.page-about {
  --about-line-gap: clamp(1.75rem, 4vw, 3rem);
  --about-dot: 16px;
}

/* ===== 首屏 ===== */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding-block: clamp(1.75rem, 5vw, 3rem) clamp(2.5rem, 6vw, 4.75rem);
  border-bottom: 1px solid var(--gch-line);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  top: -16%;
  right: -22%;
  width: min(540px, 82vw);
  aspect-ratio: 1;
  background: linear-gradient(140deg, rgba(242, 183, 5, 0.26), rgba(31, 200, 219, 0.09) 58%, transparent 72%);
  border-radius: 44% 56% 62% 38% / 46% 36% 64% 54%;
  transform: rotate(-10deg);
  pointer-events: none;
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  left: -8%;
  bottom: -26%;
  width: 46%;
  height: 62%;
  background: linear-gradient(150deg, rgba(31, 200, 219, 0.16), rgba(61, 240, 165, 0.04) 70%, transparent);
  border-radius: 38% 62% 55% 45% / 52% 44% 56% 48%;
  transform: rotate(13deg);
  pointer-events: none;
}

.page-about .about-hero .gch-container {
  position: relative;
  z-index: 1;
}

.page-about .about-hero .gch-breadcrumb {
  margin-bottom: clamp(1.25rem, 3vw, 2rem);
}

.page-about .about-hero__grid {
  display: grid;
  gap: var(--about-line-gap);
}

.page-about .about-hero__title {
  margin: 0.55rem 0 0;
  font-size: clamp(2.05rem, 7.2vw, 4.35rem);
  line-height: 1.05;
  letter-spacing: -0.02em;
}

.page-about .about-hero__lead {
  margin: clamp(1rem, 2.4vw, 1.5rem) 0 0;
  max-width: 60ch;
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: clamp(1.35rem, 3vw, 2rem);
}

.page-about .about-hero__facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--gch-line);
  border: 1px solid var(--gch-line);
  border-radius: var(--gch-radius);
  overflow: hidden;
  align-self: end;
}

.page-about .about-hero__fact {
  background: linear-gradient(180deg, rgba(19, 41, 75, 0.96), rgba(11, 27, 51, 0.96));
  padding: 1.05rem 1.1rem 1.15rem;
  display: flex;
  flex-direction: column;
  gap: 0.3rem;
}

.page-about .about-hero__fact:first-child {
  background: linear-gradient(150deg, rgba(242, 183, 5, 0.18), rgba(19, 41, 75, 0.96) 62%);
}

.page-about .about-hero__fact-num {
  font-size: clamp(1.3rem, 3.4vw, 1.75rem);
  color: var(--gch-gold);
  line-height: 1.1;
}

.page-about .about-hero__fact-label {
  font-size: 0.82rem;
  color: var(--gch-steel);
  line-height: 1.45;
}

/* ===== 通用小标题 ===== */
.page-about .about-h2 {
  margin: 0.5rem 0 0;
  font-size: clamp(1.55rem, 4.4vw, 2.5rem);
  line-height: 1.18;
  letter-spacing: -0.015em;
}

.page-about .about-p {
  margin: 0.9rem 0 0;
  max-width: 62ch;
  font-size: 0.97rem;
  line-height: 1.75;
  color: var(--gch-mist);
}

.page-about .about-lead {
  margin: 0.9rem 0 0;
  max-width: 62ch;
  font-size: clamp(0.95rem, 2.2vw, 1.05rem);
  line-height: 1.75;
  color: rgba(230, 237, 247, 0.82);
}

/* ===== 团队 ===== */
.page-about .about-team__grid {
  display: grid;
  gap: var(--about-line-gap);
}

.page-about .about-team__figure {
  margin: clamp(1.5rem, 3.5vw, 2.25rem) 0 0;
}

.page-about .about-team__cards {
  display: grid;
  gap: 1rem;
}

.page-about .about-role {
  position: relative;
  padding: 1.3rem 1.25rem 1.35rem;
  background: var(--gch-navy-2);
  border: 1px solid var(--gch-line);
  border-radius: var(--gch-radius-sm);
  transition: transform 0.25s var(--gch-ease), border-color 0.25s var(--gch-ease);
}

.page-about .about-role::before {
  content: "";
  position: absolute;
  left: 1.25rem;
  top: 0;
  width: 30px;
  height: 3px;
  border-radius: 0 0 3px 3px;
  background: var(--gch-gold);
  transition: width 0.28s var(--gch-ease), background-color 0.28s var(--gch-ease);
}

.page-about .about-role:hover,
.page-about .about-role:focus-within {
  transform: translateY(-4px);
  border-color: var(--gch-line-strong);
}

.page-about .about-role:hover::before,
.page-about .about-role:focus-within::before {
  width: 72px;
  background: var(--gch-cyan);
}

.page-about .about-role__title {
  margin: 0.75rem 0 0;
  font-size: clamp(1.02rem, 2.4vw, 1.15rem);
  line-height: 1.4;
  color: var(--gch-mist);
}

.page-about .about-role__text {
  margin: 0.55rem 0 0;
  font-size: 0.9rem;
  line-height: 1.7;
  color: rgba(230, 237, 247, 0.72);
}

/* ===== 发展历程 ===== */
.page-about .about-timeline__head {
  display: grid;
  gap: clamp(1.5rem, 3.5vw, 2.5rem);
}

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

.page-about .about-timeline__body {
  display: grid;
  gap: clamp(1.5rem, 3.5vw, 2.5rem);
  margin-top: clamp(2rem, 4.5vw, 3rem);
}

.page-about .about-rail {
  display: flex;
  gap: 0.5rem;
  overflow-x: auto;
  padding-bottom: 0.6rem;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: thin;
}

.page-about .about-rail__item {
  flex: 0 0 auto;
  display: inline-flex;
  align-items: baseline;
  gap: 0.5rem;
  padding: 0.5rem 0.85rem;
  border: 1px solid var(--gch-line);
  border-radius: 999px;
  background: rgba(19, 41, 75, 0.6);
  color: var(--gch-mist);
  text-decoration: none;
  font-size: 0.85rem;
  white-space: nowrap;
  transition: color 0.22s var(--gch-ease), border-color 0.22s var(--gch-ease), background-color 0.22s var(--gch-ease);
}

.page-about .about-rail__item .gch-num {
  color: var(--gch-gold);
  font-size: 0.78rem;
}

.page-about .about-rail__item:hover,
.page-about .about-rail__item:focus-visible {
  color: var(--gch-cyan);
  border-color: rgba(31, 200, 219, 0.5);
  background: rgba(31, 200, 219, 0.08);
}

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

.page-about .about-steps::before {
  content: "";
  position: absolute;
  left: calc(var(--about-dot) / 2);
  top: 0.75rem;
  bottom: 1.5rem;
  width: 2px;
  background: linear-gradient(180deg, var(--gch-gold), rgba(31, 200, 219, 0.4) 58%, rgba(123, 138, 163, 0.05));
}

.page-about .about-step {
  position: relative;
  padding: 0 0 clamp(1.6rem, 3.5vw, 2.25rem) calc(var(--about-dot) + 1.6rem);
}

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

.page-about .about-step::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.35rem;
  width: var(--about-dot);
  height: var(--about-dot);
  border-radius: 50%;
  background: var(--gch-navy);
  border: 2px solid var(--gch-gold);
  box-shadow: 0 0 0 4px rgba(242, 183, 5, 0.09);
  transition: border-color 0.25s var(--gch-ease), box-shadow 0.25s var(--gch-ease);
}

.page-about .about-step:target::before,
.page-about .about-step:hover::before {
  border-color: var(--gch-mint);
  box-shadow: 0 0 0 6px rgba(61, 240, 165, 0.12);
}

.page-about .about-step__version {
  display: inline-block;
  font-family: var(--gch-font-mono);
  font-size: 0.76rem;
  letter-spacing: 0.14em;
  color: var(--gch-gold);
  border-bottom: 2px solid rgba(242, 183, 5, 0.35);
  padding-bottom: 0.15rem;
}

.page-about .about-step__title {
  margin: 0.6rem 0 0;
  font-size: clamp(1.1rem, 2.8vw, 1.4rem);
  line-height: 1.35;
}

.page-about .about-step__text {
  margin: 0.6rem 0 0;
  max-width: 58ch;
  font-size: 0.94rem;
  line-height: 1.75;
  color: rgba(230, 237, 247, 0.78);
}

.page-about .about-step__tags {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin: 0.85rem 0 0;
  padding: 0;
}

/* ===== 内容制作 ===== */
.page-about .about-flow {
  list-style: none;
  margin: clamp(2rem, 4vw, 3rem) 0 0;
  padding: 0;
  display: grid;
  gap: 1rem;
  counter-reset: aboutflow;
}

.page-about .about-flow__item {
  position: relative;
  padding: 1.3rem 1.25rem 1.4rem;
  border: 1px solid var(--gch-line);
  border-radius: var(--gch-radius-sm);
  background:
    linear-gradient(180deg, rgba(19, 41, 75, 0.9), rgba(11, 27, 51, 0.75));
  transition: border-color 0.25s var(--gch-ease), transform 0.25s var(--gch-ease);
}

.page-about .about-flow__item::after {
  content: "";
  position: absolute;
  inset: auto 0 0 0;
  height: 3px;
  border-radius: 0 0 var(--gch-radius-sm) var(--gch-radius-sm);
  background: linear-gradient(90deg, var(--gch-gold), rgba(31, 200, 219, 0.6) 55%, transparent);
  opacity: 0.45;
  transition: opacity 0.25s var(--gch-ease);
}

.page-about .about-flow__item:hover {
  border-color: var(--gch-line-strong);
  transform: translateY(-4px);
}

.page-about .about-flow__item:hover::after {
  opacity: 1;
}

.page-about .about-flow__no {
  font-size: 1.5rem;
  color: var(--gch-gold-2);
  line-height: 1;
}

.page-about .about-flow__title {
  margin: 0.7rem 0 0;
  font-size: clamp(1.02rem, 2.4vw, 1.2rem);
}

.page-about .about-flow__text {
  margin: 0.5rem 0 0;
  font-size: 0.9rem;
  line-height: 1.72;
  color: rgba(230, 237, 247, 0.74);
}

/* ===== 覆盖项目 ===== */
.page-about .about-coverage__grid {
  display: grid;
  gap: clamp(1.75rem, 4vw, 2.75rem);
  margin-top: clamp(2rem, 4vw, 3rem);
}

.page-about .about-tabs .gch-tabs__list {
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem;
  padding-bottom: 0.85rem;
  border-bottom: 1px solid var(--gch-line);
  margin-bottom: 1.35rem;
}

.page-about .about-tabs .gch-tabs__btn {
  border-radius: 999px;
  padding: 0.45rem 1rem;
  font-size: 0.9rem;
  transition: color 0.22s var(--gch-ease), background-color 0.22s var(--gch-ease), border-color 0.22s var(--gch-ease);
}

.page-about .about-tabs .gch-tabs__btn[aria-selected="true"] {
  background: rgba(242, 183, 5, 0.14);
  border-color: rgba(242, 183, 5, 0.55);
  color: var(--gch-gold-2);
}

.page-about .about-tabs .gch-tabs__btn:hover {
  color: var(--gch-cyan);
}

.page-about .about-panel__title {
  margin: 0;
  font-size: clamp(1.12rem, 2.8vw, 1.42rem);
  line-height: 1.35;
}

.page-about .about-panel__text {
  margin: 0.7rem 0 0;
  max-width: 56ch;
  font-size: 0.94rem;
  line-height: 1.78;
  color: rgba(230, 237, 247, 0.8);
}

.page-about .about-panel__list {
  list-style: none;
  margin: 1.05rem 0 0;
  padding: 0;
  display: grid;
  gap: 0.55rem;
}

.page-about .about-panel__list li {
  position: relative;
  padding-left: 1.15rem;
  font-size: 0.9rem;
  line-height: 1.68;
  color: rgba(230, 237, 247, 0.72);
}

.page-about .about-panel__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.6em;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--gch-gold);
}

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

/* ===== 合作伙伴 ===== */
.page-about .about-partners__grid {
  display: grid;
  gap: 1rem;
  margin-top: clamp(2rem, 4vw, 3rem);
}

.page-about .about-partner {
  position: relative;
  padding: 1.4rem 1.3rem 1.5rem;
  border: 1px solid var(--gch-line);
  border-radius: var(--gch-radius);
  background: linear-gradient(165deg, rgba(19, 41, 75, 0.92), rgba(11, 27, 51, 0.72));
  overflow: hidden;
  transition: border-color 0.25s var(--gch-ease), transform 0.25s var(--gch-ease);
}

.page-about .about-partner::before {
  content: "";
  position: absolute;
  top: -30%;
  right: -22%;
  width: 62%;
  aspect-ratio: 1;
  border-radius: 46% 54% 60% 40% / 52% 42% 58% 48%;
  background: radial-gradient(circle at 40% 40%, rgba(31, 200, 219, 0.16), transparent 68%);
  pointer-events: none;
}

.page-about .about-partner:hover {
  border-color: var(--gch-line-strong);
  transform: translateY(-4px);
}

.page-about .about-partner__title {
  margin: 0.85rem 0 0;
  font-size: clamp(1.05rem, 2.5vw, 1.25rem);
  line-height: 1.38;
}

.page-about .about-partner__text {
  margin: 0.6rem 0 0;
  font-size: 0.9rem;
  line-height: 1.74;
  color: rgba(230, 237, 247, 0.74);
}

/* ===== 认可与里程碑 ===== */
.page-about .about-credit__panel {
  display: grid;
  gap: clamp(1.75rem, 4vw, 3rem);
  padding: clamp(1.5rem, 4vw, 2.75rem);
  border: 1px solid var(--gch-line);
  border-radius: var(--gch-radius);
  background:
    radial-gradient(circle at 88% 8%, rgba(242, 183, 5, 0.14), transparent 58%),
    linear-gradient(160deg, rgba(19, 41, 75, 0.92), rgba(11, 27, 51, 0.8));
}

.page-about .about-credit__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--gch-line);
  border: 1px solid var(--gch-line);
  border-radius: var(--gch-radius-sm);
  overflow: hidden;
}

.page-about .about-credit__item {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
  padding: 1.05rem 1.15rem 1.15rem;
  background: rgba(11, 27, 51, 0.85);
}

.page-about .about-credit__num {
  font-size: clamp(1.25rem, 3.2vw, 1.65rem);
  color: var(--gch-mint);
  line-height: 1.1;
}

.page-about .about-credit__item:nth-child(2) .about-credit__num {
  color: var(--gch-gold);
}

.page-about .about-credit__item:nth-child(4) .about-credit__num {
  color: var(--gch-cyan);
}

.page-about .about-credit__label {
  font-size: 0.88rem;
  line-height: 1.65;
  color: rgba(230, 237, 247, 0.74);
}

/* ===== 下一步 ===== */
.page-about .about-next__panel {
  position: relative;
  display: grid;
  gap: clamp(1.35rem, 3vw, 2.25rem);
  padding: clamp(1.5rem, 4vw, 2.75rem);
  border: 1px solid var(--gch-line-strong);
  border-radius: var(--gch-radius);
  background:
    linear-gradient(120deg, rgba(242, 183, 5, 0.12), rgba(11, 27, 51, 0.86) 46%, rgba(31, 200, 219, 0.1));
  overflow: hidden;
}

.page-about .about-next__panel::after {
  content: "";
  position: absolute;
  left: -6%;
  bottom: -34%;
  width: 42%;
  height: 88%;
  background: rgba(31, 200, 219, 0.09);
  border-radius: 44% 56% 62% 38% / 48% 40% 60% 52%;
  transform: rotate(11deg);
  pointer-events: none;
}

.page-about .about-next__panel > * {
  position: relative;
  z-index: 1;
}

.page-about .about-next__links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  align-content: start;
}

/* ===== 平板及以上 ===== */
@media (min-width: 700px) {
  .page-about .about-team__cards {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-about .about-timeline__head {
    grid-template-columns: minmax(0, 1.35fr) minmax(0, 1fr);
    align-items: start;
  }

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

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

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

/* ===== 桌面端 ===== */
@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.55fr) minmax(0, 1fr);
    align-items: end;
    gap: clamp(2rem, 5vw, 4rem);
  }

  .page-about .about-team__grid {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.05fr);
    align-items: start;
    gap: clamp(2.25rem, 5vw, 3.75rem);
  }

  .page-about .about-team__cards {
    gap: 1.1rem;
  }

  .page-about .about-timeline__body {
    grid-template-columns: 208px minmax(0, 1fr);
    gap: clamp(2rem, 5vw, 3.5rem);
    align-items: start;
  }

  .page-about .about-rail {
    position: sticky;
    top: calc(var(--gch-header-h) + 1.5rem);
    flex-direction: column;
    gap: 0.15rem;
    overflow: visible;
    padding: 0 0 0 1.1rem;
    border-left: 2px solid var(--gch-line);
  }

  .page-about .about-rail__item {
    border: 0;
    border-radius: 0;
    background: transparent;
    padding: 0.5rem 0.25rem;
    white-space: normal;
    font-size: 0.9rem;
  }

  .page-about .about-rail__item:hover,
  .page-about .about-rail__item:focus-visible {
    background: transparent;
    border-color: transparent;
  }

  .page-about .about-flow {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 1.1rem;
  }

  .page-about .about-coverage__grid {
    grid-template-columns: minmax(0, 1.3fr) minmax(0, 1fr);
    align-items: start;
  }

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

  .page-about .about-credit__panel {
    grid-template-columns: minmax(0, 0.9fr) minmax(0, 1.4fr);
    align-items: start;
    gap: clamp(2rem, 5vw, 4rem);
  }

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

  .page-about .about-next__panel {
    grid-template-columns: minmax(0, 1.5fr) auto;
    align-items: center;
  }

  .page-about .about-next__links {
    flex-direction: column;
    align-items: stretch;
    min-width: 210px;
  }
}