/* ============ 品牌历程 / page-about ============ */

.page-about {
  --ab-line: rgba(76, 84, 94, .2);
  --ab-line-light: rgba(247, 241, 228, .18);
}

/* ---------- 面包屑 ---------- */

.page-about .ab-crumbs {
  background: var(--ivory);
  padding: 20px 0 0;
}

.page-about .ab-crumbs .crumbs {
  margin: 0;
}

/* ---------- 首屏 ---------- */

.page-about .ab-hero {
  padding-top: 56px;
  padding-bottom: 0;
  background:
    radial-gradient(120% 90% at 84% 12%, rgba(44, 140, 125, .26), transparent 62%),
    radial-gradient(90% 70% at 6% 0%, rgba(231, 180, 76, .16), transparent 58%),
    linear-gradient(178deg, var(--night) 0%, var(--lapis) 100%);
  color: var(--ivory);
  overflow: hidden;
}

.page-about .ab-hero h1 {
  font-size: clamp(34px, 7.4vw, 92px);
  line-height: 1.06;
  letter-spacing: -.015em;
  max-width: 17ch;
  margin: 18px 0 0;
}

.page-about .ab-hero .lede {
  max-width: 46ch;
  margin-top: 24px;
  color: rgba(247, 241, 228, .82);
}

.page-about .ab-hero__facts {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 28px;
  list-style: none;
  margin: 32px 0 0;
  padding: 20px 0 0;
  border-top: 1px solid var(--ab-line-light);
  font-size: 14px;
  color: rgba(247, 241, 228, .72);
}

.page-about .ab-hero__facts .num {
  color: var(--gold);
  font-size: 15px;
}

.page-about .ab-hero__figure {
  margin: 44px 0 0;
}

.page-about .ab-hero__figure .figure__frame {
  border: 1px solid var(--ab-line-light);
  box-shadow: 0 24px 60px -32px rgba(0, 0, 0, .7);
}

.page-about .ab-hero__figure .figure__cap {
  padding: 12px 0 0;
  font-size: 13px;
  color: rgba(247, 241, 228, .55);
}

/* ---------- 矿物色带 ---------- */

.page-about .ab-band {
  height: 8px;
  background: linear-gradient(90deg,
    var(--moss) 0%,
    var(--clay) 34%,
    var(--gold) 68%,
    var(--turq) 100%);
  opacity: .78;
}

/* ---------- 起点 ---------- */

.page-about .ab-origin h2 {
  margin: 14px 0 22px;
}

.page-about .ab-origin .prose p + p {
  margin-top: 18px;
}

/* ---------- 通用标题尺度 ---------- */

.page-about h2.display--lg {
  font-size: clamp(27px, 4.8vw, 54px);
  line-height: 1.14;
  letter-spacing: -.012em;
}

.page-about h3.display--sm {
  font-size: clamp(18px, 2.4vw, 26px);
  line-height: 1.3;
}

/* ---------- 年表 ---------- */

.page-about .ab-chron__head {
  max-width: 62ch;
}

.page-about .ab-chron__head h2 {
  margin: 14px 0 18px;
}

.page-about .ab-chron__figure {
  margin: 48px 0 0;
}

.page-about .ab-chron__figure .figure__frame {
  border: 1px solid var(--ab-line);
}

.page-about .ab-timeline {
  display: grid;
  grid-template-columns: 1fr;
  gap: 26px;
  margin-top: 48px;
}

/* 年份索引 */

.page-about .ab-years ol {
  display: flex;
  gap: 6px;
  list-style: none;
  margin: 0;
  padding: 0 0 6px;
  overflow-x: auto;
  scrollbar-width: none;
  -webkit-overflow-scrolling: touch;
}

.page-about .ab-years ol::-webkit-scrollbar {
  display: none;
}

.page-about .ab-years a {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--stone);
  text-decoration: none;
  white-space: nowrap;
  padding: 7px 12px;
  border: 1px solid var(--ab-line);
  background: var(--ivory);
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.page-about .ab-years a:hover,
.page-about .ab-years a:focus-visible {
  color: var(--lapis);
  border-color: var(--lapis);
}

/* 时间轨道 */

.page-about .ab-track {
  position: relative;
  padding-left: 26px;
}

.page-about .ab-track::before {
  content: "";
  position: absolute;
  left: 7px;
  top: 8px;
  bottom: 8px;
  width: 1px;
  background: linear-gradient(180deg,
    var(--moss) 0%,
    var(--clay) 46%,
    var(--gold) 76%,
    var(--turq) 100%);
  opacity: .62;
}

.page-about .ab-stage {
  position: relative;
  padding-bottom: 40px;
}

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

.page-about .ab-stage::before {
  content: "";
  position: absolute;
  left: -24px;
  top: 9px;
  width: 11px;
  height: 11px;
  border-radius: 50%;
  background: var(--ivory);
  border: 1px solid var(--stone);
  transition: background-color var(--dur) var(--ease),
              border-color var(--dur) var(--ease),
              box-shadow var(--dur) var(--ease);
}

.page-about .ab-stage:target::before {
  background: var(--gold);
  border-color: var(--gold);
  box-shadow: 0 0 0 6px rgba(231, 180, 76, .2);
}

.page-about .ab-stage h3 {
  margin: 0 0 10px;
}

.page-about .ab-stage p {
  margin: 0;
  color: var(--stone);
  line-height: 1.78;
  max-width: 44em;
}

.page-about .ab-stage__year {
  display: inline-block;
  margin-right: 12px;
  color: var(--turq-deep);
  font-size: .62em;
  letter-spacing: .06em;
  vertical-align: .18em;
}

.page-about .ab-stage__more {
  margin-top: 14px;
}

.page-about .ab-stage__more summary {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  cursor: pointer;
  list-style: none;
  padding: 4px 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--lapis);
  transition: color var(--dur) var(--ease);
}

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

.page-about .ab-stage__more summary::after {
  content: "+";
  font-size: 14px;
  line-height: 1;
  color: var(--gold-deep);
  transition: transform var(--dur) var(--ease);
}

.page-about .ab-stage__more[open] summary::after {
  transform: rotate(45deg);
}

.page-about .ab-stage__more summary:hover {
  color: var(--turq-deep);
}

.page-about .ab-stage__more p {
  margin-top: 12px;
  padding-left: 16px;
  border-left: 2px solid var(--gold);
  font-size: 15px;
}

/* ---------- 团队 ---------- */

.page-about .ab-crews {
  display: grid;
  grid-template-columns: 1fr;
  margin-top: 40px;
  border-top: 1px solid var(--ab-line);
}

.page-about .ab-crew {
  padding: 26px 0 30px;
  border-bottom: 1px solid var(--ab-line);
}

.page-about .ab-crew__no {
  font-size: 12px;
  letter-spacing: .14em;
  color: var(--gold-deep);
  margin: 0 0 10px;
}

.page-about .ab-crew h3 {
  position: relative;
  padding-left: 20px;
  margin: 0 0 12px;
}

.page-about .ab-crew h3::before {
  content: "";
  position: absolute;
  left: 0;
  top: .58em;
  width: 9px;
  height: 1px;
  background: var(--gold);
  transition: width var(--dur) var(--ease);
}

.page-about .ab-crew:hover h3::before,
.page-about .ab-crew:focus-within h3::before {
  width: 15px;
}

.page-about .ab-crew p {
  margin: 0;
  color: var(--stone);
  line-height: 1.78;
}

.page-about .ab-crew__detail {
  margin-top: 12px;
  padding-top: 12px;
  border-top: 1px dashed var(--ab-line);
  font-size: 14px;
  color: var(--turq-deep) !important;
}

/* ---------- 沉淀 ---------- */

.page-about .ab-cred {
  background:
    radial-gradient(110% 80% at 88% 0%, rgba(44, 140, 125, .22), transparent 60%),
    linear-gradient(180deg, var(--lapis) 0%, var(--night) 100%);
  color: var(--ivory);
}

.page-about .ab-cred .lede {
  max-width: 46ch;
  margin-top: 18px;
  color: rgba(247, 241, 228, .78);
}

.page-about .ab-cred__list {
  list-style: none;
  margin: 44px 0 0;
  padding: 0;
}

.page-about .ab-cred__item {
  display: grid;
  grid-template-columns: 1fr;
  gap: 10px;
  padding: 26px 0;
  border-top: 1px solid var(--ab-line-light);
}

.page-about .ab-cred__item:last-child {
  border-bottom: 1px solid var(--ab-line-light);
}

.page-about .ab-cred__num {
  font-size: 13px;
  letter-spacing: .16em;
  color: var(--gold);
}

.page-about .ab-cred__title {
  font-size: clamp(18px, 2.3vw, 24px);
  margin: 0 0 10px;
  color: var(--ivory);
}

.page-about .ab-cred__body p {
  margin: 0;
  color: rgba(247, 241, 228, .74);
  line-height: 1.8;
  max-width: 46em;
}

/* ---------- 合作 ---------- */

.page-about .ab-partners h2 {
  margin: 14px 0 18px;
}

.page-about .ab-partners .lede {
  max-width: 52ch;
}

.page-about .ab-partners__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0;
  margin-top: 44px;
  border-top: 1px solid var(--ab-line);
}

.page-about .ab-partner {
  padding: 28px 0 32px;
  border-bottom: 1px solid var(--ab-line);
}

.page-about .ab-partner h3 {
  margin: 0 0 8px;
}

.page-about .ab-partner__stat {
  font-size: 13px;
  letter-spacing: .08em;
  color: var(--turq-deep);
  margin: 0 0 14px;
}

.page-about .ab-partner__stat .num {
  font-size: 22px;
  color: var(--ochre);
  margin-right: 4px;
}

.page-about .ab-partner p:last-child {
  margin: 0;
  color: var(--stone);
  line-height: 1.8;
  max-width: 44em;
}

/* ---------- 地域与支持 ---------- */

.page-about .ab-region__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 40px;
}

.page-about .ab-region h2 {
  margin: 14px 0 22px;
}

.page-about .ab-region .prose p + p {
  margin-top: 16px;
}

.page-about .ab-region__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 30px;
}

.page-about .ab-region__figure {
  margin: 0;
}

.page-about .ab-region__figure .figure__frame {
  border: 1px solid var(--ab-line);
}

/* ---------- 收尾 ---------- */

.page-about .ab-close {
  background: var(--ivory);
}

.page-about .ab-close__inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 18px 28px;
}

.page-about .ab-close__text {
  margin: 0;
  flex: 1 1 260px;
  font-size: 15px;
  color: var(--stone);
}

.page-about .ab-close__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.page-about .ab-totop {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--stone);
  background: none;
  border: 1px solid var(--ab-line);
  padding: 10px 16px;
  cursor: pointer;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.page-about .ab-totop:hover,
.page-about .ab-totop:focus-visible {
  color: var(--lapis);
  border-color: var(--lapis);
}

/* ---------- 图片响应式 ---------- */

.page-about .figure__frame img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
}

/* ---------- 平板及以上 ---------- */

@media (min-width: 760px) {

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

  .page-about .ab-crew {
    padding: 32px 0;
  }

  .page-about .ab-crew:nth-child(odd) {
    border-right: 1px solid var(--ab-line);
    padding-right: 32px;
  }

  .page-about .ab-crew:nth-child(even) {
    padding-left: 32px;
  }

  .page-about .ab-partners__grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 0 48px;
  }

  .page-about .ab-partner {
    border-bottom: 0;
    border-top: 0;
    padding: 32px 0;
  }

  .page-about .ab-cred__item {
    grid-template-columns: 72px minmax(0, 1fr);
    gap: 28px;
    align-items: start;
    padding: 30px 0;
  }
}

/* ---------- 桌面 ---------- */

@media (min-width: 900px) {

  .page-about .ab-timeline {
    grid-template-columns: 124px minmax(0, 1fr);
    gap: 56px;
    margin-top: 72px;
  }

  .page-about .ab-years {
    position: sticky;
    top: 120px;
    align-self: start;
  }

  .page-about .ab-years ol {
    flex-direction: column;
    gap: 0;
    overflow: visible;
    padding: 0;
    border-left: 1px solid var(--ab-line);
  }

  .page-about .ab-years a {
    display: block;
    position: relative;
    border: 0;
    background: none;
    padding: 12px 0 12px 17px;
    font-size: 11px;
  }

  .page-about .ab-years a::before {
    content: "";
    position: absolute;
    left: -4px;
    top: 50%;
    width: 7px;
    height: 7px;
    margin-top: -3.5px;
    border-radius: 50%;
    background: var(--gold);
    transform: scale(0);
    transition: transform var(--dur) var(--ease);
  }

  .page-about .ab-years a:hover::before,
  .page-about .ab-years a:focus-visible::before {
    transform: scale(1);
  }

  .page-about .ab-timeline:has(#stage-2017:target) .ab-years li:nth-child(1) a,
  .page-about .ab-timeline:has(#stage-2019:target) .ab-years li:nth-child(2) a,
  .page-about .ab-timeline:has(#stage-2020:target) .ab-years li:nth-child(3) a,
  .page-about .ab-timeline:has(#stage-2021:target) .ab-years li:nth-child(4) a,
  .page-about .ab-timeline:has(#stage-2023:target) .ab-years li:nth-child(5) a,
  .page-about .ab-timeline:has(#stage-today:target) .ab-years li:nth-child(6) a {
    color: var(--lapis);
    font-weight: 700;
  }

  .page-about .ab-timeline:has(#stage-2017:target) .ab-years li:nth-child(1) a::before,
  .page-about .ab-timeline:has(#stage-2019:target) .ab-years li:nth-child(2) a::before,
  .page-about .ab-timeline:has(#stage-2020:target) .ab-years li:nth-child(3) a::before,
  .page-about .ab-timeline:has(#stage-2021:target) .ab-years li:nth-child(4) a::before,
  .page-about .ab-timeline:has(#stage-2023:target) .ab-years li:nth-child(5) a::before,
  .page-about .ab-timeline:has(#stage-today:target) .ab-years li:nth-child(6) a::before {
    transform: scale(1);
  }

  .page-about .ab-track {
    padding-left: 40px;
  }

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

  .page-about .ab-stage::before {
    left: -37px;
    top: 10px;
  }

  .page-about .ab-stage {
    padding-bottom: 56px;
  }

  .page-about .ab-region__grid {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, .85fr);
    gap: 64px;
    align-items: start;
  }
}

/* ---------- 低动效偏好 ---------- */

@media (prefers-reduced-motion: reduce) {

  .page-about .ab-years a,
  .page-about .ab-years a::before,
  .page-about .ab-stage::before,
  .page-about .ab-stage__more summary::after,
  .page-about .ab-crew h3::before,
  .page-about .ab-totop {
    transition: none !important;
  }
}