.page-about {
  --about-hero-pad: 150px;
  --about-aside-w: 260px;
  background: var(--sand-gray);
}

/* ===== Hero 首屏 ===== */
.page-about .about-hero {
  background: var(--charcoal);
  padding: var(--about-hero-pad) 0 72px;
  position: relative;
  overflow: hidden;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  top: -30%;
  right: -18%;
  width: 56%;
  height: 150%;
  background: var(--terracotta);
  transform: skewX(-20deg);
  z-index: 0;
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  top: 0;
  right: 6%;
  width: 26%;
  height: 100%;
  background: linear-gradient(160deg, var(--sand-gray), transparent 78%);
  opacity: 0.24;
  transform: skewX(-20deg);
  z-index: 0;
}

.page-about .about-hero-container {
  position: relative;
  z-index: 2;
}

.page-about .about-hero .breadcrumb {
  margin-bottom: 40px;
}

.page-about .about-hero .breadcrumb a {
  color: rgba(245, 240, 230, 0.66);
  text-decoration: none;
}

.page-about .about-hero .breadcrumb [aria-current="page"] {
  color: var(--vital-orange);
}

.page-about .about-hero-row {
  display: grid;
  grid-template-columns: 1fr;
  gap: 24px;
  align-items: center;
}

.page-about .about-hero-copy {
  position: relative;
  z-index: 2;
  max-width: 680px;
}

.page-about .about-hero-copy .eyebrow {
  color: var(--vital-orange);
  margin-bottom: 14px;
}

.page-about .about-hero h1 {
  margin: 0 0 20px;
  font-family: var(--font-black);
  font-weight: 900;
  font-size: clamp(34px, 4.6vw, 56px);
  line-height: 1.16;
  letter-spacing: 0.01em;
}

.page-about .about-hero h1 span:first-child {
  display: block;
  font-size: 0.56em;
  color: var(--cream);
  opacity: 0.72;
  margin-bottom: 0.28em;
}

.page-about .about-hero h1 span:last-child {
  display: block;
  color: var(--vital-orange);
}

.page-about .about-hero-lead {
  font-family: var(--font-light);
  font-size: 16px;
  line-height: 1.75;
  color: var(--cream);
  opacity: 0.88;
  margin: 0 0 32px;
  max-width: 600px;
}

.page-about .about-hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
}

.page-about .about-hero-actions .btn-outline {
  color: var(--cream);
  border-color: rgba(245, 240, 230, 0.5);
}

.page-about .about-hero-art {
  position: relative;
  min-height: 300px;
  display: none;
}

.page-about .hero-slab {
  position: absolute;
}

.page-about .hero-slab--terracotta {
  right: 4%;
  top: 30%;
  width: 250px;
  height: 170px;
  background: var(--terracotta);
  transform: skewX(-18deg);
  z-index: 2;
  box-shadow: var(--shadow);
}

.page-about .hero-slab--sand {
  right: 22%;
  top: 8%;
  width: 170px;
  height: 210px;
  background: var(--sand-gray);
  transform: skewX(-18deg);
  opacity: 0.5;
  z-index: 1;
}

.page-about .hero-ring {
  position: absolute;
  right: -14%;
  bottom: -10%;
  width: 260px;
  height: 260px;
  border: 28px solid var(--moss-green);
  border-radius: 50%;
  opacity: 0.3;
  z-index: 0;
}

.page-about .hero-tag {
  position: absolute;
  left: 8%;
  bottom: 8%;
  z-index: 3;
  background: var(--electric-blue);
  color: var(--cream);
  font-family: var(--font-black);
  font-size: 13px;
  letter-spacing: 0.12em;
  padding: 10px 16px;
  transform: skewX(-12deg);
}

/* ===== 档案展区 ===== */
.page-about .about-archive {
  background: var(--sand-gray);
  padding: 56px 0 24px;
  position: relative;
}

.page-about .about-archive::before {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--vital-orange) 0%, var(--terracotta) 45%, var(--sand-gray) 45%, var(--electric-blue) 100%);
}

.page-about .about-archive-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 44px;
}

.page-about .archive-aside-inner {
  padding: 24px 20px;
  background: var(--charcoal);
  clip-path: polygon(0 0, calc(100% - 18px) 0, 100% 18px, 100% 100%, 0 100%);
  color: var(--cream);
}

.page-about .archive-kicker {
  font-family: var(--font-black);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--vital-orange);
  margin: 0 0 6px;
}

.page-about .archive-title {
  font-family: var(--font-black);
  font-size: 24px;
  margin: 0 0 20px;
  color: var(--cream);
  border-bottom: 1px solid rgba(245, 240, 230, 0.18);
  padding-bottom: 14px;
}

.page-about .archive-nav {
  display: flex;
  flex-direction: column;
  gap: 2px;
  margin-bottom: 20px;
}

.page-about .archive-nav a {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 10px 10px 10px 0;
  color: var(--cream);
  text-decoration: none;
  font-family: var(--font-body);
  font-size: 15px;
  border-bottom: 1px solid rgba(245, 240, 230, 0.1);
  transition: color var(--duration) var(--ease-out), padding-left var(--duration) var(--ease-out);
}

.page-about .archive-nav a span {
  font-family: var(--font-black);
  font-size: 12px;
  color: var(--vital-orange);
}

.page-about .archive-nav a:hover,
.page-about .archive-nav a:focus-visible {
  color: var(--vital-orange);
  padding-left: 8px;
  outline: none;
}

.page-about .archive-aside-card {
  background: var(--terracotta);
  padding: 16px 18px;
  clip-path: polygon(0 0, calc(100% - 12px) 0, 100% 12px, 100% 100%, 0 100%);
  display: flex;
  flex-direction: column;
  gap: 4px;
  margin-bottom: 16px;
}

.page-about .archive-aside-card span {
  font-size: 12px;
  letter-spacing: 0.08em;
  opacity: 0.82;
}

.page-about .archive-aside-card strong {
  font-family: var(--font-black);
  font-size: 16px;
  color: var(--cream);
}

.page-about .archive-aside-card em {
  font-style: normal;
  font-size: 13px;
  color: var(--cream);
  opacity: 0.78;
}

.page-about .archive-aside-note {
  font-size: 13px;
  line-height: 1.6;
  color: rgba(245, 240, 230, 0.72);
  margin: 0;
  padding-top: 12px;
  border-top: 1px dashed rgba(245, 240, 230, 0.18);
}

.page-about .archive-main {
  min-width: 0;
}

.page-about .archive-section {
  margin-bottom: 72px;
  scroll-margin-top: 96px;
}

/* ===== Section Head ===== */
.page-about .section-head {
  position: relative;
  margin-bottom: 28px;
  padding-left: 16px;
  border-left: 4px solid var(--vital-orange);
}

.page-about .section-title {
  margin: 8px 0 10px;
  font-family: var(--font-black);
  font-size: clamp(26px, 3vw, 36px);
  line-height: 1.2;
}

.page-about .section-desc {
  margin: 0;
  font-size: 15px;
  line-height: 1.7;
}

/* ===== 发展历程 ===== */
.page-about .milestone-layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: 24px;
}

.page-about .milestone-figure {
  margin: 0;
}

.page-about .milestone-img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  clip-path: polygon(0 0, calc(100% - 20px) 0, 100% 20px, 100% 100%, 12px 100%, 0 calc(100% - 12px));
}

.page-about .milestone-figure figcaption {
  font-size: 12px;
  margin-top: 8px;
  color: rgba(43, 43, 43, 0.6);
  letter-spacing: 0.06em;
}

.page-about .milestone-board {
  min-width: 0;
}

.page-about .milestone-timeline {
  position: relative;
  padding: 8px 0;
}

.page-about .timeline-svg {
  position: absolute;
  right: 0;
  top: 0;
  width: 62%;
  height: 100%;
  pointer-events: none;
  z-index: 0;
  opacity: 0.75;
}

.page-about .milestone-item {
  position: relative;
  padding: 0 0 0 48px;
  margin-bottom: 14px;
  z-index: 2;
}

.page-about .milestone-item::before {
  content: "";
  position: absolute;
  left: 8px;
  top: 18px;
  width: 15px;
  height: 15px;
  border-radius: 50%;
  background: var(--vital-orange);
  border: 3px solid var(--cream);
  box-shadow: 0 0 0 2px var(--vital-orange);
  z-index: 2;
}

.page-about .milestone-item summary {
  list-style: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 14px 16px;
  background: var(--cream);
  border-left: 4px solid var(--vital-orange);
  font-family: var(--font-black);
  font-size: 16px;
  color: var(--charcoal);
  transition: background var(--duration) var(--ease-out), color var(--duration) var(--ease-out), border-color var(--duration) var(--ease-out);
}

.page-about .milestone-item summary::-webkit-details-marker {
  display: none;
}

.page-about .milestone-item summary::after {
  content: "+";
  margin-left: auto;
  font-size: 20px;
  font-weight: 900;
  color: var(--vital-orange);
}

.page-about .milestone-item[open] summary {
  background: var(--terracotta);
  border-left-color: var(--terracotta);
  color: var(--cream);
}

.page-about .milestone-item[open] summary::after {
  content: "−";
  color: var(--cream);
}

.page-about .milestone-item summary:hover,
.page-about .milestone-item summary:focus-visible {
  background: var(--light-sand);
  color: var(--charcoal);
  outline: none;
}

.page-about .milestone-item[open] summary:hover {
  background: var(--terracotta);
  color: var(--cream);
}

.page-about .milestone-year {
  font-size: 22px;
  letter-spacing: 0.02em;
  min-width: 58px;
}

.page-about .milestone-title {
  font-size: 15px;
  opacity: 0.78;
}

.page-about .milestone-item[open] .milestone-title {
  opacity: 0.9;
}

.page-about .milestone-body {
  padding: 14px 16px 16px;
  background: rgba(245, 240, 230, 0.55);
  border-left: 3px solid var(--electric-blue);
  margin: 0 0 10px;
}

.page-about .milestone-body p {
  margin: 0 0 10px;
  font-size: 14px;
  line-height: 1.7;
}

.page-about .milestone-body ul {
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .milestone-body li {
  position: relative;
  padding: 6px 0 6px 18px;
  font-size: 13px;
  line-height: 1.6;
  border-top: 1px dashed var(--light-sand);
}

.page-about .milestone-body li::before {
  content: "▸";
  position: absolute;
  left: 0;
  color: var(--electric-blue);
  font-weight: 900;
}

/* ===== 数据服务能力 ===== */
.page-about .capability-flow {
  display: flex;
  flex-direction: column;
  gap: 6px;
  align-items: stretch;
  margin-bottom: 28px;
  padding: 16px;
  background: var(--charcoal);
  clip-path: polygon(0 0, calc(100% - 16px) 0, 100% 16px, 100% 100%, 0 100%);
}

.page-about .flow-step {
  flex: 0 1 auto;
  min-width: 90px;
  text-align: center;
  padding: 10px 12px;
  background: var(--cream);
  color: var(--charcoal);
  font-family: var(--font-black);
  font-size: 13px;
  clip-path: polygon(0 0, calc(100% - 10px) 0, 100% 10px, 100% 100%, 0 100%);
}

.page-about .flow-step:first-child {
  background: var(--vital-orange);
  color: var(--cream);
}

.page-about .flow-step:last-child {
  background: var(--terracotta);
  color: var(--cream);
}

.page-about .flow-arrow {
  align-self: center;
  color: var(--vital-orange);
  font-size: 18px;
  font-weight: 900;
  transform: rotate(90deg);
  line-height: 1;
}

.page-about .capability-metrics {
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
  margin-bottom: 28px;
}

.page-about .metric-card {
  position: relative;
  background: var(--cream);
  padding: 20px 18px 16px;
  clip-path: polygon(0 0, calc(100% - 14px) 0, 100% 14px, 100% 100%, 0 100%);
  border-bottom: 3px solid var(--vital-orange);
  min-height: 120px;
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.page-about .metric-num {
  font-family: var(--font-black);
  font-size: 32px;
  line-height: 1.05;
  color: var(--charcoal);
}

.page-about .metric-label {
  font-family: var(--font-black);
  font-size: 14px;
  color: var(--terracotta);
}

.page-about .metric-hint {
  margin: 8px 0 0;
  font-size: 12px;
  line-height: 1.55;
  color: rgba(43, 43, 43, 0.72);
  border-top: 1px dashed var(--light-sand);
  padding-top: 8px;
}

.page-about .capability-detail {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
  margin-bottom: 28px;
}

.page-about .capability-detail h3 {
  font-family: var(--font-black);
  font-size: 17px;
  margin: 0 0 8px;
}

.page-about .capability-detail p {
  font-size: 14px;
  line-height: 1.7;
  margin: 0;
}

.page-about .capability-tags {
  background: var(--charcoal);
  color: var(--cream);
  padding: 24px 22px;
  clip-path: polygon(0 0, calc(100% - 22px) 0, 100% 22px, 100% 100%, 22px 100%, 0 calc(100% - 22px));
}

.page-about .capability-tags h3 {
  font-family: var(--font-black);
  font-size: 19px;
  margin: 0 0 8px;
}

.page-about .capability-tags p {
  font-size: 14px;
  line-height: 1.7;
  color: rgba(245, 240, 230, 0.78);
  margin: 0 0 16px;
  max-width: 640px;
}

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

.page-about .tag-chip {
  background: var(--cream);
  color: var(--charcoal);
  font-family: var(--font-black);
  padding: 8px 14px;
  font-size: 13px;
  clip-path: polygon(0 0, calc(100% - 8px) 0, 100% 8px, 100% 100%, 0 100%);
}

.page-about .tag-chip:nth-child(odd) {
  background: var(--vital-orange);
  color: var(--cream);
}

.page-about .tag-chip:nth-child(even) {
  background: var(--electric-blue);
  color: var(--cream);
}

.page-about .capability-figure {
  margin: 0 0 72px;
}

.page-about .capability-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  clip-path: polygon(0 0, calc(100% - 28px) 0, 100% 28px, 100% 100%, 0 100%);
}

/* ===== 资质认证与合作生态 ===== */
.page-about .ecosystem-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
}

.page-about .ecosystem-license {
  background: var(--moss-green);
  color: var(--cream);
  padding: 26px 24px;
  clip-path: polygon(0 0, calc(100% - 18px) 0, 100% 18px, 100% 100%, 0 100%);
}

.page-about .license-badge {
  display: inline-block;
  background: var(--charcoal);
  color: var(--cream);
  font-family: var(--font-black);
  font-size: 12px;
  letter-spacing: 0.14em;
  padding: 6px 12px;
  margin-bottom: 14px;
  transform: skewX(-10deg);
}

.page-about .ecosystem-license h3 {
  font-family: var(--font-black);
  font-size: 18px;
  margin: 0 0 8px;
}

.page-about .ecosystem-license p {
  font-size: 14px;
  line-height: 1.7;
  margin: 0;
  opacity: 0.92;
}

.page-about .ecosystem-partners {
  background: var(--cream);
  padding: 26px 24px;
  clip-path: polygon(0 0, calc(100% - 18px) 0, 100% 18px, 100% 100%, 0 100%);
}

.page-about .ecosystem-partners h3 {
  font-family: var(--font-black);
  font-size: 18px;
  margin: 0 0 8px;
}

.page-about .ecosystem-partners p {
  font-size: 14px;
  line-height: 1.7;
  margin: 0 0 12px;
}

.page-about .ecosystem-partners ul {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .ecosystem-partners li {
  padding: 8px 0 8px 20px;
  position: relative;
  font-size: 14px;
  line-height: 1.55;
  border-top: 1px dashed var(--light-sand);
}

.page-about .ecosystem-partners li::before {
  content: "▸";
  position: absolute;
  left: 0;
  color: var(--electric-blue);
  font-weight: 900;
}

/* ===== 团队与组织形态 ===== */
.page-about .team-roles {
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
  margin-bottom: 28px;
}

.page-about .role-card {
  background: var(--cream);
  padding: 22px 20px 18px;
  clip-path: polygon(0 0, calc(100% - 14px) 0, 100% 14px, 100% 100%, 0 100%);
  border-top: 4px solid var(--terracotta);
}

.page-about .role-card:nth-child(2) {
  border-top-color: var(--electric-blue);
}

.page-about .role-card:nth-child(3) {
  border-top-color: var(--moss-green);
}

.page-about .role-num {
  font-family: var(--font-black);
  font-size: 12px;
  color: var(--vital-orange);
  letter-spacing: 0.16em;
}

.page-about .role-card h3 {
  font-family: var(--font-black);
  font-size: 17px;
  margin: 6px 0 8px;
}

.page-about .role-card p {
  font-size: 13px;
  line-height: 1.66;
  margin: 0;
}

.page-about .team-figure {
  margin: 0 0 28px;
}

.page-about .team-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  clip-path: polygon(0 0, calc(100% - 32px) 0, 100% 32px, 100% 100%, 0 100%);
}

.page-about .team-contact-note {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
  background: var(--charcoal);
  color: var(--cream);
  padding: 22px;
  clip-path: polygon(0 0, calc(100% - 18px) 0, 100% 18px, 100% 100%, 0 100%);
}

.page-about .team-contact-note p {
  font-size: 14px;
  line-height: 1.8;
  margin: 0;
  color: rgba(245, 240, 230, 0.85);
}

.page-about .team-contact-note a {
  color: var(--vital-orange);
  text-decoration: none;
  border-bottom: 1px solid rgba(242, 122, 36, 0.4);
}

.page-about .team-contact-note a:hover {
  color: var(--cream);
}

/* ===== 底部互链 ===== */
.page-about .about-next {
  background: var(--sand-gray);
  padding: 16px 0 80px;
}

.page-about .about-next-panel {
  background: var(--charcoal);
  color: var(--cream);
  padding: 40px 28px;
  display: grid;
  grid-template-columns: 1fr;
  gap: 24px;
  position: relative;
  overflow: hidden;
}

.page-about .about-next-panel::after {
  content: "";
  position: absolute;
  right: -40px;
  top: -40px;
  width: 180px;
  height: 180px;
  background: var(--terracotta);
  transform: rotate(18deg);
  opacity: 0.7;
  z-index: 0;
}

.page-about .next-copy {
  position: relative;
  z-index: 2;
}

.page-about .next-copy h2 {
  font-family: var(--font-black);
  font-size: clamp(24px, 3vw, 34px);
  margin: 0 0 12px;
}

.page-about .next-copy p {
  margin: 0;
  font-size: 15px;
  line-height: 1.7;
  color: rgba(245, 240, 230, 0.78);
  max-width: 480px;
}

.page-about .next-links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  position: relative;
  z-index: 2;
}

.page-about .next-links .btn-outline {
  color: var(--cream);
  border-color: rgba(245, 240, 230, 0.5);
}

/* ===== 响应式增强 ===== */
@media (min-width: 640px) {
  .page-about .capability-metrics {
    grid-template-columns: repeat(2, 1fr);
  }

  .page-about .capability-flow {
    flex-direction: row;
    flex-wrap: wrap;
  }

  .page-about .flow-step {
    flex: 1 1 0;
  }

  .page-about .flow-arrow {
    transform: none;
  }
}

@media (min-width: 768px) {
  .page-about .milestone-layout {
    grid-template-columns: 220px 1fr;
    gap: 28px;
    align-items: stretch;
  }

  .page-about .milestone-figure {
    position: relative;
    overflow: hidden;
  }

  .page-about .milestone-img {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
  }

  .page-about .capability-detail {
    grid-template-columns: 1fr 1fr;
  }

  .page-about .ecosystem-grid {
    grid-template-columns: 1fr 1fr;
  }

  .page-about .team-roles {
    grid-template-columns: repeat(3, 1fr);
  }

  .page-about .team-contact-note {
    grid-template-columns: 1fr 1fr;
  }

  .page-about .about-next-panel {
    grid-template-columns: 1.2fr 1fr;
    align-items: center;
  }
}

@media (min-width: 992px) {
  .page-about .about-hero-row {
    grid-template-columns: 1.1fr 0.9fr;
  }

  .page-about .about-hero-art {
    display: block;
  }

  .page-about .about-archive-grid {
    grid-template-columns: var(--about-aside-w) 1fr;
    gap: 56px;
    align-items: start;
  }

  .page-about .archive-aside {
    position: sticky;
    top: 96px;
  }

  .page-about .capability-metrics {
    grid-template-columns: repeat(4, 1fr);
  }
}

@media (hover: hover) and (min-width: 992px) {
  .page-about .metric-hint {
    max-height: 0;
    opacity: 0;
    overflow: hidden;
    padding-top: 0;
    border-top: none;
    transition: max-height var(--duration) var(--ease-out), opacity var(--duration) var(--ease-out), padding-top var(--duration) var(--ease-out);
  }

  .page-about .metric-card:hover .metric-hint,
  .page-about .metric-card:focus-within .metric-hint {
    max-height: 80px;
    opacity: 1;
    padding-top: 8px;
    border-top: 1px dashed var(--light-sand);
  }
}