.page-about {
  --about-rail: 200px;
  color: var(--paper);
  overflow-x: hidden;
}

.page-about .about-shell {
  width: 100%;
  max-width: var(--shell);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

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

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding-block: clamp(20px, 4vw, 36px) clamp(36px, 6vw, 76px);
}

.page-about .about-hero__wedge {
  position: absolute;
  top: -70px;
  right: -14%;
  width: min(620px, 80vw);
  height: min(460px, 66vw);
  background: linear-gradient(155deg, rgba(36, 199, 190, 0.16), rgba(255, 106, 42, 0.12) 56%, rgba(13, 26, 35, 0) 74%);
  clip-path: polygon(20% 0, 100% 0, 100% 74%, 0 100%);
  pointer-events: none;
}

.page-about .about-hero .eyebrow {
  position: relative;
  margin: 0;
}

.page-about .about-hero h1 {
  position: relative;
  margin: 14px 0 0;
  max-width: 17ch;
  font-size: clamp(33px, 6.2vw, 74px);
  line-height: 1.04;
  letter-spacing: -0.02em;
  font-weight: 900;
}

.page-about .about-hero .lede {
  position: relative;
  margin: clamp(16px, 2.4vw, 26px) 0 0;
  max-width: 48ch;
  color: var(--ink-300);
  font-size: clamp(15px, 1.6vw, 18px);
  line-height: 1.85;
}

.page-about .about-meta {
  position: relative;
  list-style: none;
  margin: clamp(24px, 4vw, 40px) 0 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 12px 28px;
}

.page-about .about-meta li {
  display: flex;
  align-items: baseline;
  gap: 10px;
  font-size: 13px;
  color: var(--ink-300);
}

.page-about .about-meta .mono {
  font-family: var(--font-mono);
  font-size: 18px;
  color: var(--orange);
  letter-spacing: 0.02em;
}

.page-about .about-hero__note {
  display: none;
}

/* ---------- 主体网格 ---------- */
.page-about .about-body {
  display: block;
  padding-bottom: clamp(48px, 7vw, 96px);
}

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

.page-about .about-rail__label {
  margin: 0 0 14px;
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--ink-500);
}

.page-about .about-rail__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 12px;
}

.page-about .about-rail__list a {
  display: flex;
  align-items: baseline;
  gap: 10px;
  font-size: 14px;
  line-height: 1.4;
  color: var(--ink-300);
  text-decoration: none;
  transition: color 0.18s var(--ease);
}

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

.page-about .about-rail__list .mono {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--ink-500);
}

/* ---------- 章节 ---------- */
.page-about .chapter {
  padding-block: clamp(34px, 5.5vw, 68px);
  border-top: 1px solid var(--line-soft);
}

.page-about .about-flow > .chapter:first-child {
  border-top: 0;
  padding-top: clamp(12px, 2vw, 24px);
}

.page-about .chapter__num {
  display: block;
  margin-bottom: 10px;
  font-family: var(--font-mono);
  font-size: clamp(38px, 6.6vw, 76px);
  line-height: 1;
  letter-spacing: 0.02em;
  color: var(--ink-700);
}

@supports (-webkit-text-stroke: 1px #000) {
  .page-about .chapter__num {
    color: transparent;
    -webkit-text-stroke: 1px var(--ink-500);
  }
}

.page-about .chapter h2 {
  margin: 0 0 clamp(14px, 2vw, 20px);
  max-width: 24ch;
  font-size: clamp(23px, 3.4vw, 38px);
  line-height: 1.16;
  letter-spacing: -0.01em;
  font-weight: 800;
}

.page-about .chapter p {
  margin: 0 0 16px;
  max-width: 64ch;
  color: var(--ink-300);
  font-size: clamp(15px, 1.5vw, 17px);
  line-height: 1.85;
}

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

/* ---------- 图文错位 ---------- */
.page-about .split {
  display: grid;
  gap: clamp(20px, 3.5vw, 36px);
  margin-top: clamp(16px, 2.6vw, 28px);
}

.page-about .split--flip {
  margin-top: clamp(10px, 2vw, 20px);
}

/* ---------- 时间线 ---------- */
.page-about .timeline {
  display: flex;
  gap: 14px;
  margin-top: clamp(16px, 2.6vw, 26px);
  padding: 4px 2px 20px;
  overflow-x: auto;
  scroll-snap-type: x mandatory;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: thin;
  scrollbar-color: var(--ink-700) transparent;
}

.page-about .timeline::-webkit-scrollbar {
  height: 6px;
}

.page-about .timeline::-webkit-scrollbar-track {
  background: var(--line-soft);
  border-radius: var(--pill);
}

.page-about .timeline::-webkit-scrollbar-thumb {
  background: var(--ink-700);
  border-radius: var(--pill);
}

.page-about .tl-item {
  flex: 0 0 min(276px, 80vw);
  scroll-snap-align: start;
  padding: 20px 18px 22px;
  background: var(--ink-800);
  border: 1px solid var(--line-soft);
  border-radius: var(--radius-md);
}

.page-about .tl-item__label {
  margin: 0 0 10px;
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--cyan);
}

.page-about .tl-item h3 {
  margin: 0 0 8px;
  font-size: 17px;
  line-height: 1.35;
  color: var(--paper);
}

.page-about .tl-item p {
  margin: 0;
  font-size: 14px;
  line-height: 1.72;
  color: var(--ink-300);
  max-width: none;
}

/* ---------- 数据能力 ---------- */
.page-about .stats {
  display: grid;
  gap: 12px;
  grid-template-columns: repeat(auto-fit, minmax(142px, 1fr));
  margin: clamp(18px, 2.8vw, 30px) 0 clamp(18px, 2.8vw, 28px);
}

.page-about .stat {
  padding: 16px 16px 18px;
  background: var(--ink-800);
  border: 1px solid var(--line-soft);
  border-radius: var(--radius-md);
}

.page-about .stat__num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(23px, 3.2vw, 33px);
  line-height: 1.1;
  letter-spacing: -0.01em;
  color: var(--paper);
}

.page-about .stat__num--orange {
  color: var(--orange);
}

.page-about .stat__num--cyan {
  color: var(--cyan);
}

.page-about .stat__label {
  display: block;
  margin-top: 8px;
  font-size: 12.5px;
  line-height: 1.55;
  color: var(--ink-300);
}

/* ---------- 认证信息清单 ---------- */
.page-about .cert-list {
  list-style: none;
  margin: clamp(18px, 2.8vw, 30px) 0 0;
  padding: 0;
}

.page-about .cert-item {
  padding: 18px 0;
  border-top: 1px solid var(--line-soft);
}

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

.page-about .cert-item__head {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  margin-bottom: 8px;
}

.page-about .cert-item h3 {
  margin: 0;
  font-size: 17px;
  line-height: 1.4;
  font-weight: 700;
  color: var(--paper);
}

.page-about .cert-item p {
  margin: 0 0 8px;
  font-size: 15px;
  line-height: 1.75;
  color: var(--ink-300);
}

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

.page-about .cert-item a {
  display: inline-block;
  font-size: 14px;
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(36, 199, 190, 0.42);
  padding-bottom: 2px;
  transition: border-color 0.18s var(--ease), color 0.18s var(--ease);
}

.page-about .cert-item a:hover,
.page-about .cert-item a:focus-visible {
  color: var(--paper);
  border-color: var(--paper);
}

/* ---------- 合作生态 ---------- */
.page-about .eco {
  display: grid;
  gap: 12px;
  margin-top: clamp(16px, 2.6vw, 26px);
}

.page-about .eco__item {
  padding: 16px 18px 18px;
  border-radius: var(--radius-sm);
  background: var(--ink-800);
  border-left: 3px solid var(--ink-700);
}

.page-about .eco__item h3 {
  margin: 0 0 6px;
  font-size: 16px;
  line-height: 1.4;
  color: var(--paper);
}

.page-about .eco__item p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.72;
  color: var(--ink-300);
  max-width: none;
}

.page-about .about-award {
  margin-top: clamp(18px, 2.8vw, 28px);
  padding-left: 16px;
  border-left: 3px solid var(--orange);
  font-size: 15px;
  line-height: 1.8;
  color: var(--ink-300);
}

/* ---------- 下一步 ---------- */
.page-about .about-cta {
  margin-top: clamp(30px, 5vw, 56px);
  padding: clamp(22px, 4vw, 40px);
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background: linear-gradient(140deg, var(--ink-800), var(--ink-700));
}

.page-about .about-cta h2 {
  margin: 0 0 12px;
  font-size: clamp(21px, 3vw, 30px);
  line-height: 1.2;
  font-weight: 800;
  color: var(--paper);
}

.page-about .about-cta p {
  margin: 0;
  max-width: 56ch;
  font-size: 15px;
  line-height: 1.8;
  color: var(--ink-300);
}

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

/* ---------- 断点 ---------- */
@media (min-width: 700px) {
  .page-about .split {
    grid-template-columns: minmax(0, 1fr) minmax(0, 0.92fr);
    align-items: start;
  }

  .page-about .split--flip {
    grid-template-columns: minmax(0, 0.92fr) minmax(0, 1fr);
    align-items: start;
  }

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

@media (min-width: 900px) {
  .page-about .about-body {
    display: grid;
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    gap: clamp(32px, 5vw, 72px);
    align-items: start;
  }

  .page-about .about-rail {
    display: block;
    position: sticky;
    top: 96px;
    padding-left: 18px;
    border-left: 1px solid var(--line-soft);
  }
}

@media (min-width: 1100px) {
  .page-about .about-hero__note {
    display: block;
    position: absolute;
    top: 116px;
    right: 0;
    writing-mode: vertical-rl;
    font-size: 12px;
    letter-spacing: 0.2em;
    color: var(--ink-500);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-rail__list a,
  .page-about .cert-item a {
    transition: none;
  }

  .page-about .timeline {
    scroll-behavior: auto;
  }
}
<<<END>>>