.page-about {
  --rule-soft: 1px solid rgba(140, 154, 146, 0.24);
  --about-gap: clamp(20px, 3vw, 36px);
}

.page-about .breadcrumb {
  margin: clamp(16px, 2.5vw, 28px) 0 0;
}

.page-about .breadcrumb ol {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0;
  padding: 0;
  list-style: none;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--stone);
}

.page-about .breadcrumb li + li::before {
  content: "/";
  margin-right: 8px;
  color: var(--moss-2);
}

.page-about .breadcrumb a {
  color: var(--stone);
  text-decoration: none;
  border-bottom: 1px solid transparent;
}

.page-about .breadcrumb a:hover,
.page-about .breadcrumb a:focus-visible {
  color: var(--lime);
  border-bottom-color: var(--lime);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding: clamp(22px, 4vw, 44px) 0 clamp(40px, 6vw, 76px);
}

.page-about .about-hero__grid {
  display: grid;
  gap: clamp(28px, 4vw, 56px);
}

@media (min-width: 960px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.12fr) minmax(0, 0.88fr);
    align-items: end;
  }
}

.page-about .about-hero h1 {
  margin: 0.35em 0 0.55em;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(34px, 6.4vw, 66px);
  line-height: 1.02;
  letter-spacing: -0.01em;
  color: var(--paper);
}

.page-about .about-hero h1 em {
  font-style: normal;
  color: var(--lime);
}

.page-about .about-hero .lede {
  max-width: 56ch;
  margin: 0;
  font-size: clamp(15px, 1.6vw, 17px);
  line-height: 1.85;
  color: rgba(237, 232, 218, 0.82);
}

.page-about .hero-stats {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1px;
  margin: clamp(22px, 3vw, 34px) 0 0;
  padding: 0;
  background: var(--moss-2);
  border: 2px solid var(--moss-2);
}

.page-about .hero-stat {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 14px 12px 16px;
  background: var(--moss);
}

.page-about .hero-stat dt {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--stone);
}

.page-about .hero-stat dd {
  margin: 0;
  font-family: var(--font-mono);
  font-size: clamp(18px, 2.8vw, 24px);
  color: var(--paper);
}

.page-about .hero-stat dd .num {
  color: var(--blue);
}

.page-about .hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: clamp(22px, 3vw, 32px);
}

.page-about .hero-visual {
  margin: 0;
}

.page-about .hero-visual__frame {
  position: relative;
  padding: clamp(14px, 2vw, 22px);
  background: var(--moss);
  border: 2px solid var(--moss-2);
  box-shadow: var(--shadow-hard);
  clip-path: polygon(0 0, 100% 0, 100% 88%, 88% 100%, 0 100%);
}

.page-about .hero-visual__frame::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(200, 249, 78, 0.06) 1px, transparent 1px),
    linear-gradient(90deg, rgba(200, 249, 78, 0.06) 1px, transparent 1px);
  background-size: 26px 26px;
  pointer-events: none;
}

.page-about .hero-visual svg {
  display: block;
  position: relative;
  width: 100%;
  height: auto;
}

.page-about .hero-visual figcaption {
  margin-top: 12px;
}

/* ---------- 通用区块标题 ---------- */
.page-about .section .placard {
  margin-bottom: clamp(18px, 2.6vw, 28px);
}

.page-about .sec-title {
  margin: 0 0 clamp(16px, 2.4vw, 24px);
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(25px, 4vw, 42px);
  line-height: 1.08;
  letter-spacing: -0.01em;
  color: var(--paper);
}

.page-about .sub-title {
  margin: clamp(26px, 3.4vw, 38px) 0 12px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(18px, 2.2vw, 22px);
  color: var(--paper);
}

.page-about .prose p {
  margin: 0 0 1.1em;
  font-size: clamp(15px, 1.6vw, 16.5px);
  line-height: 1.85;
  color: rgba(237, 232, 218, 0.8);
}

.page-about .prose p:last-child {
  margin-bottom: 0;
}

.page-about .prose strong {
  color: var(--lime);
  font-weight: 600;
}

.page-about .prose a {
  color: var(--blue);
  text-decoration: none;
  border-bottom: 1px solid rgba(79, 216, 255, 0.5);
}

.page-about .prose a:hover,
.page-about .prose a:focus-visible {
  color: var(--lime);
  border-bottom-color: var(--lime);
}

/* ---------- 起点 ---------- */
.page-about .origin {
  display: grid;
  gap: var(--about-gap);
  padding-top: clamp(32px, 5vw, 56px);
  border-top: var(--rule-soft);
}

@media (min-width: 860px) {
  .page-about .origin {
    grid-template-columns: minmax(0, 0.42fr) minmax(0, 0.58fr);
    align-items: start;
    gap: clamp(32px, 5vw, 72px);
  }
}

.page-about .origin__lead .sec-title {
  margin-bottom: 0;
}

/* ---------- 时间轴 ---------- */
.page-about .timeline-section {
  padding-top: clamp(40px, 6vw, 76px);
}

.page-about .timeline-layout {
  display: grid;
  gap: clamp(18px, 3vw, 34px);
}

@media (min-width: 860px) {
  .page-about .timeline-layout {
    grid-template-columns: 132px minmax(0, 1fr);
    align-items: start;
  }
}

.page-about .year-rail {
  display: flex;
  gap: 8px;
  overflow-x: auto;
  padding-bottom: 6px;
}

@media (min-width: 860px) {
  .page-about .year-rail {
    position: sticky;
    top: 96px;
    flex-direction: column;
    overflow: visible;
    padding: 0 18px 0 0;
    border-right: var(--rule-soft);
  }
}

.page-about .year-tick {
  display: flex;
  align-items: baseline;
  gap: 8px;
  min-height: 44px;
  padding: 10px 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  white-space: nowrap;
  color: var(--stone);
  text-decoration: none;
  border: 2px solid transparent;
  transition: color 0.2s ease, border-color 0.2s ease;
}

.page-about .year-tick .num {
  font-size: 14px;
  color: var(--blue);
}

.page-about .year-tick:hover,
.page-about .year-tick:focus-visible {
  color: var(--paper);
  border-color: var(--moss-2);
}

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

.page-about .tl-item {
  position: relative;
  padding: 0 0 clamp(26px, 4vw, 46px) 32px;
}

.page-about .tl-item::before {
  content: "";
  position: absolute;
  left: 9px;
  top: 18px;
  bottom: 0;
  width: 1px;
  background: linear-gradient(var(--moss-2), rgba(22, 56, 43, 0.2));
}

.page-about .tl-item:last-child::before {
  display: none;
}

.page-about .tl-dot {
  position: absolute;
  left: 0;
  top: 8px;
  width: 19px;
  height: 19px;
  border: 2px solid var(--moss-2);
  background: var(--ink);
}

.page-about .tl-dot::after {
  content: "";
  position: absolute;
  inset: 4px;
  background: var(--blue);
}

.page-about .tl-item:first-child .tl-dot::after {
  background: var(--lime);
}

.page-about .tl-details {
  background: var(--moss);
  border: 2px solid var(--moss-2);
  box-shadow: var(--shadow-hard);
}

.page-about .tl-summary {
  display: flex;
  align-items: baseline;
  gap: 12px;
  min-height: 44px;
  padding: 16px 18px;
  cursor: pointer;
  list-style: none;
}

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

.page-about .tl-summary::after {
  content: "+";
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 22px;
  line-height: 1;
  color: var(--lime);
}

.page-about .tl-details[open] .tl-summary::after {
  content: "−";
}

.page-about .tl-summary:focus-visible {
  outline: 2px solid var(--blue);
  outline-offset: 2px;
}

.page-about .tl-year {
  flex: none;
  font-size: 13px;
  letter-spacing: 0.1em;
  color: var(--clay);
}

.page-about .tl-title {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(16px, 2.2vw, 23px);
  line-height: 1.28;
  color: var(--paper);
}

.page-about .tl-body {
  padding: 0 18px 20px;
}

.page-about .tl-body p {
  margin: 0 0 0.9em;
  font-size: 15px;
  line-height: 1.8;
  color: rgba(237, 232, 218, 0.78);
}

.page-about .tl-body p:last-child {
  margin-bottom: 0;
}

/* ---------- 团队 ---------- */
.page-about .team-section {
  padding-top: clamp(40px, 6vw, 76px);
  border-top: var(--rule-soft);
}

.page-about .team-media {
  margin: 0 0 clamp(20px, 3vw, 30px);
  border: 2px solid var(--moss-2);
  box-shadow: var(--shadow-hard);
}

.page-about .team-media img,
.page-about .flow-media img,
.page-about .project-media img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
}

.page-about .team-media img {
  aspect-ratio: 3 / 2;
}

.page-about .team-grid {
  display: grid;
  gap: 1px;
  background: var(--moss-2);
  border: 2px solid var(--moss-2);
}

@media (min-width: 760px) {
  .page-about .team-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

.page-about .team-card {
  padding: clamp(18px, 2.4vw, 26px);
  background: var(--moss);
  transition: background 0.2s ease;
}

.page-about .team-card:hover,
.page-about .team-card:focus-within,
.page-about .team-card:focus {
  background: var(--moss-2);
  outline: none;
}

.page-about .team-num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(28px, 4vw, 40px);
  line-height: 1;
  color: var(--lime);
}

.page-about .team-card h3 {
  margin: 12px 0 8px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 18px;
  color: var(--paper);
}

.page-about .team-card p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.75;
  color: rgba(237, 232, 218, 0.74);
}

.page-about .team-card a {
  color: var(--blue);
  text-decoration: none;
  border-bottom: 1px solid rgba(79, 216, 255, 0.5);
}

.page-about .team-card a:hover,
.page-about .team-card a:focus-visible {
  color: var(--lime);
  border-bottom-color: var(--lime);
}

.page-about .team-detail {
  margin-top: 12px;
  padding-top: 12px;
  border-top: var(--rule-soft);
}

@media (hover: hover) and (min-width: 760px) {
  .page-about .team-detail {
    max-height: 0;
    overflow: hidden;
    opacity: 0;
    padding-top: 0;
    margin-top: 0;
    border-top-color: transparent;
    transition: max-height 0.3s ease, opacity 0.3s ease, margin-top 0.3s ease,
      padding-top 0.3s ease;
  }

  .page-about .team-card:hover .team-detail,
  .page-about .team-card:focus-within .team-detail,
  .page-about .team-card:focus .team-detail {
    max-height: 220px;
    opacity: 1;
    margin-top: 12px;
    padding-top: 12px;
    border-top-color: rgba(140, 154, 146, 0.24);
  }
}

.page-about .team-detail p {
  font-size: 13.5px;
  line-height: 1.75;
  color: rgba(237, 232, 218, 0.66);
}

/* ---------- 流程 ---------- */
.page-about .flow-section {
  padding-top: clamp(40px, 6vw, 76px);
  border-top: var(--rule-soft);
}

.page-about .flow {
  display: grid;
  gap: 1px;
  margin: 0;
  padding: 0;
  list-style: none;
  background: var(--moss-2);
  border: 2px solid var(--moss-2);
}

@media (min-width: 800px) {
  .page-about .flow {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

.page-about .flow li {
  padding: 18px 18px 22px;
  background: var(--moss);
}

.page-about .flow-step {
  display: block;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.14em;
  color: var(--clay);
}

.page-about .flow h3 {
  margin: 10px 0 8px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(17px, 2vw, 20px);
  color: var(--paper);
}

.page-about .flow p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.78;
  color: rgba(237, 232, 218, 0.76);
}

.page-about .flow-explain {
  max-width: 72ch;
  margin-top: clamp(22px, 3vw, 32px);
}

.page-about .flow-media {
  margin: clamp(24px, 3.4vw, 38px) 0 0;
  border: 2px solid var(--moss-2);
  box-shadow: var(--shadow-hard);
}

.page-about .flow-media img {
  aspect-ratio: 12 / 7;
  clip-path: polygon(0 0, 100% 0, 100% 100%, 6% 100%);
}

.page-about .flow-media figcaption {
  padding: 10px 14px 12px;
}

/* ---------- 项目与合作 ---------- */
.page-about .project-section {
  padding-top: clamp(40px, 6vw, 76px);
  border-top: var(--rule-soft);
}

.page-about .project-layout {
  display: grid;
  gap: clamp(26px, 4vw, 48px);
}

@media (min-width: 900px) {
  .page-about .project-layout {
    grid-template-columns: minmax(0, 1.08fr) minmax(0, 0.92fr);
    align-items: start;
  }
}

.page-about .project-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: clamp(20px, 2.6vw, 28px) 0 0;
  padding: 0;
  list-style: none;
}

.page-about .project-tags li {
  padding: 8px 12px;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.04em;
  color: var(--paper);
  background: var(--moss);
  border: 2px solid var(--moss-2);
}

.page-about .project-tags li:nth-child(3n + 2) {
  color: var(--blue);
  border-color: rgba(79, 216, 255, 0.42);
}

.page-about .project-tags li:nth-child(4n) {
  color: var(--lime);
  border-color: rgba(200, 249, 78, 0.4);
}

.page-about .partner-list {
  display: grid;
  gap: 12px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .partner-list li {
  display: grid;
  grid-template-columns: 44px minmax(0, 1fr);
  gap: 12px;
  padding-bottom: 12px;
  border-bottom: var(--rule-soft);
  font-size: 14.5px;
  line-height: 1.78;
  color: rgba(237, 232, 218, 0.78);
}

.page-about .partner-list li:last-child {
  border-bottom: none;
  padding-bottom: 0;
}

.page-about .partner-list .num {
  font-family: var(--font-mono);
  font-size: 20px;
  line-height: 1.3;
  color: var(--blue);
}

.page-about .project-media {
  margin: 0;
  border: 2px solid var(--moss-2);
  box-shadow: var(--shadow-hard);
}

.page-about .project-media img {
  aspect-ratio: 1 / 1;
}

.page-about .project-media figcaption {
  padding: 10px 14px 12px;
}

/* ---------- 后续方向 ---------- */
.page-about .roadmap-section {
  padding-top: clamp(40px, 6vw, 76px);
  border-top: var(--rule-soft);
}

.page-about .roadmap {
  display: grid;
  gap: clamp(20px, 3vw, 30px);
}

@media (min-width: 760px) {
  .page-about .roadmap {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

.page-about .roadmap article {
  padding-top: 14px;
  border-top: 2px solid var(--lime);
}

.page-about .roadmap-no {
  display: block;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--clay);
}

.page-about .roadmap h3 {
  margin: 10px 0 8px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(17px, 2vw, 21px);
  color: var(--paper);
}

.page-about .roadmap p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: rgba(237, 232, 218, 0.76);
}

/* ---------- 收尾面板 ---------- */
.page-about .closing {
  margin-top: clamp(34px, 5vw, 60px);
  padding: clamp(22px, 3.4vw, 38px);
}

.page-about .closing h2 {
  margin: 8px 0 10px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(22px, 3.2vw, 32px);
  line-height: 1.15;
  color: var(--paper);
}

.page-about .closing p {
  max-width: 62ch;
  margin: 0;
  font-size: 15px;
  line-height: 1.8;
  color: rgba(237, 232, 218, 0.78);
}

.page-about .closing .hero-actions {
  margin-top: clamp(18px, 2.6vw, 26px);
}

@media (prefers-reduced-motion: reduce) {
  .page-about .team-card,
  .page-about .team-detail,
  .page-about .year-tick {
    transition: none;
  }

  .page-about .team-detail {
    max-height: none;
    opacity: 1;
    margin-top: 12px;
    padding-top: 12px;
    border-top-color: rgba(140, 154, 146, 0.24);
  }
}