.page-about {
  --ab-hair: 1px solid rgba(240, 217, 166, 0.16);
  --ab-hair-soft: 1px solid rgba(240, 217, 166, 0.09);
  --ab-stack: clamp(18px, 3vw, 36px);
  --ab-sec-pad: clamp(32px, 4.6vw, 64px);
  background: var(--cg-ink-950);
  color: var(--cg-paper);
  font-family: var(--cg-font-body);
  overflow-x: clip;
}

.page-about img {
  max-width: 100%;
  height: auto;
}

.page-about a:focus-visible,
.page-about [tabindex="-1"]:focus-visible {
  outline: 2px solid var(--cg-gold-500);
  outline-offset: 3px;
}

/* ---------- 首屏 ---------- */
.page-about .ab-hero {
  position: relative;
  padding-top: clamp(20px, 3vw, 34px);
  padding-bottom: clamp(32px, 5vw, 60px);
  background:
    radial-gradient(circle at 84% 10%, rgba(214, 168, 75, 0.12), transparent 56%),
    radial-gradient(circle at 6% 88%, rgba(27, 74, 58, 0.55), transparent 58%),
    var(--cg-ink-950);
  overflow: hidden;
}

.page-about .ab-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(to right, rgba(240, 217, 166, 0.055) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(240, 217, 166, 0.055) 1px, transparent 1px);
  background-size: 56px 56px;
  mask-image: linear-gradient(to bottom, rgba(0, 0, 0, 0.9), transparent 88%);
  -webkit-mask-image: linear-gradient(to bottom, rgba(0, 0, 0, 0.9), transparent 88%);
}

.page-about .ab-hero__grid {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(24px, 4vw, 46px);
  align-items: end;
}

.page-about .ab-hero__title {
  margin: 16px 0 0;
  font-family: var(--cg-font-display);
  font-weight: 800;
  font-size: clamp(38px, 7.4vw, 82px);
  line-height: 1.02;
  letter-spacing: -0.03em;
  color: var(--cg-paper);
  text-wrap: balance;
}

.page-about .ab-hero__mark {
  display: block;
  color: var(--cg-gold-500);
}

.page-about .ab-hero__lede {
  margin: 20px 0 0;
  max-width: 50ch;
  font-size: clamp(15px, 1.5vw, 18px);
  line-height: 1.8;
  color: rgba(246, 241, 231, 0.84);
}

.page-about .ab-hero__lede--sub {
  margin-top: 12px;
  font-size: clamp(14px, 1.3vw, 16px);
  color: rgba(246, 241, 231, 0.62);
}

.page-about .ab-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 26px;
}

.page-about .ab-hero__fig {
  position: relative;
  margin: 0;
}

.page-about .ab-hero__fig img {
  display: block;
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  border: 1px solid rgba(214, 168, 75, 0.28);
  border-radius: var(--cg-radius);
  filter: saturate(0.82) contrast(1.05);
}

.page-about .ab-hero__fig::after {
  content: "";
  position: absolute;
  top: 0;
  right: 0;
  width: 62px;
  height: 62px;
  border-top: 1px solid var(--cg-gold-500);
  border-right: 1px solid var(--cg-gold-500);
  opacity: 0.75;
  pointer-events: none;
}

.page-about .ab-hero__cap {
  margin-top: 10px;
  font-family: var(--cg-font-mono);
  font-size: 11px;
  letter-spacing: 0.05em;
  color: var(--cg-blue-400);
}

.page-about .ab-stats {
  position: relative;
  z-index: 1;
  list-style: none;
  margin: clamp(28px, 4vw, 46px) auto 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: rgba(240, 217, 166, 0.18);
  border: 1px solid rgba(240, 217, 166, 0.18);
  border-radius: var(--cg-radius);
  overflow: hidden;
}

.page-about .ab-stats li {
  background: var(--cg-ink-950);
  padding: 16px 14px 18px;
}

.page-about .ab-stats__num {
  display: block;
  font-family: var(--cg-font-mono);
  font-size: clamp(22px, 3vw, 34px);
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--cg-gold-500);
}

.page-about .ab-stats__label {
  display: block;
  margin-top: 8px;
  font-size: 12.5px;
  line-height: 1.6;
  color: rgba(246, 241, 231, 0.68);
}

/* ---------- 布局骨架 ---------- */
.page-about .ab-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--ab-stack);
  padding-top: clamp(28px, 4vw, 56px);
  padding-bottom: clamp(40px, 6vw, 84px);
}

/* ---------- 左侧索引 ---------- */
.page-about .ab-rail {
  padding-block: 10px;
  border-top: var(--ab-hair);
  border-bottom: var(--ab-hair);
  overflow-x: auto;
  overscroll-behavior-x: contain;
}

.page-about .ab-rail__title {
  margin: 0 0 8px;
  font-family: var(--cg-font-mono);
  font-size: 10.5px;
  letter-spacing: 0.22em;
  color: var(--cg-blue-400);
}

.page-about .ab-rail__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  gap: 6px;
}

.page-about .ab-rail__link {
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
  padding: 7px 10px;
  font-size: 13px;
  white-space: nowrap;
  text-decoration: none;
  color: rgba(246, 241, 231, 0.74);
  border: 1px solid transparent;
  border-radius: var(--cg-radius);
  transition: color var(--cg-dur) var(--cg-ease), border-color var(--cg-dur) var(--cg-ease);
}

.page-about .ab-rail__link:hover,
.page-about .ab-rail__link:focus-visible {
  color: var(--cg-gold-200);
  border-color: rgba(214, 168, 75, 0.48);
}

.page-about .ab-rail__idx {
  font-family: var(--cg-font-mono);
  font-size: 10.5px;
  letter-spacing: 0.1em;
  color: var(--cg-gold-500);
}

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

/* ---------- 章节通用 ---------- */
.page-about .ab-sec {
  padding-block: var(--ab-sec-pad);
  border-top: var(--ab-hair-soft);
}

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

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

.page-about .ab-sec__title {
  margin: 12px 0 0;
  font-family: var(--cg-font-display);
  font-weight: 700;
  font-size: clamp(26px, 4vw, 44px);
  line-height: 1.14;
  letter-spacing: -0.02em;
  color: var(--cg-paper);
  text-wrap: balance;
}

.page-about .ab-sec__lead {
  margin: 14px 0 0;
  font-size: clamp(15px, 1.6vw, 17.5px);
  line-height: 1.8;
  color: rgba(246, 241, 231, 0.82);
}

.page-about .ab-sec__text {
  margin: 14px 0 0;
  max-width: 66ch;
  font-size: 15px;
  line-height: 1.85;
  color: rgba(246, 241, 231, 0.7);
}

.page-about .ab-inline {
  color: var(--cg-gold-200);
  text-decoration: none;
  border-bottom: 1px solid rgba(214, 168, 75, 0.55);
}

.page-about .ab-inline:hover,
.page-about .ab-inline:focus-visible {
  color: var(--cg-gold-500);
}

/* ---------- 术语注释 ---------- */
.page-about .ab-note {
  margin: clamp(22px, 3vw, 32px) 0 0;
  padding: clamp(16px, 2.4vw, 22px);
  max-width: 46ch;
  backdrop-filter: blur(6px);
}

.page-about .ab-note__title {
  margin: 0;
  font-family: var(--cg-font-mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--cg-gold-500);
}

.page-about .ab-note__body {
  margin: 10px 0 0;
  font-size: 14px;
  line-height: 1.8;
  color: rgba(246, 241, 231, 0.78);
}

/* ---------- 纸面板块：栏目体系 ---------- */
.page-about .ab-sec--paper {
  margin-block: clamp(6px, 1vw, 14px);
  padding-inline: clamp(18px, 3.2vw, 40px);
  background: var(--cg-paper);
  color: var(--cg-slate);
  border-top: 0;
  border-radius: var(--cg-radius);
  box-shadow: 0 24px 60px -42px rgba(0, 0, 0, 0.85);
}

.page-about .ab-sec--paper .ab-sec__title {
  color: var(--cg-ink-950);
}

.page-about .ab-sec--paper .ab-sec__lead {
  color: rgba(43, 54, 53, 0.86);
}

.page-about .ab-sec--paper .cg-eyebrow {
  color: var(--cg-ink-600);
}

.page-about .ab-cat {
  list-style: none;
  margin: clamp(20px, 3vw, 32px) 0 0;
  padding: 0;
}

.page-about .ab-cat li {
  display: grid;
  grid-template-columns: 34px minmax(0, 1fr);
  gap: 2px 14px;
  padding: 16px 0;
  border-top: 1px solid rgba(43, 54, 53, 0.18);
}

.page-about .ab-cat li:last-child {
  border-bottom: 1px solid rgba(43, 54, 53, 0.18);
}

.page-about .ab-cat__num {
  font-family: var(--cg-font-mono);
  font-size: 11.5px;
  letter-spacing: 0.08em;
  color: var(--cg-ink-600);
  padding-top: 4px;
}

.page-about .ab-cat__name {
  font-size: clamp(16px, 1.8vw, 19px);
  font-weight: 700;
  color: var(--cg-ink-950);
  letter-spacing: -0.01em;
}

.page-about .ab-cat__desc {
  grid-column: 2;
  font-size: 14.5px;
  line-height: 1.75;
  color: var(--cg-slate);
}

/* ---------- 流程步骤 ---------- */
.page-about .ab-flow {
  list-style: none;
  margin: clamp(22px, 3vw, 34px) 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(12px, 2vw, 18px);
}

.page-about .ab-flow li {
  position: relative;
  padding: 20px 18px 22px;
  background: rgba(14, 46, 36, 0.6);
  border: var(--ab-hair);
  border-radius: var(--cg-radius);
  transition: border-color var(--cg-dur) var(--cg-ease), transform var(--cg-dur) var(--cg-ease);
}

.page-about .ab-flow li:hover {
  border-color: rgba(214, 168, 75, 0.6);
  transform: translateY(-2px);
}

.page-about .ab-flow__num {
  display: block;
  font-family: var(--cg-font-mono);
  font-size: 10.5px;
  letter-spacing: 0.2em;
  color: var(--cg-gold-500);
}

.page-about .ab-flow__name {
  margin: 10px 0 0;
  font-family: var(--cg-font-display);
  font-size: clamp(18px, 2vw, 22px);
  letter-spacing: -0.01em;
  color: var(--cg-paper);
}

.page-about .ab-flow__text {
  margin: 8px 0 0;
  font-size: 14.5px;
  line-height: 1.78;
  color: rgba(246, 241, 231, 0.72);
}

.page-about .ab-band {
  margin: clamp(18px, 2.6vw, 26px) 0 0;
  padding: 16px 18px;
  display: grid;
  gap: 6px;
  background: rgba(7, 28, 22, 0.72);
  border-left: 2px solid var(--cg-gold-500);
}

.page-about .ab-band__k {
  margin: 0;
  font-family: var(--cg-font-mono);
  font-size: 10.5px;
  letter-spacing: 0.2em;
  color: var(--cg-gold-500);
}

.page-about .ab-band__v {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: rgba(246, 241, 231, 0.8);
}

/* ---------- 图片 ---------- */
.page-about .ab-figure {
  margin: clamp(22px, 3vw, 34px) 0 0;
}

.page-about .ab-figure img {
  display: block;
  width: 100%;
  aspect-ratio: 3 / 2;
  object-fit: cover;
  border: 1px solid rgba(214, 168, 75, 0.22);
  border-radius: var(--cg-radius);
  filter: saturate(0.8);
}

.page-about .ab-figure--soft img {
  aspect-ratio: 10 / 7;
  opacity: 0.86;
}

.page-about .ab-figure__cap {
  margin-top: 10px;
  font-family: var(--cg-font-mono);
  font-size: 11px;
  letter-spacing: 0.05em;
  color: var(--cg-blue-400);
}

/* ---------- 时间轴 ---------- */
.page-about .ab-tl {
  list-style: none;
  margin: clamp(24px, 3.6vw, 40px) 0 0;
  padding: 0;
  position: relative;
}

.page-about .ab-tl::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 10px;
  bottom: 14px;
  width: 1px;
  background: linear-gradient(to bottom, rgba(214, 168, 75, 0.75), rgba(214, 168, 75, 0.06));
}

.page-about .ab-tl__item {
  position: relative;
  padding: 0 0 clamp(22px, 3.2vw, 34px) 28px;
  scroll-margin-top: 100px;
  border-radius: var(--cg-radius);
}

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

.page-about .ab-tl__item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 7px;
  width: 11px;
  height: 11px;
  border-radius: 50%;
  background: var(--cg-ink-950);
  border: 1px solid var(--cg-gold-500);
  transition: background var(--cg-dur) var(--cg-ease);
}

.page-about .ab-tl__item:target {
  background: rgba(214, 168, 75, 0.07);
  box-shadow: 0 0 0 1px rgba(214, 168, 75, 0.55);
}

.page-about .ab-tl__item:target::before {
  background: var(--cg-gold-500);
}

.page-about .ab-tl__year {
  display: block;
  margin-bottom: 6px;
  font-family: var(--cg-font-mono);
  font-size: clamp(18px, 2.2vw, 22px);
  font-weight: 700;
  letter-spacing: -0.01em;
  color: var(--cg-gold-500);
}

.page-about .ab-tl__name {
  margin: 0;
  font-size: clamp(16px, 1.9vw, 20px);
  font-weight: 700;
  color: var(--cg-paper);
}

.page-about .ab-tl__text {
  margin: 8px 0 0;
  max-width: 62ch;
  font-size: 14.5px;
  line-height: 1.82;
  color: rgba(246, 241, 231, 0.72);
}

/* ---------- 合作名录 ---------- */
.page-about .ab-net {
  margin-top: clamp(20px, 3vw, 32px);
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(14px, 2.2vw, 22px);
}

.page-about .ab-net__col {
  padding: clamp(16px, 2.4vw, 24px);
  background: rgba(14, 46, 36, 0.52);
  border: var(--ab-hair);
  border-radius: var(--cg-radius);
}

.page-about .ab-net__title {
  margin: 0;
  font-family: var(--cg-font-mono);
  font-size: 10.5px;
  letter-spacing: 0.2em;
  color: var(--cg-gold-200);
}

.page-about .ab-net__list {
  list-style: none;
  margin: 14px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 8px;
}

.page-about .ab-net__list li {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 10px;
  padding-bottom: 7px;
  border-bottom: 1px dashed rgba(126, 147, 166, 0.24);
  font-size: 14px;
}

.page-about .ab-net__city {
  color: var(--cg-paper);
  font-weight: 600;
}

.page-about .ab-net__kind {
  font-family: var(--cg-font-mono);
  font-size: 11px;
  letter-spacing: 0.06em;
  color: var(--cg-blue-400);
}

.page-about .ab-sub {
  margin: clamp(26px, 3.4vw, 38px) 0 0;
  font-family: var(--cg-font-display);
  font-size: clamp(18px, 2.2vw, 24px);
  letter-spacing: -0.01em;
  color: var(--cg-gold-200);
}

.page-about .ab-team {
  list-style: none;
  margin: 16px 0 0;
  padding: 0;
  border-top: var(--ab-hair-soft);
}

.page-about .ab-team li {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 4px;
  padding: 14px 0;
  border-bottom: var(--ab-hair-soft);
}

.page-about .ab-team__name {
  font-size: 15px;
  font-weight: 700;
  color: var(--cg-paper);
}

.page-about .ab-team__desc {
  font-size: 14px;
  line-height: 1.75;
  color: rgba(246, 241, 231, 0.68);
}

/* ---------- 运营信息 ---------- */
.page-about .ab-sec--info .ab-info {
  margin: clamp(20px, 3vw, 30px) 0 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  background: rgba(43, 54, 53, 0.2);
  border: 1px solid rgba(43, 54, 53, 0.2);
  border-radius: var(--cg-radius);
  overflow: hidden;
}

.page-about .ab-info__cell {
  background: var(--cg-paper);
  padding: 16px 18px;
}

.page-about .ab-info dt {
  font-family: var(--cg-font-mono);
  font-size: 10.5px;
  letter-spacing: 0.18em;
  color: var(--cg-ink-600);
}

.page-about .ab-info dd {
  margin: 8px 0 0;
  font-family: var(--cg-font-mono);
  font-size: clamp(14px, 1.6vw, 16px);
  line-height: 1.6;
  color: var(--cg-ink-950);
  word-break: break-word;
}

.page-about .ab-scope {
  margin: 18px 0 0;
  max-width: 68ch;
  font-size: 13.5px;
  line-height: 1.85;
  color: rgba(43, 54, 53, 0.82);
}

.page-about .ab-cta {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 24px;
}

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

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

  .page-about .ab-team li {
    grid-template-columns: 150px minmax(0, 1fr);
    gap: 14px;
  }

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

@media (min-width: 840px) {
  .page-about .ab-hero__grid {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
  }

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

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

  .page-about .ab-cat li {
    grid-template-columns: 44px 190px minmax(0, 1fr);
    align-items: baseline;
    gap: 0 20px;
  }

  .page-about .ab-cat__desc {
    grid-column: 3;
  }

  .page-about .ab-tl::before {
    left: 96px;
  }

  .page-about .ab-tl__item {
    display: grid;
    grid-template-columns: 88px minmax(0, 1fr);
    gap: 0 30px;
    padding-left: 0;
    padding-right: 12px;
  }

  .page-about .ab-tl__item::before {
    left: 91px;
  }

  .page-about .ab-tl__year {
    text-align: right;
    margin-bottom: 0;
    padding-top: 2px;
  }
}

@media (min-width: 1040px) {
  .page-about .ab-layout {
    grid-template-columns: 198px minmax(0, 1fr);
    gap: clamp(32px, 4vw, 60px);
    align-items: start;
  }

  .page-about .ab-rail {
    position: sticky;
    top: 96px;
    overflow: visible;
    border-top: 0;
    border-bottom: 0;
    padding-block: 0;
  }

  .page-about .ab-rail__list {
    flex-direction: column;
    gap: 2px;
    border-left: 1px solid rgba(240, 217, 166, 0.16);
  }

  .page-about .ab-rail__link {
    border: 0;
    border-radius: 0;
    padding: 8px 0 8px 14px;
    font-size: 13.5px;
    position: relative;
  }

  .page-about .ab-rail__link::before {
    content: "";
    position: absolute;
    left: -1px;
    top: 50%;
    width: 2px;
    height: 0;
    background: var(--cg-gold-500);
    transform: translateY(-50%);
    transition: height var(--cg-dur) var(--cg-ease);
  }

  .page-about .ab-rail__link:hover::before,
  .page-about .ab-rail__link:focus-visible::before {
    height: 100%;
  }

  .page-about .ab-rail__years {
    display: block;
    margin-top: 26px;
    padding-top: 18px;
    border-top: var(--ab-hair-soft);
  }

  .page-about .ab-rail__yearlist {
    list-style: none;
    margin: 0;
    padding: 0;
    display: flex;
    flex-direction: column;
    gap: 4px;
  }

  .page-about .ab-rail__yearlink {
    display: block;
    padding: 4px 0 4px 14px;
    font-family: var(--cg-font-mono);
    font-size: 12.5px;
    text-decoration: none;
    color: var(--cg-blue-400);
    border-left: 1px solid transparent;
    transition: color var(--cg-dur) var(--cg-ease), border-color var(--cg-dur) var(--cg-ease);
  }

  .page-about .ab-rail__yearlink:hover,
  .page-about .ab-rail__yearlink:focus-visible {
    color: var(--cg-gold-200);
    border-left-color: rgba(214, 168, 75, 0.6);
  }

  .page-about .ab-note {
    margin-left: auto;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .ab-flow li,
  .page-about .ab-rail__link::before {
    transition: none;
  }

  .page-about .ab-flow li:hover {
    transform: none;
  }
}