关于九洲 · 页面专属样式（作用域 .page-about） ===== */

.page-about {
  display: block;
  max-width: 1360px;
  margin-inline: auto;
  padding: clamp(1.5rem, 4vw, 3rem) var(--gutter) clamp(4rem, 9vw, 6.5rem);
  background: var(--moon);
  color: var(--ink);
  font-family: var(--font-body);
}

/* ---------- 首屏 ---------- */

.page-about .about-hero {
  padding-bottom: clamp(2rem, 5vw, 3.5rem);
  border-bottom: 1px solid var(--ink-line);
}

.page-about .about-crumbs__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  margin: 0 0 clamp(1.5rem, 4vw, 2.5rem);
  padding: 0;
  list-style: none;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: .06em;
  color: var(--ink-soft);
}

.page-about .about-crumbs__item {
  display: inline-flex;
  align-items: center;
}

.page-about .about-crumbs__item + .about-crumbs__item::before {
  content: "/";
  margin: 0 .55rem;
  color: var(--mist);
}

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

.page-about .about-crumbs__item a:hover {
  color: var(--cinnabar-deep);
  border-bottom-color: var(--cinnabar-deep);
}

.page-about .about-hero__eyebrow {
  margin: 0 0 .85rem;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: .14em;
  color: var(--ochre);
}

.page-about .about-hero__title {
  max-width: 17em;
  margin: 0 0 1.25rem;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(2.125rem, 7.4vw, 4.25rem);
  line-height: 1.05;
  letter-spacing: -0.01em;
  color: var(--ink);
}

.page-about .about-hero__lead {
  max-width: 34em;
  margin: 0;
  font-size: var(--fs-17);
  line-height: 1.9;
  color: var(--ink-soft);
}

/* ---------- 左栏 + 右栏外壳 ---------- */

.page-about .about-shell {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(1.75rem, 4vw, 3rem);
  padding-top: clamp(2rem, 5vw, 3.5rem);
}

.page-about .about-shell > * {
  min-width: 0;
}

.page-about .about-body {
  min-width: 0;
}

/* ---------- 左侧纵向时间轴 ---------- */

.page-about .about-rail {
  padding-bottom: 1rem;
  border-bottom: 1px solid var(--ink-line);
}

.page-about .about-rail__title {
  margin: 0 0 .8rem;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: .14em;
  color: var(--ink-soft);
}

.page-about .rail {
  display: flex;
  gap: 1.35rem;
  margin: 0;
  padding: 0 0 .5rem;
  list-style: none;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: thin;
}

.page-about .rail__item {
  flex: none;
}

.page-about .rail__link {
  display: inline-flex;
  align-items: center;
  gap: .5rem;
  padding: .3rem 0;
  white-space: nowrap;
  color: var(--ink-soft);
  text-decoration: none;
  font-family: var(--font-mono);
  font-size: var(--fs-13);
  letter-spacing: .06em;
  transition: color .2s var(--ease);
}

.page-about .rail__node {
  flex: none;
  width: 8px;
  height: 8px;
  background: var(--ochre);
  transition: background-color .2s var(--ease), transform .2s var(--ease);
}

.page-about .rail__num {
  font-size: var(--fs-12);
  color: var(--ink-soft);
  transition: color .2s var(--ease);
}

.page-about .rail__label {
  font-family: var(--font-body);
  font-size: var(--fs-13);
  letter-spacing: .02em;
}

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

.page-about .rail__link:hover .rail__node,
.page-about .rail__link:focus-visible .rail__node {
  background: var(--cinnabar);
  transform: scale(1.35);
}

.page-about .rail__link:hover .rail__num,
.page-about .rail__link:focus-visible .rail__num {
  color: var(--cinnabar-deep);
}

/* ---------- 内容区通用 ---------- */

.page-about .sec {
  padding: clamp(2.25rem, 5.5vw, 4rem) 0;
  border-top: 1px solid var(--ink-line);
  scroll-margin-top: calc(var(--header-h) + 1.5rem);
}

.page-about .sec:first-child {
  border-top: 0;
  padding-top: 0;
}

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

.page-about .sec__title {
  margin: 0 0 1.1rem;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(1.625rem, 4.4vw, var(--fs-34));
  line-height: 1.12;
  letter-spacing: -0.01em;
  color: var(--ink);
}

.page-about .sec__title::before {
  content: "";
  display: block;
  width: 28px;
  height: 3px;
  margin-bottom: .9rem;
  background: var(--ochre);
}

.page-about .sec__lead {
  max-width: 34em;
  margin: 0 0 1.5rem;
  font-size: var(--fs-17);
  line-height: 1.9;
  color: var(--ink-soft);
}

.page-about .sec__body p {
  max-width: 34em;
  margin: 0 0 1.2em;
  font-size: var(--fs-17);
  line-height: 1.9;
  color: var(--ink-soft);
}

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

.page-about .sec__more {
  margin: 1.75rem 0 0;
  font-family: var(--font-mono);
  font-size: var(--fs-13);
  letter-spacing: .06em;
  color: var(--ink-soft);
}

.page-about .sec a {
  color: var(--cinnabar-deep);
  text-decoration: none;
  border-bottom: 1px solid rgba(178, 58, 24, .35);
  transition: color .2s var(--ease), border-color .2s var(--ease);
}

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

/* ---------- 图片框 ---------- */

.page-about .about-figure {
  margin: 0 0 clamp(1.75rem, 4vw, 2.5rem);
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  border: 1px solid var(--ink-line);
  border-radius: var(--radius);
  background-color: var(--mist);
  object-fit: cover;
}

.page-about .about-figure figcaption {
  margin-top: .7rem;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: .06em;
  color: var(--ink-soft);
}

/* ---------- 发展历程时间轴 ---------- */

.page-about .timeline {
  position: relative;
  margin: 0;
  padding: 0 0 0 1.75rem;
  list-style: none;
}

.page-about .timeline::before {
  content: "";
  position: absolute;
  left: 4px;
  top: .7rem;
  bottom: .9rem;
  width: 1px;
  background: var(--ink-line-strong);
}

.page-about .timeline__item {
  position: relative;
  padding-bottom: clamp(1.6rem, 3.5vw, 2.35rem);
}

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

.page-about .timeline__node {
  position: absolute;
  left: -1.75rem;
  top: .6rem;
  width: 9px;
  height: 9px;
  background: var(--ochre);
  transition: background-color .2s var(--ease), transform .2s var(--ease);
}

.page-about .timeline__item:hover .timeline__node {
  background: var(--cinnabar);
  transform: scale(1.35);
}

.page-about .timeline__year {
  margin: 0 0 .3rem;
  font-family: var(--font-mono);
  font-size: var(--fs-13);
  letter-spacing: .1em;
  color: var(--ochre);
}

.page-about .timeline__title {
  margin: 0 0 .45rem;
  font-family: var(--font-display);
  font-size: var(--fs-22);
  font-weight: 800;
  line-height: 1.3;
  color: var(--ink);
}

.page-about .timeline__text {
  max-width: 34em;
  margin: 0;
  font-size: var(--fs-17);
  line-height: 1.9;
  color: var(--ink-soft);
}

/* ---------- 折叠面板 ---------- */

.page-about .gates {
  margin: clamp(1.5rem, 3.5vw, 2rem) 0 0;
  border-bottom: 1px solid var(--ink-line);
}

.page-about .gate {
  border-top: 1px solid var(--ink-line);
  background: var(--paper);
}

.page-about .gate__summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 1rem 1.15rem;
  cursor: pointer;
  list-style: none;
  font-family: var(--font-display);
  font-size: var(--fs-17);
  font-weight: 700;
  color: var(--ink);
  transition: background-color .2s var(--ease);
}

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

.page-about .gate__summary::after {
  content: "+";
  flex: none;
  font-family: var(--font-mono);
  font-size: var(--fs-17);
  line-height: 1;
  color: var(--cinnabar-deep);
}

.page-about .gate[open] > .gate__summary::after {
  content: "−";
}

.page-about .gate__summary:hover {
  background: rgba(16, 20, 24, .035);
}

.page-about .gate__summary:focus-visible {
  outline: 2px solid var(--cinnabar);
  outline-offset: -2px;
}

.page-about .gate__body {
  padding: 0 1.15rem 1.15rem;
}

.page-about .gate__body p {
  max-width: 34em;
  margin: 0;
  font-size: var(--fs-17);
  line-height: 1.9;
  color: var(--ink-soft);
}

/* ---------- 团队分工 ---------- */

.page-about .team-list {
  display: grid;
  gap: 1.5rem;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .team-item {
  padding: 1.35rem 1.4rem 1.5rem;
  background: var(--paper);
  border: 1px solid var(--ink-line);
  border-left: 3px solid var(--ochre);
  border-radius: var(--radius);
  transition: transform .2s var(--ease), box-shadow .2s var(--ease);
}

.page-about .team-item:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-1);
}

.page-about .team-item__count {
  margin: 0 0 .35rem;
  font-family: var(--font-mono);
  font-size: var(--fs-13);
  letter-spacing: .08em;
  color: var(--ochre);
}

.page-about .team-item__num {
  font-size: var(--fs-22);
  font-weight: 700;
  color: var(--dai);
}

.page-about .team-item__title {
  margin: 0 0 .55rem;
  font-family: var(--font-display);
  font-size: var(--fs-17);
  font-weight: 800;
  line-height: 1.45;
  color: var(--ink);
}

.page-about .team-item__text {
  margin: 0;
  font-size: var(--fs-13);
  line-height: 1.85;
  color: var(--ink-soft);
}

/* ---------- 合作伙伴 ---------- */

.page-about .partner-list {
  display: grid;
  gap: 1.4rem;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .partner-item {
  padding-top: 1rem;
  border-top: 2px solid var(--dai);
}

.page-about .partner-item__title {
  margin: 0 0 .45rem;
  font-family: var(--font-display);
  font-size: var(--fs-17);
  font-weight: 800;
  color: var(--ink);
}

.page-about .partner-item__text {
  margin: 0;
  font-size: var(--fs-13);
  line-height: 1.85;
  color: var(--ink-soft);
}

/* ---------- 使用面貌刻度尺 ---------- */

.page-about .scale-list {
  display: grid;
  gap: 1.4rem;
  margin: 0 0 clamp(1.5rem, 4vw, 2rem);
  padding: 0;
  list-style: none;
}

.page-about .scale-item {
  padding-bottom: .95rem;
  border-bottom: 1px solid var(--ink-line);
}

.page-about .scale-item__value {
  display: block;
  margin: 0 0 .2rem;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(1.625rem, 4.4vw, var(--fs-34));
  line-height: 1.05;
  letter-spacing: -0.01em;
  color: var(--dai);
}

.page-about .scale-item__label {
  margin: 0;
  font-size: var(--fs-13);
  line-height: 1.75;
  color: var(--ink-soft);
}

.page-about .scale-item__bar {
  display: block;
  position: relative;
  height: 3px;
  margin-top: .85rem;
  background: var(--ink-line);
}

.page-about .scale-item__bar::after {
  content: "";
  position: absolute;
  top: 0;
  bottom: 0;
  left: 0;
  width: 50%;
  background: var(--cinnabar);
}

.page-about .scale-item:nth-child(1) .scale-item__bar::after { width: 100%; }
.page-about .scale-item:nth-child(2) .scale-item__bar::after { width: 42%; }
.page-about .scale-item:nth-child(3) .scale-item__bar::after { width: 74%; }
.page-about .scale-item:nth-child(4) .scale-item__bar::after { width: 58%; }

/* ---------- 长期做法 ---------- */

.page-about .principles {
  counter-reset: principle;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .principle {
  counter-increment: principle;
  position: relative;
  padding: 1.4rem 0 1.4rem 3rem;
  border-top: 1px solid var(--ink-line);
}

.page-about .principle:last-child {
  border-bottom: 1px solid var(--ink-line);
}

.page-about .principle::before {
  content: "0" counter(principle);
  position: absolute;
  left: 0;
  top: 1.45rem;
  font-family: var(--font-mono);
  font-size: var(--fs-13);
  letter-spacing: .1em;
  color: var(--ochre);
}

.page-about .principle__title {
  margin: 0 0 .45rem;
  font-family: var(--font-display);
  font-size: var(--fs-17);
  font-weight: 800;
  line-height: 1.45;
  color: var(--ink);
}

.page-about .principle__text {
  max-width: 34em;
  margin: 0;
  font-size: var(--fs-17);
  line-height: 1.9;
  color: var(--ink-soft);
}

/* ---------- 窄屏适配 ---------- */

@media (max-width: 599px) {
  .page-about .about-hero__title {
    font-size: clamp(1.875rem, 9vw, 2.5rem);
  }

  .page-about .sec__title {
    font-size: 1.5rem;
  }

  .page-about .principle {
    padding-left: 2.25rem;
  }

  .page-about .timeline {
    padding-left: 1.5rem;
  }

  .page-about .timeline__node {
    left: -1.5rem;
  }
}

/* ---------- 平板与桌面 ---------- */

@media (min-width: 720px) {
  .page-about .partner-list {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 1.75rem;
  }

  .page-about .scale-list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 1.5rem 2.5rem;
  }
}

@media (min-width: 900px) {
  .page-about .team-list {
    grid-template-columns: repeat(12, minmax(0, 1fr));
    gap: 1.75rem 1.5rem;
  }

  .page-about .team-item:nth-child(1) {
    grid-column: 1 / span 5;
  }

  .page-about .team-item:nth-child(2) {
    grid-column: 7 / span 6;
  }

  .page-about .team-item:nth-child(3) {
    grid-column: 3 / span 6;
  }
}

@media (min-width: 1000px) {
  .page-about .about-shell {
    grid-template-columns: minmax(0, 32%) minmax(0, 1fr);
    gap: clamp(3rem, 6vw, 6rem);
  }

  .page-about .about-rail {
    position: sticky;
    top: calc(var(--header-h) + 2.25rem);
    align-self: start;
    padding-bottom: 0;
    border-bottom: 0;
  }

  .page-about .rail {
    display: block;
    overflow: visible;
    padding: .25rem 0 .25rem 1.5rem;
    background-image: linear-gradient(var(--ink-line-strong), var(--ink-line-strong));
    background-repeat: no-repeat;
    background-size: 1px calc(100% - 1.75rem);
    background-position: 4px .875rem;
  }

  .page-about .rail__item {
    display: block;
  }

  .page-about .rail__link {
    display: flex;
    align-items: baseline;
    gap: .6rem;
    position: relative;
    padding: .5rem 0;
    white-space: normal;
  }

  .page-about .rail__node {
    position: absolute;
    left: -1.5rem;
    top: .95rem;
    width: 9px;
    height: 9px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-figure img,
  .page-about .timeline__node,
  .page-about .rail__node,
  .page-about .team-item,
  .page-about .gate__summary,
  .page-about .sec a {
    transition: none;
  }

  .page-about .team-item:hover {
    transform: none;
  }
}
<<<END>>>