.page-about {
  --about-rail: 208px;
  --about-gap: 52px;
  background-color: var(--bg);
  color: var(--ink);
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.85;
  overflow-x: hidden;
}

/* ---------- 首屏档案区 ---------- */

.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding: 32px 0 0;
  border-bottom: 1px solid var(--line);
  background:
    radial-gradient(120% 90% at 85% 0%, rgba(14, 43, 51, 0.95) 0%, rgba(8, 24, 43, 0) 62%),
    linear-gradient(180deg, rgba(36, 27, 74, 0.42) 0%, rgba(8, 24, 43, 0) 55%);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 0;
  background-image:
    linear-gradient(var(--line) 1px, transparent 1px),
    linear-gradient(90deg, var(--line) 1px, transparent 1px);
  background-size: var(--grid-step) var(--grid-step);
  opacity: 0.4;
  pointer-events: none;
  -webkit-mask-image: linear-gradient(180deg, #000 0%, transparent 82%);
  mask-image: linear-gradient(180deg, #000 0%, transparent 82%);
}

.page-about .about-hero > .container {
  position: relative;
  z-index: 1;
}

.page-about .about-hero__watermark {
  position: absolute;
  right: -8px;
  top: -18px;
  z-index: 0;
  font-family: var(--font-head);
  font-size: clamp(120px, 30vw, 300px);
  font-weight: 700;
  line-height: 0.78;
  letter-spacing: -0.05em;
  color: transparent;
  -webkit-text-stroke: 1px rgba(47, 243, 208, 0.22);
  pointer-events: none;
  user-select: none;
}

.page-about .about-hero .breadcrumbs {
  margin-bottom: 26px;
}

.page-about .about-hero__eyebrow {
  margin: 0 0 12px;
}

.page-about .about-hero__title {
  margin: 0 0 20px;
  font-family: var(--font-head);
  font-weight: 600;
  font-size: clamp(34px, 7.4vw, 62px);
  line-height: 1.06;
  letter-spacing: -0.012em;
  color: var(--ink);
  max-width: 15em;
}

.page-about .about-hero__title em {
  font-style: normal;
  color: var(--cyan);
  box-shadow: inset 0 -0.16em 0 rgba(47, 243, 208, 0.22);
}

.page-about .about-hero__lead {
  max-width: 34em;
  color: var(--ink-2);
  margin: 0 0 30px;
}

.page-about .about-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 0 0 34px;
  background-color: var(--line);
  border: 1px solid var(--line);
}

.page-about .about-stats__cell {
  background-color: var(--bg);
  padding: 14px 16px 16px;
}

.page-about .about-stats dt {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--ink-2);
  text-transform: uppercase;
}

.page-about .about-stats dd {
  margin: 6px 0 0;
  font-family: var(--font-head);
  font-weight: 600;
  font-size: 30px;
  line-height: 1;
  color: var(--cyan);
}

.page-about .about-cover {
  margin: 0 0 0;
}

.page-about .about-cover .media__img {
  width: 100%;
  height: auto;
  max-height: 280px;
  object-fit: cover;
  display: block;
  border: 1px solid var(--line);
  border-bottom: 0;
}

.page-about .about-cover .media__caption {
  display: block;
  padding: 8px 0 14px;
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--ink-2);
  border-bottom: 0;
}

/* ---------- 双栏主体 ---------- */

.page-about .about-body {
  padding-block: 48px 72px;
}

.page-about .about-years {
  margin-bottom: 40px;
  border-top: 1px solid var(--line);
  padding-top: 14px;
}

.page-about .about-years__title {
  margin: 0 0 12px;
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--ink-2);
}

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

.page-about .about-years__item {
  flex: 0 0 auto;
}

.page-about .about-years__link {
  display: flex;
  align-items: baseline;
  gap: 8px;
  padding: 8px 12px;
  border: 1px solid var(--line);
  background-color: rgba(14, 43, 51, 0.35);
  text-decoration: none;
  white-space: nowrap;
  transition: border-color 120ms ease, color 120ms ease, background-color 120ms ease;
}

.page-about .about-years__num {
  font-family: var(--font-head);
  font-weight: 600;
  font-size: 17px;
  line-height: 1;
  color: var(--ink);
}

.page-about .about-years__label {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--ink-2);
}

.page-about .about-years__link:hover,
.page-about .about-years__link:focus-visible {
  border-color: var(--cyan);
  background-color: rgba(47, 243, 208, 0.08);
}

.page-about .about-years__link:hover .about-years__num,
.page-about .about-years__link:focus-visible .about-years__num {
  color: var(--cyan);
}

/* ---------- 章节通用 ---------- */

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

.page-about .about-section {
  padding-bottom: 46px;
  border-bottom: 1px solid var(--line);
  margin-bottom: 46px;
}

.page-about .about-section:last-of-type {
  border-bottom: 0;
  margin-bottom: 0;
}

.page-about .about-section > .section-head {
  margin-bottom: 18px;
}

.page-about .about-section__title {
  margin: 6px 0 0;
  font-family: var(--font-head);
  font-weight: 600;
  font-size: clamp(24px, 4.6vw, 38px);
  line-height: 1.16;
  letter-spacing: -0.01em;
  color: var(--ink);
  max-width: 20em;
}

.page-about .about-section .prose {
  max-width: 34em;
  margin: 0 0 20px;
  color: var(--ink-2);
}

.page-about .about-section .prose a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(47, 243, 208, 0.4);
}

.page-about .about-section .prose a:hover {
  border-bottom-color: var(--cyan);
}

.page-about .about-section--zone {
  padding-left: 18px;
  padding-right: 18px;
  border-bottom: 0;
  background-color: var(--zone);
  border-left: 2px solid var(--cyan);
}

/* ---------- 业务范围 ---------- */

.page-about .about-scope {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  background-color: var(--line);
  border: 1px solid var(--line);
  margin-bottom: 22px;
}

.page-about .scope-item {
  background-color: var(--bg);
  padding: 20px 18px 22px;
}

.page-about .scope-item__num {
  display: inline-block;
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--amber);
}

.page-about .scope-item__title {
  margin: 8px 0 8px;
  font-family: var(--font-head);
  font-weight: 600;
  font-size: 19px;
  line-height: 1.3;
  color: var(--ink);
}

.page-about .scope-item__text {
  margin: 0;
  font-size: 14px;
  color: var(--ink-2);
}

.page-about .about-scope__foot {
  margin: 0;
  padding-left: 14px;
  border-left: 2px solid var(--wine);
  font-size: 14px;
  color: var(--ink-2);
}

/* ---------- 版本年表 ---------- */

.page-about .about-timeline__fig {
  margin: 0 0 30px;
}

.page-about .about-timeline__fig .media__img {
  width: 100%;
  height: auto;
  display: block;
  border: 1px solid var(--line);
  object-fit: cover;
}

.page-about .about-timeline__fig .media__caption {
  display: block;
  padding-top: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--ink-2);
}

.page-about .timeline {
  position: relative;
  margin: 0;
  padding: 0 0 0 28px;
  list-style: none;
}

.page-about .timeline::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 8px;
  bottom: 12px;
  width: 1px;
  background: linear-gradient(180deg, var(--cyan) 0%, var(--amber) 48%, var(--wine) 100%);
  opacity: 0.7;
}

.page-about .tl-item {
  position: relative;
  padding-bottom: 30px;
  scroll-margin-top: 96px;
}

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

.page-about .tl-item::before {
  content: "";
  position: absolute;
  left: -27px;
  top: 8px;
  width: 9px;
  height: 9px;
  background-color: var(--bg);
  border: 1px solid var(--cyan);
  transform: rotate(45deg);
}

.page-about .tl-item:nth-child(2)::before {
  border-color: var(--amber);
}

.page-about .tl-item:nth-child(4)::before {
  border-color: var(--wine);
}

.page-about .tl-item__year {
  margin: 0 0 4px;
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--cyan);
}

.page-about .tl-item:nth-child(2) .tl-item__year {
  color: var(--amber);
}

.page-about .tl-item:nth-child(4) .tl-item__year {
  color: var(--wine);
}

.page-about .tl-item__title {
  margin: 0 0 8px;
  font-family: var(--font-head);
  font-weight: 600;
  font-size: 21px;
  line-height: 1.3;
  color: var(--ink);
}

.page-about .tl-item__text {
  margin: 0 0 10px;
  font-size: 14px;
  color: var(--ink-2);
  max-width: 34em;
}

.page-about .tl-more > summary {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 3px 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--cyan);
  cursor: pointer;
  list-style: none;
}

.page-about .tl-more > summary::-webkit-details-marker {
  display: none;
}

.page-about .tl-more > summary::before {
  content: "+";
  font-size: 15px;
  line-height: 1;
  color: var(--amber);
}

.page-about .tl-more[open] > summary::before {
  content: "−";
}

.page-about .tl-more > summary:focus-visible {
  outline: 1px solid var(--cyan);
  outline-offset: 3px;
}

.page-about .tl-more__list {
  margin: 10px 0 0;
  padding: 12px 16px 12px 30px;
  list-style: none;
  border-left: 2px solid var(--line);
  background-color: rgba(14, 43, 51, 0.5);
}

.page-about .tl-more__list li {
  position: relative;
  font-size: 13px;
  color: var(--ink-2);
  padding: 3px 0;
}

.page-about .tl-more__list li::before {
  content: "—";
  position: absolute;
  left: -18px;
  color: var(--muted);
}

.page-about .about-timeline__foot {
  margin: 26px 0 0;
  font-size: 14px;
  color: var(--ink-2);
}

.page-about .about-timeline__foot a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(47, 243, 208, 0.4);
}

.page-about .about-timeline__foot a:hover {
  border-bottom-color: var(--cyan);
}

/* ---------- 品牌专区 ---------- */

.page-about .zone-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 26px;
}

.page-about .zone-grid__aside {
  border-top: 1px solid rgba(47, 243, 208, 0.35);
  padding-top: 16px;
}

.page-about .zone-note__title {
  margin: 0 0 12px;
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--cyan);
}

.page-about .zone-links {
  margin: 0 0 16px;
  padding: 0;
  list-style: none;
}

.page-about .zone-links li {
  border-bottom: 1px solid var(--line);
}

.page-about .zone-links a {
  display: block;
  padding: 11px 0;
  font-size: 14px;
  color: var(--ink);
  text-decoration: none;
  transition: color 120ms ease, padding-left 120ms ease;
}

.page-about .zone-links a::before {
  content: "›";
  margin-right: 8px;
  color: var(--amber);
}

.page-about .zone-links a:hover,
.page-about .zone-links a:focus-visible {
  color: var(--cyan);
  padding-left: 6px;
}

.page-about .zone-note__foot {
  margin: 0;
}

/* ---------- 服务团队 ---------- */

.page-about .about-team__fig {
  margin: 0 0 26px;
}

.page-about .about-team__fig .media__img {
  width: 100%;
  height: auto;
  display: block;
  border: 1px solid var(--line);
  object-fit: cover;
}

.page-about .about-team__fig .media__caption {
  display: block;
  padding-top: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--ink-2);
}

.page-about .team-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  background-color: var(--line);
  border: 1px solid var(--line);
  margin-bottom: 24px;
}

.page-about .team-cell {
  background-color: var(--bg);
  padding: 20px 18px 22px;
  transition: background-color 160ms ease;
}

.page-about .team-cell:hover {
  background-color: rgba(14, 43, 51, 0.85);
}

.page-about .team-cell__num {
  display: block;
  font-family: var(--font-head);
  font-weight: 600;
  font-size: 26px;
  line-height: 1;
  color: var(--line);
  margin-bottom: 10px;
}

.page-about .team-cell__title {
  margin: 0 0 8px;
  font-family: var(--font-head);
  font-weight: 600;
  font-size: 19px;
  color: var(--ink);
}

.page-about .team-cell__text {
  margin: 0 0 14px;
  font-size: 14px;
  color: var(--ink-2);
}

.page-about .team-cell__link {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--muted);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color 140ms ease, border-color 140ms ease;
}

.page-about .team-cell:hover .team-cell__link,
.page-about .team-cell__link:focus-visible {
  color: var(--cyan);
  border-bottom-color: var(--cyan);
}

.page-about .about-team__callout {
  margin: 0;
}

/* ---------- 合作生态 ---------- */

.page-about .partner-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
  margin-bottom: 24px;
}

.page-about .partner-item {
  padding: 18px 18px 20px;
  border: 1px solid var(--line);
  background-color: var(--bg-legacy);
}

.page-about .partner-item__key {
  margin: 0;
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--muted);
}

.page-about .partner-item__val {
  margin: 8px 0 10px;
  font-family: var(--font-head);
  font-weight: 600;
  font-size: 34px;
  line-height: 1;
  color: var(--amber);
  letter-spacing: -0.01em;
}

.page-about .partner-item__desc {
  margin: 0;
  font-size: 14px;
  color: var(--ink-2);
}

.page-about .about-partner__callout {
  margin: 0;
}

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

/* ---------- 结尾引导 ---------- */

.page-about .about-cta {
  border-bottom: 0;
}

.page-about .about-cta__inner {
  padding: 30px 20px 32px;
  border: 1px solid var(--line);
  border-left: 2px solid var(--cyan);
  background:
    linear-gradient(135deg, rgba(14, 43, 51, 0.9) 0%, rgba(8, 24, 43, 0.4) 70%);
}

.page-about .about-cta__title {
  margin: 0 0 10px;
  font-family: var(--font-head);
  font-weight: 600;
  font-size: clamp(22px, 4.2vw, 32px);
  line-height: 1.2;
  color: var(--ink);
}

.page-about .about-cta__text {
  margin: 0 0 22px;
  max-width: 32em;
  color: var(--ink-2);
  font-size: 14px;
}

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

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

/* ---------- 中等屏幕 ---------- */

@media (min-width: 640px) {
  .page-about .about-scope {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

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

  .page-about .about-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    max-width: 620px;
  }
}

@media (min-width: 768px) {
  .page-about .team-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .about-cta__inner {
    padding: 40px 36px 42px;
  }
}

/* ---------- 桌面：侧栏年份索引 + 宽栏档案正文 ---------- */

@media (min-width: 1024px) {
  .page-about .about-hero {
    padding-top: 44px;
  }

  .page-about .about-body {
    display: grid;
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    gap: var(--about-gap);
    align-items: start;
    padding-block: 62px 96px;
  }

  .page-about .about-years {
    position: sticky;
    top: 96px;
    margin-bottom: 0;
    border-top: 1px solid var(--line);
    border-left: 1px solid var(--line);
    padding: 14px 0 14px 14px;
  }

  .page-about .about-years__list {
    display: block;
    overflow: visible;
  }

  .page-about .about-years__item + .about-years__item {
    margin-top: 4px;
  }

  .page-about .about-years__link {
    width: 100%;
    border: 0;
    border-left: 2px solid transparent;
    background-color: transparent;
    padding: 8px 8px 8px 12px;
    flex-direction: column;
    align-items: flex-start;
    gap: 2px;
  }

  .page-about .about-years__link:hover,
  .page-about .about-years__link:focus-visible {
    border-left-color: var(--cyan);
    background-color: rgba(47, 243, 208, 0.06);
  }

  .page-about .about-years__num {
    font-size: 20px;
  }

  .page-about .zone-grid {
    grid-template-columns: minmax(0, 1fr) 260px;
    gap: 40px;
  }

  .page-about .about-section--zone {
    padding-left: 28px;
    padding-right: 28px;
  }

  .page-about .about-cover .media__img {
    max-height: 330px;
  }
}

@media (min-width: 1200px) {
  .page-about .timeline {
    padding-left: 34px;
  }

  .page-about .tl-item::before {
    left: -33px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about * {
    transition: none !important;
    animation: none !important;
    scroll-behavior: auto !important;
  }
}