.page-about {
  --about-pad: clamp(40px, 7vw, 88px);
  --about-narrow: 62ch;
  overflow-x: hidden;
}

.page-about .about-head {
  padding-top: clamp(24px, 5vw, 56px);
  padding-bottom: clamp(28px, 5vw, 52px);
}

.page-about .crumbs {
  margin-bottom: clamp(20px, 4vw, 36px);
}

/* 首屏封面 */
.page-about .about-cover {
  display: grid;
  gap: 28px;
  align-items: end;
}

.page-about .about-cover__main h1 {
  margin: 14px 0 0;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(30px, 7.4vw, 62px);
  line-height: 1.08;
  letter-spacing: -0.02em;
  color: var(--ink-teal);
  text-wrap: balance;
}

.page-about .about-cover__lede {
  margin: 20px 0 0;
  max-width: 40em;
  font-family: var(--font-body);
  font-size: clamp(15px, 2.6vw, 18px);
  line-height: 1.9;
  color: var(--ink-teal);
}

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

.page-about .about-aside__head {
  margin: 0 0 12px;
  color: var(--jiang);
}

.page-about .fact-list {
  list-style: none;
  margin: 0;
  padding: 18px 20px;
  display: grid;
  gap: 14px;
  border: var(--line-bold) solid var(--ink-teal);
  border-radius: var(--radius-card);
  background: var(--paper-white);
  box-shadow: var(--shadow-hard);
}

.page-about .fact-list__item {
  display: grid;
  gap: 2px;
  padding-bottom: 12px;
  border-bottom: 1px dashed var(--stand);
}

.page-about .fact-list__item:last-child {
  padding-bottom: 0;
  border-bottom: 0;
}

.page-about .fact-list__num {
  font-family: var(--font-mono);
  font-size: 26px;
  font-weight: 700;
  line-height: 1.1;
  color: var(--jiang);
}

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

/* 章节目录 */
.page-about .about-toc {
  margin-top: clamp(28px, 5vw, 44px);
  border-top: var(--line) solid var(--ink-teal);
  border-bottom: var(--line) dashed var(--stand);
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

.page-about .about-toc__list {
  list-style: none;
  display: flex;
  gap: 8px;
  margin: 0;
  padding: 12px 0;
  min-width: max-content;
}

.page-about .about-toc__link {
  display: inline-block;
  padding: 8px 14px;
  border: var(--line) solid transparent;
  border-radius: var(--radius-pill);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  text-decoration: none;
  color: var(--ink-teal);
  white-space: nowrap;
  transition: background-color 0.2s var(--ease), color 0.2s var(--ease), border-color 0.2s var(--ease);
}

.page-about .about-toc__link:hover,
.page-about .about-toc__link:focus-visible {
  border-color: var(--jiang);
  background: var(--rain);
}

.page-about .about-toc__link[aria-current="true"] {
  background: var(--signal);
  border-color: var(--signal);
  color: var(--night);
  font-weight: 700;
}

/* 章节骨架 */
.page-about .about-chapter {
  padding-block: var(--about-pad);
  border-top: var(--line) dashed var(--stand);
}

.page-about .about-chapter__head {
  display: grid;
  gap: 12px;
  margin-bottom: clamp(24px, 4vw, 40px);
  max-width: 46em;
}

.page-about .about-chapter__head h2 {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(24px, 5vw, 40px);
  line-height: 1.16;
  letter-spacing: -0.015em;
  color: var(--ink-teal);
}

.page-about .about-chapter__lede {
  margin: 0;
  font-family: var(--font-ui);
  font-size: 15px;
  line-height: 1.8;
  color: var(--jiang);
}

.page-about .about-chapter--inset .about-chapter__head {
  max-width: 36em;
}

.page-about .about-inline-link {
  color: var(--ember);
  text-decoration: underline;
  text-underline-offset: 3px;
}

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

/* 第一章 */
.page-about .about-lead {
  display: grid;
  gap: 26px;
}

.page-about .about-lead__text {
  max-width: var(--about-narrow);
}

.page-about .about-lead__text p {
  margin: 0 0 18px;
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.9;
  color: var(--ink-teal);
}

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

.page-about .about-note {
  align-self: start;
  padding: 18px 20px;
  border: var(--line-bold) solid var(--jiang);
  border-left-width: 8px;
  border-radius: 4px;
  background: var(--rain);
}

.page-about .about-note .label-mono {
  margin: 0 0 8px;
  color: var(--jiang);
}

.page-about .about-note__title {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 20px;
  color: var(--ink-teal);
}

.page-about .about-note__body {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--ink-teal);
}

.page-about .about-banner {
  margin-top: clamp(28px, 5vw, 44px);
}

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

/* 第二章 城市网络 */
.page-about .about-band--rain {
  background: var(--rain);
}

.page-about .about-city {
  display: grid;
  gap: 28px;
}

.page-about .city-map {
  display: block;
  width: 100%;
  max-width: 620px;
  height: auto;
  margin-inline: auto;
}

.page-about .city-map__grid path {
  fill: none;
  stroke: rgba(29, 78, 86, 0.14);
  stroke-width: 1;
}

.page-about .city-map__outline {
  fill: var(--paper-white);
  stroke: var(--jiang);
  stroke-width: 2.5;
}

.page-about .city-map__links path {
  fill: none;
  stroke: var(--jiang);
  stroke-width: 1.4;
  stroke-dasharray: 4 7;
  opacity: 0.55;
}

.page-about .city-node circle {
  fill: var(--jiang);
  transition: fill 0.2s var(--ease);
}

.page-about .city-node text {
  font-family: var(--font-mono);
  font-size: 17px;
  fill: var(--ink-teal);
  pointer-events: none;
}

.page-about .city-node:hover circle,
.page-about .city-node:focus-within circle {
  fill: var(--signal);
}

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

.page-about .city-list__item {
  display: grid;
  gap: 2px;
  padding: 11px 0;
  border-bottom: 1px solid rgba(29, 78, 86, 0.25);
}

.page-about .city-list__name {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 16px;
  color: var(--ink-teal);
}

.page-about .city-list__desc {
  font-size: 13px;
  line-height: 1.7;
  color: var(--jiang);
}

/* 第三章 岗位 */
.page-about .about-team {
  display: grid;
  gap: 28px;
}

.page-about .role-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 16px;
}

.page-about .role-card {
  padding: 18px 20px 20px;
  border: var(--line-bold) solid var(--ink-teal);
  border-radius: 4px;
  background: var(--paper-white);
  box-shadow: var(--shadow-hard);
}

.page-about .role-card__tag {
  display: inline-block;
  margin: 0 0 10px;
  padding: 3px 9px;
  border-radius: 3px;
  background: var(--jiang);
  color: var(--paper-white);
  font-size: 11px;
  letter-spacing: 0.1em;
}

.page-about .role-card__title {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 20px;
  color: var(--ink-teal);
}

.page-about .role-card__body {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--ink-teal);
}

.page-about .about-team__figure {
  align-self: start;
}

/* 第四章 流程 */
.page-about .gate-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 20px;
}

.page-about .gate {
  padding: 4px 0 4px 18px;
  border-left: 5px solid var(--signal);
}

.page-about .gate__num {
  margin: 0 0 6px;
  color: var(--ember);
}

.page-about .gate__title {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 19px;
  color: var(--ink-teal);
}

.page-about .gate__body {
  margin: 0;
  font-size: 14px;
  line-height: 1.85;
  color: var(--ink-teal);
}

.page-about .about-timing {
  margin-top: clamp(26px, 4vw, 40px);
  padding: 20px 22px;
  border: var(--line) solid var(--jiang);
  border-radius: 4px;
  background: var(--paper-white);
  box-shadow: var(--shadow-soft);
}

.page-about .about-timing__main {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(17px, 3.6vw, 22px);
  color: var(--ink-teal);
}

.page-about .about-timing__main strong,
.page-about .about-timing__sub strong {
  font-family: var(--font-mono);
  color: var(--signal);
}

.page-about .about-timing__sub {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--jiang);
}

/* 第五章 时间线 */
.page-about .about-band--night {
  background: var(--night);
  border-top-color: var(--night);
}

.page-about .about-band--night .about-chapter__head h2 {
  color: var(--paper);
}

.page-about .about-band--night .about-chapter__lede {
  color: var(--rain);
}

.page-about .about-band--night .chapter-tag {
  background: var(--signal);
  color: var(--night);
}

.page-about .timeline {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .timeline__item {
  display: grid;
  grid-template-columns: 68px minmax(0, 1fr);
  gap: 14px;
  padding: 20px 0;
  border-top: 1px solid rgba(216, 230, 227, 0.28);
}

.page-about .timeline__item:first-child {
  border-top: 2px solid var(--rain);
}

.page-about .timeline__year {
  font-family: var(--font-mono);
  font-size: 19px;
  font-weight: 700;
  color: var(--signal);
  letter-spacing: 0.02em;
}

.page-about .timeline__item--version .timeline__year {
  color: var(--rain);
  font-size: 15px;
  padding-top: 3px;
}

.page-about .timeline__title {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 18px;
  line-height: 1.4;
  color: var(--paper);
}

.page-about .timeline__body p {
  margin: 0;
  max-width: 56ch;
  font-family: var(--font-body);
  font-size: 14px;
  line-height: 1.85;
  color: var(--rain);
}

/* 第六章 合作生态 */
.page-about .partner-grid {
  display: grid;
  gap: 18px;
}

.page-about .partner-block {
  padding: 20px 22px;
  border-top: var(--line-bold) solid var(--jiang);
  background: var(--paper-white);
}

.page-about .partner-block__title {
  margin: 0 0 10px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 18px;
  color: var(--ink-teal);
}

.page-about .partner-block p {
  margin: 0;
  font-family: var(--font-body);
  font-size: 14px;
  line-height: 1.85;
  color: var(--ink-teal);
}

/* 第七章 合作方式 */
.page-about .about-band--coop {
  background: var(--paper-white);
}

.page-about .coop-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 16px;
}

.page-about .coop-card {
  position: relative;
  padding: 20px 20px 22px;
  border: var(--line) solid var(--ink-teal);
  border-radius: 4px;
  background: var(--paper);
  box-shadow: var(--shadow-soft);
  transition: transform 0.2s var(--ease), box-shadow 0.2s var(--ease);
}

.page-about .coop-card:hover {
  transform: translate(-3px, -3px);
  box-shadow: var(--shadow-hard);
}

.page-about .coop-card__index {
  display: inline-block;
  margin: 0 0 10px;
  padding: 2px 8px;
  border: 2px solid var(--signal);
  border-radius: 3px;
  color: var(--ember);
  font-size: 12px;
}

.page-about .coop-card__title {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 19px;
  color: var(--ink-teal);
}

.page-about .coop-card__body {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--ink-teal);
}

.page-about .coop-start {
  margin-top: clamp(26px, 4vw, 40px);
  display: grid;
  gap: 24px;
  padding: 24px 22px;
  border: var(--line-bold) solid var(--ink-teal);
  border-radius: 4px;
  background: var(--rain);
  box-shadow: var(--shadow-hard);
}

.page-about .coop-start__title {
  margin: 0 0 10px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(20px, 4.4vw, 26px);
  color: var(--ink-teal);
}

.page-about .coop-start__text p {
  margin: 0;
  max-width: 44em;
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.85;
  color: var(--ink-teal);
}

.page-about .coop-start__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 18px;
}

.page-about .coop-start__contact {
  padding-top: 20px;
  border-top: 2px dashed var(--jiang);
}

.page-about .coop-start__contact .label-mono {
  margin: 0 0 10px;
  color: var(--jiang);
}

.page-about .coop-start__line {
  margin: 10px 0 2px;
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--jiang);
}

.page-about .coop-start__value {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 15px;
  word-break: break-all;
  color: var(--ink-teal);
}

.page-about .coop-start__hours {
  margin: 12px 0 0;
  font-size: 13px;
  color: var(--jiang);
}

.page-about .coop-start__contact .btn {
  margin-top: 12px;
}

/* 平板与桌面 */
@media (min-width: 700px) {
  .page-about .city-list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    column-gap: 28px;
  }

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

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

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

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

@media (min-width: 900px) {
  .page-about .about-cover {
    grid-template-columns: minmax(0, 1.4fr) minmax(280px, 0.6fr);
    gap: 48px;
  }

  .page-about .about-lead {
    grid-template-columns: minmax(0, 1.5fr) minmax(260px, 0.5fr);
    gap: 48px;
    align-items: start;
  }

  .page-about .about-city {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    gap: 44px;
    align-items: start;
  }

  .page-about .about-team {
    grid-template-columns: minmax(0, 1.35fr) minmax(0, 0.65fr);
    gap: 44px;
    align-items: start;
  }

  .page-about .timeline__item {
    grid-template-columns: 140px minmax(0, 1fr);
    gap: 28px;
    padding: 24px 0;
  }

  .page-about .timeline__year {
    font-size: 24px;
  }

  .page-about .coop-start {
    grid-template-columns: minmax(0, 1.4fr) minmax(260px, 0.6fr);
    gap: 40px;
    padding: 32px 30px;
  }

  .page-about .coop-start__contact {
    padding-top: 0;
    padding-left: 28px;
    border-top: 0;
    border-left: 2px dashed var(--jiang);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .coop-card,
  .page-about .city-node circle,
  .page-about .about-toc__link {
    transition: none;
  }

  .page-about .coop-card:hover {
    transform: none;
  }
}
<<<END>>>