.page-about {
  --about-axis: 84px;
  --about-gap: clamp(20px, 3vw, 40px);
  display: block;
  background: var(--ink);
  color: var(--cream);
  overflow-x: hidden;
}

/* ---------- 面包屑 ---------- */
.page-about .crumbs {
  padding-top: calc(var(--header-h) + 20px);
  padding-bottom: 8px;
}
.page-about .crumbs .breadcrumb {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  list-style: none;
  margin: 0;
  padding: 0;
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--muted);
}
.page-about .crumbs .breadcrumb li + li::before {
  content: "/";
  margin-right: 8px;
  color: var(--line-strong);
}
.page-about .crumbs .breadcrumb a {
  color: var(--muted);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}
.page-about .crumbs .breadcrumb a:hover {
  color: var(--cyan);
  border-bottom-color: var(--line-accent);
}
.page-about .crumbs .breadcrumb li[aria-current] {
  color: var(--cyan);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding: clamp(14px, 2.5vw, 26px) 0 clamp(48px, 7vw, 84px);
}
.page-about .about-hero::before {
  content: "";
  position: absolute;
  top: -14%;
  right: -10%;
  width: min(56vw, 660px);
  aspect-ratio: 1 / 1.1;
  background: linear-gradient(152deg, rgba(61, 240, 196, 0.2) 0%, rgba(13, 42, 31, 0.96) 58%, rgba(6, 23, 15, 0) 100%);
  clip-path: polygon(34% 0, 100% 0, 100% 100%, 0 76%);
  pointer-events: none;
}
.page-about .about-hero-inner {
  position: relative;
  z-index: 1;
}
.page-about .about-hero-inner .type-index {
  margin: 0 0 18px;
}
.page-about .about-hero .type-display {
  margin: 0;
  max-width: 17ch;
  font-size: clamp(38px, 8vw, 88px);
  line-height: 1.02;
  letter-spacing: -0.02em;
  font-weight: 900;
  color: var(--cream);
}
.page-about .about-hero .type-lede {
  margin: clamp(20px, 3vw, 30px) 0 0;
  max-width: 62ch;
  font-size: clamp(15px, 1.5vw, 17px);
  line-height: 1.75;
  color: var(--mist);
}
.page-about .about-jump {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 8px 14px;
  margin: clamp(24px, 3.5vw, 38px) 0 0;
  padding: 0;
}
.page-about .about-jump a {
  display: inline-block;
  padding: 6px 12px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--muted);
  text-decoration: none;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease), background var(--dur) var(--ease);
}
.page-about .about-jump a:hover,
.page-about .about-jump a:focus-visible {
  color: var(--ink);
  background: var(--cyan);
  border-color: var(--cyan);
}
.page-about .about-hero-mark {
  position: absolute;
  right: clamp(6px, 3vw, 48px);
  bottom: -0.06em;
  font-family: var(--font-display);
  font-size: clamp(76px, 17vw, 210px);
  font-weight: 900;
  line-height: 0.78;
  letter-spacing: -0.05em;
  color: transparent;
  -webkit-text-stroke: 1px rgba(61, 240, 196, 0.2);
  pointer-events: none;
  user-select: none;
}

/* ---------- 关键数字带 ---------- */
.page-about .about-facts {
  list-style: none;
  margin: 0 auto;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}
.page-about .about-facts .stat {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 20px 18px;
  background: var(--panel);
}
.page-about .about-facts .stat-value {
  font-size: clamp(28px, 4vw, 42px);
  line-height: 1;
  color: var(--cyan);
  font-weight: 500;
}
.page-about .about-facts .stat-label {
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--muted);
}

/* ---------- 首屏配图 ---------- */
.page-about .about-figure {
  margin: clamp(32px, 5vw, 60px) auto 0;
}
.page-about .about-figure .media,
.page-about .tl-banner .media,
.page-about .partners-media .media {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--panel);
}
.page-about .about-figure img,
.page-about .tl-banner img,
.page-about .partners-media img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  filter: saturate(0.82) contrast(1.04);
}
.page-about .media-caption {
  margin: 10px 0 0;
  font-size: 12px;
  line-height: 1.7;
  color: var(--muted);
  max-width: 68ch;
}

/* ---------- 通用区块头部 ---------- */
.page-about .section-head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
  padding-bottom: 14px;
  border-bottom: 1px solid var(--line);
}
.page-about .section-head .type-h1 {
  margin: 0;
  font-size: clamp(26px, 4.4vw, 48px);
  line-height: 1.08;
  letter-spacing: -0.015em;
  color: var(--cream);
}
.page-about .section-head .type-index {
  margin: 0;
}
.page-about .type-lede {
  margin: clamp(18px, 2.5vw, 26px) 0 0;
  max-width: 64ch;
  font-size: 15.5px;
  line-height: 1.75;
  color: var(--mist);
}

/* ---------- 时间线 ---------- */
.page-about .tl-section .type-lede {
  margin-bottom: clamp(24px, 3.5vw, 38px);
}
.page-about .tl-banner {
  margin: 0 0 clamp(22px, 3vw, 34px);
}
.page-about .tl-section .filter-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0 0 clamp(22px, 3vw, 34px);
  padding: 0;
  background: none;
  border: 0;
}
.page-about .tl-list {
  list-style: none;
  margin: 0;
  padding: 0;
  position: relative;
}
.page-about .tl-item {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 10px;
  padding-bottom: clamp(20px, 3vw, 32px);
  border-top: 1px solid var(--line);
  position: relative;
}
.page-about .tl-year {
  display: flex;
  align-items: center;
  gap: 10px;
  padding-top: 18px;
}
.page-about .tl-year .type-data {
  font-size: clamp(18px, 2.4vw, 24px);
  color: var(--cyan);
  letter-spacing: 0.04em;
}
.page-about .tl-dot {
  width: 9px;
  height: 9px;
  flex: none;
  border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 0 4px rgba(61, 240, 196, 0.14);
}
.page-about .tl-body {
  background: var(--panel);
  border: 1px solid var(--line);
  border-left: 2px solid var(--line-accent);
  border-radius: var(--radius);
  padding: clamp(18px, 3vw, 30px);
  transition: border-color var(--dur) var(--ease);
}
.page-about .tl-body:hover {
  border-color: var(--line-accent);
  border-left-color: var(--cyan);
}
.page-about .tl-item:nth-child(even) .tl-body {
  background: var(--cream);
  border-color: rgba(42, 26, 18, 0.16);
  border-left-color: var(--orange);
}
.page-about .tl-item:nth-child(even) .tl-body:hover {
  border-color: rgba(216, 73, 43, 0.5);
  border-left-color: var(--orange);
}
.page-about .tl-item:nth-child(even) .tl-body h3,
.page-about .tl-item:nth-child(even) .tl-body p,
.page-about .tl-item:nth-child(even) .tl-body li,
.page-about .tl-item:nth-child(even) .tl-body summary {
  color: var(--brown);
}
.page-about .tl-item:nth-child(even) .tl-body .type-index {
  color: var(--orange);
}
.page-about .tl-item:nth-child(even) .tl-body .type-data {
  color: rgba(42, 26, 18, 0.55);
}
.page-about .tl-body .type-index {
  margin: 0 0 10px;
}
.page-about .tl-body .type-h3 {
  margin: 0 0 12px;
  font-size: clamp(19px, 2.4vw, 26px);
  line-height: 1.25;
  color: var(--cream);
}
.page-about .tl-body p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.75;
  color: var(--mist);
}

/* 折叠成果清单 */
.page-about .tl-body .fold {
  margin-top: 16px;
  border-top: 1px dashed var(--line-strong);
}
.page-about .tl-item:nth-child(even) .tl-body .fold {
  border-top-color: rgba(42, 26, 18, 0.28);
}
.page-about .tl-body summary {
  cursor: pointer;
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 13px 0 4px;
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--mist);
}
.page-about .tl-body summary::-webkit-details-marker {
  display: none;
}
.page-about .tl-body summary::after {
  content: "+";
  font-family: var(--font-mono);
  font-size: 15px;
  color: var(--cyan);
  line-height: 1;
}
.page-about .tl-item:nth-child(even) .tl-body summary::after {
  color: var(--orange);
}
.page-about .tl-body .fold[open] summary::after {
  content: "–";
}
.page-about .tl-points {
  list-style: none;
  margin: 10px 0 0;
  padding: 0;
  display: grid;
  gap: 8px;
}
.page-about .tl-points li {
  display: grid;
  grid-template-columns: 30px minmax(0, 1fr);
  gap: 10px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--line);
  font-size: 13.5px;
  line-height: 1.65;
  color: var(--muted);
}
.page-about .tl-item:nth-child(even) .tl-points li {
  border-bottom-color: rgba(42, 26, 18, 0.14);
}
.page-about .tl-points .type-data {
  font-size: 12px;
  color: var(--cyan);
  padding-top: 2px;
}

/* ---------- 团队 ---------- */
.page-about .team-side .type-index,
.page-about .team-note .type-index {
  margin: 0 0 10px;
}
.page-about .team-body .type-h1 {
  margin: 0;
  font-size: clamp(24px, 3.8vw, 42px);
  line-height: 1.1;
  letter-spacing: -0.015em;
  color: var(--cream);
}
.page-about .role-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  margin-top: clamp(24px, 3.5vw, 38px);
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}
.page-about .role-card {
  background: linear-gradient(180deg, var(--panel-2) 0%, var(--panel) 100%);
  padding: 22px 20px 26px;
  transition: background var(--dur) var(--ease);
}
.page-about .role-card:hover {
  background: linear-gradient(180deg, rgba(21, 58, 43, 1) 0%, rgba(13, 42, 31, 1) 100%);
}
.page-about .role-card .type-index {
  margin: 0 0 10px;
}
.page-about .role-card .type-h3 {
  margin: 0 0 10px;
  font-size: 17px;
  line-height: 1.35;
  color: var(--cream);
}
.page-about .role-card p {
  margin: 0;
  font-size: 13.5px;
  line-height: 1.7;
  color: var(--muted);
}
.page-about .team-note {
  border-top: 1px solid var(--line);
  padding-top: 16px;
  font-size: 13px;
  line-height: 1.7;
  color: var(--muted);
}
.page-about .team-note p {
  margin: 0;
}

/* ---------- 数据来路 ---------- */
.page-about .flow {
  list-style: none;
  margin: clamp(26px, 3.5vw, 40px) 0 0;
  padding: 0;
  border-top: 1px solid var(--line);
}
.page-about .flow-step {
  display: grid;
  grid-template-columns: 46px minmax(0, 1fr);
  gap: 16px;
  padding: clamp(18px, 2.6vw, 26px) 0;
  border-bottom: 1px solid var(--line);
  transition: background var(--dur) var(--ease);
}
.page-about .flow-num {
  font-size: 15px;
  color: var(--amber);
  padding-top: 3px;
  letter-spacing: 0.06em;
}
.page-about .flow-body .type-h3 {
  margin: 0 0 8px;
  font-size: 17px;
  line-height: 1.3;
  color: var(--cream);
}
.page-about .flow-body p {
  margin: 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--muted);
  max-width: 68ch;
}

/* ---------- 合作生态 ---------- */
.page-about .partners-body .type-h1 {
  margin: 0;
  font-size: clamp(24px, 3.8vw, 42px);
  line-height: 1.1;
  letter-spacing: -0.015em;
  color: var(--cream);
}
.page-about .partner-list {
  list-style: none;
  margin: clamp(22px, 3vw, 32px) 0 0;
  padding: 0;
  display: grid;
  gap: 16px;
}
.page-about .partner-list li {
  padding: 16px 18px;
  border: 1px solid var(--line);
  border-left: 2px solid var(--amber);
  border-radius: var(--radius);
  background: var(--panel);
}
.page-about .partner-list .type-index {
  margin: 0 0 8px;
  color: var(--amber);
}
.page-about .partner-list p {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--mist);
}
.page-about .partners-more {
  margin: 22px 0 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--muted);
}
.page-about .partners-more a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid var(--line-accent);
}
.page-about .partners-more a:hover {
  border-bottom-color: var(--cyan);
}
.page-about .partners-media {
  margin-top: clamp(26px, 4vw, 0px);
}

/* ---------- 版本迭代 ---------- */
.page-about .version-list {
  list-style: none;
  margin: clamp(26px, 3.5vw, 40px) 0 0;
  padding: 0;
  border-top: 1px solid var(--line);
}
.page-about .version-row {
  display: grid;
  grid-template-columns: 1fr;
  gap: 6px;
  padding: clamp(18px, 2.6vw, 24px) 0;
  border-bottom: 1px solid var(--line);
}
.page-about .version-no {
  font-size: 15px;
  letter-spacing: 0.08em;
  color: var(--orange);
}
.page-about .version-row .type-h3 {
  margin: 0;
  font-size: 18px;
  line-height: 1.3;
  color: var(--cream);
}
.page-about .version-row p {
  margin: 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--muted);
}

/* ---------- 内容版图 ---------- */
.page-about .coverage-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  margin-top: clamp(26px, 3.5vw, 40px);
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}
.page-about .coverage-card {
  position: relative;
  background: var(--ink);
  padding: 26px 22px 28px;
  transition: background var(--dur) var(--ease);
}
.page-about .coverage-card:hover {
  background: var(--panel-2);
}
.page-about .coverage-no {
  display: block;
  font-size: 13px;
  letter-spacing: 0.14em;
  color: var(--cyan);
  margin-bottom: 14px;
}
.page-about .coverage-card .type-h3 {
  margin: 0 0 10px;
  font-size: 18px;
  line-height: 1.3;
  color: var(--cream);
}
.page-about .coverage-card p {
  margin: 0;
  font-size: 13.5px;
  line-height: 1.72;
  color: var(--muted);
}
.page-about .coverage-cta {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: clamp(26px, 3.5vw, 38px);
}

/* ---------- 底部行动 ---------- */
.page-about .about-cta {
  border-top: 1px solid var(--line);
}
.page-about .about-cta-inner {
  display: grid;
  gap: 22px;
  align-items: center;
}
.page-about .about-cta-inner .type-h2 {
  margin: 0 0 12px;
  font-size: clamp(22px, 3.5vw, 34px);
  line-height: 1.16;
  letter-spacing: -0.015em;
  color: var(--cream);
}
.page-about .about-cta-inner p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.75;
  color: var(--muted);
  max-width: 56ch;
}
.page-about .about-cta-inner .btn {
  justify-self: start;
  white-space: nowrap;
}

/* ---------- 中屏 ---------- */
@media (min-width: 640px) {
  .page-about .about-facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
  .page-about .role-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .page-about .coverage-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .page-about .version-row {
    grid-template-columns: 64px minmax(0, 1fr);
    gap: 4px 18px;
    align-items: baseline;
  }
  .page-about .version-row .type-h3 {
    grid-column: 2;
  }
  .page-about .version-row p {
    grid-column: 2;
  }
  .page-about .version-no {
    grid-row: 1 / span 2;
    padding-top: 2px;
  }
  .page-about .about-cta-inner {
    grid-template-columns: minmax(0, 1fr) auto;
  }
}

/* ---------- 桌面：时间线轴 ---------- */
@media (min-width: 900px) {
  .page-about {
    --about-axis: 104px;
  }
  .page-about .tl-list::before {
    content: "";
    position: absolute;
    left: var(--about-axis);
    top: 0;
    bottom: 0;
    width: 1px;
    background: linear-gradient(180deg, rgba(61, 240, 196, 0.46) 0%, rgba(61, 240, 196, 0.06) 92%, rgba(61, 240, 196, 0) 100%);
  }
  .page-about .tl-item {
    grid-template-columns: var(--about-axis) minmax(0, 1fr);
    gap: clamp(24px, 3vw, 44px);
    padding-bottom: clamp(24px, 3vw, 36px);
  }
  .page-about .tl-year {
    position: relative;
    flex-direction: column;
    align-items: flex-start;
    gap: 12px;
    padding-top: 24px;
  }
  .page-about .tl-dot {
    position: absolute;
    right: -4.5px;
    top: 30px;
  }
  .page-about .role-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
  .page-about .partners-media {
    margin-top: 0;
  }
  .page-about .coverage-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

/* ---------- 大屏 ---------- */
@media (min-width: 1024px) {
  .page-about .team-note {
    padding-top: 42px;
  }
  .page-about .about-hero .type-display {
    max-width: 15ch;
  }
}