.page-about {
  --about-rail-w: 208px;
  --about-stack-gap: clamp(20px, 3.4vw, 44px);
  --about-paper-edge: 0 6px 0 -1px var(--paper), 6px 6px 0 0 var(--printline);
  --about-ink-soft: rgba(244, 239, 230, 0.74);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding-top: calc(var(--header-total) + 26px);
  padding-bottom: clamp(40px, 6vw, 72px);
  background:
    radial-gradient(120% 92% at 86% 6%, rgba(255, 90, 31, 0.13), transparent 62%),
    var(--paper);
  border-bottom: var(--edge);
  overflow: hidden;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image: linear-gradient(to right, rgba(74, 79, 75, 0.07) 1px, transparent 1px);
  background-size: 72px 100%;
  pointer-events: none;
}

.page-about .about-hero > .container {
  position: relative;
  z-index: 1;
}

.page-about .about-hero__grid {
  display: grid;
  gap: clamp(28px, 5vw, 56px);
  margin-top: 22px;
}

.page-about .about-hero h1 {
  margin: 14px 0 0;
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: clamp(30px, 6.6vw, 54px);
  line-height: 1.18;
  letter-spacing: -0.01em;
  color: var(--charcoal);
  max-width: 18ch;
}

.page-about .about-lead {
  margin: 20px 0 0;
  max-width: 42em;
  font-size: 16px;
  line-height: 1.78;
  color: var(--stone);
}

.page-about .hero-stats {
  list-style: none;
  margin: 30px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--printline);
  border: var(--edge);
}

.page-about .hero-stats li {
  display: flex;
  flex-direction: column;
  gap: 5px;
  padding: 16px 14px;
  background: var(--paper);
}

.page-about .hero-stats__num {
  font-family: var(--font-mono);
  font-size: clamp(24px, 4.6vw, 34px);
  font-weight: 700;
  line-height: 1.05;
  letter-spacing: -0.02em;
  color: var(--signal);
}

.page-about .hero-stats__label {
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--stone);
}

.page-about .about-hero__media {
  margin: 0;
  border: var(--edge);
  background: var(--ink);
  box-shadow: 0 22px 42px -34px rgba(18, 18, 18, 0.6);
}

.page-about .about-hero__media img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 8 / 5;
  object-fit: cover;
}

.page-about .about-hero__media figcaption {
  margin: 0;
  padding: 10px 14px;
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--stone);
  background: var(--paper);
  border-top: var(--edge);
}

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, 0.85fr);
    align-items: start;
    gap: clamp(36px, 5vw, 64px);
    margin-top: 30px;
  }
}

@media (min-width: 620px) {
  .page-about .hero-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

/* ---------- 主体骨架 ---------- */
.page-about .about-shell {
  display: grid;
  gap: var(--about-stack-gap);
  padding-top: clamp(40px, 6vw, 76px);
  padding-bottom: clamp(48px, 7vw, 96px);
}

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

@media (min-width: 1000px) {
  .page-about .about-shell {
    grid-template-columns: var(--about-rail-w) minmax(0, 1fr);
    gap: clamp(32px, 4.4vw, 64px);
    align-items: start;
  }

  .page-about .about-rail {
    display: block;
    position: sticky;
    top: calc(var(--header-total) + 28px);
    align-self: start;
  }
}

.page-about .rail-nav__title {
  margin: 0 0 12px;
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--stone);
}

.page-about .rail-nav__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 2px;
}

.page-about .rail-nav__list a {
  display: block;
  padding: 7px 10px 7px 12px;
  border-left: 2px solid transparent;
  font-size: 14px;
  line-height: 1.5;
  color: var(--stone);
  text-decoration: none;
  transition: color 180ms var(--ease), border-color 180ms var(--ease), background 180ms var(--ease);
}

.page-about .rail-nav__list a:hover {
  color: var(--charcoal);
  background: rgba(222, 213, 198, 0.4);
}

.page-about .rail-nav__list a.is-active {
  color: var(--charcoal);
  font-weight: 700;
  border-left-color: var(--signal);
  background: rgba(255, 90, 31, 0.08);
}

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

@media (min-width: 1000px) {
  .page-about .rail-scale {
    display: block;
    position: relative;
    margin-top: 30px;
    padding-left: 18px;
  }

  .page-about .rail-scale::before {
    content: "";
    position: absolute;
    left: 3px;
    top: 4px;
    bottom: 4px;
    width: 2px;
    background: linear-gradient(180deg, var(--signal) 0%, var(--terracotta) 34%, var(--printline) 100%);
  }

  .page-about .rail-scale__list {
    list-style: none;
    margin: 0;
    padding: 0;
    display: grid;
    gap: 15px;
  }

  .page-about .rail-scale__list li {
    position: relative;
    font-family: var(--font-mono);
    font-size: 11px;
    letter-spacing: 0.1em;
    color: var(--stone);
  }

  .page-about .rail-scale__list li::before {
    content: "";
    position: absolute;
    left: -18px;
    top: 50%;
    width: 8px;
    height: 8px;
    transform: translateY(-50%);
    border-radius: 50%;
    background: var(--paper);
    border: 2px solid var(--printline);
  }

  .page-about .rail-scale__list li:first-child::before {
    background: var(--signal);
    border-color: var(--signal);
  }
}

/* ---------- 区块通用 ---------- */
.page-about .about-block {
  scroll-margin-top: calc(var(--header-total) + 24px);
}

.page-about .about-block + .about-block {
  margin-top: clamp(40px, 6vw, 72px);
  padding-top: clamp(34px, 5vw, 56px);
  border-top: var(--edge);
}

.page-about .about-kicker {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin: 0 0 12px;
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.16em;
  color: var(--terracotta);
}

.page-about .about-kicker .num {
  font-family: var(--font-mono);
  color: var(--signal);
}

.page-about .about-block h2 {
  margin: 0;
  max-width: 20ch;
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: clamp(24px, 4.2vw, 38px);
  line-height: 1.24;
  letter-spacing: -0.01em;
  color: var(--charcoal);
}

.page-about .about-block__sub {
  margin: 12px 0 0;
  font-size: 13px;
  letter-spacing: 0.05em;
  color: var(--stone);
}

.page-about .prose {
  margin-top: 20px;
  max-width: 44em;
}

.page-about .prose p {
  margin: 0 0 14px;
  font-size: 16px;
  line-height: 1.78;
  color: var(--charcoal);
}

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

/* ---------- 团队角色卡 ---------- */
.page-about .role-cards {
  list-style: none;
  margin: 26px 0 0;
  padding: 0;
  display: grid;
  gap: 12px;
}

.page-about .role-card {
  padding: 20px 18px 22px;
  background: var(--paper);
  border: var(--edge);
  border-top: 3px solid var(--signal);
  box-shadow: var(--shadow-card);
}

.page-about .role-card:nth-child(2) {
  border-top-color: var(--pitch);
}

.page-about .role-card:nth-child(3) {
  border-top-color: var(--amber);
}

.page-about .role-card__num {
  display: block;
  font-family: var(--font-mono);
  font-size: 40px;
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--charcoal);
}

.page-about .role-card h3 {
  margin: 12px 0 8px;
  font-family: var(--font-sans);
  font-size: 17px;
  font-weight: 700;
  color: var(--charcoal);
}

.page-about .role-card p {
  margin: 0;
  font-size: 14px;
  line-height: 1.74;
  color: var(--stone);
}

@media (min-width: 780px) {
  .page-about .role-cards {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 14px;
  }
}

/* ---------- 筛选与时间线 ---------- */
.page-about .timeline-wrap {
  margin-top: 22px;
}

.page-about .filter-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.page-about .filter-btn {
  appearance: none;
  padding: 7px 15px;
  border: var(--edge);
  border-radius: 999px;
  background: transparent;
  color: var(--stone);
  font-family: var(--font-sans);
  font-size: 13px;
  letter-spacing: 0.06em;
  cursor: pointer;
  transition: background 160ms var(--ease), color 160ms var(--ease), border-color 160ms var(--ease);
}

.page-about .filter-btn:hover {
  border-color: var(--stone);
  color: var(--charcoal);
}

.page-about .filter-btn[aria-pressed="true"] {
  background: var(--charcoal);
  border-color: var(--charcoal);
  color: var(--paper);
}

.page-about .timeline {
  display: grid;
  gap: 14px;
  margin-top: 20px;
}

.page-about .mile {
  position: relative;
  background: var(--paper);
  border: var(--edge);
  box-shadow: var(--about-paper-edge), 0 16px 30px -28px rgba(18, 18, 18, 0.7);
  transition: transform 200ms var(--ease);
}

.page-about .mile:hover {
  transform: translate(-2px, -2px);
}

.page-about .mile__summary {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 8px 14px;
  padding: 16px 18px;
  cursor: pointer;
  list-style: none;
}

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

.page-about .mile__summary::after {
  content: "+";
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 16px;
  line-height: 1;
  color: var(--stone);
  transition: color 180ms var(--ease);
}

.page-about .mile[open] .mile__summary {
  border-bottom: var(--edge);
}

.page-about .mile[open] .mile__summary::after {
  content: "–";
  color: var(--signal);
}

.page-about .mile__year {
  font-family: var(--font-mono);
  font-size: 15px;
  font-weight: 700;
  letter-spacing: 0.02em;
  color: var(--signal);
}

.page-about .mile__title {
  flex: 1 1 auto;
  font-size: 16px;
  font-weight: 700;
  color: var(--charcoal);
}

.page-about .mile__body {
  padding: 16px 18px 20px;
}

.page-about .mile__body p {
  margin: 0;
  max-width: 60ch;
  font-size: 14.5px;
  line-height: 1.76;
  color: var(--stone);
}

/* ---------- 图版 ---------- */
.page-about .about-figure {
  margin: 26px 0 0;
  padding: 8px;
  background: var(--ink);
  border: 1px solid rgba(222, 213, 198, 0.16);
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 3 / 2;
  object-fit: cover;
}

.page-about .about-figure figcaption {
  margin-top: 8px;
  padding: 0 2px 4px;
  font-size: 12px;
  letter-spacing: 0.05em;
  color: var(--about-ink-soft);
}

.page-about .about-figure--wide img {
  aspect-ratio: 4 / 3;
}

/* ---------- 流程四步 ---------- */
.page-about .flow-steps {
  list-style: none;
  margin: 26px 0 0;
  padding: 0;
  display: grid;
  gap: 12px;
}

.page-about .flow-step {
  position: relative;
  padding: 20px 18px 22px;
  background: var(--ink);
  border: 1px solid rgba(222, 213, 198, 0.16);
}

.page-about .flow-step::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 3px;
  background: var(--signal);
}

.page-about .flow-step__idx {
  display: block;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.12em;
  color: var(--amber);
}

.page-about .flow-step h3 {
  margin: 10px 0 8px;
  font-size: 19px;
  font-weight: 700;
  color: var(--paper);
}

.page-about .flow-step p {
  margin: 0;
  font-size: 14px;
  line-height: 1.74;
  color: var(--about-ink-soft);
}

@media (min-width: 700px) {
  .page-about .flow-steps {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 14px;
  }
}

@media (min-width: 1080px) {
  .page-about .flow-steps {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 16px;
  }

  .page-about .flow-step:not(:last-child)::after {
    content: "";
    position: absolute;
    top: 44px;
    right: -9px;
    width: 18px;
    height: 1px;
    background: repeating-linear-gradient(90deg, var(--stone) 0 3px, transparent 3px 7px);
  }
}

/* ---------- 合作与资质 ---------- */
.page-about .partner-grid {
  display: grid;
  gap: 14px;
  margin-top: 26px;
}

.page-about .partner-card {
  padding: 22px 20px;
  background: var(--paper);
  border: var(--edge);
}

.page-about .partner-card:nth-child(2) {
  background: rgba(110, 139, 107, 0.16);
}

.page-about .partner-card h3 {
  margin: 0 0 10px;
  font-size: 17px;
  font-weight: 700;
  color: var(--charcoal);
}

.page-about .partner-card p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.76;
  color: var(--stone);
}

.page-about .cred-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 11px;
}

.page-about .cred-list li {
  position: relative;
  padding-left: 16px;
  font-size: 14.5px;
  line-height: 1.66;
  color: var(--stone);
}

.page-about .cred-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 9px;
  width: 6px;
  height: 6px;
  background: var(--pitch);
}

.page-about .cred-list .num {
  font-family: var(--font-mono);
  font-weight: 700;
  color: var(--charcoal);
}

@media (min-width: 860px) {
  .page-about .partner-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

/* ---------- 三类用户 ---------- */
.page-about .user-cards {
  display: grid;
  gap: 14px;
  margin-top: 26px;
}

.page-about .user-card {
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: 24px 20px 20px;
  background: var(--paper);
  border: var(--edge);
}

.page-about .user-card h3 {
  margin: 0;
  font-family: var(--font-serif);
  font-size: 21px;
  font-weight: 700;
  color: var(--charcoal);
}

.page-about .user-card p {
  flex: 1 1 auto;
  margin: 0;
  font-size: 14.5px;
  line-height: 1.76;
  color: var(--stone);
}

.page-about .user-card__link {
  align-self: flex-start;
  padding-bottom: 2px;
  border-bottom: 1px solid currentColor;
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--signal);
  text-decoration: none;
}

.page-about .user-card__link:hover {
  color: var(--terracotta);
}

@media (min-width: 880px) {
  .page-about .user-cards {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    padding-bottom: 38px;
  }

  .page-about .user-card:nth-child(2) {
    transform: translateY(18px);
  }

  .page-about .user-card:nth-child(3) {
    transform: translateY(36px);
  }
}

/* ---------- 联系 ---------- */
.page-about .reach-grid {
  display: grid;
  gap: 26px;
  margin-top: 26px;
}

.page-about .reach-main p {
  margin: 0 0 20px;
  font-size: 15px;
  line-height: 1.8;
  color: var(--stone);
}

.page-about .reach-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.page-about .reach-list {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: var(--edge);
}

.page-about .reach-list li {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 6px 12px;
  padding: 14px 0;
  border-bottom: var(--edge);
}

.page-about .reach-list__label {
  flex: 0 0 96px;
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--stone);
}

.page-about .reach-list__value {
  flex: 1 1 auto;
  min-width: 0;
  font-size: 15px;
  font-weight: 700;
  color: var(--charcoal);
  word-break: break-word;
}

.page-about .reach-list__value.num {
  font-family: var(--font-mono);
}

.page-about .copy-btn {
  flex: 0 0 auto;
  padding: 4px 12px;
  border: var(--edge);
  border-radius: 999px;
  background: transparent;
  color: var(--stone);
  font-family: var(--font-sans);
  font-size: 12px;
  letter-spacing: 0.06em;
  cursor: pointer;
  transition: color 160ms var(--ease), border-color 160ms var(--ease);
}

.page-about .copy-btn:hover {
  border-color: var(--signal);
  color: var(--signal);
}

.page-about .reach-note {
  margin: 22px 0 0;
  padding: 14px 16px;
  border-left: 3px solid var(--amber);
  background: rgba(255, 176, 32, 0.1);
  font-size: 13px;
  line-height: 1.72;
  color: var(--stone);
}

@media (min-width: 860px) {
  .page-about .reach-grid {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    gap: 44px;
    align-items: start;
  }
}
<<<END>>>