.page-about {
  --tl-col: 44px;
  --tl-gap: 14px;
  position: relative;
  background:
    radial-gradient(90% 46% at 100% 0%, rgba(187, 215, 230, .55), rgba(187, 215, 230, 0) 62%),
    var(--paper);
  color: var(--ink);
  overflow-x: clip;
  padding-bottom: 8px;
}

/* ---------- 面包屑 ---------- */
.page-about .breadcrumb {
  padding: 20px 0 4px;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  isolation: isolate;
  padding: 20px 0 56px;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  z-index: -1;
  top: 0;
  left: 0;
  right: 0;
  height: 82%;
  background: linear-gradient(118deg, rgba(158, 43, 43, .16) 0 40%, rgba(22, 50, 79, .12) 40% 100%);
  clip-path: polygon(0 0, 100% 0, 100% 68%, 0 100%);
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  z-index: -1;
  top: 16px;
  right: 0;
  width: min(48%, 460px);
  height: 168px;
  background: linear-gradient(158deg, var(--sky) 0%, rgba(240, 192, 112, .7) 100%);
  border: var(--edge) solid var(--indigo);
  box-shadow: var(--shadow-indigo);
  clip-path: polygon(0 0, 100% 0, 100% 100%, 22% 100%);
  opacity: .62;
}

.page-about .about-hero-grid {
  position: relative;
  display: grid;
  grid-template-columns: 1fr;
  gap: 32px;
}

.page-about h1 {
  font-family: var(--font-head);
  font-weight: 700;
  font-size: clamp(2.2rem, 5.6vw, 4.1rem);
  line-height: 1.14;
  letter-spacing: -.01em;
  margin: 14px 0 20px;
  color: var(--ink);
  text-wrap: balance;
}

.page-about .about-lede {
  max-width: 46ch;
  margin: 0 0 26px;
  font-size: 1.06rem;
  line-height: 1.85;
  color: var(--indigo);
}

.page-about .about-hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.page-about .about-hero-actions .btn {
  text-decoration: none;
}

.page-about .about-hero-aside {
  align-self: start;
  background: var(--card);
  border: var(--edge) solid var(--ink);
  box-shadow: var(--shadow-hard);
  padding: 22px 22px 20px;
}

.page-about .aside-kicker {
  margin: 0;
  font-family: var(--font-num);
  font-size: .78rem;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--stone);
}

.page-about .aside-big {
  margin: 6px 0 0;
  font-family: var(--font-num);
  font-size: clamp(2.8rem, 8vw, 4rem);
  line-height: 1;
  color: var(--red);
  letter-spacing: -.02em;
}

.page-about .aside-big span {
  font-size: .42em;
  margin-left: 4px;
  color: var(--indigo);
}

.page-about .aside-cap {
  margin: 6px 0 14px;
  font-size: .92rem;
  color: var(--indigo);
}

.page-about .about-hero-aside .note {
  margin: 0;
  padding-top: 12px;
  border-top: 2px dashed rgba(110, 106, 99, .45);
}

/* ---------- 主体两栏 ---------- */
.page-about .about-body {
  display: grid;
  grid-template-columns: 1fr;
  gap: 26px;
  padding-bottom: 64px;
}

/* ---------- 锚点索引 ---------- */
.page-about .anchor-index {
  background: rgba(255, 252, 245, .8);
  border: 2px solid var(--indigo);
  box-shadow: var(--shadow-indigo);
  padding: 14px 14px 12px;
}

.page-about .anchor-index-title {
  margin: 0 0 10px;
  font-family: var(--font-num);
  font-size: .76rem;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--stone);
}

.page-about .anchor-index-list {
  display: flex;
  gap: 8px;
  list-style: none;
  margin: 0;
  padding: 0 0 4px;
  overflow-x: auto;
  scrollbar-width: thin;
}

.page-about .anchor-index-list li {
  flex: 0 0 auto;
}

.page-about .anchor-link {
  display: inline-block;
  padding: 7px 12px;
  border: 2px solid var(--indigo);
  background: var(--card);
  color: var(--indigo);
  font-size: .86rem;
  line-height: 1.2;
  text-decoration: none;
  white-space: nowrap;
  transition: background .18s ease, color .18s ease, border-color .18s ease;
}

.page-about .anchor-link:hover,
.page-about .anchor-link:focus-visible {
  background: var(--butter);
  border-color: var(--gold);
}

.page-about .anchor-link[aria-current="true"] {
  background: var(--red);
  border-color: var(--red-deep);
  color: var(--paper);
}

/* ---------- 时间轴 ---------- */
.page-about .about-stream {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 30px;
}

.page-about .about-stream::before {
  content: "";
  position: absolute;
  top: 10px;
  bottom: 10px;
  left: calc(var(--tl-col) / 2 - 1px);
  width: 2px;
  background: linear-gradient(180deg, var(--red) 0%, var(--gold) 48%, var(--sky) 100%);
  opacity: .8;
}

.page-about .tl-item {
  position: relative;
  display: grid;
  grid-template-columns: var(--tl-col) minmax(0, 1fr);
  gap: var(--tl-gap);
}

.page-about .tl-axis {
  padding-top: 4px;
}

.page-about .tl-num {
  display: grid;
  place-items: center;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--red);
  color: var(--paper);
  border: var(--edge) solid var(--ink);
  box-shadow: var(--shadow-indigo);
  font-family: var(--font-num);
  font-size: 1rem;
  letter-spacing: .04em;
}

.page-about .tl-card {
  background: var(--card);
  border: var(--edge) solid var(--ink);
  box-shadow: var(--shadow-hard);
  padding: 20px 18px 22px;
  transition: box-shadow .22s ease, border-color .22s ease;
}

.page-about .tl-card:hover {
  box-shadow: var(--shadow-mid);
  border-color: var(--gold);
}

.page-about .tl-meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  margin: 0 0 10px;
}

.page-about .tl-era {
  font-size: .84rem;
  color: var(--stone);
}

.page-about .tl-title {
  margin: 0 0 14px;
  font-family: var(--font-head);
  font-weight: 700;
  font-size: clamp(1.3rem, 3.2vw, 1.85rem);
  line-height: 1.34;
  color: var(--indigo);
}

.page-about .accordion-trigger {
  display: flex;
  align-items: baseline;
  gap: 10px;
  width: 100%;
  margin: 0;
  padding: 0;
  border: 0;
  background: none;
  font: inherit;
  color: inherit;
  text-align: left;
  cursor: pointer;
}

.page-about .accordion-trigger::after {
  content: "▾";
  margin-left: auto;
  font-size: .8rem;
  color: var(--gold);
  transition: transform .2s ease;
}

.page-about .accordion-item[data-open] .accordion-trigger::after {
  transform: rotate(180deg);
}

.page-about .accordion-panel > p {
  margin: 0 0 14px;
  font-size: 1rem;
  line-height: 1.85;
  color: var(--ink);
}

.page-about .accordion-panel > p:last-child {
  margin-bottom: 0;
}

/* ---------- 三次改版列表 ---------- */
.page-about .phase-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 16px;
  counter-reset: phase;
}

.page-about .phase-item {
  padding-left: 16px;
  border-left: 3px solid var(--sky);
}

.page-about .phase-index {
  display: inline-block;
  margin-bottom: 6px;
  font-family: var(--font-num);
  font-size: .76rem;
  letter-spacing: .16em;
  color: var(--red);
}

.page-about .phase-item h3 {
  margin: 0 0 6px;
  font-family: var(--font-head);
  font-size: 1.12rem;
  line-height: 1.45;
  color: var(--ink);
}

.page-about .phase-item p {
  margin: 0;
  font-size: .98rem;
  line-height: 1.8;
  color: var(--stone);
}

/* ---------- 团队双栏 ---------- */
.page-about .tl-cols {
  display: grid;
  grid-template-columns: 1fr;
  gap: 20px;
}

/* ---------- 规矩清单 ---------- */
.page-about .rule-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.page-about .rule-item {
  position: relative;
  padding: 12px 14px 12px 38px;
  background: rgba(240, 192, 112, .28);
  border-left: 3px solid var(--gold);
  font-size: .98rem;
  line-height: 1.8;
  color: var(--indigo);
}

.page-about .rule-item::before {
  content: "◆";
  position: absolute;
  left: 14px;
  top: 12px;
  color: var(--red);
  font-size: .72rem;
}

.page-about .rule-item strong {
  color: var(--ink);
  font-weight: 500;
}

/* ---------- 图片占位 ---------- */
.page-about .figure {
  margin: 16px 0 4px;
}

.page-about .figure-img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  border: var(--edge) solid var(--ink);
  box-shadow: var(--shadow-indigo);
  background: linear-gradient(140deg, var(--sky), rgba(240, 192, 112, .8));
}

.page-about .figure--square .figure-img {
  aspect-ratio: 1 / 1;
}

.page-about .figure-cap {
  margin: 10px 0 0;
  font-size: .84rem;
  line-height: 1.7;
  color: var(--stone);
}

.page-about .figure--banner {
  margin: 4px 0;
}

.page-about .figure--banner .figure-img {
  aspect-ratio: 16 / 7;
}

/* ---------- 数字块 ---------- */
.page-about .about-stats {
  position: relative;
  background: linear-gradient(150deg, var(--indigo) 0%, #0d1f33 100%);
  border: var(--edge) solid var(--ink);
  box-shadow: var(--shadow-hard);
  padding: 26px 20px 28px;
  color: var(--paper);
}

.page-about .about-stats .eyebrow {
  color: var(--butter);
}

.page-about .about-stats h2 {
  margin: 6px 0 0;
  font-family: var(--font-head);
  font-weight: 700;
  font-size: clamp(1.5rem, 3.4vw, 2.2rem);
  line-height: 1.3;
  color: var(--paper);
}

.page-about .stat-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin-top: 22px;
  background: rgba(247, 241, 230, .22);
  border: 1px solid rgba(247, 241, 230, .22);
}

.page-about .stat-block {
  background: var(--indigo);
  padding: 16px 14px 18px;
}

.page-about .stat-num {
  display: block;
  font-family: var(--font-num);
  font-size: clamp(2.1rem, 6.4vw, 3.2rem);
  line-height: 1;
  letter-spacing: -.02em;
  color: var(--butter);
}

.page-about .stat-unit {
  font-size: .34em;
  margin-left: 3px;
  color: var(--sky);
  letter-spacing: 0;
}

.page-about .stat-label {
  margin: 8px 0 0;
  font-size: .88rem;
  line-height: 1.6;
  color: rgba(247, 241, 230, .8);
}

/* ---------- 下一步 ---------- */
.page-about .about-next {
  padding: 8px 0 56px;
}

.page-about .about-next h2 {
  margin: 0 0 20px;
  font-family: var(--font-head);
  font-weight: 700;
  font-size: clamp(1.5rem, 3.4vw, 2.1rem);
  color: var(--indigo);
}

.page-about .about-next-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
}

.page-about .next-card {
  position: relative;
  display: block;
  padding: 20px 18px 18px;
  background: var(--card);
  border: var(--edge) solid var(--ink);
  box-shadow: var(--shadow-hard);
  color: var(--ink);
  text-decoration: none;
  transition: box-shadow .22s ease, border-color .22s ease, transform .22s ease;
}

.page-about .next-card:hover,
.page-about .next-card:focus-visible {
  box-shadow: var(--shadow-mid);
  border-color: var(--gold);
  transform: translateY(-3px);
}

.page-about .next-num {
  display: block;
  font-family: var(--font-num);
  font-size: 1.6rem;
  line-height: 1;
  color: var(--red);
  margin-bottom: 10px;
}

.page-about .next-card h3 {
  margin: 0 0 8px;
  font-family: var(--font-head);
  font-size: 1.14rem;
  color: var(--indigo);
}

.page-about .next-card p {
  margin: 0 0 14px;
  font-size: .94rem;
  line-height: 1.78;
  color: var(--stone);
}

.page-about .next-go {
  display: inline-block;
  padding: 5px 12px;
  border: 2px solid var(--indigo);
  font-size: .84rem;
  color: var(--indigo);
  transition: background .18s ease, color .18s ease;
}

.page-about .next-card:hover .next-go {
  background: var(--butter);
}

/* ---------- 响应式 ---------- */
@media (min-width: 700px) {
  .page-about .about-hero {
    padding: 32px 0 72px;
  }

  .page-about .about-hero::after {
    height: 220px;
  }

  .page-about .about-body {
    gap: 34px;
  }

  .page-about .tl-card {
    padding: 26px 26px 28px;
  }

  .page-about .tl-item:nth-child(even) .tl-card {
    margin-left: 24px;
  }

  .page-about .tl-item:nth-child(3n) .tl-card {
    margin-left: 12px;
  }

  .page-about .tl-cols {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, .85fr);
    gap: 24px;
    align-items: start;
  }

  .page-about .tl-cols .figure {
    margin-top: 0;
  }

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

  .page-about .about-next-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 20px;
  }

  .page-about .about-next-grid .next-card:nth-child(2) {
    margin-top: 20px;
  }
}

@media (min-width: 1000px) {
  .page-about .about-hero-grid {
    grid-template-columns: 7fr 5fr;
    gap: 52px;
    align-items: center;
  }

  .page-about .about-hero-aside {
    margin-top: -8px;
  }

  .page-about .about-body {
    grid-template-columns: 186px minmax(0, 1fr);
    gap: 52px;
    align-items: start;
  }

  .page-about .about-rail {
    position: sticky;
    top: 92px;
  }

  .page-about .anchor-index-list {
    flex-direction: column;
    gap: 2px;
    padding: 0;
    overflow: visible;
  }

  .page-about .anchor-index-list li {
    flex: 1 1 auto;
  }

  .page-about .anchor-link {
    display: block;
    width: 100%;
    padding: 7px 0 7px 14px;
    border: 0;
    border-left: 3px solid rgba(110, 106, 99, .35);
    background: transparent;
    white-space: normal;
    font-size: .92rem;
  }

  .page-about .anchor-link:hover,
  .page-about .anchor-link:focus-visible {
    background: rgba(240, 192, 112, .3);
    border-left-color: var(--gold);
  }

  .page-about .anchor-link[aria-current="true"] {
    background: transparent;
    border-left-color: var(--red);
    color: var(--red);
    font-weight: 500;
  }

  .page-about .about-stats {
    padding: 34px 30px 36px;
  }

  .page-about .stat-grid {
    grid-template-columns: repeat(6, minmax(0, 1fr));
  }
}

@media (max-width: 699px) {
  .page-about .about-stream::before {
    left: 19px;
  }

  .page-about .accordion-item:not([data-open]) .accordion-panel {
    display: none;
  }

  .page-about .about-hero::after {
    opacity: .4;
    height: 120px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .tl-card,
  .page-about .next-card,
  .page-about .anchor-link,
  .page-about .accordion-trigger::after {
    transition: none;
  }

  .page-about .next-card:hover,
  .page-about .next-card:focus-visible {
    transform: none;
  }
}