.page-about {
  --about-pad: clamp(48px, 8vw, 100px);
  background: var(--tb-ink);
  color: var(--tb-bone);
  font-family: var(--tb-body);
  overflow-x: hidden;
}

.page-about .about-wrap {
  max-width: var(--tb-max);
  margin: 0 auto;
  padding: 0 var(--tb-gutter);
}

.page-about .about-section {
  padding: var(--about-pad) 0;
}

.page-about .about-head {
  display: grid;
  gap: 8px;
  margin-bottom: clamp(24px, 4vw, 44px);
  max-width: 62ch;
}

.page-about .about-head__num {
  font-family: var(--tb-mono);
  font-size: 13px;
  letter-spacing: .2em;
  color: var(--tb-cyan);
  margin: 0;
}

.page-about .about-head__kicker {
  font-family: var(--tb-mono);
  font-size: 12px;
  letter-spacing: .24em;
  color: var(--tb-stone);
  margin: 0;
}

.page-about .about-head h2 {
  font-family: var(--tb-display);
  font-size: clamp(26px, 4.4vw, 46px);
  font-weight: 900;
  line-height: 1.12;
  letter-spacing: -.01em;
  margin: 4px 0 0;
}

.page-about .about-lede {
  font-size: clamp(15px, 2vw, 17px);
  line-height: 1.78;
  color: rgba(242, 235, 221, .78);
  margin: 8px 0 0;
}

/* ---------- 首屏框景 ---------- */
.page-about .about-hero {
  position: relative;
  padding: calc(var(--tb-hh) + 44px) var(--tb-gutter) 40px;
  background:
    radial-gradient(120% 90% at 84% -10%, rgba(76, 242, 212, .12), transparent 62%),
    radial-gradient(90% 70% at 0% 100%, rgba(165, 106, 78, .16), transparent 60%),
    linear-gradient(170deg, #071A17 0%, #0C2233 100%);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: var(--tb-hh);
  height: 10px;
  background: repeating-linear-gradient(90deg, rgba(76, 242, 212, .5) 0 1px, transparent 1px 22px);
  pointer-events: none;
}

.page-about .about-hero__grid {
  position: relative;
  max-width: var(--tb-max);
  margin: 0 auto;
  padding: clamp(20px, 4vw, 46px);
  display: grid;
  gap: clamp(24px, 4vw, 40px);
  border: 1px solid var(--tb-line);
  background: rgba(7, 26, 23, .45);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 40px), calc(100% - 40px) 100%, 0 100%);
}

.page-about .about-hero__grid::after {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 96px;
  height: 3px;
  background: var(--tb-whistle);
}

.page-about .about-crumbs {
  display: flex;
  align-items: center;
  gap: 8px;
  font-family: var(--tb-mono);
  font-size: 12px;
  letter-spacing: .06em;
  color: var(--tb-stone);
  margin-bottom: 22px;
  flex-wrap: wrap;
}

.page-about .about-crumbs a {
  color: var(--tb-stone);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color .18s var(--tb-ease), border-color .18s var(--tb-ease);
}

.page-about .about-crumbs a:hover,
.page-about .about-crumbs a:focus-visible {
  color: var(--tb-whistle);
  border-bottom-color: var(--tb-whistle);
}

.page-about .about-crumbs [aria-current="page"] {
  color: var(--tb-bone);
}

.page-about .about-crumbs__sep {
  color: var(--tb-clay);
}

.page-about .about-hero__kicker {
  display: flex;
  align-items: center;
  gap: 8px;
  font-family: var(--tb-mono);
  font-size: 12px;
  letter-spacing: .18em;
  color: var(--tb-cyan);
  margin: 0 0 14px;
}

.page-about .about-pulse {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--tb-cyan);
  box-shadow: 0 0 0 4px rgba(76, 242, 212, .16);
}

.page-about .about-hero h1 {
  font-family: var(--tb-display);
  font-size: clamp(34px, 7.2vw, 68px);
  font-weight: 900;
  line-height: 1.02;
  letter-spacing: -.015em;
  margin: 0 0 18px;
  color: var(--tb-bone);
}

.page-about .about-hero__lede {
  font-size: clamp(15px, 2.1vw, 18px);
  line-height: 1.8;
  color: rgba(242, 235, 221, .82);
  margin: 0 0 28px;
  max-width: 52ch;
}

.page-about .about-hero__jump {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(142px, 1fr));
  gap: 1px;
  background: var(--tb-line-soft);
  border-top: 1px solid var(--tb-line);
  border-bottom: 1px solid var(--tb-line);
}

.page-about .about-hero__jump li {
  background: rgba(7, 26, 23, .6);
}

.page-about .about-hero__jump a {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 14px 12px;
  font-size: 13px;
  color: var(--tb-bone);
  text-decoration: none;
  transition: background .18s var(--tb-ease), color .18s var(--tb-ease);
}

.page-about .about-hero__jump a:hover,
.page-about .about-hero__jump a:focus-visible {
  background: rgba(255, 210, 63, .12);
  color: var(--tb-whistle);
}

.page-about .about-hero__jidx {
  font-family: var(--tb-mono);
  font-size: 11px;
  color: var(--tb-clay);
}

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

.page-about .about-hero__figure img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
  border: 1px solid var(--tb-line);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 30px), calc(100% - 30px) 100%, 0 100%);
  filter: saturate(.9) contrast(1.05);
}

.page-about .about-hero__figure figcaption {
  margin-top: 10px;
  font-family: var(--tb-mono);
  font-size: 11px;
  letter-spacing: .08em;
  color: var(--tb-stone);
}

.page-about .about-hero__stats {
  list-style: none;
  max-width: var(--tb-max);
  margin: 28px auto 0;
  padding: 20px 0 0;
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 18px 12px;
  border-top: 1px solid var(--tb-line);
}

.page-about .about-hero__num {
  display: block;
  font-family: var(--tb-mono);
  font-size: clamp(22px, 3.4vw, 32px);
  font-weight: 700;
  color: var(--tb-whistle);
  line-height: 1.1;
}

.page-about .about-hero__lbl {
  display: block;
  margin-top: 4px;
  font-size: 12px;
  color: var(--tb-stone);
  letter-spacing: .04em;
}

/* ---------- 使命 ---------- */
.page-about .about-section--mission {
  background: var(--tb-ink-2);
  border-top: 1px solid var(--tb-line);
  border-bottom: 1px solid var(--tb-line);
}

.page-about .about-mission {
  display: grid;
  gap: clamp(22px, 4vw, 48px);
}

.page-about .about-mission__quote {
  border-left: 3px solid var(--tb-clay);
  padding-left: clamp(16px, 3vw, 26px);
}

.page-about .about-mission__quote p {
  font-family: var(--tb-serif);
  font-size: clamp(22px, 3.6vw, 36px);
  line-height: 1.42;
  margin: 0;
  color: var(--tb-bone);
}

.page-about .about-mission__body {
  display: grid;
  gap: 16px;
  align-content: start;
}

.page-about .about-mission__body p {
  margin: 0;
  font-size: clamp(15px, 1.9vw, 16.5px);
  line-height: 1.82;
  color: rgba(242, 235, 221, .8);
}

/* ---------- 团队 ---------- */
.page-about .about-section--team {
  background:
    radial-gradient(80% 60% at 100% 0%, rgba(62, 92, 75, .35), transparent 64%),
    var(--tb-ink);
}

.page-about .about-team {
  display: grid;
  gap: 16px;
}

.page-about .about-team__panel {
  position: relative;
  padding: 24px 20px 26px;
  background: var(--tb-moss);
  color: var(--tb-bone);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 22px), calc(100% - 22px) 100%, 0 100%);
}

.page-about .about-team__panel::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 46px;
  height: 3px;
  background: var(--tb-whistle);
}

.page-about .about-team__panel--narrow {
  background: rgba(62, 92, 75, .72);
}

.page-about .about-team__count {
  font-family: var(--tb-mono);
  font-size: 34px;
  font-weight: 700;
  line-height: 1;
  color: var(--tb-whistle);
  margin: 0 0 12px;
}

.page-about .about-team__count span {
  font-size: 13px;
  color: var(--tb-stone-light);
  margin-left: 4px;
  font-weight: 400;
}

.page-about .about-team__panel h3 {
  font-family: var(--tb-display);
  font-size: 20px;
  font-weight: 800;
  letter-spacing: .02em;
  margin: 0 0 8px;
  color: var(--tb-bone);
}

.page-about .about-team__panel p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.75;
  color: rgba(242, 235, 221, .84);
}

.page-about .about-team__tags {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin: 14px 0 0;
  padding: 0;
}

.page-about .about-team__tags li {
  font-family: var(--tb-mono);
  font-size: 11px;
  letter-spacing: .06em;
  padding: 3px 8px;
  color: var(--tb-ink);
  background: var(--tb-stone-light);
}

.page-about .about-team__panel--narrow .about-team__tags li {
  background: rgba(242, 235, 221, .22);
  color: var(--tb-bone);
}

.page-about .about-team__figure {
  margin: 0;
}

.page-about .about-team__figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  border: 1px solid var(--tb-line);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 26px), calc(100% - 26px) 100%, 0 100%);
}

.page-about .about-team__figure figcaption {
  margin-top: 10px;
  font-family: var(--tb-mono);
  font-size: 11px;
  letter-spacing: .08em;
  color: var(--tb-stone);
}

/* ---------- 流程 ---------- */
.page-about .about-section--process {
  background: var(--tb-ink-2);
  border-top: 1px solid var(--tb-line);
  border-bottom: 1px solid var(--tb-line);
}

.page-about .about-flow {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--tb-line-soft);
  border-top: 1px solid var(--tb-line);
  border-bottom: 1px solid var(--tb-line);
}

.page-about .about-flow__item {
  background: var(--tb-ink-2);
  padding: 22px 18px 24px;
  position: relative;
  transition: background .2s var(--tb-ease);
}

.page-about .about-flow__item:hover {
  background: #10293c;
}

.page-about .about-flow__idx {
  font-family: var(--tb-mono);
  font-size: 12px;
  letter-spacing: .16em;
  color: var(--tb-signal);
}

.page-about .about-flow__item h3 {
  font-family: var(--tb-display);
  font-size: 19px;
  font-weight: 800;
  margin: 8px 0 6px;
  color: var(--tb-bone);
}

.page-about .about-flow__item p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.76;
  color: rgba(242, 235, 221, .76);
}

/* ---------- 时间线 ---------- */
.page-about .about-section--timeline {
  background:
    radial-gradient(70% 60% at 0% 10%, rgba(165, 106, 78, .18), transparent 62%),
    var(--tb-ink);
}

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

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

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

.page-about .about-timeline__item {
  position: relative;
  border-left: 1px solid var(--tb-line);
  padding-left: 14px;
}

.page-about .about-timeline__item::before {
  content: "";
  position: absolute;
  left: -5px;
  top: 22px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--tb-clay);
  box-shadow: 0 0 0 4px rgba(165, 106, 78, .18);
}

.page-about .about-timeline__item details {
  background: rgba(62, 92, 75, .28);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 18px), calc(100% - 18px) 100%, 0 100%);
}

.page-about .about-timeline__item summary {
  list-style: none;
  cursor: pointer;
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 6px 12px;
  padding: 18px 18px 16px;
}

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

.page-about .about-timeline__item summary::after {
  content: "+";
  margin-left: auto;
  font-family: var(--tb-mono);
  font-size: 16px;
  color: var(--tb-whistle);
}

.page-about .about-timeline__item details[open] summary::after {
  content: "–";
}

.page-about .about-timeline__item summary:focus-visible {
  outline: 2px solid var(--tb-cyan);
  outline-offset: -2px;
}

.page-about .about-timeline__ver {
  font-family: var(--tb-mono);
  font-size: 12px;
  font-weight: 700;
  color: var(--tb-ink);
  background: var(--tb-whistle);
  padding: 2px 7px;
}

.page-about .about-timeline__name {
  font-family: var(--tb-display);
  font-size: 19px;
  font-weight: 800;
  color: var(--tb-bone);
}

.page-about .about-timeline__hint {
  flex-basis: 100%;
  font-size: 12.5px;
  color: var(--tb-stone);
  letter-spacing: .02em;
}

.page-about .about-timeline__item details p {
  margin: 0;
  padding: 0 18px 20px;
  font-size: 14.5px;
  line-height: 1.8;
  color: rgba(242, 235, 221, .8);
}

/* ---------- 覆盖 ---------- */
.page-about .about-section--coverage {
  background: var(--tb-bone);
  color: var(--tb-ink);
}

.page-about .about-section--coverage .about-head h2 {
  color: var(--tb-ink);
}

.page-about .about-section--coverage .about-head__num {
  color: var(--tb-clay);
}

.page-about .about-section--coverage .about-head__kicker {
  color: rgba(7, 26, 23, .55);
}

.page-about .about-section--coverage .about-lede {
  color: rgba(7, 26, 23, .72);
}

.page-about .about-stats {
  display: grid;
  gap: 1px;
  background: rgba(7, 26, 23, .16);
  border: 1px solid rgba(7, 26, 23, .16);
  margin: 0 0 clamp(26px, 4vw, 42px);
}

.page-about .about-stats__cell {
  background: var(--tb-bone);
  padding: 20px 18px 22px;
}

.page-about .about-stats dt {
  font-family: var(--tb-mono);
  font-size: 12px;
  letter-spacing: .14em;
  color: var(--tb-moss);
}

.page-about .about-stats dd {
  margin: 8px 0 6px;
  font-size: 14px;
  color: rgba(7, 26, 23, .6);
}

.page-about .about-stats__num {
  font-family: var(--tb-mono);
  font-size: clamp(28px, 4.4vw, 40px);
  font-weight: 700;
  color: var(--tb-ink);
  line-height: 1;
  margin-right: 4px;
}

.page-about .about-stats__cell p {
  margin: 0;
  font-size: 13.5px;
  line-height: 1.7;
  color: rgba(7, 26, 23, .68);
}

.page-about .about-devices {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0;
  border-top: 1px solid rgba(7, 26, 23, .2);
}

.page-about .about-devices li {
  display: grid;
  gap: 6px;
  padding: 18px 0;
  border-bottom: 1px solid rgba(7, 26, 23, .14);
  position: relative;
  padding-left: 16px;
}

.page-about .about-devices li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 26px;
  width: 8px;
  height: 1px;
  background: var(--tb-clay);
}

.page-about .about-devices h3 {
  font-family: var(--tb-display);
  font-size: 18px;
  font-weight: 800;
  margin: 0;
  color: var(--tb-ink);
}

.page-about .about-devices p {
  margin: 0;
  font-size: 14px;
  line-height: 1.75;
  color: rgba(7, 26, 23, .7);
}

/* ---------- 合作 ---------- */
.page-about .about-section--partners {
  background:
    radial-gradient(90% 70% at 90% 0%, rgba(76, 242, 212, .09), transparent 60%),
    var(--tb-ink-2);
}

.page-about .about-partners {
  display: grid;
  gap: 14px;
  margin-bottom: clamp(26px, 4vw, 44px);
}

.page-about .about-partners__item {
  padding: 22px 20px 24px;
  background: rgba(12, 34, 51, .82);
  border-left: 3px solid var(--tb-moss);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 20px), calc(100% - 20px) 100%, 0 100%);
}

.page-about .about-partners__item--b {
  border-left-color: var(--tb-cyan);
}

.page-about .about-partners__item--c {
  border-left-color: var(--tb-signal);
}

.page-about .about-partners__item h3 {
  font-family: var(--tb-display);
  font-size: 19px;
  font-weight: 800;
  margin: 0 0 8px;
  color: var(--tb-bone);
}

.page-about .about-partners__item p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.78;
  color: rgba(242, 235, 221, .78);
}

.page-about .about-standards {
  border-top: 1px solid var(--tb-line);
  padding-top: clamp(20px, 3vw, 32px);
}

.page-about .about-standards h3 {
  font-family: var(--tb-serif);
  font-size: clamp(19px, 2.6vw, 24px);
  font-weight: 700;
  margin: 0 0 16px;
  color: var(--tb-bone);
}

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

.page-about .about-standards li {
  position: relative;
  padding-left: 22px;
  font-size: 14.5px;
  line-height: 1.78;
  color: rgba(242, 235, 221, .78);
}

.page-about .about-standards li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 9px;
  width: 10px;
  height: 2px;
  background: var(--tb-whistle);
}

.page-about .about-standards strong {
  color: var(--tb-bone);
  font-weight: 700;
}

/* ---------- 收尾 ---------- */
.page-about .about-cta {
  background: linear-gradient(180deg, #071A17 0%, #0C2233 100%);
  border-top: 1px solid var(--tb-line);
  padding: clamp(44px, 7vw, 84px) 0;
}

.page-about .about-cta h2 {
  font-family: var(--tb-display);
  font-size: clamp(24px, 4vw, 40px);
  font-weight: 900;
  line-height: 1.15;
  margin: 0 0 clamp(20px, 3vw, 32px);
  color: var(--tb-bone);
}

.page-about .about-cta__grid {
  display: grid;
  gap: 12px;
}

.page-about .about-cta__link {
  display: grid;
  gap: 6px;
  padding: 18px 18px 20px;
  text-decoration: none;
  background: rgba(62, 92, 75, .24);
  border-left: 3px solid var(--tb-whistle);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 16px), calc(100% - 16px) 100%, 0 100%);
  transition: background .18s var(--tb-ease), border-color .18s var(--tb-ease), transform .18s var(--tb-ease);
}

.page-about .about-cta__link:hover,
.page-about .about-cta__link:focus-visible {
  background: rgba(255, 122, 47, .16);
  border-left-color: var(--tb-signal);
  transform: translateY(-2px);
}

.page-about .about-cta__title {
  font-family: var(--tb-display);
  font-size: 18px;
  font-weight: 800;
  color: var(--tb-bone);
}

.page-about .about-cta__desc {
  font-size: 13.5px;
  line-height: 1.7;
  color: var(--tb-stone);
}

/* ---------- 响应式 ---------- */
@media (min-width: 640px) {
  .page-about .about-hero__stats {
    grid-template-columns: repeat(4, 1fr);
    gap: 12px;
  }

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

  .page-about .about-team__figure {
    grid-column: span 2;
  }

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

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

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

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: 1.12fr .88fr;
    align-items: center;
  }

  .page-about .about-mission {
    grid-template-columns: .92fr 1.08fr;
    align-items: start;
  }

  .page-about .about-team {
    grid-template-columns: repeat(6, 1fr);
    gap: 18px;
  }

  .page-about .about-team__panel--wide {
    grid-column: span 4;
  }

  .page-about .about-team__panel--narrow {
    grid-column: span 2;
  }

  .page-about .about-team__panel:nth-of-type(3) {
    grid-column: span 2;
  }

  .page-about .about-team__panel:nth-of-type(4) {
    grid-column: span 4;
  }

  .page-about .about-team__figure {
    grid-column: span 6;
  }

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

  .page-about .about-timeline {
    grid-template-columns: 208px 1fr;
    gap: 40px;
    align-items: start;
  }

  .page-about .about-timeline__rail {
    display: block;
    position: sticky;
    top: calc(var(--tb-hh) + 32px);
    padding-right: 18px;
    border-right: 1px solid var(--tb-line);
  }

  .page-about .about-timeline__railtitle {
    display: block;
    font-family: var(--tb-mono);
    font-size: 11px;
    letter-spacing: .2em;
    color: var(--tb-stone);
    margin-bottom: 14px;
  }

  .page-about .about-timeline__rail ul {
    list-style: none;
    margin: 0;
    padding: 0;
    display: grid;
    gap: 14px;
  }

  .page-about .about-timeline__rail a {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 13px;
    color: rgba(242, 235, 221, .7);
    text-decoration: none;
    transition: color .18s var(--tb-ease);
  }

  .page-about .about-timeline__rail a:hover,
  .page-about .about-timeline__rail a:focus-visible {
    color: var(--tb-whistle);
  }

  .page-about .about-timeline__dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--tb-moss);
    flex: none;
    transition: background .18s var(--tb-ease);
  }

  .page-about .about-timeline__rail a:hover .about-timeline__dot,
  .page-about .about-timeline__rail a:focus-visible .about-timeline__dot {
    background: var(--tb-whistle);
  }

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

  .page-about .about-devices {
    grid-template-columns: repeat(2, 1fr);
    column-gap: 40px;
  }

  .page-about .about-partners {
    grid-template-columns: 1.15fr .85fr;
    grid-template-areas:
      "a b"
      "a c";
    gap: 16px;
  }

  .page-about .about-partners__item--a {
    grid-area: a;
  }

  .page-about .about-partners__item--b {
    grid-area: b;
  }

  .page-about .about-partners__item--c {
    grid-area: c;
  }

  .page-about .about-standards ul {
    grid-template-columns: repeat(2, 1fr);
    gap: 14px 36px;
  }
}

@media (min-width: 1180px) {
  .page-about .about-flow {
    grid-template-columns: repeat(6, 1fr);
  }

  .page-about .about-flow__item {
    padding: 26px 16px 28px;
  }

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

@media (prefers-reduced-motion: reduce) {
  .page-about .about-cta__link,
  .page-about .about-flow__item,
  .page-about .about-hero__jump a {
    transition: none;
  }

  .page-about .about-cta__link:hover,
  .page-about .about-cta__link:focus-visible {
    transform: none;
  }
}