.page-about {
  --about-rail-w: 148px;
  --about-gap: clamp(1.4rem, 3.2vw, 3rem);
  background: var(--night);
  color: var(--frost);
  overflow-x: clip;
}

.page-about .about-crumb {
  padding-top: clamp(1rem, 2.4vw, 1.6rem);
  padding-bottom: clamp(.4rem, 1vw, .8rem);
}

/* ---------- Hero ---------- */
.page-about .about-hero {
  position: relative;
  padding-bottom: clamp(2.4rem, 5vw, 4rem);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 62%;
  background:
    radial-gradient(120% 100% at 84% 0%, rgba(53, 240, 208, .10), transparent 62%),
    linear-gradient(180deg, rgba(15, 111, 168, .18), rgba(6, 23, 38, 0) 78%);
  pointer-events: none;
}

.page-about .about-hero__inner {
  position: relative;
  padding-bottom: clamp(1.6rem, 3.4vw, 2.6rem);
}

.page-about .about-hero .display-title {
  margin: .7rem 0 1.1rem;
  color: var(--frost);
}

.page-about .about-hero .lede {
  max-width: 62ch;
  color: rgba(242, 247, 250, .82);
}

.page-about .about-hero__facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: clamp(1.4rem, 3vw, 2.2rem) 0 0;
  padding: 0;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}

.page-about .about-fact {
  background: rgba(18, 58, 85, .58);
  padding: clamp(.8rem, 1.6vw, 1.1rem) clamp(.9rem, 1.8vw, 1.3rem);
}

.page-about .about-fact dt {
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--slate);
}

.page-about .about-fact dd {
  margin: .35rem 0 0;
  display: flex;
  align-items: baseline;
  gap: .35rem;
  color: var(--frost);
}

.page-about .about-fact dd .data-num {
  font-family: var(--font-data);
  font-size: clamp(1.5rem, 3vw, 2.1rem);
  font-weight: 700;
  color: var(--cyan);
  line-height: 1;
}

.page-about .about-fact__unit {
  font-size: 13px;
  color: var(--slate);
}

.page-about .about-hero__media {
  margin: 0;
  border: 1px solid var(--line);
}

.page-about .about-hero__media .media-frame__img {
  display: block;
  width: 100%;
  height: auto;
}

/* ---------- 长卷通用骨架 ---------- */
.page-about .about-longform {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.2rem;
}

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

.page-about .about-rail--sticky {
  align-self: start;
}

.page-about .about-rail__line {
  display: block;
  width: 1px;
  flex: 1;
  min-height: 80px;
  background: linear-gradient(180deg, var(--cyan), transparent);
}

.page-about .about-rail__ticks {
  list-style: none;
  margin: .6rem 0 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: .8rem;
  font-family: var(--font-data);
  font-size: 12px;
  color: var(--slate);
}

.page-about .about-rail__ticks li {
  display: flex;
  align-items: center;
  gap: .45rem;
}

.page-about .about-rail__tick {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  border: 1px solid var(--line-strong);
  background: transparent;
}

.page-about .about-rail__tick.is-current {
  background: var(--cyan);
  border-color: var(--cyan);
  box-shadow: 0 0 0 4px rgba(53, 240, 208, .14);
}

/* ---------- 起点 ---------- */
.page-about .about-origin {
  border-top: 1px solid var(--line);
  padding-top: clamp(2rem, 4.6vw, 3.4rem);
}

.page-about .about-body .prose p + p {
  margin-top: .95rem;
}

.page-about .about-body .section__title {
  color: var(--frost);
}

.page-about .about-origin .prose {
  color: rgba(242, 247, 250, .84);
}

/* ---------- 时间线 ---------- */
.page-about .about-track-section {
  position: relative;
  border-top: 1px solid var(--line);
}

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

.page-about .about-track::before {
  content: "";
  position: absolute;
  left: 7px;
  top: 6px;
  bottom: 6px;
  width: 1px;
  background: linear-gradient(180deg, rgba(53, 240, 208, .55), rgba(126, 150, 168, .18) 70%, transparent);
}

.page-about .about-track__item {
  position: relative;
  padding-left: 2rem;
  padding-bottom: clamp(1rem, 2.2vw, 1.6rem);
}

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

.page-about .about-track__marker {
  position: absolute;
  left: 0;
  top: 1.15rem;
  width: 15px;
  height: 15px;
  border-radius: 50%;
  background: var(--night);
  border: 1px solid var(--line-strong);
}

.page-about .about-track__item:hover .about-track__marker {
  border-color: var(--cyan);
  background: var(--cyan);
  box-shadow: 0 0 0 5px rgba(53, 240, 208, .13);
}

.page-about .about-track__card {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: clamp(.85rem, 1.8vw, 1.15rem) clamp(.95rem, 2vw, 1.35rem);
  box-shadow: var(--shadow);
  transition: border-color .18s ease, transform .18s ease;
}

.page-about .about-track__card.panel--focus {
  border-color: rgba(53, 240, 208, .5);
  background: linear-gradient(180deg, rgba(53, 240, 208, .07), rgba(18, 58, 85, .72));
}

.page-about .about-track__item:hover .about-track__card {
  border-color: rgba(53, 240, 208, .45);
  transform: translateX(2px);
}

.page-about .about-track__head {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: .55rem;
  margin-bottom: .45rem;
}

.page-about .about-track__season {
  font-family: var(--font-data);
  font-size: 15px;
  font-weight: 700;
  color: var(--cyan);
  letter-spacing: .04em;
}

.page-about .about-track__title {
  font-size: clamp(1.02rem, 1.9vw, 1.2rem);
  font-weight: 700;
  color: var(--frost);
  margin: 0;
  flex: 1 1 auto;
  min-width: 8em;
}

.page-about .about-track__card p {
  margin: 0;
  font-size: 15px;
  line-height: 1.75;
  color: rgba(242, 247, 250, .78);
}

/* ---------- 团队 ---------- */
.page-about .about-team {
  border-top: 1px solid var(--line);
}

.page-about .about-team__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--gut);
}

.page-about .about-team__media {
  margin: 0;
  border: 1px solid var(--line);
}

.page-about .about-team__media .media-frame__img {
  display: block;
  width: 100%;
  height: auto;
}

.page-about .about-team__panel {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: clamp(.95rem, 2vw, 1.4rem);
  box-shadow: var(--shadow);
}

.page-about .about-team__note {
  font-size: 13px;
  color: var(--slate);
  margin: 0 0 .85rem;
}

.page-about .about-team__panel .filter-bar {
  display: flex;
  flex-wrap: wrap;
  gap: .45rem;
  margin-bottom: 1rem;
}

.page-about .about-team__panel .filter-bar__btn {
  font: inherit;
  font-size: 13px;
  letter-spacing: .02em;
  color: var(--cyan-soft);
  background: transparent;
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: .34rem .85rem;
  cursor: pointer;
  transition: border-color .16s ease, color .16s ease, background-color .16s ease;
}

.page-about .about-team__panel .filter-bar__btn:hover {
  border-color: var(--cyan);
  color: var(--cyan);
}

.page-about .about-team__panel .filter-bar__btn[aria-pressed="true"] {
  background: rgba(53, 240, 208, .12);
  border-color: rgba(53, 240, 208, .55);
  color: var(--cyan);
}

.page-about .about-roles {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: .7rem;
}

.page-about .about-roles__item {
  border: 1px solid var(--line);
  border-left: 2px solid var(--ice);
  border-radius: var(--radius);
  padding: .85rem 1rem;
  background: rgba(6, 23, 38, .42);
  transition: border-color .16s ease, transform .16s ease;
}

.page-about .about-roles__item:hover {
  border-color: rgba(53, 240, 208, .45);
  transform: translateY(-2px);
}

.page-about .about-roles__item.is-hidden {
  display: none;
}

.page-about .about-roles__top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: .6rem;
  margin-bottom: .4rem;
}

.page-about .about-roles__count {
  font-family: var(--font-data);
  font-size: 13px;
  color: var(--slate);
}

.page-about .about-roles__title {
  margin: 0 0 .3rem;
  font-size: 1rem;
  font-weight: 700;
  color: var(--frost);
}

.page-about .about-roles__item p {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: rgba(242, 247, 250, .74);
}

.page-about .about-roles__empty {
  margin: .9rem 0 0;
  font-size: 13px;
  color: var(--amber);
}

.page-about .about-roles__empty.is-hidden {
  display: none;
}

/* ---------- 合作网络 ---------- */
.page-about .about-network {
  border-top: 1px solid var(--line);
}

.page-about .about-network__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--gut);
  align-items: start;
}

.page-about .about-rings {
  position: relative;
  width: min(100%, 380px);
  aspect-ratio: 1 / 1;
  margin: 0 auto;
}

.page-about .about-rings__circle {
  position: absolute;
  border-radius: 50%;
  border: 1px solid var(--line);
}

.page-about .about-rings__circle--outer {
  inset: 0;
  border-color: rgba(126, 150, 168, .3);
  background: radial-gradient(circle at 40% 35%, rgba(53, 240, 208, .07), transparent 68%);
}

.page-about .about-rings__circle--mid {
  inset: 17%;
  border-color: rgba(53, 240, 208, .32);
}

.page-about .about-rings__circle--inner {
  inset: 34%;
  border-color: rgba(15, 111, 168, .5);
}

.page-about .about-rings__core {
  position: absolute;
  inset: 40%;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  border-radius: 50%;
  background: rgba(18, 58, 85, .85);
  border: 1px solid rgba(53, 240, 208, .45);
}

.page-about .about-rings__core .data-big {
  font-family: var(--font-data);
  font-size: clamp(1.4rem, 3.4vw, 1.9rem);
  font-weight: 700;
  line-height: 1;
  color: var(--cyan);
}

.page-about .about-rings__cap {
  font-size: 11px;
  color: var(--slate);
  margin-top: .18rem;
  letter-spacing: .04em;
}

.page-about .about-rings__pin {
  position: absolute;
  font-size: 12px;
  line-height: 1.4;
  color: rgba(242, 247, 250, .8);
  background: rgba(6, 23, 38, .86);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: .28rem .55rem;
  white-space: nowrap;
  transition: border-color .16s ease, color .16s ease;
}

.page-about .about-rings__pin b {
  font-family: var(--font-data);
  color: var(--cyan);
  margin-right: .18rem;
}

.page-about .about-rings__pin:hover {
  border-color: var(--cyan);
  color: var(--frost);
}

.page-about .about-rings__pin--a {
  top: 4%;
  left: 50%;
  transform: translateX(-50%);
}

.page-about .about-rings__pin--b {
  bottom: 8%;
  left: 2%;
}

.page-about .about-rings__pin--c {
  bottom: 8%;
  right: 2%;
}

.page-about .about-network__panel {
  background: rgba(18, 58, 85, .5);
  border: 1px dashed var(--line-strong);
  border-radius: var(--radius);
  padding: clamp(.95rem, 2vw, 1.4rem);
}

.page-about .about-network__panel .panel__title {
  color: var(--frost);
  margin: 0 0 .6rem;
}

.page-about .about-network__panel p {
  font-size: 15px;
  line-height: 1.78;
  color: rgba(242, 247, 250, .8);
  margin: 0 0 .7rem;
}

.page-about .about-network__link {
  margin-top: .3rem;
}

.page-about .about-network__media {
  margin: 0;
  border: 1px solid var(--line);
}

.page-about .about-network__media .media-frame__img {
  display: block;
  width: 100%;
  height: auto;
}

/* ---------- 更新节奏（浅色分区） ---------- */
.page-about.section--light,
.page-about .section--light.about-service {
  background: var(--frost);
  color: var(--ink);
}

.page-about .about-service .section__title {
  color: var(--ink);
}

.page-about .about-service .eyebrow--dark {
  color: var(--ice);
}

.page-about .about-cadence {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  background: rgba(10, 17, 25, .12);
  border: 1px solid rgba(10, 17, 25, .12);
  border-radius: var(--radius);
  overflow: hidden;
}

.page-about .about-cadence__item {
  background: var(--frost);
  padding: clamp(.9rem, 2vw, 1.25rem);
  transition: background-color .16s ease;
}

.page-about .about-cadence__item:hover {
  background: #fff;
}

.page-about .about-cadence__freq {
  display: inline-block;
  font-family: var(--font-data);
  font-size: 15px;
  font-weight: 700;
  color: var(--ice);
  border-bottom: 2px solid var(--cyan);
  padding-bottom: .1rem;
}

.page-about .about-cadence__title {
  margin: .5rem 0 .3rem;
  font-size: 1rem;
  font-weight: 700;
  color: var(--ink);
}

.page-about .about-cadence__item p {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: #40515f;
}

.page-about .about-service__note {
  margin-top: clamp(1.1rem, 2.4vw, 1.6rem);
  padding-left: 1rem;
  border-left: 2px solid var(--ice);
}

.page-about .about-service__note p {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: #40515f;
}

/* ---------- 下一步 ---------- */
.page-about .about-next {
  border-top: 1px solid var(--line);
}

.page-about .about-next__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--gut);
}

.page-about .about-next__card {
  position: relative;
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 1.6rem 1.1rem 1.1rem;
  box-shadow: var(--shadow);
  transition: border-color .18s ease, transform .18s ease;
}

.page-about .about-next__card:hover {
  border-color: rgba(53, 240, 208, .45);
  transform: translateY(-2px);
}

.page-about .about-next__card .annot--tag {
  position: absolute;
  top: -.68rem;
  left: 1rem;
  background: var(--night);
  border: 1px solid var(--line-strong);
  border-radius: 999px;
  padding: .1rem .6rem;
  font-size: 11px;
  letter-spacing: .06em;
  color: var(--cyan-soft);
}

.page-about .about-next__card .panel__title {
  color: var(--frost);
  margin: 0 0 .5rem;
  font-size: 1.02rem;
}

.page-about .about-next__card p {
  margin: 0;
  font-size: 14px;
  line-height: 1.72;
  color: rgba(242, 247, 250, .76);
}

.page-about .about-next__cta {
  display: flex;
  flex-wrap: wrap;
  gap: .7rem;
  margin-top: clamp(1.4rem, 3vw, 2rem);
}

/* ---------- 响应式 ---------- */
@media (min-width: 620px) {
  .page-about .about-hero__facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .about-cadence {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-about .about-next__grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 900px) {
  .page-about .about-longform {
    grid-template-columns: var(--about-rail-w) minmax(0, 1fr);
    gap: var(--about-gap);
  }

  .page-about .about-rail {
    display: flex;
    flex-direction: column;
    gap: .5rem;
    padding-top: .3rem;
  }

  .page-about .about-rail--sticky {
    position: sticky;
    top: calc(var(--cmd-h) + 1.6rem);
  }

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

  .page-about .about-network__grid {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, 1fr);
    grid-template-areas:
      "rings panel"
      "media panel";
    gap: var(--about-gap) var(--gut);
  }

  .page-about .about-rings {
    grid-area: rings;
    margin: 0;
  }

  .page-about .about-network__panel {
    grid-area: panel;
  }

  .page-about .about-network__media {
    grid-area: media;
  }

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

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

@media (min-width: 1180px) {
  .page-about {
    --about-rail-w: 176px;
  }

  .page-about .about-track__item {
    padding-left: 2.4rem;
  }

  .page-about .about-track::before {
    left: 8px;
  }

  .page-about .about-track__marker {
    left: 1px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-track__card,
  .page-about .about-roles__item,
  .page-about .about-next__card,
  .page-about .about-rings__pin,
  .page-about .about-cadence__item {
    transition: none;
  }

  .page-about .about-track__item:hover .about-track__card,
  .page-about .about-roles__item:hover,
  .page-about .about-next__card:hover {
    transform: none;
  }
}