.page-about {
  --about-card: rgba(35, 48, 90, .55);
  --about-soft: rgba(245, 239, 227, .05);
  background: var(--ink);
  color: var(--paper);
  padding-bottom: clamp(56px, 9vw, 110px);
  overflow-x: clip;
}

/* 面包屑 */
.page-about .breadcrumbs {
  padding-top: clamp(16px, 3vw, 28px);
}
.page-about .breadcrumbs__list {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin: 0;
  padding: 0;
  list-style: none;
  font-family: var(--font-mono);
  font-size: var(--step-1);
  letter-spacing: .04em;
}
.page-about .breadcrumbs__item + .breadcrumbs__item::before {
  content: "/";
  margin-right: 6px;
  color: var(--text-dim);
}
.page-about .breadcrumbs__link {
  color: var(--text-dim);
  text-decoration: none;
}
.page-about .breadcrumbs__link:hover,
.page-about .breadcrumbs__link:focus-visible {
  color: var(--gold);
}
.page-about .breadcrumbs__current {
  color: var(--gold);
}

/* 首屏 */
.about-hero {
  position: relative;
  padding-block: clamp(22px, 4vw, 44px) clamp(38px, 7vw, 76px);
}
.about-hero::before {
  content: "";
  position: absolute;
  top: -18%;
  right: -14%;
  width: min(660px, 92vw);
  height: min(660px, 92vw);
  background: radial-gradient(circle at 58% 42%, rgba(224, 138, 46, .20), rgba(62, 142, 138, .12) 46%, transparent 72%);
  pointer-events: none;
}
.about-hero__inner {
  position: relative;
  display: grid;
  gap: clamp(26px, 5vw, 48px);
  align-items: center;
}
.about-hero__copy {
  min-width: 0;
}
.about-hero__title {
  margin: 12px 0 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(2.15rem, 8.4vw, 4.4rem);
  line-height: 1.1;
  letter-spacing: -.02em;
}
.about-hero__title em {
  display: inline-block;
  font-style: normal;
  color: var(--gold);
  transform: rotate(-1.5deg);
  padding-bottom: .06em;
  border-bottom: 6px solid rgba(224, 138, 46, .55);
}
.about-hero__lead {
  margin: 20px 0 0;
  max-width: 34em;
  font-size: clamp(1rem, 2.6vw, 1.15rem);
  line-height: 1.8;
  color: var(--text-soft);
}
.about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 26px;
}
.about-hero__meta {
  display: grid;
  gap: 10px;
  margin: 30px 0 0;
  padding: 0;
  list-style: none;
  font-size: var(--step0);
  color: var(--text-soft);
}
.about-hero__meta li {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--line-soft);
}
.about-hero__num {
  font-family: var(--font-mono);
  font-size: var(--step3);
  line-height: 1;
  color: var(--amber);
  letter-spacing: .02em;
}
.about-hero__figure {
  position: relative;
  margin: 0;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: var(--ink-2);
}
.about-hero__figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  aspect-ratio: 16 / 10;
  object-fit: cover;
}
.about-hero__figure figcaption {
  padding: 12px 16px;
  font-size: var(--step-1);
  line-height: 1.6;
  color: var(--text-soft);
  background: rgba(16, 23, 40, .55);
}

/* 主体：索引 + 章节 */
.about-body {
  display: grid;
  gap: clamp(22px, 4vw, 40px);
  align-items: start;
}
.about-sections {
  min-width: 0;
}
.about-rail {
  min-width: 0;
}
.about-rail__title {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: var(--step-1);
  letter-spacing: .12em;
  color: var(--text-dim);
}
.about-rail__list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0;
  padding: 0;
  list-style: none;
}
.about-rail__link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 14px;
  border: 1px solid var(--line);
  border-radius: 999px;
  color: var(--text-soft);
  font-size: var(--step0);
  text-decoration: none;
  transition: color .25s var(--ease), border-color .25s var(--ease), background-color .25s var(--ease);
}
.about-rail__link:hover,
.about-rail__link:focus-visible {
  color: var(--ink);
  background: var(--amber);
  border-color: var(--amber);
}
.about-rail__num {
  font-family: var(--font-mono);
  font-size: var(--step-1);
  color: var(--gold);
}
.about-rail__link:hover .about-rail__num,
.about-rail__link:focus-visible .about-rail__num {
  color: var(--ink);
}
.about-rail__note {
  margin: 14px 0 0;
  font-size: var(--step-1);
  line-height: 1.7;
  color: var(--text-dim);
  max-width: 22em;
}

/* 章节 */
.about-chapter {
  padding-block: clamp(30px, 5.5vw, 56px);
  border-top: 1px solid var(--line-soft);
}
.about-chapter:first-child {
  border-top: 0;
  padding-top: clamp(18px, 3vw, 30px);
}
.about-chapter__head {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  margin-bottom: 18px;
}
.about-chapter__num {
  flex: none;
  margin-top: .35em;
  padding: 3px 8px;
  border: 1px solid rgba(242, 193, 78, .45);
  border-radius: 8px;
  font-family: var(--font-mono);
  font-size: var(--step-1);
  letter-spacing: .06em;
  color: var(--gold);
}
.about-chapter__title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.5rem, 4.6vw, 2.4rem);
  line-height: 1.28;
  letter-spacing: -.01em;
}
.about-chapter__lead {
  margin: 0 0 16px;
  font-size: clamp(1rem, 2.5vw, 1.15rem);
  line-height: 1.85;
  color: var(--paper);
  max-width: 36em;
}
.about-chapter p {
  margin: 0 0 14px;
  max-width: 38em;
  font-size: var(--step1);
  line-height: 1.85;
  color: var(--text-soft);
}
.about-chapter p:last-child {
  margin-bottom: 0;
}

/* 三段式 */
.about-triad {
  display: grid;
  gap: 14px;
  margin: 22px 0;
}
.about-triad__item {
  padding: 20px 20px 18px;
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  background: var(--about-card);
}
.about-triad__title {
  margin: 12px 0 8px;
  font-family: var(--font-display);
  font-size: var(--step2);
  line-height: 1.35;
}
.about-triad__item p {
  margin: 0;
  font-size: var(--step0);
  line-height: 1.8;
  color: var(--text-soft);
}

/* 校对：图文 + 折叠 */
.about-proof {
  display: grid;
  gap: 22px;
  margin: 20px 0 8px;
  align-items: start;
}
.about-proof__figure {
  margin: 0;
  border-radius: var(--radius-md);
  overflow: hidden;
  border: 1px solid var(--line);
  background: var(--ink-2);
}
.about-proof__figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
}
.about-folds {
  margin-top: 22px;
}
.about-fold {
  margin-bottom: 10px;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  background: var(--about-soft);
}
.about-fold summary {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 14px 16px;
  cursor: pointer;
  list-style: none;
  font-size: var(--step1);
  font-weight: 600;
  color: var(--paper);
}
.about-fold summary::-webkit-details-marker {
  display: none;
}
.about-fold summary::after {
  content: "+";
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: var(--step2);
  line-height: 1;
  color: var(--amber);
}
.about-fold[open] summary::after {
  content: "–";
}
.about-fold summary:focus-visible {
  outline: 2px solid var(--gold);
  outline-offset: 2px;
}
.about-fold__code {
  flex: none;
  font-family: var(--font-mono);
  font-size: var(--step-1);
  color: var(--teal);
}
.about-fold__body {
  padding: 0 16px 16px;
  font-size: var(--step0);
  line-height: 1.85;
  color: var(--text-soft);
}

/* 时间线 */
.about-timeline {
  position: relative;
  margin: 24px 0 0;
  padding: 0 0 0 26px;
  list-style: none;
}
.about-timeline::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 8px;
  bottom: 12px;
  width: 2px;
  background: linear-gradient(180deg, var(--gold), rgba(242, 193, 78, .12));
}
.about-timeline__item {
  position: relative;
  padding-bottom: 26px;
}
.about-timeline__item:last-child {
  padding-bottom: 0;
}
.about-timeline__item::before {
  content: "";
  position: absolute;
  left: -26px;
  top: 8px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--gold);
  box-shadow: 0 0 0 4px rgba(242, 193, 78, .16);
}
.about-timeline__year {
  display: inline-block;
  margin-bottom: 8px;
  padding: 2px 10px;
  border-radius: 999px;
  background: rgba(242, 193, 78, .14);
  font-family: var(--font-mono);
  font-size: var(--step-1);
  letter-spacing: .06em;
  color: var(--gold);
}
.about-timeline__title {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-size: var(--step3);
  line-height: 1.35;
}
.about-timeline__item p {
  margin: 0;
  max-width: 36em;
  font-size: var(--step0);
  line-height: 1.85;
  color: var(--text-soft);
}

/* 团队 */
.about-team {
  display: grid;
  gap: 22px;
  margin: 20px 0 18px;
  align-items: start;
}
.about-roles {
  display: grid;
  gap: 10px;
}
.about-roles__item {
  display: flex;
  gap: 14px;
  padding: 16px 18px;
  border: 1px solid var(--line-soft);
  border-radius: var(--radius-sm);
  background: var(--about-soft);
}
.about-roles__code {
  flex: none;
  font-family: var(--font-mono);
  font-size: var(--step-1);
  letter-spacing: .06em;
  color: var(--teal);
  padding-top: 3px;
}
.about-roles__title {
  margin: 0 0 6px;
  font-family: var(--font-body);
  font-size: var(--step1);
  font-weight: 700;
  letter-spacing: .02em;
}
.about-roles__item p {
  margin: 0;
  font-size: var(--step0);
  line-height: 1.8;
  color: var(--text-soft);
}
.about-team__figure {
  margin: 0;
  border-radius: var(--radius-md);
  overflow: hidden;
  border: 1px solid var(--line);
  background: var(--ink-2);
}
.about-team__figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
}

/* 数据概览 */
.about-stats {
  display: grid;
  gap: 14px;
  margin: 22px 0 20px;
}
.about-stat {
  padding: 22px 20px;
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  background: linear-gradient(155deg, rgba(35, 48, 90, .9), rgba(20, 27, 51, .55));
  transition: transform .3s var(--ease), border-color .3s var(--ease);
}
.about-stat:hover,
.about-stat:focus-within {
  transform: translateY(-3px);
  border-color: rgba(242, 193, 78, .45);
}
.about-stat:focus-visible {
  outline: 2px solid var(--gold);
  outline-offset: 3px;
}
.about-stat__num {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(2rem, 7vw, 3.2rem);
  line-height: 1.05;
  color: var(--gold);
}
.about-stat__unit {
  margin-left: 4px;
  font-family: var(--font-body);
  font-size: var(--step2);
  font-weight: 600;
  color: var(--amber);
}
.about-stat__label {
  margin: 8px 0 10px;
  font-size: var(--step1);
  font-weight: 600;
  letter-spacing: .04em;
  color: var(--paper);
}
.about-stat__note {
  margin: 0;
  font-size: var(--step-1);
  line-height: 1.75;
  color: var(--text-dim);
}

/* 合作生态链接 */
.about-links {
  display: grid;
  gap: 10px;
  margin: 20px 0 0;
  padding: 0;
  list-style: none;
}
.about-links__item {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 16px 18px;
  border-left: 2px solid rgba(242, 193, 78, .5);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  background: var(--about-soft);
  text-decoration: none;
  transition: background-color .25s var(--ease), border-color .25s var(--ease);
}
.about-links__item:hover,
.about-links__item:focus-visible {
  background: rgba(224, 138, 46, .14);
  border-left-color: var(--amber);
}
.about-links__k {
  font-size: var(--step1);
  font-weight: 700;
  color: var(--paper);
}
.about-links__v {
  font-size: var(--step0);
  color: var(--text-dim);
}

/* 结语卡 */
.about-closing {
  padding-top: clamp(30px, 5vw, 52px);
}
.about-closing__card {
  padding: clamp(24px, 5vw, 44px);
  border-radius: var(--radius-lg);
  background: var(--paper);
  color: var(--ink);
}
.about-closing__line {
  margin: 0 0 14px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.5rem, 4.4vw, 2.3rem);
  line-height: 1.3;
  color: var(--ink);
}
.about-closing__text {
  margin: 0;
  max-width: 36em;
  font-size: var(--step1);
  line-height: 1.85;
  color: #3b4358;
}
.about-closing__actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 14px;
  margin-top: 24px;
}
.about-closing__link {
  display: inline-flex;
  align-items: center;
  padding: 10px 18px;
  border: 1px solid rgba(20, 27, 51, .35);
  border-radius: 999px;
  font-size: var(--step0);
  font-weight: 600;
  color: var(--ink);
  text-decoration: none;
  transition: background-color .25s var(--ease), border-color .25s var(--ease);
}
.about-closing__link:hover,
.about-closing__link:focus-visible {
  background: var(--mist);
  border-color: var(--ink);
}
.about-closing__contact {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  margin: 22px 0 0;
  padding-top: 18px;
  border-top: 1px solid rgba(20, 27, 51, .14);
  font-size: var(--step-1);
  color: #4a5165;
}
.about-closing__mail {
  font-family: var(--font-mono);
  font-size: var(--step-1);
  letter-spacing: .02em;
  color: var(--ink);
  word-break: break-all;
}

/* 平板 */
@media (min-width: 720px) {
  .about-hero__meta {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 16px;
  }
  .about-hero__meta li {
    flex-direction: column;
    gap: 6px;
    padding-bottom: 0;
    border-bottom: 0;
    border-left: 1px solid var(--line);
    padding-left: 14px;
  }
  .about-hero__figure figcaption {
    position: absolute;
    left: 16px;
    right: 16px;
    bottom: 16px;
    border-radius: var(--radius-sm);
    background: rgba(16, 23, 40, .74);
  }
  .about-triad {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    align-items: stretch;
  }
  .about-triad__item:nth-child(2) {
    margin-top: 16px;
  }
  .about-triad__item:nth-child(3) {
    margin-top: 32px;
  }
  .about-proof,
  .about-team {
    grid-template-columns: minmax(0, 1fr) minmax(0, .85fr);
    gap: 26px;
  }
  .about-stats {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .about-links {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
  .about-links__item {
    height: 100%;
  }
}

/* 桌面：分屏 + 粘性索引 + 错位仪表板 */
@media (min-width: 960px) {
  .about-hero__inner {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, .95fr);
    gap: clamp(40px, 5vw, 76px);
  }
  .about-hero__figure img {
    aspect-ratio: 4 / 3;
  }
  .about-proof,
  .about-team {
    grid-template-columns: minmax(0, 1.1fr) minmax(0, .9fr);
    gap: 32px;
  }
}

@media (min-width: 1020px) {
  .about-body {
    grid-template-columns: 190px minmax(0, 1fr);
    gap: clamp(40px, 5vw, 72px);
  }
  .about-rail {
    position: sticky;
    top: clamp(88px, 12vh, 116px);
    padding-left: 16px;
    border-left: 2px solid var(--line);
  }
  .about-rail__list {
    flex-direction: column;
    flex-wrap: nowrap;
    gap: 2px;
  }
  .about-rail__link {
    border: 0;
    border-radius: 10px;
    padding: 8px 10px;
    width: 100%;
  }
  .about-rail__link:hover,
  .about-rail__link:focus-visible {
    color: var(--ink);
  }
  .about-stats {
    grid-template-columns: repeat(6, minmax(0, 1fr));
    align-items: start;
  }
  .about-stat--a {
    grid-column: span 3;
  }
  .about-stat--b {
    grid-column: span 3;
    margin-top: 26px;
  }
  .about-stat--c {
    grid-column: span 2;
  }
  .about-stat--d {
    grid-column: span 4;
    margin-top: 18px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-stat,
  .page-about .about-rail__link,
  .page-about .about-links__item,
  .page-about .about-closing__link {
    transition: none;
  }
  .page-about .about-stat:hover,
  .page-about .about-stat:focus-within {
    transform: none;
  }
  .page-about .about-hero__title em {
    transform: none;
  }
}
<<<END>>>