.page-about {
  --about-line: 1px solid rgba(16, 25, 20, .14);
  --about-line-soft: 1px solid rgba(16, 25, 20, .08);
  --about-line-light: 1px solid rgba(245, 242, 233, .18);
  --about-muted: rgba(16, 25, 20, .66);
  --about-paper: #FFFDF7;
  background: var(--board);
  color: var(--ink);
  font-family: var(--font-body);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding: 26px 0 50px;
  overflow: hidden;
  color: var(--board);
  background:
    radial-gradient(120% 90% at 92% -10%, rgba(217, 119, 46, .34), transparent 62%),
    var(--green-deep);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image: repeating-linear-gradient(90deg, rgba(245, 242, 233, .055) 0 1px, transparent 1px 88px);
}

.page-about .about-hero__inner {
  position: relative;
  z-index: 1;
}

.page-about .about-hero .breadcrumb {
  margin: 0 0 26px;
}

.page-about .about-hero .breadcrumb__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin: 0;
  padding: 0;
  list-style: none;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .07em;
}

.page-about .about-hero .breadcrumb__link {
  color: rgba(245, 242, 233, .7);
  text-decoration: none;
  transition: color var(--dur-1) var(--ease);
}

.page-about .about-hero .breadcrumb__link:hover,
.page-about .about-hero .breadcrumb__link:focus-visible {
  color: var(--amber-soft);
}

.page-about .about-hero .breadcrumb__sep,
.page-about .about-hero .breadcrumb__item[aria-current="page"] {
  color: rgba(245, 242, 233, .5);
}

.page-about .about-hero__grid {
  display: grid;
  gap: 30px;
}

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

.page-about .about-hero h1 {
  margin: 14px 0 0;
  max-width: 20ch;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: clamp(32px, 8.4vw, 42px);
  line-height: 1.18;
  letter-spacing: .01em;
  color: var(--board);
}

.page-about .about-hero__intro {
  margin: 18px 0 0;
  max-width: 48ch;
  font-size: 15.5px;
  line-height: 1.85;
  color: rgba(245, 242, 233, .82);
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 26px;
}

.page-about .about-hero__board {
  padding: 18px 18px 20px;
  border: var(--about-line-light);
  background: rgba(245, 242, 233, .06);
}

.page-about .about-hero__board-title {
  margin: 0 0 16px;
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: .2em;
  color: rgba(245, 242, 233, .5);
}

.page-about .about-hero__board dl {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px 14px;
  margin: 0;
}

.page-about .about-hero__board dt {
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: .1em;
  color: rgba(245, 242, 233, .55);
}

.page-about .about-hero__board dd {
  margin: 5px 0 0;
  font-size: 13px;
  color: rgba(245, 242, 233, .82);
}

.page-about .about-hero__board .num {
  font-family: var(--font-mono);
  font-size: 23px;
  line-height: 1.1;
  color: var(--amber-soft);
}

/* ---------- 通用文本 ---------- */
.page-about .eyebrow {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .18em;
  color: var(--green-mid);
}

.page-about h2 {
  margin: 12px 0 0;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: clamp(25px, 5.6vw, 34px);
  line-height: 1.3;
  color: var(--ink);
}

.page-about .about-copy {
  margin: 14px 0 0;
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--about-muted);
}

/* ---------- 图片 ---------- */
.page-about .about-figure {
  margin: 0;
  overflow: hidden;
  border: var(--about-line);
  background: var(--about-paper);
  box-shadow: var(--shadow-1);
}

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

.page-about .about-figure figcaption {
  padding: 10px 14px;
  border-top: var(--about-line);
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .06em;
  color: var(--about-muted);
}

/* ---------- 起点 ---------- */
.page-about .about-origin {
  padding: 46px 0 50px;
  background: var(--board);
}

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

.page-about .about-facts {
  display: grid;
  margin: 24px 0 0;
  padding: 0;
  list-style: none;
  border-top: var(--about-line);
}

.page-about .about-facts li {
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding: 11px 0;
  border-bottom: var(--about-line);
  font-size: 14px;
  line-height: 1.6;
  color: var(--ink);
}

.page-about .about-facts .num {
  flex: 0 0 auto;
  min-width: 62px;
  font-family: var(--font-mono);
  font-size: 18px;
  color: var(--green-mid);
}

/* ---------- 时间轴 ---------- */
.page-about .about-timeline {
  padding: 46px 0 52px;
  background: var(--moss);
  border-top: var(--about-line-soft);
  border-bottom: var(--about-line-soft);
}

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

.page-about .tl-index__title {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: .2em;
  color: rgba(16, 25, 20, .48);
}

.page-about .tl-index__list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .tl-index__link {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  min-height: 44px;
  padding: 0 13px;
  border: var(--about-line);
  border-radius: var(--radius);
  background: rgba(255, 253, 247, .72);
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: .04em;
  color: var(--ink);
  text-decoration: none;
  transition: background var(--dur-1) var(--ease), color var(--dur-1) var(--ease), border-color var(--dur-1) var(--ease);
}

.page-about .tl-index__link::before {
  content: "";
  width: 14px;
  height: 1px;
  background: currentColor;
  opacity: .45;
}

.page-about .tl-index__link:hover,
.page-about .tl-index__link:focus-visible {
  background: var(--green-deep);
  border-color: var(--green-deep);
  color: var(--board);
}

.page-about .tl-node {
  position: relative;
  padding: 16px 0 18px 24px;
  border-top: var(--about-line);
  scroll-margin-top: 96px;
}

.page-about .tl-node:first-child {
  border-top: 0;
}

.page-about .tl-node::before {
  content: "";
  position: absolute;
  left: 3px;
  top: 0;
  bottom: 0;
  width: 1px;
  background: rgba(23, 61, 43, .2);
}

.page-about .tl-node:first-child::before {
  top: 28px;
}

.page-about .tl-node:last-child::before {
  bottom: auto;
  height: 42px;
}

.page-about .tl-node::after {
  content: "";
  position: absolute;
  left: 0;
  top: 28px;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--green-deep);
  box-shadow: 0 0 0 3px var(--moss);
  transition: background var(--dur-2) var(--ease), box-shadow var(--dur-2) var(--ease);
}

.page-about .tl-node.is-visible::after {
  background: var(--amber);
  box-shadow: 0 0 0 3px rgba(217, 119, 46, .22);
}

.page-about .tl-node summary {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px 12px;
  min-height: 44px;
  padding: 4px 0;
  list-style: none;
  cursor: pointer;
}

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

.page-about .tl-node summary:focus-visible {
  outline: 2px solid var(--blue);
  outline-offset: 4px;
}

.page-about .tl-node__season {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--green-mid);
}

.page-about .tl-node__toggle {
  display: inline-grid;
  place-items: center;
  width: 24px;
  height: 24px;
  margin-left: auto;
  border: var(--about-line);
  border-radius: 50%;
  font-family: var(--font-mono);
  font-size: 14px;
  line-height: 1;
  color: var(--green-deep);
  background: rgba(255, 253, 247, .8);
}

.page-about .tl-node__toggle::before {
  content: "+";
}

.page-about .tl-node[open] .tl-node__toggle::before {
  content: "−";
}

.page-about .tl-node__title {
  flex: 1 1 100%;
  margin: 0;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 20px;
  line-height: 1.4;
  color: var(--ink);
}

.page-about .tl-node__body {
  max-width: 62ch;
  padding-top: 8px;
}

.page-about .tl-node__body p {
  margin: 10px 0 0;
  font-size: 14.8px;
  line-height: 1.85;
  color: rgba(16, 25, 20, .72);
}

.page-about .tl-node__meta {
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .06em;
  color: rgba(16, 25, 20, .48) !important;
}

/* ---------- 三条内容线 ---------- */
.page-about .about-lines {
  padding: 48px 0 52px;
  background: var(--board);
}

.page-about .about-lines__head {
  max-width: 640px;
}

.page-about .about-lines__grid {
  display: grid;
  gap: 1px;
  margin-top: 26px;
  border: var(--about-line);
  background: rgba(16, 25, 20, .16);
}

.page-about .line-card {
  padding: 20px 18px 22px;
  background: var(--about-paper);
}

.page-about .line-card__num {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .14em;
  color: var(--amber);
}

.page-about .line-card h3 {
  margin: 8px 0 0;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 21px;
  color: var(--ink);
}

.page-about .line-card p {
  margin: 10px 0 0;
  font-size: 14.5px;
  line-height: 1.78;
  color: var(--about-muted);
}

.page-about .line-card ul {
  display: grid;
  gap: 7px;
  margin: 15px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .line-card li {
  position: relative;
  padding-left: 15px;
  font-size: 13.5px;
  line-height: 1.65;
  color: var(--ink);
}

.page-about .line-card li::before {
  content: "";
  position: absolute;
  left: 0;
  top: .72em;
  width: 7px;
  height: 1px;
  background: var(--green-mid);
}

.page-about .about-lines__figure {
  margin-top: 26px;
}

/* ---------- 团队 ---------- */
.page-about .about-team {
  padding: 48px 0 52px;
  color: var(--board);
  background: var(--green-deep);
}

.page-about .about-team__grid {
  display: grid;
  gap: 26px;
}

.page-about .about-team .eyebrow {
  color: var(--amber-soft);
}

.page-about .about-team h2 {
  color: var(--board);
}

.page-about .about-team .about-copy {
  color: rgba(245, 242, 233, .78);
}

.page-about .about-team__figure {
  border: var(--about-line-light);
  background: rgba(245, 242, 233, .06);
  box-shadow: none;
}

.page-about .about-team__figure figcaption {
  border-top: var(--about-line-light);
  color: rgba(245, 242, 233, .6);
  background: transparent;
}

.page-about .about-team__duty {
  display: grid;
  gap: 0;
  margin: 24px 0 0;
  border-top: var(--about-line-light);
}

.page-about .about-team__duty > div {
  display: grid;
  grid-template-columns: 88px minmax(0, 1fr);
  gap: 14px;
  padding: 12px 0;
  border-bottom: var(--about-line-light);
}

.page-about .about-team__duty dt {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .1em;
  color: rgba(245, 242, 233, .55);
}

.page-about .about-team__duty dd {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.7;
  color: rgba(245, 242, 233, .9);
}

/* ---------- 协作 ---------- */
.page-about .about-partners {
  padding: 48px 0 52px;
  background: var(--board);
}

.page-about .about-partners__grid {
  display: grid;
  gap: 26px;
}

.page-about .about-partners__list {
  display: grid;
  margin: 0;
  padding: 0;
  list-style: none;
  border-top: var(--about-line);
}

.page-about .about-partners__list li {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding: 14px 0;
  border-bottom: var(--about-line);
  font-size: 14px;
  line-height: 1.65;
  color: var(--ink);
}

.page-about .about-partners__list .num {
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--amber);
}

/* ---------- 收束 ---------- */
.page-about .about-next {
  padding: 0 0 56px;
  background: var(--board);
}

.page-about .about-next__inner {
  display: grid;
  gap: 20px;
  padding: 26px 20px 28px;
  border: var(--about-line);
  border-left: 4px solid var(--amber);
  background: var(--about-paper);
}

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

/* ---------- 断点 ---------- */
@media (min-width: 768px) {
  .page-about .about-hero {
    padding: 34px 0 64px;
  }

  .page-about .about-hero h1 {
    font-size: clamp(40px, 5.2vw, 58px);
    max-width: 22ch;
  }

  .page-about .about-hero__intro {
    font-size: 17px;
  }

  .page-about .about-origin,
  .page-about .about-timeline,
  .page-about .about-lines,
  .page-about .about-team,
  .page-about .about-partners {
    padding-top: 60px;
    padding-bottom: 64px;
  }

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

  .page-about .about-next__inner {
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: center;
    gap: 32px;
    padding: 32px 28px;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1fr) 300px;
    align-items: end;
    gap: 46px;
  }

  .page-about .about-origin__grid {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.05fr);
    align-items: start;
    gap: 52px;
  }

  .page-about .tl-layout {
    grid-template-columns: 206px minmax(0, 1fr);
    align-items: start;
    gap: 46px;
  }

  .page-about .tl-index {
    position: sticky;
    top: 92px;
  }

  .page-about .tl-index__list {
    flex-direction: column;
    flex-wrap: nowrap;
    gap: 6px;
  }

  .page-about .tl-index__link {
    width: 100%;
    justify-content: flex-start;
  }

  .page-about .tl-node {
    padding: 18px 0 22px 30px;
  }

  .page-about .tl-node__title {
    font-size: 22px;
  }

  .page-about .about-team__grid {
    grid-template-columns: minmax(0, .92fr) minmax(0, 1.08fr);
    align-items: center;
    gap: 52px;
  }

  .page-about .about-partners__grid {
    grid-template-columns: minmax(0, 1fr) 320px;
    align-items: start;
    gap: 52px;
  }
}

@media (min-width: 1200px) {
  .page-about .about-hero__board {
    padding: 22px 22px 24px;
  }

  .page-about .line-card {
    padding: 24px 22px 26px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .tl-node::after,
  .page-about .tl-index__link,
  .page-about .about-hero .breadcrumb__link {
    transition: none;
  }
}