.page-about {
  --about-hair: rgba(143, 163, 186, .16);
  --about-hair-soft: rgba(143, 163, 186, .09);
  --about-panel: linear-gradient(158deg, rgba(22, 35, 61, .94), rgba(11, 20, 36, .68));
  --about-soft: rgba(22, 35, 61, .58);
  --about-sec: clamp(34px, 5vw, 66px);
  color: var(--silver);
  padding-bottom: clamp(44px, 7vw, 96px);
}

.page-about a {
  color: inherit;
}

/* ---------- 面包屑 ---------- */
.page-about .crumbs {
  padding-top: clamp(14px, 2.4vw, 26px);
}

.page-about .crumb-list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin: 0;
  padding: 0;
  list-style: none;
  font-size: .78rem;
  letter-spacing: .09em;
  color: var(--mist);
}

.page-about .crumb-link {
  text-decoration: none;
  color: var(--mist);
  border-bottom: 1px solid transparent;
  transition: color .25s var(--ease), border-color .25s var(--ease);
}

.page-about .crumb-link:hover,
.page-about .crumb-link:focus-visible {
  color: var(--cyan);
  border-bottom-color: var(--cyan);
}

.page-about .crumb-sep {
  color: rgba(143, 163, 186, .45);
}

.page-about .crumb-current {
  color: var(--silver);
  font-weight: 600;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  display: grid;
  gap: clamp(22px, 3.4vw, 40px);
  padding-block: clamp(24px, 4.2vw, 48px) clamp(18px, 3vw, 34px);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  top: -8%;
  right: -14%;
  width: min(600px, 88%);
  height: 440px;
  background:
    radial-gradient(circle at 72% 26%, rgba(53, 240, 208, .13), transparent 62%),
    radial-gradient(circle at 28% 74%, rgba(255, 154, 77, .09), transparent 58%);
  pointer-events: none;
  z-index: 0;
}

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

.page-about .hero-copy h1 {
  margin: 10px 0 18px;
  font-size: clamp(1.9rem, 5.4vw, 3.4rem);
  line-height: 1.13;
  letter-spacing: -.015em;
  font-weight: 800;
  color: var(--silver);
  max-width: 20ch;
}

.page-about .hero-copy .lede {
  max-width: 46ch;
  margin: 0 0 clamp(22px, 3vw, 32px);
}

.page-about .hero-meta {
  display: grid;
  gap: 10px;
  margin: 0;
  grid-template-columns: 1fr;
}

.page-about .meta-cell {
  padding: 14px 16px;
  border: 1px solid var(--about-hair);
  border-radius: var(--r-md);
  background: var(--about-soft);
}

.page-about .meta-cell dt {
  font-size: .74rem;
  letter-spacing: .12em;
  color: var(--mist);
  margin-bottom: 6px;
}

.page-about .meta-cell dd {
  margin: 0;
  font-size: .98rem;
  color: var(--silver);
  font-weight: 600;
}

.page-about .meta-cell .data-num {
  color: var(--cyan);
  font-size: 1.32rem;
  font-weight: 700;
  letter-spacing: .04em;
}

/* 首屏档案卡 */
.page-about .hero-file {
  padding: 14px;
  border: 1px solid var(--about-hair);
  border-radius: var(--r-xl);
  background: var(--about-panel);
  box-shadow: 0 30px 70px -52px var(--cyan-glow);
}

.page-about .hero-file .media-frame {
  border-radius: var(--r-lg);
  overflow: hidden;
}

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

.page-about .file-list {
  list-style: none;
  margin: 14px 0 0;
  padding: 0;
}

.page-about .file-row {
  display: grid;
  gap: 2px;
  padding: 11px 6px;
  border-top: 1px solid var(--about-hair-soft);
}

.page-about .file-row:first-child {
  border-top: 0;
}

.page-about .file-key {
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: .14em;
  color: var(--cyan);
}

.page-about .file-val {
  font-size: .92rem;
  line-height: 1.55;
  color: var(--mist);
}

/* ---------- 通用区块 ---------- */
.page-about .about-sec {
  padding-block: var(--about-sec);
  border-top: 1px solid var(--about-hair-soft);
}

.page-about .about-sec:first-of-type {
  border-top: 0;
}

.page-about .about-head {
  margin-bottom: clamp(18px, 2.6vw, 28px);
}

.page-about .about-head h2 {
  margin: 8px 0 12px;
  font-size: clamp(1.42rem, 3.6vw, 2.2rem);
  line-height: 1.24;
  font-weight: 800;
  letter-spacing: -.01em;
  color: var(--silver);
  max-width: 24ch;
}

.page-about .about-head .prose {
  max-width: 62ch;
  margin: 0;
  color: var(--mist);
  line-height: 1.78;
}

/* ---------- 场景筛选 ---------- */
.page-about .filter-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: clamp(16px, 2.4vw, 24px);
}

.page-about .filter-btn {
  padding: 9px 16px;
  border: 1px solid var(--about-hair);
  border-radius: var(--r-pill);
  background: transparent;
  color: var(--mist);
  font-family: inherit;
  font-size: .84rem;
  letter-spacing: .04em;
  cursor: pointer;
  transition: color .25s var(--ease), border-color .25s var(--ease), background .25s var(--ease);
}

.page-about .filter-btn:hover,
.page-about .filter-btn:focus-visible {
  color: var(--silver);
  border-color: rgba(53, 240, 208, .42);
}

.page-about .filter-btn[aria-pressed="true"] {
  color: var(--void);
  background: var(--cyan);
  border-color: var(--cyan);
  font-weight: 700;
}

.page-about .scene-grid {
  display: grid;
  gap: 14px;
  grid-template-columns: 1fr;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .scene-card {
  position: relative;
  padding: 22px 20px;
  border: 1px solid var(--about-hair);
  border-radius: var(--r-lg);
  background: var(--about-panel);
  overflow: hidden;
  transition: transform .35s var(--ease), border-color .35s var(--ease);
}

.page-about .scene-card::before {
  content: "";
  position: absolute;
  inset: 0 auto auto 0;
  width: 3px;
  height: 100%;
  background: linear-gradient(180deg, var(--cyan), transparent 82%);
  opacity: .55;
}

.page-about .scene-card:hover {
  transform: translateY(-3px);
  border-color: rgba(53, 240, 208, .38);
}

.page-about .scene-card h3 {
  margin: 12px 0 10px;
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--silver);
}

.page-about .scene-card p {
  margin: 0 0 10px;
  font-size: .93rem;
  line-height: 1.75;
  color: var(--mist);
}

.page-about .scene-foot {
  margin: 0;
  font-size: .82rem;
  color: rgba(143, 163, 186, .8);
  padding-top: 10px;
  border-top: 1px dashed var(--about-hair);
}

.page-about .filter-empty {
  margin: 16px 0 0;
  font-size: .88rem;
  color: var(--mist);
}

/* ---------- 双流程 ---------- */
.page-about .flow-grid {
  display: grid;
  gap: clamp(22px, 3.2vw, 36px);
  grid-template-columns: 1fr;
}

.page-about .flow-copy h2 {
  margin: 8px 0 14px;
  font-size: clamp(1.42rem, 3.6vw, 2.15rem);
  line-height: 1.26;
  font-weight: 800;
  color: var(--silver);
  max-width: 24ch;
}

.page-about .flow-copy .prose {
  margin: 0 0 20px;
  max-width: 60ch;
  color: var(--mist);
  line-height: 1.8;
}

.page-about .flow-lanes {
  list-style: none;
  margin: 0 0 18px;
  padding: 0;
  display: grid;
  gap: 12px;
}

.page-about .lane {
  padding: 18px 18px 16px;
  border-radius: var(--r-lg);
  border: 1px solid var(--about-hair);
  background: var(--about-soft);
}

.page-about .lane--data {
  border-left: 3px solid var(--cyan);
}

.page-about .lane--content {
  border-left: 3px solid var(--warm);
}

.page-about .lane p {
  margin: 10px 0 0;
  font-size: .92rem;
  line-height: 1.78;
  color: var(--mist);
}

.page-about .flow-note {
  margin: 0;
  font-size: .86rem;
  color: var(--mist);
}

.page-about .flow-note a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(53, 240, 208, .4);
}

.page-about .flow-note a:hover,
.page-about .flow-note a:focus-visible {
  color: var(--cyan-mist);
  border-bottom-color: var(--cyan-mist);
}

.page-about .flow-media {
  border-radius: var(--r-xl);
  overflow: hidden;
  border: 1px solid var(--about-hair);
  align-self: start;
}

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

/* ---------- 时间线 ---------- */
.page-about .timeline-grid {
  display: grid;
  gap: clamp(20px, 3vw, 34px);
  grid-template-columns: 1fr;
}

.page-about .timeline-media {
  border-radius: var(--r-xl);
  overflow: hidden;
  border: 1px solid var(--about-hair);
}

.page-about .about-timeline {
  position: relative;
  margin: 0;
  padding: 0 0 0 26px;
  list-style: none;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 7px;
  top: 10px;
  bottom: 10px;
  width: 1px;
  background: linear-gradient(180deg, var(--cyan), rgba(143, 163, 186, .18) 72%, transparent);
}

.page-about .tl-item {
  position: relative;
  padding-bottom: 12px;
}

.page-about .tl-item::before {
  content: "";
  position: absolute;
  left: -23px;
  top: 20px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 0 4px rgba(53, 240, 208, .13);
}

.page-about .tl-details > summary {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 6px 12px;
  padding: 14px 16px;
  list-style: none;
  cursor: pointer;
  border: 1px solid var(--about-hair);
  border-radius: var(--r-md);
  background: var(--about-soft);
  transition: border-color .3s var(--ease), background .3s var(--ease);
}

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

.page-about .tl-details > summary:hover,
.page-about .tl-details > summary:focus-visible {
  border-color: rgba(53, 240, 208, .4);
}

.page-about .tl-details[open] > summary {
  border-color: rgba(53, 240, 208, .46);
  background: rgba(22, 35, 61, .86);
}

.page-about .tl-details > summary::after {
  content: "+";
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 1rem;
  color: var(--cyan);
}

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

.page-about .tl-stage {
  font-size: .74rem;
  letter-spacing: .12em;
  color: var(--mist);
}

.page-about .tl-title {
  font-size: 1rem;
  font-weight: 700;
  color: var(--silver);
}

.page-about .tl-version {
  font-family: var(--font-mono);
  font-size: .76rem;
  letter-spacing: .1em;
  color: var(--amber);
  padding: 2px 8px;
  border: 1px solid rgba(255, 196, 107, .34);
  border-radius: var(--r-pill);
}

.page-about .tl-body {
  padding: 12px 16px 4px;
}

.page-about .tl-body p {
  margin: 0;
  font-size: .92rem;
  line-height: 1.8;
  color: var(--mist);
}

/* ---------- 规模 ---------- */
.page-about .stat-grid {
  display: grid;
  gap: 13px;
  grid-template-columns: repeat(auto-fit, minmax(148px, 1fr));
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .stat-card {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 22px 20px 18px;
  border: 1px solid var(--about-hair);
  border-radius: var(--r-lg);
  background: var(--about-panel);
  overflow: hidden;
  transition: transform .35s var(--ease), border-color .35s var(--ease), box-shadow .35s var(--ease);
}

.page-about .stat-card::after {
  content: "";
  position: absolute;
  right: -40%;
  bottom: -70%;
  width: 170px;
  height: 170px;
  background: radial-gradient(circle, var(--cyan-glow), transparent 70%);
  opacity: 0;
  transition: opacity .4s var(--ease);
  pointer-events: none;
}

.page-about .stat-card:hover,
.page-about .stat-card:focus-within {
  transform: translateY(-4px);
  border-color: rgba(53, 240, 208, .42);
  box-shadow: 0 24px 46px -34px var(--cyan-glow);
}

.page-about .stat-card:hover::after,
.page-about .stat-card:focus-within::after {
  opacity: .9;
}

.page-about .stat-num {
  font-family: var(--font-mono);
  font-size: clamp(2rem, 5.6vw, 2.9rem);
  font-weight: 700;
  letter-spacing: .05em;
  line-height: 1;
  color: var(--silver);
}

.page-about .stat-unit {
  font-size: .46em;
  letter-spacing: .06em;
  color: var(--cyan);
  margin-left: 2px;
}

.page-about .stat-label {
  font-size: .84rem;
  line-height: 1.5;
  color: var(--mist);
}

.page-about .stat-tag {
  align-self: flex-start;
  margin-top: 2px;
  opacity: .55;
  transition: opacity .3s var(--ease);
}

.page-about .stat-card:hover .stat-tag,
.page-about .stat-card:focus-within .stat-tag {
  opacity: 1;
}

.page-about .scale-note {
  margin: 18px 0 0;
  max-width: 62ch;
  font-size: .9rem;
  line-height: 1.78;
  color: var(--mist);
}

/* ---------- 生态 ---------- */
.page-about .eco-grid {
  display: grid;
  gap: clamp(20px, 3vw, 34px);
  grid-template-columns: 1fr;
}

.page-about .eco-copy h2 {
  margin: 8px 0 14px;
  font-size: clamp(1.42rem, 3.6vw, 2.15rem);
  line-height: 1.26;
  font-weight: 800;
  color: var(--silver);
  max-width: 22ch;
}

.page-about .eco-copy .prose {
  margin: 0;
  max-width: 58ch;
  color: var(--mist);
  line-height: 1.82;
}

.page-about .eco-cards {
  display: grid;
  gap: 12px;
  grid-template-columns: 1fr;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .eco-card {
  padding: 18px 18px 16px;
  border: 1px solid var(--about-hair);
  border-radius: var(--r-lg);
  background: linear-gradient(150deg, rgba(22, 35, 61, .8), rgba(6, 10, 18, .52));
}

.page-about .eco-card h3 {
  margin: 10px 0 8px;
  font-size: 1rem;
  font-weight: 700;
  color: var(--silver);
  font-family: var(--font-mono);
  letter-spacing: .02em;
}

.page-about .eco-card p {
  margin: 0;
  font-size: .86rem;
  line-height: 1.72;
  color: var(--mist);
}

/* ---------- 服务 ---------- */
.page-about .serve-grid {
  display: grid;
  gap: 12px;
  grid-template-columns: 1fr;
  margin-bottom: clamp(20px, 3vw, 30px);
}

.page-about .serve-card {
  padding: 20px 18px;
  border: 1px solid var(--about-hair);
  border-radius: var(--r-lg);
  background: var(--about-soft);
  border-top: 2px solid rgba(53, 240, 208, .3);
}

.page-about .serve-card h3 {
  margin: 0 0 9px;
  font-size: 1rem;
  font-weight: 700;
  color: var(--silver);
}

.page-about .serve-card p {
  margin: 0;
  font-size: .9rem;
  line-height: 1.78;
  color: var(--mist);
}

.page-about .serve-card a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(53, 240, 208, .38);
}

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

/* ---------- 结尾 CTA ---------- */
.page-about .about-cta {
  display: grid;
  gap: 18px;
  padding: clamp(22px, 4vw, 38px);
  border: 1px solid rgba(53, 240, 208, .26);
  border-radius: var(--r-xl);
  background:
    radial-gradient(circle at 88% 12%, rgba(255, 154, 77, .14), transparent 52%),
    linear-gradient(118deg, rgba(22, 35, 61, .95), rgba(11, 20, 36, .72));
}

.page-about .cta-copy h3 {
  margin: 0 0 10px;
  font-size: clamp(1.15rem, 2.8vw, 1.5rem);
  font-weight: 800;
  color: var(--silver);
}

.page-about .cta-copy p {
  margin: 0;
  max-width: 52ch;
  font-size: .9rem;
  line-height: 1.78;
  color: var(--mist);
  word-break: break-word;
}

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

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

/* ---------- 响应式 ---------- */
@media (min-width: 560px) {
  .page-about .hero-meta {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

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

@media (min-width: 900px) {
  .page-about .about-hero {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    align-items: start;
  }

  .page-about .hero-file {
    margin-top: 26px;
  }

  .page-about .scene-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .flow-grid {
    grid-template-columns: minmax(0, 6fr) minmax(0, 6fr);
    align-items: start;
  }

  .page-about .flow-media {
    margin-top: 40px;
  }

  .page-about .timeline-grid {
    grid-template-columns: minmax(0, 4fr) minmax(0, 8fr);
    align-items: start;
  }

  .page-about .timeline-media {
    margin-top: 18px;
  }

  .page-about .eco-grid {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
    align-items: start;
  }

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

@media (min-width: 1120px) {
  .page-about .stat-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

@media (prefers-reduced-motion: reduce) {
  .page-about .scene-card,
  .page-about .stat-card,
  .page-about .stat-card::after,
  .page-about .stat-tag,
  .page-about .filter-btn,
  .page-about .tl-details > summary {
    transition: none;
  }

  .page-about .scene-card:hover,
  .page-about .stat-card:hover,
  .page-about .stat-card:focus-within {
    transform: none;
  }
}