.page-about {
  --about-pad: clamp(44px, 7vw, 88px);
  color: var(--white);
}

/* ---------- 面包屑 ---------- */
.page-about .breadcrumbs {
  padding-block: 16px 4px;
}
.page-about .breadcrumbs__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: 0.08em;
  color: var(--muted);
}
.page-about .breadcrumbs__item:not(:last-child)::after {
  content: "/";
  margin-left: 8px;
  color: var(--line);
}
.page-about .breadcrumbs__link {
  color: var(--muted);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color 160ms var(--ease), border-color 160ms var(--ease);
}
.page-about .breadcrumbs__link:hover,
.page-about .breadcrumbs__link:focus-visible {
  color: var(--cyan);
  border-bottom-color: var(--cyan);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding: clamp(36px, 7vw, 84px) 0 clamp(40px, 6vw, 80px);
  background:
    radial-gradient(110% 80% at 88% -10%, rgba(0, 229, 200, 0.16), transparent 62%),
    linear-gradient(180deg, var(--ink-800) 0%, var(--ink-900) 100%);
}
.page-about .about-hero::before {
  content: "";
  position: absolute;
  top: -18%;
  right: -14%;
  width: min(780px, 80%);
  height: 150%;
  background: linear-gradient(155deg, rgba(0, 229, 200, 0.18), rgba(18, 58, 87, 0.42) 46%, rgba(4, 18, 31, 0) 80%);
  clip-path: polygon(32% 0, 100% 0, 100% 100%, 0 70%);
  pointer-events: none;
}
.page-about .about-hero::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(147, 175, 192, 0.07) 1px, transparent 1px),
    linear-gradient(90deg, rgba(147, 175, 192, 0.07) 1px, transparent 1px);
  background-size: 56px 56px;
  -webkit-mask-image: linear-gradient(180deg, rgba(0, 0, 0, 0.85), transparent 88%);
  mask-image: linear-gradient(180deg, rgba(0, 0, 0, 0.85), transparent 88%);
  pointer-events: none;
}
.page-about .about-hero__inner {
  position: relative;
  z-index: 2;
  display: grid;
  gap: clamp(28px, 5vw, 48px);
}
.page-about .about-hero__title {
  margin: 14px 0 18px;
  font-family: var(--font-display);
  font-size: clamp(34px, 8.4vw, 68px);
  font-weight: 700;
  line-height: 1.06;
  letter-spacing: -0.02em;
  text-transform: none;
  color: var(--white);
}
.page-about .about-hero__lead {
  max-width: 46ch;
  font-size: 16px;
  line-height: 1.75;
  color: #c3d7e2;
}
.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 26px;
}
.page-about .about-hero__board {
  position: relative;
  padding: 22px 18px 18px;
  background: linear-gradient(180deg, var(--panel) 0%, var(--panel-deep) 100%);
  border: 1px solid var(--line);
  border-top: 2px solid var(--cyan);
  box-shadow: var(--shadow-card);
}
.page-about .about-hero__board::after {
  content: "";
  position: absolute;
  right: -8px;
  bottom: -8px;
  width: 46%;
  height: 30%;
  border-right: 1px solid rgba(0, 229, 200, 0.35);
  border-bottom: 1px solid rgba(0, 229, 200, 0.35);
  pointer-events: none;
}
.page-about .board__title {
  margin: 0 0 14px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.24em;
  text-transform: uppercase;
  color: var(--muted);
}
.page-about .board__row {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 14px;
  padding: 11px 0;
  border-bottom: 1px dashed rgba(18, 58, 87, 0.95);
}
.page-about .board__row:last-child {
  border-bottom: 0;
  padding-bottom: 0;
}
.page-about .board__num {
  font-family: var(--font-mono);
  font-size: clamp(22px, 5vw, 28px);
  font-weight: 500;
  font-variant-numeric: tabular-nums;
  color: var(--cyan);
}
.page-about .board__label {
  flex: 1;
  font-size: 12.5px;
  line-height: 1.5;
  text-align: right;
  color: var(--muted);
}

/* ---------- 章节骨架 ---------- */
.page-about .chapter {
  position: relative;
  border-top: 1px solid var(--line);
}
.page-about .chapter::after {
  content: "";
  position: absolute;
  top: -1px;
  left: 0;
  width: 72px;
  height: 2px;
  background: var(--cyan);
}
.page-about .chapter__head {
  margin-bottom: clamp(22px, 4vw, 36px);
}
.page-about .chapter__title {
  margin: 12px 0 0;
  font-family: var(--font-display);
  font-size: clamp(25px, 5.4vw, 42px);
  font-weight: 700;
  line-height: 1.14;
  letter-spacing: -0.015em;
  color: var(--white);
}
.page-about .chapter__body > p {
  margin: 0 0 16px;
  font-size: 16px;
  line-height: 1.78;
  color: #c3d7e2;
}
.page-about .chapter__body > p:last-child {
  margin-bottom: 0;
}
.page-about .chapter__body .lead {
  font-size: clamp(16px, 2.2vw, 18px);
  line-height: 1.72;
  color: var(--white);
}

/* ---------- 图片 ---------- */
.page-about .about-figure {
  margin: clamp(26px, 4vw, 40px) 0 0;
}
.page-about .media__frame {
  position: relative;
  overflow: hidden;
  border: 1px solid var(--line);
  background:
    linear-gradient(120deg, rgba(0, 229, 200, 0.08), rgba(4, 18, 31, 0)),
    repeating-linear-gradient(90deg, rgba(147, 175, 192, 0.06) 0 1px, transparent 1px 46px),
    var(--panel-deep);
}
.page-about .media__img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
}
.page-about .media__caption {
  margin-top: 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--muted);
}

/* ---------- 四道工序 ---------- */
.page-about .steps {
  display: grid;
  gap: 14px;
  margin-top: 26px;
}
.page-about .step {
  position: relative;
  background: linear-gradient(180deg, rgba(237, 243, 246, 0.05) 0%, rgba(10, 33, 54, 0.9) 100%);
  border: 1px solid var(--line);
  border-left: 2px solid var(--cyan);
  box-shadow: 5px 5px 0 -1px rgba(18, 58, 87, 0.55);
  transition: transform 180ms var(--ease), box-shadow 180ms var(--ease), border-color 180ms var(--ease);
}
.page-about .step:hover {
  transform: translateY(-4px);
  border-left-color: var(--cyan-bright);
  box-shadow: 5px 5px 0 -1px rgba(0, 229, 200, 0.35), var(--glow-cyan);
}
.page-about .step__q {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 16px 16px;
  cursor: pointer;
  list-style: none;
  font-size: 16px;
  font-weight: 600;
  color: var(--white);
}
.page-about .step__q::-webkit-details-marker {
  display: none;
}
.page-about .step__num {
  flex: none;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.1em;
  color: var(--coral);
  font-variant-numeric: tabular-nums;
}
.page-about .step__name {
  flex: 1;
  min-width: 0;
}
.page-about .step__icon {
  position: relative;
  flex: none;
  width: 14px;
  height: 14px;
}
.page-about .step__icon::before,
.page-about .step__icon::after {
  content: "";
  position: absolute;
  background: var(--cyan);
  transition: transform 200ms var(--ease), opacity 200ms var(--ease);
}
.page-about .step__icon::before {
  top: 6px;
  left: 0;
  width: 14px;
  height: 2px;
}
.page-about .step__icon::after {
  top: 0;
  left: 6px;
  width: 2px;
  height: 14px;
}
.page-about .step[open] .step__icon::after {
  transform: scaleY(0);
  opacity: 0;
}
.page-about .step__a {
  padding: 0 16px 18px 44px;
}
.page-about .step__a p {
  margin: 0 0 10px;
  font-size: 15px;
  line-height: 1.75;
  color: #c3d7e2;
}
.page-about .step__a p:last-child {
  margin-bottom: 0;
}
.page-about .step__detail {
  padding-left: 12px;
  border-left: 2px solid rgba(255, 194, 75, 0.55);
  font-family: var(--font-mono);
  font-size: 12.5px !important;
  color: var(--muted) !important;
}

/* ---------- 团队切换 ---------- */
.page-about .team-tabs {
  position: relative;
  margin-top: 26px;
}
.page-about .team-tabs__radio {
  position: absolute;
  width: 1px;
  height: 1px;
  opacity: 0;
  pointer-events: none;
}
.page-about .team-tabs__labels {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 18px;
}
.page-about .team-tabs__label {
  cursor: pointer;
  padding: 9px 14px;
  border: 1px solid var(--line);
  background: var(--panel-deep);
  color: var(--muted);
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: 0.06em;
  transition: color 160ms var(--ease), border-color 160ms var(--ease), background 160ms var(--ease);
}
.page-about .team-tabs__label:hover {
  color: var(--cyan-bright);
  border-color: rgba(0, 229, 200, 0.5);
}
.page-about #team-tab-1:checked ~ .team-tabs__labels label[for="team-tab-1"],
.page-about #team-tab-2:checked ~ .team-tabs__labels label[for="team-tab-2"],
.page-about #team-tab-3:checked ~ .team-tabs__labels label[for="team-tab-3"] {
  color: var(--ink-900);
  background: var(--cyan);
  border-color: var(--cyan);
  font-weight: 600;
}
.page-about #team-tab-1:focus-visible ~ .team-tabs__labels label[for="team-tab-1"],
.page-about #team-tab-2:focus-visible ~ .team-tabs__labels label[for="team-tab-2"],
.page-about #team-tab-3:focus-visible ~ .team-tabs__labels label[for="team-tab-3"] {
  outline: 2px solid var(--cyan-bright);
  outline-offset: 3px;
}
.page-about .team-tabs__panel,
.page-about .team-panel {
  display: none;
}
.page-about #team-tab-1:checked ~ .team-tabs__panels .team-panel[data-panel="1"],
.page-about #team-tab-2:checked ~ .team-tabs__panels .team-panel[data-panel="2"],
.page-about #team-tab-3:checked ~ .team-tabs__panels .team-panel[data-panel="3"] {
  display: block;
}
.page-about .team-panel {
  position: relative;
  padding: 22px 18px;
  background: linear-gradient(180deg, rgba(10, 33, 54, 0.95) 0%, rgba(7, 26, 43, 0.95) 100%);
  border: 1px solid var(--line);
  border-top: 2px solid var(--coral);
  box-shadow: var(--shadow-card);
}
.page-about .team-panel__title {
  display: flex;
  align-items: baseline;
  gap: 10px;
  margin: 0 0 10px;
  font-family: var(--font-display);
  font-size: clamp(19px, 3.4vw, 24px);
  font-weight: 700;
  letter-spacing: -0.01em;
  color: var(--white);
}
.page-about .team-panel__count {
  font-family: var(--font-mono);
  font-size: clamp(24px, 5vw, 32px);
  font-weight: 500;
  color: var(--coral);
  font-variant-numeric: tabular-nums;
}
.page-about .team-panel__desc {
  margin: 0 0 16px;
  font-size: 15px;
  line-height: 1.72;
  color: #c3d7e2;
}
.page-about .team-panel__list {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 10px;
}
.page-about .team-panel__list li {
  position: relative;
  padding-left: 18px;
  font-size: 14.5px;
  line-height: 1.7;
  color: var(--muted);
}
.page-about .team-panel__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 9px;
  width: 7px;
  height: 7px;
  background: rgba(0, 229, 200, 0.85);
  transform: rotate(45deg);
}

/* ---------- 版本时间轴 ---------- */
.page-about .about-timeline {
  position: relative;
  margin: 26px 0 0;
  padding: 0 0 0 26px;
  list-style: none;
  display: grid;
  gap: 14px;
}
.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 7px;
  top: 10px;
  bottom: 10px;
  width: 1px;
  background: linear-gradient(180deg, var(--cyan) 0%, rgba(0, 229, 200, 0.25) 55%, rgba(18, 58, 87, 0.2) 100%);
}
.page-about .about-timeline > .timeline__item {
  position: relative;
}
.page-about .about-timeline > .timeline__item::before {
  content: "";
  position: absolute;
  left: -23px;
  top: 20px;
  width: 9px;
  height: 9px;
  background: var(--ink-900);
  border: 1px solid var(--cyan);
  transform: rotate(45deg);
  transition: background 180ms var(--ease), box-shadow 180ms var(--ease);
}
.page-about .about-timeline > .timeline__item:hover::before,
.page-about .about-timeline > .timeline__item:focus-within::before {
  background: var(--cyan);
  box-shadow: 0 0 12px rgba(0, 229, 200, 0.85);
}
.page-about .tl-node {
  border: 1px solid var(--line);
  background: linear-gradient(180deg, rgba(10, 33, 54, 0.92) 0%, rgba(7, 26, 43, 0.92) 100%);
  transition: transform 180ms var(--ease), border-color 180ms var(--ease);
}
.page-about .tl-node:hover {
  transform: translateY(-4px);
  border-color: rgba(0, 229, 200, 0.45);
}
.page-about .tl-node[open] {
  border-color: rgba(0, 229, 200, 0.55);
}
.page-about .tl-node__sum {
  display: grid;
  grid-template-columns: auto 1fr auto;
  grid-template-areas:
    "idx title icon"
    "idx stage icon";
  align-items: center;
  column-gap: 12px;
  row-gap: 4px;
  padding: 14px 16px;
  cursor: pointer;
  list-style: none;
}
.page-about .tl-node__sum::-webkit-details-marker {
  display: none;
}
.page-about .tl-node__idx {
  grid-area: idx;
  font-family: var(--font-mono);
  font-size: 20px;
  font-weight: 500;
  color: var(--amber);
  font-variant-numeric: tabular-nums;
}
.page-about .tl-node__title {
  grid-area: title;
  margin: 0;
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 700;
  letter-spacing: -0.01em;
  color: var(--white);
}
.page-about .tl-node__stage {
  grid-area: stage;
  font-size: 12.5px;
  line-height: 1.5;
  color: var(--muted);
}
.page-about .tl-node__icon {
  grid-area: icon;
  position: relative;
  width: 13px;
  height: 13px;
}
.page-about .tl-node__icon::before,
.page-about .tl-node__icon::after {
  content: "";
  position: absolute;
  background: var(--cyan);
  transition: transform 200ms var(--ease), opacity 200ms var(--ease);
}
.page-about .tl-node__icon::before {
  top: 5.5px;
  left: 0;
  width: 13px;
  height: 2px;
}
.page-about .tl-node__icon::after {
  top: 0;
  left: 5.5px;
  width: 2px;
  height: 13px;
}
.page-about .tl-node[open] .tl-node__icon::after {
  transform: scaleY(0);
  opacity: 0;
}
.page-about .tl-node__body {
  padding: 0 16px 16px;
}
.page-about .tl-node__body p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.75;
  color: #c3d7e2;
}

/* ---------- 合作生态 ---------- */
.page-about .deliverables {
  margin-top: 26px;
}
.page-about .deliverable {
  padding: 20px 18px;
  border-top: 2px solid var(--cyan);
}
.page-about .deliverable .card__meta {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.22em;
  color: var(--muted);
}
.page-about .deliverable .card__title {
  margin: 10px 0 10px;
  font-family: var(--font-display);
  font-size: 19px;
  font-weight: 700;
  color: var(--white);
}
.page-about .deliverable p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.72;
  color: #c3d7e2;
}
.page-about .partners__note {
  margin-top: 22px !important;
  padding: 16px 18px;
  border: 1px solid var(--line);
  border-left: 2px solid var(--amber);
  background: rgba(10, 33, 54, 0.7);
  font-size: 14.5px !important;
  color: #c3d7e2 !important;
}
.page-about .partners__mail {
  font-family: var(--font-mono);
  color: var(--cyan);
  word-break: break-all;
}

/* ---------- 结尾入口 ---------- */
.page-about .about-cta {
  border-top: 1px solid var(--line);
  background:
    radial-gradient(90% 120% at 12% 0%, rgba(255, 107, 69, 0.14), transparent 60%),
    linear-gradient(180deg, var(--panel-deep) 0%, var(--ink-900) 100%);
}
.page-about .about-cta__inner {
  display: grid;
  gap: 24px;
  align-items: center;
}
.page-about .about-cta__title {
  margin: 12px 0 12px;
  font-family: var(--font-display);
  font-size: clamp(24px, 5vw, 38px);
  font-weight: 700;
  line-height: 1.16;
  letter-spacing: -0.015em;
  color: var(--white);
}
.page-about .about-cta__copy p {
  margin: 0;
  max-width: 52ch;
  font-size: 15.5px;
  line-height: 1.75;
  color: #c3d7e2;
}
.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

/* ---------- 响应式 ---------- */
@media (min-width: 720px) {
  .page-about .about-hero__inner {
    grid-template-columns: minmax(0, 1fr) minmax(260px, 0.85fr);
    align-items: end;
  }
  .page-about .step__q {
    padding: 18px 20px;
  }
  .page-about .step__a {
    padding: 0 20px 20px 52px;
  }
  .page-about .team-panel {
    padding: 26px 24px;
  }
  .page-about .deliverables {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 16px;
  }
  .page-about .about-cta__inner {
    grid-template-columns: minmax(0, 1.4fr) auto;
  }
}

@media (min-width: 980px) {
  .page-about .chapter--split {
    display: grid;
    grid-template-columns: minmax(200px, 300px) minmax(0, 1fr);
    gap: clamp(32px, 5vw, 76px);
    align-items: start;
  }
  .page-about .chapter--split .chapter__head {
    position: sticky;
    top: 108px;
    margin-bottom: 0;
  }
  .page-about .about-hero__inner {
    grid-template-columns: minmax(0, 1.55fr) minmax(300px, 0.85fr);
    gap: clamp(36px, 5vw, 72px);
  }
  .page-about .about-hero__title {
    max-width: 15ch;
  }
  .page-about .about-timeline > .timeline__item:nth-child(even) {
    margin-left: clamp(0px, 3vw, 46px);
  }
  .page-about .steps {
    gap: 16px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .step,
  .page-about .tl-node,
  .page-about .team-tabs__label,
  .page-about .breadcrumbs__link {
    transition: none;
  }
  .page-about .step:hover,
  .page-about .tl-node:hover {
    transform: none;
  }
}