/* ===== 品牌历程 page-about ===== */

.page-about {
  --ab-line: var(--edge);
  --ab-quiet: var(--haze);
  display: block;
  padding: 1.25rem 1rem 4.5rem;
  color: var(--ink);
  font-family: var(--font-body);
}

.page-about .ab-crumb {
  margin: 0 0 1.25rem;
}

/* ---------- 首屏 ---------- */

.page-about .ab-hero {
  display: grid;
  gap: 1.75rem;
  padding-bottom: 2.5rem;
  border-bottom: 2px solid var(--ab-line);
}

.page-about .ab-hero .arc-eyebrow {
  margin: 0 0 .7rem;
}

.page-about .ab-hero .arc-h1 {
  margin: 0 0 1rem;
  max-width: 20ch;
}

.page-about .ab-hero .arc-lead {
  margin: 0;
  max-width: 34em;
  color: var(--ink-soft);
}

.page-about .ab-hero__acts {
  display: flex;
  flex-wrap: wrap;
  gap: .75rem;
  margin-top: 1.5rem;
}

.page-about .ab-hero__fig,
.page-about .ab-stages__fig,
.page-about .ab-team__fig {
  margin: 0;
  border: 2px solid var(--ab-line);
  border-radius: 2px;
  background: var(--panel);
  box-shadow: var(--shadow-hard);
  overflow: hidden;
}

.page-about .ab-hero__fig img,
.page-about .ab-stages__fig img,
.page-about .ab-team__fig img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

.page-about .ab-hero__fig img { aspect-ratio: 3 / 2; }
.page-about .ab-stages__fig img { aspect-ratio: 1 / 1; }
.page-about .ab-team__fig img { aspect-ratio: 10 / 7; }

.page-about .ab-hero__fig figcaption,
.page-about .ab-stages__fig figcaption,
.page-about .ab-team__fig figcaption {
  padding: .55rem .85rem;
  font-family: var(--font-mono);
  font-size: .7rem;
  letter-spacing: .06em;
  color: var(--ab-quiet);
  border-top: 2px solid var(--ab-line);
}

/* ---------- 轨道 + 内容骨架 ---------- */

.page-about .ab-layout {
  display: grid;
  gap: 2rem;
  padding-top: 2.25rem;
}

.page-about .ab-rail {
  position: sticky;
  top: 0;
  z-index: 6;
  margin-inline: -1rem;
  padding: .7rem 1rem .55rem;
  background: rgba(11, 10, 18, .95);
  border-bottom: 2px solid var(--ab-line);
  backdrop-filter: blur(8px);
}

.page-about .ab-rail__title {
  position: absolute;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  overflow: hidden;
  clip-path: inset(50%);
  white-space: nowrap;
  border: 0;
}

.page-about .ab-rail__list {
  display: flex;
  gap: .45rem;
  margin: 0;
  padding: 0 0 .2rem;
  list-style: none;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

.page-about .ab-rail__link {
  display: inline-flex;
  align-items: center;
  gap: .45rem;
  padding: .35rem .65rem;
  border: 2px solid var(--ab-line);
  border-radius: 2px;
  color: var(--ink-soft);
  font-size: .78rem;
  line-height: 1.3;
  text-decoration: none;
  white-space: nowrap;
  transition: color .16s var(--ease), border-color .16s var(--ease), background-color .16s var(--ease);
}

.page-about .ab-rail__dot {
  flex: none;
  width: .45rem;
  height: .45rem;
  border-radius: 50%;
  background: var(--ab-line);
  transition: background-color .16s var(--ease), box-shadow .16s var(--ease);
}

.page-about .ab-rail__link:hover,
.page-about .ab-rail__link:focus-visible {
  color: var(--ink);
  border-color: var(--volt);
}

.page-about .ab-rail__link[aria-current="true"] {
  color: var(--ink);
  border-color: var(--neon);
  background: rgba(168, 85, 247, .14);
}

.page-about .ab-rail__link[aria-current="true"] .ab-rail__dot {
  background: var(--mint);
  box-shadow: 0 0 8px var(--mint);
}

/* ---------- 通用区块 ---------- */

.page-about .ab-sec {
  margin-top: 2rem;
  padding-top: 2rem;
  border-top: 2px solid var(--ab-line);
}

.page-about .ab-main > .ab-sec:first-child {
  margin-top: 0;
  padding-top: 0;
  border-top: 0;
}

.page-about .ab-sec .arc-eyebrow {
  margin: 0 0 .5rem;
}

.page-about .ab-sec .arc-h2 {
  margin: 0 0 .9rem;
}

.page-about .ab-sec .arc-prose {
  max-width: 36em;
}

/* ---------- 四件事 ---------- */

.page-about .ab-quad {
  display: grid;
  gap: .9rem;
  margin-top: 1.5rem;
}

.page-about .ab-quad__item {
  padding: 1.1rem;
  border: 2px solid var(--ab-line);
  border-radius: 2px;
  background: var(--panel);
  transition: border-color .16s var(--ease);
}

.page-about .ab-quad__item:hover {
  border-color: var(--neon);
}

.page-about .ab-quad__item .arc-h3 {
  margin: 0 0 .5rem;
}

.page-about .ab-quad__item p {
  margin: 0;
  font-size: .88rem;
  line-height: 1.75;
  color: var(--ab-quiet);
}

/* ---------- 阶段演进 ---------- */

.page-about .ab-stages__head {
  display: grid;
  gap: 1.5rem;
  align-items: start;
}

.page-about .ab-stage-list {
  display: grid;
  gap: 1rem;
  margin-top: 1.75rem;
}

.page-about .ab-stage {
  border: 2px solid var(--ab-line);
  border-radius: 2px;
  background: var(--panel);
  box-shadow: var(--shadow-hard);
  transition: border-color .18s var(--ease);
}

.page-about .ab-stage:nth-child(even) {
  outline: 1px solid rgba(74, 63, 115, .85);
  outline-offset: 3px;
}

.page-about .ab-stage:hover,
.page-about .ab-stage[open] {
  border-color: var(--neon);
}

.page-about .ab-stage__sum {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto auto;
  align-items: center;
  gap: .8rem;
  padding: .95rem 1rem;
  list-style: none;
  cursor: pointer;
  -webkit-tap-highlight-color: transparent;
}

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

.page-about .ab-stage__sum:focus-visible {
  outline: 2px solid var(--mint);
  outline-offset: -2px;
}

.page-about .ab-stage__idx {
  font-family: var(--font-mono);
  font-size: .7rem;
  letter-spacing: .08em;
  color: var(--volt);
  white-space: nowrap;
}

.page-about .ab-stage__name {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 1.05rem;
  color: var(--ink);
  min-width: 0;
}

.page-about .ab-stage__metric {
  display: flex;
  align-items: baseline;
  gap: .25rem;
}

.page-about .ab-stage__num {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 1.6rem;
  line-height: 1;
  color: var(--amber);
}

.page-about .ab-stage__unit {
  font-size: .68rem;
  color: var(--ab-quiet);
}

.page-about .ab-stage__arrow {
  width: .5rem;
  height: .5rem;
  border-right: 2px solid var(--volt);
  border-bottom: 2px solid var(--volt);
  transform: rotate(45deg);
  transition: transform .18s var(--ease), border-color .18s var(--ease);
}

.page-about .ab-stage[open] .ab-stage__arrow {
  transform: rotate(-135deg);
  border-color: var(--mint);
}

.page-about .ab-stage__body {
  margin-top: .2rem;
  padding: 1rem 1rem 1.2rem;
  border-top: 2px solid var(--ab-line);
}

.page-about .ab-stage__body p {
  margin: 0 0 .9rem;
  max-width: 40em;
  font-size: .9rem;
  line-height: 1.78;
  color: var(--ink-soft);
}

.page-about .ab-stage__list {
  display: grid;
  gap: .5rem;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .ab-stage__list li {
  position: relative;
  padding-left: 1.1rem;
  font-size: .84rem;
  line-height: 1.65;
  color: var(--ab-quiet);
}

.page-about .ab-stage__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: .6em;
  width: .5rem;
  height: 2px;
  background: var(--mint);
}

/* ---------- 场馆网络 ---------- */

.page-about .ab-stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(7rem, 1fr));
  gap: .7rem;
  margin: 1.5rem 0 0;
  padding: 0;
  list-style: none;
}

.page-about .ab-stats li {
  padding: .85rem .9rem;
  border: 2px solid var(--ab-line);
  border-radius: 2px;
  background: var(--panel);
}

.page-about .ab-stats .ab-num {
  display: block;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 1.85rem;
  line-height: 1.05;
  color: var(--gold);
}

.page-about .ab-stats small {
  display: block;
  margin-top: .35rem;
  font-size: .73rem;
  color: var(--ab-quiet);
}

.page-about .ab-tiers {
  display: grid;
  gap: .85rem;
  margin-top: 1.25rem;
}

.page-about .ab-tier {
  display: grid;
  gap: .35rem;
  padding: 1rem 1.1rem;
  border-radius: 2px;
  border-left: 6px solid var(--neon);
  background: linear-gradient(90deg, rgba(168, 85, 247, .14), rgba(23, 19, 41, .96) 68%);
}

.page-about .ab-tier:nth-child(2) {
  border-left-color: var(--volt);
  background: linear-gradient(90deg, rgba(47, 210, 255, .14), rgba(23, 19, 41, .96) 68%);
}

.page-about .ab-tier:nth-child(3) {
  border-left-color: var(--mint);
  background: linear-gradient(90deg, rgba(53, 224, 161, .14), rgba(23, 19, 41, .96) 68%);
}

.page-about .ab-tier__name {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 1rem;
  color: var(--ink);
}

.page-about .ab-tier__desc {
  margin: 0;
  font-size: .86rem;
  line-height: 1.72;
  color: var(--ab-quiet);
}

/* ---------- 团队 ---------- */

.page-about .ab-team {
  display: grid;
  gap: 1.5rem;
  margin-top: 1.5rem;
}

.page-about .ab-team__blocks {
  display: grid;
  gap: .85rem;
}

.page-about .ab-team__blk {
  padding: 1rem 1.1rem 1.15rem;
  border: 2px solid var(--ab-line);
  border-radius: 2px;
  background: var(--panel);
  transition: border-color .16s var(--ease);
}

.page-about .ab-team__blk:hover {
  border-color: var(--neon);
}

.page-about .ab-team__blk:nth-child(1) { border-top: 6px solid var(--neon); }
.page-about .ab-team__blk:nth-child(2) { border-top: 6px solid var(--volt); }
.page-about .ab-team__blk:nth-child(3) { border-top: 6px solid var(--mint); }

.page-about .ab-team__num {
  margin: 0 0 .5rem;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: .95rem;
  letter-spacing: .02em;
  color: var(--gold);
}

.page-about .ab-team__blk .arc-h3 {
  margin: 0 0 .45rem;
}

.page-about .ab-team__blk p {
  margin: 0;
  font-size: .85rem;
  line-height: 1.7;
  color: var(--ab-quiet);
}

.page-about .ab-team__blk .ab-team__num {
  font-size: .95rem;
  color: var(--gold);
}

/* ---------- 合作生态 ---------- */

.page-about .ab-eco {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: .7rem;
  margin: 1.5rem 0 0;
  padding: 0;
  list-style: none;
}

.page-about .ab-eco li {
  padding: .85rem .9rem;
  border: 2px solid var(--ab-line);
  border-radius: 2px;
  background: var(--panel);
  font-size: .82rem;
  line-height: 1.55;
  color: var(--ink-soft);
  transition: border-color .16s var(--ease), color .16s var(--ease);
}

.page-about .ab-eco li:hover {
  border-color: var(--volt);
  color: var(--ink);
}

.page-about .ab-eco__k {
  display: block;
  margin-bottom: .3rem;
  font-family: var(--font-mono);
  font-size: .66rem;
  letter-spacing: .1em;
  color: var(--ab-quiet);
}

/* ---------- 选择理由 ---------- */

.page-about .ab-why__list {
  display: grid;
  gap: .9rem;
  margin: 1.5rem 0 0;
  padding: 0;
  list-style: none;
  counter-reset: ab-why;
}

.page-about .ab-why__item {
  counter-increment: ab-why;
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 1rem;
  align-items: start;
  padding: 1.1rem;
  border: 2px solid var(--ab-line);
  border-radius: 2px;
  background: var(--panel);
}

.page-about .ab-why__item::before {
  content: "0" counter(ab-why);
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 1.2rem;
  line-height: 1;
  color: var(--neon);
}

.page-about .ab-why__item .arc-h3 {
  margin: 0 0 .4rem;
}

.page-about .ab-why__item p {
  margin: 0;
  font-size: .88rem;
  line-height: 1.72;
  color: var(--ab-quiet);
}

.page-about .ab-cta {
  margin-top: 1.75rem;
  padding: 1.4rem 1.2rem;
  border: 2px solid var(--neon);
  border-radius: 2px;
  background: linear-gradient(135deg, rgba(168, 85, 247, .18), rgba(11, 10, 18, .92) 62%);
  box-shadow: var(--shadow-hard);
}

.page-about .ab-cta p {
  margin: 0 0 1rem;
  max-width: 34em;
  font-size: .92rem;
  line-height: 1.75;
  color: var(--ink-soft);
}

.page-about .ab-cta__acts {
  display: flex;
  flex-wrap: wrap;
  gap: .75rem;
}

/* ---------- 断点 ---------- */

@media (min-width: 48rem) {
  .page-about .ab-quad {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

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

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

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

@media (min-width: 62rem) {
  .page-about {
    padding: 2.5rem 2.5rem 6rem;
  }

  .page-about .ab-hero {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, .95fr);
    gap: 3rem;
    align-items: center;
  }

  .page-about .ab-layout {
    grid-template-columns: var(--rail-w) minmax(0, 1fr);
    gap: 3.5rem;
    align-items: start;
  }

  .page-about .ab-rail {
    position: sticky;
    top: calc(var(--header-h) + 1.5rem);
    z-index: 2;
    margin: 0;
    padding: 0 0 0 1.1rem;
    border: 0;
    border-left: 2px solid var(--ab-line);
    background: none;
    backdrop-filter: none;
  }

  .page-about .ab-rail__title {
    position: static;
    width: auto;
    height: auto;
    margin: 0 0 .9rem;
    padding: 0;
    overflow: visible;
    clip-path: none;
    font-family: var(--font-mono);
    font-size: .68rem;
    letter-spacing: .16em;
    color: var(--ab-quiet);
  }

  .page-about .ab-rail__list {
    flex-direction: column;
    gap: 0;
    padding: 0;
    overflow: visible;
  }

  .page-about .ab-rail__link {
    display: block;
    margin-left: -1.1rem;
    padding: .45rem .4rem .45rem 1.1rem;
    border: 0;
    border-left: 3px solid transparent;
    border-radius: 0;
    background: none;
    font-size: .85rem;
    line-height: 1.45;
    white-space: normal;
  }

  .page-about .ab-rail__link:hover,
  .page-about .ab-rail__link:focus-visible,
  .page-about .ab-rail__link[aria-current="true"] {
    border-left-color: var(--neon);
    background: linear-gradient(90deg, rgba(168, 85, 247, .2), rgba(168, 85, 247, 0) 88%);
    color: var(--ink);
  }

  .page-about .ab-rail__dot {
    display: none;
  }

  .page-about .ab-stages__head {
    grid-template-columns: minmax(0, 1fr) 16rem;
    gap: 2.5rem;
    align-items: center;
  }

  .page-about .ab-team {
    grid-template-columns: minmax(0, 1.2fr) minmax(0, .8fr);
    gap: 2.5rem;
    align-items: start;
  }

  .page-about .ab-stage__sum {
    grid-template-columns: 5.5rem minmax(0, 1fr) auto auto;
    gap: 1.2rem;
    padding: 1.05rem 1.25rem;
  }

  .page-about .ab-stage__num {
    font-size: 2rem;
  }

  .page-about .ab-stage__body {
    padding: 1.1rem 1.25rem 1.35rem;
  }

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

  .page-about .ab-cta {
    padding: 1.75rem 1.6rem;
  }
}