.page-about {
  --about-gap: 22px;
  --about-inner: min(100% - 40px, 1180px);
  background: var(--ink);
  color: var(--cold);
}

.page-about .container {
  width: var(--about-inner);
  margin-inline: auto;
}

.page-about .breadcrumbs {
  padding: 18px 0 10px;
  font-family: var(--font-num);
  font-size: 12.5px;
  letter-spacing: .02em;
  color: var(--muted);
}

.page-about .breadcrumbs a {
  color: var(--lime);
  text-decoration: none;
}

.page-about .breadcrumbs a:hover,
.page-about .breadcrumbs a:focus-visible {
  color: var(--paper);
  text-decoration: underline;
}

/* ---------- 封面 ---------- */
.about-cover {
  position: relative;
  border-bottom: 1px solid var(--line);
  background:
    radial-gradient(130% 90% at 92% -10%, rgba(31, 79, 168, .5) 0%, rgba(5, 10, 22, 0) 58%),
    linear-gradient(180deg, var(--deep) 0%, var(--ink) 76%);
  overflow: hidden;
}

.about-cover__grid {
  display: grid;
  gap: var(--about-gap);
  padding: 18px 0 6px;
}

.about-cover h1 {
  font-family: var(--font-head);
  font-weight: 900;
  letter-spacing: -.025em;
  font-size: clamp(30px, 7.2vw, 62px);
  line-height: 1.06;
  margin: .38em 0 .5em;
  color: var(--paper);
}

.about-cover .lede {
  font-size: clamp(15.5px, 2.4vw, 18px);
  line-height: 1.78;
  color: #c9d4e4;
  max-width: 40em;
  margin: 0;
}

.about-cover__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 24px;
}

.about-cover__aside {
  border: var(--bw) solid var(--line);
  background: rgba(14, 29, 58, .72);
  padding: 18px 18px 10px;
  box-shadow: var(--shadow-card);
}

.about-cover__eyebrow {
  font-size: 12px;
  letter-spacing: .12em;
  color: var(--lime);
  margin: 0 0 12px;
}

.about-stats {
  list-style: none;
  margin: 0;
  padding: 0;
}

.about-stat {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding: 10px 0;
  border-top: 1px solid var(--line);
}

.about-stat__value {
  font-size: clamp(24px, 5.4vw, 34px);
  font-weight: 800;
  line-height: 1;
  color: var(--lime);
  flex: 0 0 auto;
}

.about-stat__unit {
  font-size: 12.5px;
  line-height: 1.5;
  color: var(--muted);
}

.about-index {
  display: flex;
  gap: 8px;
  overflow-x: auto;
  padding: 16px 0 24px;
  margin-top: 14px;
  border-top: 1px solid var(--line);
  scrollbar-width: thin;
}

.about-index a {
  flex: 0 0 auto;
  font-family: var(--font-num);
  font-size: 12.5px;
  letter-spacing: .02em;
  color: var(--cold);
  text-decoration: none;
  border: 2px solid var(--line);
  background: rgba(255, 255, 255, .03);
  padding: 8px 12px;
  transition: border-color var(--dur) var(--ease), color var(--dur) var(--ease), background var(--dur) var(--ease);
}

.about-index a:hover,
.about-index a:focus-visible {
  border-color: var(--lime);
  color: var(--lime);
  background: rgba(168, 255, 46, .08);
}

/* ---------- 通用章节微调 ---------- */
.page-about .section {
  padding: 52px 0;
}

.page-about .section-head h2 {
  font-family: var(--font-head);
  font-weight: 900;
  letter-spacing: -.02em;
  font-size: clamp(23px, 4.4vw, 42px);
  line-height: 1.14;
  margin: 10px 0 12px;
  color: var(--paper);
}

.page-about .section-head > p:last-child {
  max-width: 44em;
  line-height: 1.78;
  color: #bcc7d8;
  margin: 0;
}

/* ---------- 时间轴 ---------- */
.about-timeline {
  list-style: none;
  margin: 34px 0 0;
  padding: 0;
  position: relative;
}

.about-timeline::before {
  content: "";
  position: absolute;
  left: 8px;
  top: 6px;
  bottom: 6px;
  width: 2px;
  background: linear-gradient(180deg, var(--lime) 0%, var(--steel) 55%, var(--line) 100%);
}

.about-timeline__item {
  position: relative;
  padding-left: 34px;
  margin-bottom: 16px;
}

.about-timeline__item::before {
  content: "";
  position: absolute;
  left: 1px;
  top: 22px;
  width: 12px;
  height: 12px;
  background: var(--lime);
  border: 3px solid var(--ink);
  box-sizing: content-box;
}

.about-tl {
  border: var(--bw) solid var(--line);
  background: var(--deep);
  box-shadow: var(--shadow-card);
  transition: border-color var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.about-tl:hover,
.about-tl:focus-within {
  border-color: var(--lime);
  transform: translate(-2px, -2px);
}

.about-tl[open] {
  border-color: var(--lime);
}

.about-tl__head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 10px 14px;
  padding: 16px 18px;
  cursor: pointer;
  list-style: none;
}

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

.about-tl__year {
  font-size: 13px;
  font-weight: 700;
  color: var(--ink);
  background: var(--lime);
  padding: 3px 9px;
  letter-spacing: .02em;
}

.about-tl__title {
  flex: 1 1 12em;
  font-family: var(--font-head);
  font-weight: 900;
  letter-spacing: -.01em;
  font-size: clamp(16px, 2.8vw, 21px);
  color: var(--paper);
}

.about-tl__more {
  font-size: 11.5px;
  letter-spacing: .12em;
  color: var(--muted);
}

.about-tl[open] .about-tl__more {
  color: var(--orange);
}

.about-tl__body {
  padding: 0 18px 18px;
  border-top: 1px solid var(--line);
}

.about-tl__body p {
  margin: 14px 0 0;
  font-size: 15px;
  line-height: 1.8;
  color: #bcc7d8;
  max-width: 40em;
}

.about-tl__body a,
.about-link {
  color: var(--lime);
  text-decoration: none;
  border-bottom: 1px solid rgba(168, 255, 46, .5);
}

.about-tl__body a:hover,
.about-link:hover {
  color: var(--paper);
  border-bottom-color: var(--paper);
}

/* ---------- 团队 ---------- */
.about-team {
  display: grid;
  gap: 26px;
  margin-top: 30px;
}

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

.about-role {
  border: var(--bw) solid var(--line);
  background: var(--deep);
  padding: 18px;
  box-shadow: var(--shadow-card);
  transition: border-color var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.about-role:hover,
.about-role:focus-within,
.about-role:focus {
  border-color: var(--lime);
  transform: translate(-2px, -2px);
}

.about-role__head {
  display: flex;
  align-items: baseline;
  gap: 14px;
}

.about-role__num {
  font-size: clamp(30px, 6vw, 44px);
  font-weight: 800;
  line-height: 1;
  color: var(--lime);
}

.about-role__name {
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(17px, 3vw, 21px);
  letter-spacing: -.01em;
  margin: 0;
  color: var(--paper);
}

.about-role__line {
  margin: 12px 0 0;
  font-size: 14.5px;
  line-height: 1.72;
  color: #aab6c9;
}

.about-role__more {
  max-height: 0;
  overflow: hidden;
  opacity: 0;
  transition: max-height .28s var(--ease), opacity .2s var(--ease), margin .28s var(--ease);
}

.about-role:hover .about-role__more,
.about-role:focus-within .about-role__more,
.about-role:focus .about-role__more {
  max-height: 22em;
  opacity: 1;
  margin-top: 4px;
}

.about-role__more p {
  margin: 10px 0 0;
  padding-left: 12px;
  border-left: 3px solid var(--lime);
  font-size: 14px;
  line-height: 1.78;
  color: #c3cddb;
}

.about-team__figure {
  margin: 0;
}

.about-team__figure .note {
  margin-top: 16px;
}

/* ---------- 流程（冷白章节） ---------- */
.page-about .section--paper {
  background: var(--cold);
  color: var(--ink);
}

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

.page-about .section--paper .section-head > p:last-child {
  color: #3b4557;
}

.page-about .section--paper .kicker {
  color: var(--lime-deep);
}

.about-flow {
  display: grid;
  gap: 14px;
  margin-top: 28px;
}

.about-step {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 14px;
  border: var(--bw) solid var(--ink);
  background: var(--paper);
  padding: 16px;
  box-shadow: 6px 6px 0 rgba(5, 10, 22, .16);
  transition: box-shadow var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.about-step:hover {
  transform: translate(-2px, -2px);
  box-shadow: 8px 8px 0 rgba(78, 143, 0, .35);
}

.about-step__num {
  font-size: 22px;
  font-weight: 800;
  line-height: 1;
  color: var(--ink);
  background: var(--lime);
  padding: 6px 9px;
  align-self: start;
}

.about-step h3 {
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(16px, 3vw, 20px);
  letter-spacing: -.01em;
  margin: 0 0 6px;
  color: var(--ink);
}

.about-step__time {
  margin: 0 0 8px;
  font-size: 12.5px;
  letter-spacing: .04em;
  color: var(--steel);
}

.about-step__body p:last-child {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.76;
  color: #333e52;
}

.about-flow__foot {
  display: grid;
  gap: 22px;
  margin-top: 28px;
}

.about-flow__side {
  border-top: 1px solid rgba(5, 10, 22, .18);
  padding-top: 16px;
}

.about-flow__lead {
  margin: 0 0 12px;
  font-size: 14.5px;
  line-height: 1.8;
  color: #333e52;
}

.about-flow__side .about-link {
  color: var(--lime-deep);
  border-bottom-color: rgba(78, 143, 0, .45);
}

.about-flow__side .about-link:hover {
  color: var(--ink);
  border-bottom-color: var(--ink);
}

/* ---------- 合作网络 ---------- */
.about-net {
  display: grid;
  gap: 26px;
  margin-top: 30px;
}

.about-net__figure {
  margin: 0;
}

.about-cells {
  display: grid;
  grid-template-columns: repeat(10, 1fr);
  gap: 5px;
  margin-top: 16px;
}

.about-cell {
  aspect-ratio: 1 / 1;
  background: rgba(135, 146, 166, .16);
  border: 1px solid var(--line);
}

.about-cell.is-on {
  background: var(--lime);
  border-color: var(--lime-deep);
}

.about-net__stats {
  list-style: none;
  margin: 0 0 22px;
  padding: 0;
}

.about-net__stat {
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding: 12px 0;
  border-bottom: 1px solid var(--line);
}

.about-net__num {
  flex: 0 0 auto;
  font-size: clamp(22px, 4.6vw, 32px);
  font-weight: 800;
  line-height: 1;
  color: var(--lime);
}

.about-net__txt {
  font-size: 14px;
  line-height: 1.68;
  color: #bcc7d8;
}

.about-net__qual {
  border: var(--bw) solid var(--orange);
  background: rgba(255, 75, 31, .07);
  padding: 16px 18px;
  box-shadow: var(--shadow-deep);
}

.about-net__qual-tag {
  margin: 0 0 8px;
  font-size: 11.5px;
  letter-spacing: .14em;
  color: var(--orange);
}

.about-net__qual h3 {
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(16px, 3vw, 20px);
  letter-spacing: -.01em;
  line-height: 1.35;
  margin: 0 0 10px;
  color: var(--paper);
}

.about-net__qual p:last-child {
  margin: 0;
  font-size: 14px;
  line-height: 1.76;
  color: #c3cddb;
}

.about-net__types {
  list-style: none;
  margin: 22px 0 0;
  padding: 0;
  display: grid;
  gap: 10px;
}

.about-net__types li {
  border-left: 3px solid var(--steel);
  padding: 2px 0 2px 12px;
  font-size: 14px;
  line-height: 1.72;
  color: #aab6c9;
}

.about-net__types strong {
  color: var(--paper);
  font-weight: 700;
}

.about-net__cta {
  margin: 22px 0 0;
}

/* ---------- 下一步 ---------- */
.about-next {
  margin-top: 30px;
}

.about-next__card {
  border: var(--bw) solid var(--line);
  background: var(--deep);
  padding: 18px;
  box-shadow: var(--shadow-card);
  transition: border-color var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.about-next__card:hover {
  border-color: var(--lime);
  transform: translate(-2px, -2px);
}

.about-next__tag {
  margin: 0 0 10px;
  font-size: 11.5px;
  letter-spacing: .12em;
  color: var(--lime);
}

.about-next__card h3 {
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(16px, 3vw, 20px);
  letter-spacing: -.01em;
  line-height: 1.32;
  margin: 0 0 10px;
  color: var(--paper);
}

.about-next__card p {
  margin: 0 0 10px;
  font-size: 14px;
  line-height: 1.76;
  color: #bcc7d8;
}

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

.about-cta {
  margin-top: 30px;
  border: var(--bw) solid var(--lime);
  background: linear-gradient(120deg, rgba(168, 255, 46, .12) 0%, rgba(31, 79, 168, .22) 100%);
  padding: 22px;
  display: grid;
  gap: 18px;
  box-shadow: var(--shadow-lime);
}

.about-cta h3 {
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(19px, 3.4vw, 26px);
  letter-spacing: -.015em;
  margin: 0 0 8px;
  color: var(--paper);
}

.about-cta p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.76;
  color: #c9d4e4;
  max-width: 40em;
}

.about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

/* ---------- 桌面栅格 ---------- */
@media (min-width: 720px) {
  .about-cover__grid {
    padding: 26px 0 10px;
  }

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

  .about-flow__foot {
    grid-template-columns: 3fr 2fr;
    align-items: start;
  }

  .about-flow__side {
    border-top: 0;
    border-left: 1px solid rgba(5, 10, 22, .18);
    padding: 4px 0 0 22px;
  }

  .about-cta {
    grid-template-columns: 1fr auto;
    align-items: center;
  }
}

@media (min-width: 900px) {
  .page-about .section {
    padding: 72px 0;
  }

  .about-cover__grid {
    grid-template-columns: 7fr 4fr;
    gap: 40px;
    align-items: end;
  }

  .about-cover__aside {
    margin-bottom: 8px;
  }

  .about-timeline::before {
    left: 50%;
    transform: translateX(-1px);
  }

  .about-timeline__item {
    width: 50%;
    padding-left: 0;
    padding-right: 46px;
    margin-bottom: 22px;
  }

  .about-timeline__item:nth-child(even) {
    margin-left: 50%;
    padding-left: 46px;
    padding-right: 0;
  }

  .about-timeline__item::before {
    left: auto;
    right: -10px;
  }

  .about-timeline__item:nth-child(even)::before {
    left: -10px;
    right: auto;
  }
}

@media (min-width: 980px) {
  .about-team {
    grid-template-columns: 7fr 5fr;
    align-items: start;
  }

  .about-net {
    grid-template-columns: 6fr 6fr;
    align-items: start;
  }

  .about-cells {
    grid-template-columns: repeat(10, 1fr);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about * {
    transition-duration: .01ms !important;
  }

  .about-role__more {
    max-height: none;
    opacity: 1;
  }
}