.page-about {
  background: var(--paper-100);
  color: var(--ink-900);
}

.page-about .breadcrumbs {
  padding: 22px 0 0;
  margin: 0;
}

/* ---------- 首屏 ---------- */

.page-about .about-hero {
  padding: 28px 0 52px;
}

.page-about .about-hero__grid {
  display: grid;
  gap: 30px;
}

.page-about .about-hero__lead .index-label {
  display: block;
  color: var(--inkgold-600);
}

.page-about .about-hero h1 {
  margin: 14px 0 0;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(27px, 5.4vw, 46px);
  line-height: 1.26;
  letter-spacing: -0.02em;
  color: var(--ink-900);
  max-width: 20ch;
}

.page-about .about-hero h1::after {
  content: "";
  display: block;
  width: 66px;
  height: 3px;
  margin-top: 22px;
  border-radius: 2px;
  background: linear-gradient(90deg, var(--gold-500), var(--gold-300));
}

.page-about .about-hero__intro {
  margin: 22px 0 0;
  max-width: 60ch;
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.9;
  letter-spacing: 0.01em;
  color: var(--ink-500);
}

.page-about .about-facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--hairline);
  border: 1px solid var(--hairline);
  border-radius: var(--radius-md);
  overflow: hidden;
}

.page-about .about-facts__cell {
  background: var(--paper-000);
  padding: 16px 18px 18px;
  min-width: 0;
}

.page-about .about-facts__k {
  display: block;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--slate-400);
}

.page-about .about-facts__v {
  display: block;
  margin-top: 8px;
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(19px, 2.6vw, 25px);
  font-weight: 700;
  letter-spacing: -0.01em;
  color: var(--ink-900);
  word-break: break-word;
}

.page-about .about-facts__v small {
  margin-left: 3px;
  font-size: 12px;
  font-weight: 400;
  letter-spacing: 0.04em;
  color: var(--slate-400);
}

/* ---------- 章节骨架 ---------- */

.page-about .about-section {
  padding: 52px 0;
  border-top: 1px solid var(--hairline);
}

.page-about .about-section__head {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px 14px;
  margin-bottom: 30px;
}

.page-about .about-section__no {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  flex: 0 0 auto;
  width: 31px;
  height: 31px;
  border: 1px solid rgba(168, 69, 47, 0.42);
  border-radius: 7px;
  background: rgba(168, 69, 47, 0.06);
  color: var(--seal-600);
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.04em;
}

.page-about .about-section__title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(20px, 3vw, 28px);
  line-height: 1.36;
  letter-spacing: -0.015em;
  color: var(--ink-900);
}

.page-about .about-section__sub {
  flex: 1 1 100%;
  margin: 0;
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.8;
  color: var(--slate-400);
}

/* ---------- 主栏 + 旁注 ---------- */

.page-about .about-split {
  display: grid;
  gap: 30px;
}

.page-about .about-split__main {
  min-width: 0;
}

.page-about .prose p {
  margin: 0 0 16px;
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.92;
  letter-spacing: 0.01em;
  color: var(--ink-500);
}

.page-about .about-aside {
  display: grid;
  gap: 16px;
  align-content: start;
  min-width: 0;
}

.page-about .aside-term {
  padding: 15px 17px;
  border-left: 3px solid var(--gold-300);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  background: rgba(232, 224, 208, 0.55);
  outline: none;
  transition: border-color 0.3s var(--ease), background 0.3s var(--ease);
}

.page-about .aside-term:hover,
.page-about .aside-term:focus,
.page-about .aside-term:focus-visible {
  border-left-color: var(--gold-500);
  background: var(--paper-200);
}

.page-about .aside-term__name {
  display: block;
  margin-bottom: 8px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--inkgold-600);
}

.page-about .aside-term::after {
  content: "＋ 展开";
  display: block;
  margin-top: 7px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--gold-500);
}

.page-about .aside-term:hover::after,
.page-about .aside-term:focus::after,
.page-about .aside-term:focus-visible::after {
  content: "－ 收起";
}

.page-about .aside-term__def {
  margin: 0;
  max-height: 3.7em;
  overflow: hidden;
  font-family: var(--font-body);
  font-size: 14px;
  line-height: 1.85;
  color: var(--ink-500);
  transition: max-height 0.4s var(--ease);
}

.page-about .aside-term:hover .aside-term__def,
.page-about .aside-term:focus .aside-term__def,
.page-about .aside-term:focus-visible .aside-term__def {
  max-height: 22em;
}

.page-about .aside-note {
  padding: 18px 19px 20px;
  background: var(--paper-200);
  border: 1px solid rgba(198, 161, 91, 0.38);
  border-radius: var(--radius-md);
}

.page-about .aside-note__cap {
  display: block;
  margin-bottom: 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--inkgold-600);
}

.page-about .aside-note p {
  margin: 0;
  font-family: var(--font-body);
  font-size: 14px;
  line-height: 1.88;
  color: var(--ink-500);
}

/* ---------- 图表 ---------- */

.page-about .about-figure {
  margin: 24px 0 0;
  border-radius: var(--radius-md);
  overflow: hidden;
  background: var(--paper-200);
}

.page-about .about-figure--band {
  margin-top: 28px;
}

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

.page-about .about-figure__cap {
  display: block;
  padding: 11px 16px 13px;
  font-family: var(--font-body);
  font-size: 13px;
  line-height: 1.7;
  color: var(--slate-400);
  background: var(--paper-200);
  border-top: 1px solid rgba(198, 161, 91, 0.3);
}

.page-about .about-table__caption {
  padding: 0 0 12px;
  text-align: left;
  font-family: var(--font-body);
  font-size: 13px;
  line-height: 1.7;
  color: var(--slate-400);
}

/* ---------- 五步流程 ---------- */

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

.page-about .steps__item {
  background: var(--paper-000);
  padding: 20px 18px 22px;
  min-width: 0;
}

.page-about .steps__no {
  display: block;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--gold-500);
}

.page-about .steps__title {
  margin: 10px 0 8px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 16px;
  letter-spacing: -0.01em;
  color: var(--ink-900);
}

.page-about .steps__text {
  margin: 0;
  font-family: var(--font-body);
  font-size: 14px;
  line-height: 1.82;
  color: var(--ink-500);
}

.page-about .output-row {
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
  margin-top: 26px;
}

.page-about .output-row__item {
  padding: 16px 18px 18px;
  border-radius: var(--radius-md);
  background: var(--paper-200);
  border: 1px solid rgba(198, 161, 91, 0.3);
}

.page-about .output-row__n {
  display: block;
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 24px;
  font-weight: 700;
  letter-spacing: -0.01em;
  color: var(--ink-900);
}

.page-about .output-row__k {
  display: block;
  margin-top: 6px;
  font-family: var(--font-body);
  font-size: 13px;
  line-height: 1.7;
  color: var(--slate-400);
}

/* ---------- 发展节点时间轴 ---------- */

.page-about .about-timeline-wrap {
  position: relative;
  overflow: hidden;
  padding: 28px 20px;
  border: 1px solid var(--hairline);
  border-radius: var(--radius-lg);
  background: var(--paper-000);
}

.page-about .about-timeline-bg {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.11;
  pointer-events: none;
}

.page-about .timeline {
  position: relative;
  z-index: 1;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .timeline::before {
  content: "";
  position: absolute;
  left: 9px;
  top: 10px;
  bottom: 10px;
  width: 1px;
  background: linear-gradient(180deg, var(--gold-500), rgba(198, 161, 91, 0.12));
}

.page-about .timeline__item {
  position: relative;
  padding: 0 0 26px 34px;
}

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

.page-about .timeline__item::before {
  content: "";
  position: absolute;
  left: 4px;
  top: 5px;
  z-index: 2;
  width: 11px;
  height: 11px;
  border-radius: 50%;
  background: var(--paper-000);
  border: 2px solid var(--gold-500);
  transition: transform 0.35s var(--ease), background 0.35s var(--ease);
}

.page-about .timeline__year {
  display: inline-block;
  margin-bottom: 8px;
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.05em;
  color: var(--inkgold-600);
}

.page-about .timeline__card {
  padding: 16px 18px 18px;
  border: 1px solid var(--hairline);
  border-radius: var(--radius-md);
  background: var(--paper-000);
  outline: none;
  transition: transform 0.35s var(--ease), border-color 0.35s var(--ease), box-shadow 0.35s var(--ease);
}

.page-about .timeline__item:hover .timeline__card,
.page-about .timeline__item:focus-within .timeline__card {
  transform: translateY(-3px) scale(1.01);
  border-color: var(--gold-500);
  box-shadow: 0 16px 32px -24px rgba(11, 27, 46, 0.55);
}

.page-about .timeline__item:hover::before,
.page-about .timeline__item:focus-within::before {
  background: var(--gold-500);
  transform: scale(1.3);
}

.page-about .timeline__tag {
  display: inline-flex;
  align-items: center;
  margin-bottom: 9px;
  padding: 3px 11px;
  border: 1px solid rgba(198, 161, 91, 0.45);
  border-radius: var(--radius-pill);
  background: rgba(228, 206, 154, 0.32);
  color: var(--inkgold-600);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  transition: background 0.3s var(--ease), border-color 0.3s var(--ease);
}

.page-about .timeline__item:hover .timeline__tag,
.page-about .timeline__item:focus-within .timeline__tag {
  background: var(--gold-300);
  border-color: var(--gold-500);
}

.page-about .timeline__title {
  margin: 0 0 7px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 16px;
  letter-spacing: -0.01em;
  color: var(--ink-900);
}

.page-about .timeline__text {
  margin: 0;
  font-family: var(--font-body);
  font-size: 14px;
  line-height: 1.86;
  color: var(--ink-500);
}

/* ---------- 服务支持 ---------- */

.page-about .support-grid {
  display: grid;
  gap: 16px;
}

.page-about .support-card {
  padding: 22px 20px 24px;
  border: 1px solid var(--hairline);
  border-radius: var(--radius-md);
  background: var(--paper-000);
  min-width: 0;
}

.page-about .support-card--ink {
  background: var(--ink-900);
  border-color: var(--ink-700);
}

.page-about .support-card__title {
  margin: 14px 0 10px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 17px;
  letter-spacing: -0.01em;
  color: var(--ink-900);
}

.page-about .support-card__text {
  margin: 0;
  font-family: var(--font-body);
  font-size: 14px;
  line-height: 1.86;
  color: var(--ink-500);
  word-break: break-word;
}

.page-about .support-card--ink .support-card__title {
  color: var(--paper-100);
}

.page-about .support-card--ink .support-card__text {
  color: rgba(245, 240, 230, 0.76);
}

/* ---------- 合作与资质 ---------- */

.page-about .credentials {
  margin: 0;
  padding: 0;
  list-style: none;
  border: 1px solid var(--hairline);
  border-radius: var(--radius-md);
  overflow: hidden;
  background: var(--paper-000);
}

.page-about .credentials__row {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: 8px 20px;
  padding: 16px 18px;
  border-bottom: 1px solid var(--hairline);
}

.page-about .credentials__row:last-child {
  border-bottom: 0;
}

.page-about .credentials__row:nth-child(even) {
  background: rgba(232, 224, 208, 0.5);
}

.page-about .credentials__k {
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.75;
  color: var(--ink-500);
  min-width: 0;
}

.page-about .credentials__v {
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 19px;
  font-weight: 700;
  letter-spacing: 0.01em;
  color: var(--ink-900);
  word-break: break-word;
}

.page-about .credentials__v small {
  margin-left: 3px;
  font-size: 12px;
  font-weight: 400;
  color: var(--slate-400);
}

/* ---------- 收尾 ---------- */

.page-about .about-cta {
  padding: 8px 0 64px;
}

.page-about .about-cta__box {
  display: grid;
  gap: 24px;
  padding: 30px 22px;
  border-radius: var(--radius-lg);
  background: linear-gradient(135deg, var(--ink-900) 0%, var(--ink-700) 100%);
  border: 1px solid var(--ink-700);
}

.page-about .about-cta__text .index-label {
  display: block;
  color: var(--gold-300);
}

.page-about .about-cta__text h2 {
  margin: 12px 0 12px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(20px, 3vw, 27px);
  line-height: 1.38;
  letter-spacing: -0.015em;
  color: var(--paper-100);
}

.page-about .about-cta__text p {
  margin: 0;
  max-width: 56ch;
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.88;
  color: rgba(245, 240, 230, 0.76);
}

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

/* ---------- 响应式 ---------- */

@media (min-width: 640px) {
  .page-about .output-row {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

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

@media (min-width: 760px) {
  .page-about .about-section {
    padding: 62px 0;
  }

  .page-about .steps {
    grid-template-columns: repeat(5, minmax(0, 1fr));
  }

  .page-about .about-timeline-wrap {
    padding: 40px 36px;
  }

  .page-about .timeline::before {
    left: 72px;
  }

  .page-about .timeline__item {
    padding: 0 0 30px 104px;
  }

  .page-about .timeline__item::before {
    left: 67px;
  }

  .page-about .timeline__year {
    position: absolute;
    left: 0;
    top: 2px;
    width: 56px;
    margin: 0;
    text-align: right;
  }

  .page-about .about-cta__box {
    padding: 40px 38px;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero {
    padding: 36px 0 60px;
  }

  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
    gap: 54px;
    align-items: end;
  }

  .page-about .about-split {
    grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
    gap: 48px;
  }

  .page-about .about-cta__box {
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: center;
    gap: 36px;
  }

  .page-about .about-cta__actions {
    flex-direction: column;
    align-items: stretch;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .aside-term__def,
  .page-about .aside-term,
  .page-about .timeline__card,
  .page-about .timeline__item::before,
  .page-about .timeline__tag {
    transition: none;
  }

  .page-about .timeline__item:hover .timeline__card,
  .page-about .timeline__item:focus-within .timeline__card {
    transform: none;
  }

  .page-about .timeline__item:hover::before,
  .page-about .timeline__item:focus-within::before {
    transform: none;
  }
}