.page-about {
  --about-index-w: 200px;
  --about-line-soft: var(--sf-line-soft);
  background: var(--sf-paper);
  color: var(--sf-text);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  isolation: isolate;
  overflow: hidden;
  background: var(--sf-ink-green);
  color: var(--sf-on-dark);
  padding: clamp(20px, 3.5vw, 36px) 0 var(--sf-space);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  z-index: -1;
  top: -34%;
  right: -18%;
  width: min(760px, 92%);
  aspect-ratio: 1;
  transform: rotate(18deg);
  background:
    linear-gradient(135deg, rgba(255, 107, 44, .17), transparent 62%),
    radial-gradient(circle at 68% 30%, rgba(198, 255, 74, .10), transparent 58%);
  pointer-events: none;
}

.page-about .about-hero__grid {
  display: grid;
  gap: clamp(24px, 4vw, 44px);
  margin-top: clamp(16px, 3vw, 30px);
}

.page-about .about-hero__figure {
  margin: 0;
  min-width: 0;
}

.page-about .about-hero__figure .sf-media {
  aspect-ratio: 7 / 5;
  border: 1px solid var(--sf-line-dark);
  border-radius: var(--sf-radius);
}

.page-about .about-hero__figure .sf-media__caption {
  margin-top: 10px;
  font-family: var(--sf-font-mono);
  font-size: 11px;
  letter-spacing: .08em;
  line-height: 1.6;
  color: var(--sf-on-dark-muted);
}

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

.page-about .about-hero__title {
  margin: clamp(12px, 2vw, 18px) 0 0;
  font-family: var(--sf-font-head);
  font-weight: 800;
  font-size: clamp(29px, 6.2vw, 58px);
  line-height: 1.06;
  letter-spacing: -.025em;
  color: #FFFFFF;
}

.page-about .about-hero__lede {
  margin: clamp(14px, 2vw, 20px) 0 0;
  max-width: 54ch;
  font-size: clamp(15px, 1.7vw, 17px);
  line-height: 1.85;
  color: var(--sf-on-dark-muted);
}

.page-about .about-hero__facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: clamp(22px, 3vw, 34px) 0 0;
  padding: 0;
  list-style: none;
  background: var(--sf-line);
  border-top: 1px solid var(--sf-line);
  border-bottom: 1px solid var(--sf-line);
}

.page-about .about-fact {
  background: var(--sf-ink-green);
  padding: 14px clamp(12px, 2vw, 18px);
}

.page-about .about-fact__num {
  display: block;
  font-family: var(--sf-font-mono);
  font-size: clamp(22px, 3vw, 30px);
  font-weight: 700;
  line-height: 1.1;
  color: var(--sf-orange);
}

.page-about .about-fact__num small {
  font-size: .52em;
  margin-left: 3px;
  color: var(--sf-on-dark-muted);
  font-weight: 500;
}

.page-about .about-fact__label {
  display: block;
  margin-top: 6px;
  font-size: 12px;
  letter-spacing: .04em;
  color: var(--sf-on-dark-muted);
}

/* ---------- 主体分屏 ---------- */
.page-about .about-body {
  padding: clamp(30px, 6vw, 76px) 0 clamp(40px, 7vw, 92px);
}

.page-about .about-body__grid {
  display: grid;
  gap: clamp(22px, 4vw, 52px);
}

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

.page-about .about-index {
  min-width: 0;
  align-self: start;
  border-top: 1px solid var(--about-line-soft);
  padding-top: 12px;
}

.page-about .about-index__title {
  margin: 0 0 8px;
  font-family: var(--sf-font-mono);
  font-size: 11px;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--sf-muted);
}

.page-about .about-index__list {
  display: flex;
  gap: 4px;
  margin: 0;
  padding: 0 0 4px;
  list-style: none;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: thin;
}

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

.page-about .about-index__link {
  display: block;
  padding: 7px 11px;
  font-size: 13px;
  line-height: 1.4;
  white-space: nowrap;
  text-decoration: none;
  color: var(--sf-muted);
  border-bottom: 2px solid transparent;
  transition: color .2s var(--sf-ease), border-color .2s var(--sf-ease), background-color .2s var(--sf-ease);
}

.page-about .about-index__link:hover {
  color: var(--sf-text);
  background: var(--sf-bone);
}

.page-about .about-index__link[data-active="true"] {
  color: var(--sf-text);
  font-weight: 700;
  border-bottom-color: var(--sf-orange);
}

/* ---------- 章节 ---------- */
.page-about .about-sec {
  padding: clamp(28px, 5vw, 54px) 0;
}

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

.page-about .about-sec + .about-sec {
  border-top: 1px solid var(--about-line-soft);
}

.page-about .about-sec__head {
  display: flex;
  align-items: baseline;
  gap: clamp(10px, 2vw, 16px);
  margin-bottom: clamp(14px, 2vw, 22px);
}

.page-about .about-sec__num {
  flex: none;
  font-family: var(--sf-font-mono);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .12em;
  color: var(--sf-orange);
}

.page-about .about-sec__title {
  margin: 0;
  font-family: var(--sf-font-head);
  font-weight: 800;
  font-size: clamp(22px, 3.6vw, 33px);
  line-height: 1.16;
  letter-spacing: -.015em;
  color: var(--sf-text);
}

.page-about .about-text {
  max-width: 66ch;
  margin: 0;
  font-size: clamp(15px, 1.55vw, 17px);
  line-height: 1.85;
  color: var(--sf-text);
}

.page-about .about-text + .about-text {
  margin-top: 14px;
}

.page-about .about-text--tight {
  margin-top: clamp(16px, 2.6vw, 22px);
}

.page-about .about-quote {
  margin: clamp(18px, 3vw, 28px) 0 0;
  padding: clamp(16px, 2.6vw, 22px) clamp(16px, 3vw, 26px);
  border-left: 3px solid var(--sf-orange);
  background: var(--sf-bone);
  font-family: var(--sf-font-head);
  font-weight: 700;
  font-size: clamp(17px, 2.3vw, 21px);
  line-height: 1.55;
  color: var(--sf-text);
}

/* ---------- 方法三步 ---------- */
.page-about .about-method {
  display: grid;
  gap: 0;
  margin: clamp(18px, 3vw, 26px) 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-method__item {
  padding: 16px 0;
}

.page-about .about-method__item + .about-method__item {
  border-top: 1px solid var(--about-line-soft);
}

.page-about .about-method__num {
  margin: 0;
  font-family: var(--sf-font-mono);
  font-size: 11px;
  letter-spacing: .18em;
  color: var(--sf-orange);
}

.page-about .about-method__title {
  margin: 8px 0 6px;
  font-family: var(--sf-font-head);
  font-weight: 700;
  font-size: clamp(17px, 2vw, 20px);
  color: var(--sf-text);
}

.page-about .about-method__text {
  margin: 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--sf-muted);
}

.page-about .about-figure {
  margin: clamp(20px, 3.2vw, 30px) 0 0;
}

.page-about .about-figure .sf-media {
  aspect-ratio: 3 / 2;
  border: 1px solid var(--about-line-soft);
  border-radius: var(--sf-radius);
}

.page-about .about-figure .sf-media__caption {
  margin-top: 10px;
  font-family: var(--sf-font-mono);
  font-size: 11px;
  letter-spacing: .06em;
  line-height: 1.6;
  color: var(--sf-muted);
}

/* ---------- 时间轴 ---------- */
.page-about .about-timeline {
  position: relative;
  margin: clamp(20px, 3vw, 30px) 0 0;
  padding: 0 0 0 28px;
  list-style: none;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 7px;
  top: 8px;
  bottom: 12px;
  width: 1px;
  background: linear-gradient(180deg, var(--sf-orange), var(--sf-line-soft));
}

.page-about .about-timeline__item {
  position: relative;
  padding-bottom: clamp(18px, 2.8vw, 26px);
}

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

.page-about .about-timeline__node {
  position: absolute;
  left: -28px;
  top: 8px;
  width: 15px;
  height: 15px;
  background: var(--sf-paper);
  border: 2px solid var(--sf-pine);
  transform: rotate(45deg);
  transition: border-color .2s var(--sf-ease), background-color .2s var(--sf-ease);
}

.page-about .about-timeline__item:hover .about-timeline__node,
.page-about .about-timeline__item:focus-within .about-timeline__node {
  border-color: var(--sf-orange);
  background: var(--sf-orange);
}

.page-about .about-timeline__card {
  margin-inline: -10px;
  padding: 8px 10px 10px;
  border-top: 1px solid var(--about-line-soft);
  transition: background-color .2s var(--sf-ease);
}

.page-about .about-timeline__item:hover .about-timeline__card,
.page-about .about-timeline__item:focus-within .about-timeline__card {
  background: var(--sf-bone);
}

.page-about .about-timeline__stage {
  margin: 0;
  font-family: var(--sf-font-mono);
  font-size: 11px;
  letter-spacing: .18em;
  color: var(--sf-muted);
}

.page-about .about-timeline__title {
  margin: 6px 0 4px;
  font-family: var(--sf-font-head);
  font-weight: 700;
  font-size: clamp(17px, 2.1vw, 21px);
  color: var(--sf-text);
}

.page-about .about-timeline__text {
  margin: 0;
  max-width: 62ch;
  font-size: 14px;
  line-height: 1.75;
  color: var(--sf-muted);
}

/* ---------- 团队（深色带） ---------- */
.page-about .about-sec.about-sec--ink {
  border-top: 1px solid var(--sf-pine);
  border-bottom: 1px solid var(--sf-pine);
  background: var(--sf-deep-forest);
  color: var(--sf-on-dark);
  margin-inline: calc(var(--sf-gutter) * -1);
  padding-inline: var(--sf-gutter);
  padding-block: clamp(30px, 5vw, 58px);
}

.page-about .about-sec--ink .about-sec__title {
  color: var(--sf-on-dark);
}

.page-about .about-sec--ink .about-sec__num {
  color: var(--sf-lime);
}

.page-about .about-sec--ink .about-text {
  color: var(--sf-on-dark-muted);
}

.page-about .about-team__stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: clamp(18px, 3vw, 26px) 0 0;
  padding: 0;
  list-style: none;
  background: var(--sf-line-dark);
  border-top: 1px solid var(--sf-line-dark);
  border-bottom: 1px solid var(--sf-line-dark);
}

.page-about .about-team__stat {
  background: var(--sf-deep-forest);
  padding: 14px clamp(10px, 2vw, 18px);
}

.page-about .about-team__num {
  display: block;
  font-family: var(--sf-font-mono);
  font-size: clamp(22px, 3vw, 30px);
  font-weight: 700;
  line-height: 1.1;
  color: var(--sf-orange);
}

.page-about .about-team__label {
  display: block;
  margin-top: 6px;
  font-size: 12px;
  letter-spacing: .04em;
  color: var(--sf-on-dark-muted);
}

.page-about .about-flow {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: clamp(16px, 2.6vw, 22px) 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-flow__step {
  padding: 8px 16px 8px 14px;
  font-size: 13px;
  line-height: 1.4;
  color: var(--sf-on-dark);
  background: rgba(198, 255, 74, .08);
  border: 1px solid var(--sf-line-dark);
  clip-path: polygon(0 0, 100% 0, calc(100% - 9px) 100%, 0 100%);
}

/* ---------- 合作生态 ---------- */
.page-about .about-partners {
  display: grid;
  gap: 1px;
  margin: clamp(18px, 3vw, 26px) 0 0;
  padding: 0;
  list-style: none;
  background: var(--about-line-soft);
  border-top: 1px solid var(--about-line-soft);
  border-bottom: 1px solid var(--about-line-soft);
}

.page-about .about-partners__item {
  background: var(--sf-paper);
  padding: clamp(16px, 2.4vw, 22px);
  transition: background-color .2s var(--sf-ease), transform .2s var(--sf-ease);
}

.page-about .about-partners__item:hover {
  background: var(--sf-bone);
  transform: translateX(3px);
}

.page-about .about-partners__title {
  margin: 10px 0 8px;
  font-family: var(--sf-font-head);
  font-weight: 700;
  font-size: clamp(17px, 2vw, 20px);
  color: var(--sf-text);
}

.page-about .about-partners__text {
  margin: 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--sf-muted);
}

/* ---------- 承诺与联系 ---------- */
.page-about .about-sec.about-sec--commit {
  position: relative;
  overflow: hidden;
  border-top: 0;
  border-bottom: 0;
  background: var(--sf-ink-green);
  color: var(--sf-on-dark);
  margin-inline: calc(var(--sf-gutter) * -1);
  margin-bottom: calc(clamp(40px, 7vw, 92px) * -1);
  padding-inline: var(--sf-gutter);
  padding-block: clamp(32px, 5.5vw, 62px);
}

.page-about .about-sec--commit .about-sec__title {
  color: #FFFFFF;
}

.page-about .about-sec--commit .about-sec__num {
  color: var(--sf-lime);
}

.page-about .about-sec--commit .about-text {
  color: var(--sf-on-dark-muted);
}

.page-about .about-sec--commit::after {
  content: "";
  position: absolute;
  left: -8%;
  bottom: -46%;
  width: min(520px, 70%);
  aspect-ratio: 1;
  transform: rotate(-24deg);
  background: linear-gradient(115deg, rgba(255, 107, 44, .16), transparent 62%);
  pointer-events: none;
}

.page-about .about-actions {
  position: relative;
  z-index: 1;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: clamp(20px, 3vw, 28px);
}

.page-about .about-contact {
  position: relative;
  z-index: 1;
  display: grid;
  gap: 10px;
  max-width: 46ch;
  margin-top: clamp(22px, 3vw, 32px);
  padding-top: 16px;
  border-top: 1px solid var(--sf-line-dark);
}

.page-about .about-contact__row {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 4px 12px;
  margin: 0;
}

.page-about .about-contact__label {
  flex: none;
  min-width: 64px;
  font-family: var(--sf-font-mono);
  font-size: 11px;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--sf-steel);
}

.page-about .about-contact__value {
  font-family: var(--sf-font-mono);
  font-size: 14px;
  letter-spacing: .02em;
  color: var(--sf-on-dark);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color .2s var(--sf-ease);
}

.page-about a.about-contact__value:hover {
  border-bottom-color: var(--sf-orange);
}

.page-about .about-contact__note {
  margin: 0;
  font-size: 13px;
  line-height: 1.7;
  color: var(--sf-on-dark-muted);
}

/* ---------- 响应式 ---------- */
@media (min-width: 560px) {
  .page-about .about-hero__facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .about-team__stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

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

  .page-about .about-method__item {
    padding: 0 clamp(0px, 1.6vw, 20px);
  }

  .page-about .about-method__item:first-child {
    padding-left: 0;
  }

  .page-about .about-method__item:last-child {
    padding-right: 0;
  }

  .page-about .about-method__item + .about-method__item {
    border-top: 0;
    border-left: 1px solid var(--about-line-soft);
  }

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

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
    align-items: end;
    gap: clamp(28px, 4vw, 52px);
  }

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

@media (min-width: 1000px) {
  .page-about .about-body__grid {
    grid-template-columns: var(--about-index-w) minmax(0, 1fr);
  }

  .page-about .about-index {
    position: sticky;
    top: clamp(64px, 10vh, 108px);
    border-top: 0;
    padding-top: 0;
  }

  .page-about .about-index__list {
    display: block;
    overflow-x: visible;
    border-left: 1px solid var(--about-line-soft);
    padding-bottom: 0;
  }

  .page-about .about-index__link {
    margin-left: -1px;
    padding: 9px 0 9px 14px;
    white-space: normal;
    border-bottom: 0;
    border-left: 2px solid transparent;
  }

  .page-about .about-index__link:hover {
    background: rgba(255, 107, 44, .07);
  }

  .page-about .about-index__link[data-active="true"] {
    border-left-color: var(--sf-orange);
    border-bottom-color: transparent;
    background: rgba(255, 107, 44, .07);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-timeline__card,
  .page-about .about-timeline__node,
  .page-about .about-partners__item,
  .page-about .about-index__link {
    transition: none;
  }
}
<<<END>>>