.page-about {
  --about-rail: 78px;
  --about-gap: clamp(20px, 3.6vw, 52px);
  --about-ink-rule: rgba(232, 180, 92, .26);
  background: var(--sand);
  color: var(--text);
  overflow-x: clip;
}

.page-about img {
  max-width: 100%;
  height: auto;
}

/* ============ 首屏 ============ */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding: clamp(24px, 4vw, 44px) 0 clamp(46px, 6vw, 84px);
  background:
    radial-gradient(130% 100% at 88% -18%, rgba(201, 138, 46, .34), transparent 58%),
    linear-gradient(178deg, var(--ink) 4%, var(--ink-2) 100%);
  color: var(--sand);
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  right: -6%;
  bottom: -1px;
  width: min(620px, 64%);
  height: 58%;
  background: linear-gradient(150deg, rgba(232, 180, 92, .18), rgba(232, 180, 92, 0) 72%);
  clip-path: polygon(24% 0, 100% 18%, 100% 100%, 0 100%);
  pointer-events: none;
}

.page-about .about-hero-inner {
  position: relative;
  z-index: 1;
  display: grid;
  gap: clamp(14px, 2vw, 22px);
}

.page-about .about-hero .breadcrumb,
.page-about .about-hero .breadcrumb-list,
.page-about .about-hero .breadcrumb-list a,
.page-about .about-hero .breadcrumb-list li {
  color: rgba(242, 228, 201, .66);
  font-family: var(--font-narrow);
  font-size: 12px;
  letter-spacing: .1em;
}

.page-about .about-hero .breadcrumb-list a {
  text-decoration: none;
  border-bottom: 1px solid rgba(232, 180, 92, .42);
  transition: color var(--t), border-color var(--t);
}

.page-about .about-hero .breadcrumb-list a:hover {
  color: var(--amber-hi);
  border-bottom-color: var(--amber-hi);
}

.page-about .about-hero-eyebrow {
  margin: 0;
  color: var(--amber-hi);
}

.page-about .about-hero h1 {
  margin: 0;
  max-width: 15em;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(36px, 6.2vw, 82px);
  line-height: 1.08;
  letter-spacing: -.02em;
  color: var(--glass);
}

.page-about .about-hero .lede {
  margin: 0;
  max-width: 34em;
  font-size: clamp(15px, 1.6vw, 17px);
  line-height: 1.95;
  color: rgba(242, 228, 201, .86);
}

.page-about .hero-facts {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 30px;
  margin: 6px 0 0;
  padding: 18px 0 0;
  list-style: none;
  border-top: 1px solid rgba(232, 180, 92, .28);
}

.page-about .hero-facts li {
  display: flex;
  align-items: baseline;
  gap: 7px;
  font-size: 12.5px;
  letter-spacing: .05em;
  color: rgba(242, 228, 201, .78);
}

.page-about .hero-facts b {
  font-family: var(--font-narrow);
  font-size: 21px;
  font-weight: 600;
  letter-spacing: .02em;
  color: var(--amber-hi);
}

/* ============ 开篇意象图 ============ */
.page-about .about-band {
  background: var(--sand);
  padding: clamp(20px, 3vw, 34px) 0 clamp(6px, 1.4vw, 14px);
}

.page-about .about-frame--wide {
  aspect-ratio: 16 / 6;
}

.page-about .about-band .figure-caption {
  margin-top: 12px;
  padding-top: 10px;
  border-top: 1px solid rgba(14, 36, 56, .12);
  font-size: 12px;
  letter-spacing: .04em;
  color: var(--muted);
}

/* ============ 运河走廊 ============ */
.page-about .about-corridor {
  display: grid;
  grid-template-columns: var(--about-rail) minmax(0, 1fr);
  gap: var(--about-gap);
  align-items: start;
  padding-top: clamp(28px, 5vw, 62px);
  padding-bottom: clamp(38px, 6vw, 78px);
}

.page-about .about-rail {
  position: sticky;
  top: 96px;
  z-index: 2;
}

.page-about .about-rail-list {
  display: flex;
  flex-direction: column;
  gap: 4px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-rail-list a {
  display: flex;
  flex-direction: column;
  gap: 5px;
  padding: 10px 8px;
  border-left: 2px solid rgba(14, 36, 56, .14);
  color: var(--muted);
  text-decoration: none;
  transition: color var(--t), border-color var(--t), background-color var(--t);
}

.page-about .about-rail-list a:hover,
.page-about .about-rail-list a:focus-visible {
  border-left-color: var(--amber);
  background: rgba(251, 246, 236, .8);
  color: var(--ink);
  outline: none;
}

.page-about .about-rail-list a:focus-visible {
  box-shadow: 0 0 0 2px var(--amber);
}

.page-about .about-rail-num {
  font-family: var(--font-narrow);
  font-size: 11px;
  letter-spacing: .16em;
  color: var(--amber);
}

.page-about .about-rail-label {
  font-family: var(--font-narrow);
  font-size: 11px;
  line-height: 1.5;
  letter-spacing: .08em;
  color: inherit;
}

/* ============ 章节通用 ============ */
.page-about .about-chapter {
  scroll-margin-top: 104px;
  margin-bottom: clamp(42px, 6vw, 82px);
}

.page-about .about-chapter:last-of-type {
  margin-bottom: 0;
}

.page-about .about-chapter-head {
  margin-bottom: clamp(20px, 3vw, 32px);
}

.page-about .about-chapter .eyebrow {
  margin: 0 0 10px;
  color: var(--coral);
}

.page-about .about-chapter h2 {
  margin: 0 0 14px;
  max-width: 20em;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(25px, 3.4vw, 40px);
  line-height: 1.24;
  letter-spacing: -.015em;
  color: var(--ink);
}

.page-about .about-chapter-lede {
  margin: 0;
  max-width: 34em;
  font-size: 16px;
  line-height: 1.9;
  color: var(--muted);
}

.page-about .about-chapter--ink {
  padding: clamp(22px, 3.4vw, 44px);
  border: 1px solid var(--about-ink-rule);
  border-radius: 2px 26px 2px 26px;
  background: linear-gradient(160deg, var(--ink) 0%, var(--ink-2) 74%, var(--ink-3) 100%);
  color: rgba(242, 228, 201, .84);
}

.page-about .about-chapter--ink h2 {
  color: var(--glass);
}

.page-about .about-chapter--ink .eyebrow {
  color: var(--amber-hi);
}

.page-about .about-chapter--ink .about-chapter-lede,
.page-about .about-chapter--ink p {
  color: rgba(242, 228, 201, .82);
}

.page-about .about-chapter--ink .btn--outline {
  border-color: rgba(232, 180, 92, .6);
  color: var(--amber-hi);
}

/* ============ 时间线 ============ */
.page-about .about-line {
  display: flex;
  flex-direction: column;
  gap: clamp(14px, 2vw, 22px);
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-node {
  display: grid;
  grid-template-columns: minmax(0, 132px) minmax(0, 1fr);
  gap: clamp(10px, 1.8vw, 22px);
  align-items: start;
}

.page-about .about-node-year {
  margin: 2px 0 0;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(20px, 2.2vw, 27px);
  line-height: 1.16;
  letter-spacing: -.03em;
  color: rgba(14, 36, 56, .24);
  text-shadow: 0 1px 0 rgba(251, 246, 236, .95);
  font-variant-numeric: tabular-nums;
  overflow-wrap: anywhere;
}

.page-about .about-sheet {
  border: 1px solid rgba(14, 36, 56, .12);
  border-left: 3px solid var(--amber);
  border-radius: 0 3px 3px 0;
  background: var(--glass);
  box-shadow: 0 16px 28px -26px rgba(14, 36, 56, .75);
  transition: border-color var(--t), transform var(--t), box-shadow var(--t);
}

.page-about .about-sheet:hover {
  border-left-color: var(--amber-hi);
  transform: translateY(-2px);
  box-shadow: 0 20px 30px -24px rgba(14, 36, 56, .7);
}

.page-about .about-sheet summary {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px 12px;
  padding: 14px 18px;
  list-style: none;
  cursor: pointer;
}

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

.page-about .about-sheet summary:focus-visible {
  outline: 2px solid var(--amber);
  outline-offset: 2px;
}

.page-about .about-sheet-title {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(16px, 1.9vw, 20px);
  line-height: 1.5;
  letter-spacing: -.01em;
  color: var(--ink);
}

.page-about .about-sheet summary::after {
  content: "展开";
  margin-left: auto;
  font-family: var(--font-narrow);
  font-size: 11px;
  letter-spacing: .14em;
  color: var(--muted);
}

.page-about .about-sheet[open] summary::after {
  content: "收起";
  color: var(--green);
}

.page-about .about-sheet-body {
  margin-top: 2px;
  padding: 0 18px 16px;
  border-top: 1px solid rgba(14, 36, 56, .08);
}

.page-about .about-sheet-body p {
  margin: 12px 0 0;
  max-width: 36em;
  font-size: 15px;
  line-height: 1.95;
  color: var(--text);
}

/* ============ 拱桥分隔 ============ */
.page-about .about-bridge {
  margin: clamp(6px, 1.4vw, 14px) 0 clamp(32px, 5vw, 62px);
  color: rgba(201, 138, 46, .5);
}

.page-about .about-bridge svg {
  display: block;
  width: 100%;
  height: clamp(24px, 4vw, 44px);
}

/* ============ 首屏改版 ============ */
.page-about .revamp-grid {
  display: grid;
  gap: clamp(20px, 3vw, 36px);
  align-items: center;
}

.page-about .revamp-copy p {
  margin: 0 0 14px;
  max-width: 34em;
  font-size: 15.5px;
  line-height: 1.95;
}

.page-about .revamp-copy p:last-of-type {
  margin-bottom: 0;
}

.page-about .about-ratio {
  display: flex;
  flex-direction: column;
  gap: 8px;
  max-width: 420px;
  margin-top: clamp(18px, 2.6vw, 26px);
}

.page-about .about-ratio-bar {
  display: flex;
  align-items: center;
  height: 34px;
  padding: 0 12px;
  border: 1px solid var(--about-ink-rule);
  border-radius: 1px 12px 1px 12px;
  background: rgba(232, 180, 92, .1);
  font-family: var(--font-narrow);
  font-size: 11px;
  letter-spacing: .12em;
  color: rgba(242, 228, 201, .9);
  white-space: nowrap;
  overflow: hidden;
}

.page-about .about-ratio-bar--main {
  width: 100%;
  border-color: rgba(232, 180, 92, .6);
  background: rgba(201, 138, 46, .32);
  color: var(--glass);
}

.page-about .about-ratio-bar--sub {
  width: 62.5%;
}

.page-about .revamp-figure .figure-caption,
.page-about .collab-figure .figure-caption {
  margin-top: 10px;
  font-size: 12px;
  letter-spacing: .04em;
  color: rgba(242, 228, 201, .62);
}

.page-about .collab-figure .figure-caption {
  color: var(--muted);
}

/* ============ 更新链条 ============ */
.page-about .rhythm-steps {
  display: grid;
  gap: clamp(12px, 1.8vw, 18px);
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .rhythm-step {
  padding: 18px 18px 20px;
  border: 1px solid rgba(14, 36, 56, .12);
  border-top: 3px solid var(--amber);
  border-radius: 0 0 3px 3px;
  background: var(--glass);
  transition: transform var(--t), border-color var(--t);
}

.page-about .rhythm-step:hover {
  transform: translateY(-2px);
  border-top-color: var(--coral);
}

.page-about .rhythm-num {
  display: block;
  margin-bottom: 8px;
  font-family: var(--font-narrow);
  font-size: 11px;
  letter-spacing: .2em;
  color: var(--amber);
}

.page-about .rhythm-step h3 {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-size: 18px;
  letter-spacing: -.01em;
  color: var(--ink);
}

.page-about .rhythm-step p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.9;
  color: var(--text);
}

.page-about .rhythm-foot {
  margin: clamp(18px, 2.6vw, 26px) 0 0;
  max-width: 36em;
  padding-left: 14px;
  border-left: 2px solid var(--coral);
  font-size: 14.5px;
  line-height: 1.9;
  color: var(--muted);
}

/* ============ 编排协作 ============ */
.page-about .collab-grid {
  display: grid;
  gap: clamp(20px, 3vw, 36px);
  align-items: center;
}

.page-about .collab-list {
  display: flex;
  flex-direction: column;
  gap: 14px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .collab-list li {
  padding-left: 14px;
  border-left: 2px solid rgba(201, 138, 46, .45);
}

.page-about .collab-list h3 {
  margin: 0 0 4px;
  font-family: var(--font-display);
  font-size: 17px;
  color: var(--ink);
}

.page-about .collab-list p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.9;
  color: var(--text);
}

.page-about .collab-note {
  margin: clamp(16px, 2.4vw, 22px) 0 0;
  padding: 14px 16px;
  border: 1px dashed rgba(201, 138, 46, .42);
  border-radius: 2px;
  background: rgba(251, 246, 236, .75);
  font-size: 14.5px;
  line-height: 1.9;
  color: var(--muted);
}

/* ============ 属地服务 ============ */
.page-about .local-grid {
  display: grid;
  gap: clamp(20px, 3vw, 34px);
  align-items: start;
}

.page-about .local-copy p {
  margin: 0 0 14px;
  max-width: 34em;
  font-size: 15.5px;
  line-height: 1.95;
}

.page-about .local-links {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: clamp(16px, 2.4vw, 24px);
}

.page-about .local-card {
  padding: clamp(16px, 2.4vw, 24px);
  border: 1px solid rgba(232, 180, 92, .34);
  border-radius: 2px 18px 2px 18px;
  background: rgba(251, 246, 236, .07);
}

.page-about .local-card-title {
  margin: 0 0 14px;
  font-family: var(--font-narrow);
  font-size: 11px;
  letter-spacing: .2em;
  color: var(--amber-hi);
}

.page-about .local-list {
  margin: 0;
  padding: 0;
}

.page-about .local-list > div {
  padding: 12px 0;
  border-top: 1px solid rgba(232, 180, 92, .16);
}

.page-about .local-list > div:first-child {
  padding-top: 0;
  border-top: 0;
}

.page-about .local-list dt {
  margin-bottom: 5px;
  font-family: var(--font-narrow);
  font-size: 11px;
  letter-spacing: .14em;
  color: rgba(242, 228, 201, .58);
}

.page-about .local-list dd {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.7;
  color: var(--glass);
  overflow-wrap: anywhere;
}

/* ============ 延伸入口 ============ */
.page-about .about-next {
  padding: clamp(36px, 5vw, 70px) 0 clamp(40px, 6vw, 80px);
  background: linear-gradient(168deg, var(--ink) 0%, var(--ink-2) 100%);
}

.page-about .about-next-title {
  margin: 0 0 clamp(18px, 2.6vw, 28px);
  font-family: var(--font-display);
  font-size: clamp(22px, 3vw, 32px);
  letter-spacing: -.01em;
  color: var(--glass);
}

.page-about .about-next-grid {
  display: grid;
  gap: 12px;
}

.page-about .about-next-card {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 20px 18px;
  border: 1px solid rgba(232, 180, 92, .24);
  border-radius: 1px 14px 1px 14px;
  background: rgba(251, 246, 236, .04);
  text-decoration: none;
  color: rgba(242, 228, 201, .8);
  transition: border-color var(--t), background-color var(--t), transform var(--t);
}

.page-about .about-next-card:hover,
.page-about .about-next-card:focus-visible {
  border-color: var(--amber-hi);
  background: rgba(232, 180, 92, .1);
  transform: translateY(-2px);
  outline: none;
}

.page-about .about-next-card:focus-visible {
  box-shadow: 0 0 0 2px var(--amber);
}

.page-about .about-next-num {
  font-family: var(--font-narrow);
  font-size: 11px;
  letter-spacing: .2em;
  color: var(--amber);
}

.page-about .about-next-card h3 {
  margin: 0;
  font-family: var(--font-display);
  font-size: 18px;
  color: var(--glass);
}

.page-about .about-next-card p {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
}

.page-about .about-next-go {
  margin-top: auto;
  padding-top: 10px;
  font-family: var(--font-narrow);
  font-size: 11px;
  letter-spacing: .16em;
  color: var(--amber-hi);
}

/* ============ 响应式 ============ */
@media (min-width: 880px) {
  .page-about .revamp-grid {
    grid-template-columns: minmax(0, 1.06fr) minmax(0, .86fr);
  }

  .page-about .collab-grid {
    grid-template-columns: minmax(0, .9fr) minmax(0, 1.1fr);
  }

  .page-about .local-grid {
    grid-template-columns: minmax(0, 1.1fr) minmax(0, .9fr);
  }
}

@media (min-width: 760px) {
  .page-about .about-next-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

@media (min-width: 900px) {
  .page-about .rhythm-steps {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 900px) {
  .page-about .about-corridor {
    grid-template-columns: minmax(0, 1fr);
    gap: 22px;
  }

  .page-about .about-rail {
    position: static;
    top: auto;
  }

  .page-about .about-rail-list {
    flex-direction: row;
    gap: 8px;
    overflow-x: auto;
    padding-bottom: 8px;
    scrollbar-width: thin;
  }

  .page-about .about-rail-list li {
    flex: 0 0 auto;
  }

  .page-about .about-rail-list a {
    flex-direction: row;
    align-items: center;
    gap: 6px;
    padding: 8px 12px;
    border-left: 0;
    border-bottom: 2px solid rgba(14, 36, 56, .14);
    background: rgba(251, 246, 236, .7);
    white-space: nowrap;
  }

  .page-about .about-rail-list a:hover,
  .page-about .about-rail-list a:focus-visible {
    border-left: 0;
    border-bottom-color: var(--amber);
  }
}

@media (max-width: 720px) {
  .page-about .about-frame--wide {
    aspect-ratio: 4 / 3;
  }

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

  .page-about .about-node-year {
    margin-top: 0;
    font-size: 26px;
    color: rgba(14, 36, 56, .32);
  }

  .page-about .about-sheet summary {
    padding: 13px 14px;
  }

  .page-about .about-sheet-body {
    padding: 0 14px 14px;
  }

  .page-about .about-sheet summary::after {
    letter-spacing: .1em;
  }

  .page-about .about-ratio-bar {
    font-size: 10px;
    letter-spacing: .06em;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-sheet,
  .page-about .rhythm-step,
  .page-about .about-next-card,
  .page-about .about-rail-list a,
  .page-about .about-hero .breadcrumb-list a {
    transition: none;
  }

  .page-about .about-sheet:hover,
  .page-about .rhythm-step:hover,
  .page-about .about-next-card:hover {
    transform: none;
  }
}
<<<END>>>