.page-about {
  --about-space: 56px;
  --about-rule: 1px solid var(--line);
  color: var(--graphite);
  background: var(--paper);
}

@media (min-width: 768px) {
  .page-about {
    --about-space: 92px;
  }
}

@media (min-width: 1200px) {
  .page-about {
    --about-space: 124px;
  }
}

/* ---------- 面包屑 ---------- */
.page-about .about-crumb {
  padding-top: 22px;
  padding-bottom: 6px;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding: clamp(28px, 5vw, 60px) 0 clamp(44px, 7vw, 88px);
  border-bottom: var(--about-rule);
}

.page-about .about-hero__grid {
  display: grid;
  gap: 28px;
}

.page-about .about-hero__title {
  font-family: var(--font-sans);
  font-weight: 300;
  font-size: clamp(36px, 8.4vw, 82px);
  line-height: 1.06;
  letter-spacing: -0.02em;
  color: var(--ink-900);
  margin: 14px 0 0;
}

.page-about .about-hero__lede {
  font-family: var(--font-serif);
  font-size: clamp(16px, 2.1vw, 20px);
  line-height: 1.68;
  color: var(--ink-700);
  max-width: 32em;
  margin: 0 0 26px;
}

.page-about .about-hero__stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--line);
  border: var(--about-rule);
  margin: 0;
}

.page-about .about-stat {
  background: var(--paper-2);
  padding: 14px 16px 16px;
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.page-about .about-stat dt {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--index-gray);
  margin: 0;
}

.page-about .about-stat dd {
  font-family: var(--font-sans);
  font-weight: 500;
  font-size: 26px;
  line-height: 1.05;
  color: var(--ink-900);
  margin: 0;
}

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, 1fr);
    align-items: end;
    gap: 52px;
  }

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

/* ---------- 通用标题与正文 ---------- */
.page-about .about-h2 {
  font-family: var(--font-sans);
  font-weight: 300;
  font-size: clamp(26px, 4.4vw, 44px);
  line-height: 1.22;
  letter-spacing: -0.01em;
  color: var(--ink-900);
  margin: 0 0 18px;
  max-width: 18em;
}

.page-about .about-prose {
  font-family: var(--font-sans);
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--graphite);
  max-width: 31em;
  margin: 0 0 16px;
}

.page-about .about-sec-head {
  margin-bottom: 8px;
}

.page-about .about-num {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.18em;
  color: var(--amber-500);
  border-top: 2px solid var(--amber-500);
  padding-top: 10px;
  width: 56px;
  margin: 0;
}

/* ---------- 起点 ---------- */
.page-about .about-origin {
  padding: var(--about-space) 0;
}

.page-about .about-origin__grid {
  display: grid;
  gap: 22px;
}

@media (min-width: 900px) {
  .page-about .about-origin__grid {
    grid-template-columns: 140px minmax(0, 1fr);
    gap: 44px;
  }

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

/* ---------- 时间线 ---------- */
.page-about .about-timeline {
  padding: var(--about-space) 0;
  background: var(--paper-2);
  border-top: var(--about-rule);
  border-bottom: var(--about-rule);
}

.page-about .about-years {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 30px 0 26px;
}

.page-about .about-years a {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--ink-700);
  text-decoration: none;
  border: 1px solid var(--line);
  padding: 7px 14px;
  background: var(--paper);
  transition: border-color var(--dur) var(--ease), color var(--dur) var(--ease), background var(--dur) var(--ease);
}

.page-about .about-years a:hover,
.page-about .about-years a:focus-visible {
  color: var(--celadon-ink);
  border-color: var(--celadon-500);
  background: var(--celadon-100);
}

.page-about .about-tl {
  list-style: none;
  margin: 0;
  padding: 0 0 0 26px;
  position: relative;
}

.page-about .about-tl::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 8px;
  bottom: 14px;
  width: 1px;
  background: repeating-linear-gradient(to bottom, var(--indigo-500) 0 7px, transparent 7px 14px);
  opacity: 0.45;
}

.page-about .about-tl__item {
  position: relative;
  padding-bottom: 42px;
  scroll-margin-top: calc(var(--topbar-h) + 28px);
}

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

.page-about .about-tl__dot {
  position: absolute;
  left: -26px;
  top: 6px;
  width: 12px;
  height: 12px;
  background: var(--paper-2);
  border: 1px solid var(--indigo-500);
  clip-path: polygon(0 0, 100% 0, 100% 70%, 70% 100%, 0 100%);
  transition: background var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.page-about .about-tl__item:target .about-tl__dot {
  background: var(--amber-500);
  border-color: var(--amber-500);
}

.page-about .about-tl__year {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--index-gray);
  margin: 0 0 10px;
}

.page-about .about-tl__body h3 {
  font-family: var(--font-sans);
  font-weight: 500;
  font-size: clamp(19px, 2.5vw, 24px);
  line-height: 1.35;
  color: var(--ink-900);
  margin: 0 0 10px;
}

.page-about .about-tl__text {
  font-family: var(--font-sans);
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--graphite);
  max-width: 30em;
  margin: 0;
}

.page-about .about-tl__more {
  display: block;
  font-family: var(--font-serif);
  font-size: 15px;
  line-height: 1.72;
  color: var(--ink-700);
  border-left: 2px solid var(--amber-500);
  padding: 2px 0 2px 14px;
  margin: 14px 0 0;
  max-width: 30em;
}

.page-about .about-tl__more a {
  color: var(--celadon-ink);
  text-decoration: underline;
  text-underline-offset: 3px;
}

@media (hover: hover) and (min-width: 900px) {
  .page-about .about-tl__more {
    max-height: 0;
    opacity: 0;
    overflow: hidden;
    margin-top: 0;
    padding-top: 0;
    padding-bottom: 0;
    transition: max-height 240ms var(--ease), opacity 240ms var(--ease), margin-top 240ms var(--ease), padding 240ms var(--ease);
  }

  .page-about .about-tl__item:hover .about-tl__more,
  .page-about .about-tl__item:focus-within .about-tl__more {
    max-height: 14em;
    opacity: 1;
    margin-top: 14px;
    padding-top: 2px;
    padding-bottom: 2px;
  }
}

/* ---------- 图片 ---------- */
.page-about .about-figure {
  margin: 30px 0 0;
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  height: auto;
  border: var(--about-rule);
  background: var(--ink-900);
  object-fit: cover;
}

.page-about .about-figure__caption {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--index-gray);
  margin-top: 10px;
}

.page-about .about-figure--team {
  max-width: 560px;
  margin: 34px auto 0;
}

.page-about .about-figure--band {
  margin-top: 40px;
}

.page-about .about-figure__caption--dark {
  color: var(--paper);
  opacity: 0.6;
}

/* ---------- 团队 ---------- */
.page-about .about-team {
  padding: var(--about-space) 0;
}

.page-about .about-team__grid {
  display: grid;
  gap: 14px;
  margin-top: 34px;
}

@media (min-width: 880px) {
  .page-about .about-team__grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 20px;
    align-items: start;
  }
}

.page-about .about-team__col {
  background: var(--paper-2);
  border: var(--about-rule);
  border-left: 3px solid var(--ink-700);
  padding: 20px 18px 18px;
  transition: border-color var(--dur) var(--ease), background var(--dur) var(--ease);
}

.page-about .about-team__col[open] {
  border-left-color: var(--amber-500);
  background: #ffffff;
}

.page-about .about-team__col summary {
  cursor: pointer;
  list-style: none;
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto;
  align-items: center;
  gap: 14px;
}

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

.page-about .about-team__col summary:focus-visible {
  outline: 2px solid var(--celadon-500);
  outline-offset: 4px;
}

.page-about .about-team__meta {
  display: grid;
  gap: 5px;
  min-width: 0;
}

.page-about .about-team__idx {
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: 0.14em;
  color: var(--index-gray);
}

.page-about .about-team__meta h3 {
  font-family: var(--font-sans);
  font-weight: 500;
  font-size: 17px;
  line-height: 1.35;
  color: var(--ink-900);
  margin: 0;
}

.page-about .about-team__cue {
  width: 10px;
  height: 10px;
  border-right: 1.5px solid var(--index-gray);
  border-bottom: 1.5px solid var(--index-gray);
  transform: rotate(45deg) translateY(-2px);
  transition: transform var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.page-about .about-team__col[open] .about-team__cue {
  transform: rotate(-135deg) translateY(-2px);
  border-color: var(--amber-500);
}

.page-about .about-ring-wrap {
  position: relative;
  display: inline-grid;
  place-items: center;
  width: 56px;
  height: 56px;
  flex: none;
}

.page-about .about-ring {
  display: block;
  width: 56px;
  height: 56px;
}

.page-about .about-ring__track {
  fill: none;
  stroke: var(--line);
  stroke-width: 6;
}

.page-about .about-ring__fill {
  fill: none;
  stroke-width: 6;
}

.page-about .about-ring__fill--amber {
  stroke: var(--amber-500);
}

.page-about .about-ring__fill--celadon {
  stroke: var(--celadon-500);
}

.page-about .about-ring__fill--indigo {
  stroke: var(--indigo-500);
}

.page-about .about-ring-wrap__num {
  position: absolute;
  font-family: var(--font-mono);
  font-size: 15px;
  color: var(--ink-900);
  letter-spacing: 0.02em;
}

.page-about .about-team__tasks {
  list-style: none;
  margin: 18px 0 0;
  padding: 16px 0 0;
  border-top: 1px dashed var(--line);
}

.page-about .about-team__tasks li {
  position: relative;
  font-family: var(--font-sans);
  font-size: 14px;
  line-height: 1.72;
  color: var(--graphite);
  padding-left: 18px;
  margin-bottom: 9px;
}

.page-about .about-team__tasks li:last-child {
  margin-bottom: 0;
}

.page-about .about-team__tasks li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 10px;
  width: 8px;
  height: 1px;
  background: var(--celadon-500);
}

/* ---------- 访问结构 ---------- */
.page-about .about-reach {
  padding: var(--about-space) 0;
  border-top: var(--about-rule);
}

.page-about .about-reach__grid {
  display: grid;
  gap: 12px;
  margin-top: 28px;
}

@media (min-width: 880px) {
  .page-about .about-reach__grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 24px;
  }
}

.page-about .about-reach__item {
  padding: 26px 22px 24px;
  background: var(--paper-2);
  border: var(--about-rule);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 16px), calc(100% - 16px) 100%, 0 100%);
}

.page-about .about-reach__num {
  font-family: var(--font-sans);
  font-weight: 300;
  font-size: clamp(34px, 6vw, 52px);
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--ink-900);
  margin: 0 0 8px;
}

.page-about .about-reach__label {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--celadon-ink);
  margin: 0 0 14px;
  padding-bottom: 14px;
  border-bottom: 1px solid var(--line);
}

.page-about .about-reach__text {
  font-family: var(--font-sans);
  font-size: 15px;
  line-height: 1.82;
  color: var(--graphite);
  margin: 0;
  max-width: 30em;
}

/* ---------- 稳定性条带 ---------- */
.page-about .about-stable {
  padding: var(--about-space) 0;
  background: var(--ink-900);
  border-top: 4px solid var(--amber-500);
  color: var(--paper);
}

.page-about .about-sec-head--dark {
  margin-bottom: 30px;
}

.page-about .about-eyebrow--dark,
.page-about .about-h2--paper,
.page-about .about-prose--paper {
  color: var(--paper);
}

.page-about .about-eyebrow--dark {
  color: var(--amber-500);
}

.page-about .about-prose--paper {
  opacity: 0.78;
}

.page-about .about-stable__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: rgba(246, 244, 239, 0.16);
  border: 1px solid rgba(246, 244, 239, 0.16);
}

@media (min-width: 720px) {
  .page-about .about-stable__list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 1100px) {
  .page-about .about-stable__list {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

.page-about .about-stable__list li {
  background: var(--ink-900);
  padding: 22px 20px 24px;
  display: grid;
  gap: 8px;
  align-content: start;
}

.page-about .about-stable__num {
  font-family: var(--font-sans);
  font-weight: 300;
  font-size: clamp(26px, 4vw, 36px);
  line-height: 1.05;
  color: var(--amber-500);
  letter-spacing: -0.01em;
}

.page-about .about-stable__label {
  font-family: var(--font-sans);
  font-size: 13.5px;
  line-height: 1.65;
  color: var(--paper);
  opacity: 0.75;
}

/* ---------- 尾部入口 ---------- */
.page-about .about-next {
  padding: clamp(48px, 7vw, 88px) 0;
  background: var(--paper);
  border-top: 1px solid var(--line);
}

.page-about .about-next__title {
  font-family: var(--font-sans);
  font-weight: 300;
  font-size: clamp(24px, 3.6vw, 34px);
  letter-spacing: -0.01em;
  color: var(--ink-900);
  margin: 0 0 22px;
}

.page-about .about-next__links {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--line);
  border: var(--about-rule);
}

@media (min-width: 780px) {
  .page-about .about-next__links {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

.page-about .about-next__links a {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  background: var(--paper-2);
  padding: 18px 20px;
  font-family: var(--font-sans);
  font-size: 15px;
  font-weight: 500;
  color: var(--ink-900);
  text-decoration: none;
  transition: background var(--dur) var(--ease), color var(--dur) var(--ease);
}

.page-about .about-next__links a span {
  font-family: var(--font-mono);
  color: var(--celadon-500);
  transition: transform var(--dur) var(--ease);
}

.page-about .about-next__links a:hover,
.page-about .about-next__links a:focus-visible {
  background: var(--celadon-100);
  color: var(--celadon-ink);
}

.page-about .about-next__links a:hover span,
.page-about .about-next__links a:focus-visible span {
  transform: translateX(4px);
}

@media (prefers-reduced-motion: reduce) {
  .page-about * {
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
  }

  .page-about .about-tl__more {
    max-height: none !important;
    opacity: 1 !important;
    margin-top: 14px !important;
    padding-top: 2px !important;
    padding-bottom: 2px !important;
  }
}
<<<END>>>