.page-about {
  --about-rail: 216px;
  --about-cut: 22px;
  --about-gap: 36px;
  --about-sec: 64px;
  display: block;
  background: var(--c-night);
  color: var(--c-white);
}

@media (min-width: 768px) {
  .page-about {
    --about-gap: 48px;
    --about-sec: 88px;
  }
}

@media (min-width: 1200px) {
  .page-about {
    --about-sec: 104px;
  }
}

/* ---------- 面包屑 ---------- */
.page-about .about-crumb {
  padding: 22px 0 0;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 32px;
  align-items: end;
  padding: 24px 0 60px;
}

@media (min-width: 900px) {
  .page-about .about-hero {
    grid-template-columns: minmax(0, 6fr) minmax(0, 6fr);
    gap: 56px;
    padding: 38px 0 88px;
  }
}

.page-about .about-hero-copy {
  min-width: 0;
}

.page-about .about-hero h1 {
  margin: 14px 0 20px;
  font-family: var(--font-sans);
  font-size: clamp(2.2rem, 7.6vw, 4.4rem);
  font-weight: 900;
  line-height: 1.04;
  letter-spacing: -0.02em;
  color: var(--c-white);
}

.page-about .about-hero .lead {
  margin: 0;
  max-width: 46ch;
  font-size: 1.04rem;
  line-height: 1.78;
  color: var(--c-mist);
}

.page-about .hero-stats {
  display: flex;
  flex-wrap: wrap;
  gap: 20px 52px;
  margin: 34px 0 0;
  padding: 26px 0 0;
  list-style: none;
  border-top: 1px solid var(--c-iron);
}

.page-about .hero-stats li {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.page-about .hero-stats .num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(1.6rem, 4.2vw, 2.1rem);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--c-gold-hi);
}

.page-about .hero-stat-label {
  font-size: 0.8rem;
  letter-spacing: 0.08em;
  color: var(--c-mist);
}

.page-about .about-hero-media {
  position: relative;
  margin: 0;
  min-width: 0;
}

.page-about .about-hero-media img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - var(--about-cut)), calc(100% - var(--about-cut)) 100%, 0 100%);
}

/* ---------- 主体布局 ---------- */
.page-about .about-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--about-gap);
  padding-bottom: 72px;
}

@media (min-width: 1024px) {
  .page-about .about-layout {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    gap: 72px;
    padding-bottom: 104px;
  }
}

/* ---------- 左侧脉络栏 ---------- */
.page-about .about-rail {
  min-width: 0;
}

.page-about .about-rail .eyebrow {
  margin: 0 0 16px;
  color: var(--c-gold);
}

.page-about .rail-list {
  position: relative;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .rail-item {
  min-width: 0;
}

.page-about .rail-link {
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
  padding: 6px 11px;
  font-size: 0.85rem;
  color: var(--c-mist);
  text-decoration: none;
  background: var(--c-deep);
  border: 1px solid var(--c-iron);
  transition: color var(--dur-fast) var(--ease), border-color var(--dur-fast) var(--ease);
}

.page-about .rail-link:hover {
  color: var(--c-white);
  border-color: var(--c-gold);
}

.page-about .rail-num {
  font-size: 0.76rem;
  color: var(--c-gold);
  letter-spacing: 0.06em;
}

.page-about .rail-item.is-current .rail-link {
  color: var(--c-white);
  border-color: var(--c-gold);
}

@media (min-width: 1024px) {
  .page-about .about-rail {
    position: sticky;
    top: calc(var(--header-h) + 30px);
    align-self: start;
  }

  .page-about .rail-list {
    flex-direction: column;
    flex-wrap: nowrap;
    gap: 2px;
    padding-left: 24px;
  }

  .page-about .rail-list::before {
    content: "";
    position: absolute;
    left: 5px;
    top: 14px;
    bottom: 14px;
    width: 1px;
    background: var(--c-iron);
  }

  .page-about .rail-item {
    position: relative;
  }

  .page-about .rail-item::before {
    content: "";
    position: absolute;
    left: -24px;
    top: 14px;
    width: 9px;
    height: 9px;
    background: var(--c-iron);
    transition: background var(--dur-fast) var(--ease);
  }

  .page-about .rail-item.is-current::before {
    background: var(--c-gold);
  }

  .page-about .rail-link {
    padding: 9px 4px;
    background: none;
    border: 0;
  }

  .page-about .rail-item.is-current .rail-link {
    border-color: transparent;
    color: var(--c-white);
  }
}

/* ---------- 叙事流 ---------- */
.page-about .about-flow {
  display: flex;
  flex-direction: column;
  gap: var(--about-sec);
  min-width: 0;
}

.page-about .flow-block {
  min-width: 0;
  scroll-margin-top: calc(var(--header-h) + 28px);
}

.page-about .flow-eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  margin: 0 0 14px;
  font-size: 0.76rem;
  letter-spacing: 0.18em;
  color: var(--c-mist);
}

.page-about .flow-eyebrow .mono {
  font-size: 0.82rem;
  letter-spacing: 0.05em;
  color: var(--c-gold);
}

.page-about .flow-block h2,
.page-about .about-cta h2 {
  margin: 0 0 18px;
  font-family: var(--font-sans);
  font-size: clamp(1.55rem, 3.6vw, 2.4rem);
  font-weight: 800;
  line-height: 1.18;
  letter-spacing: -0.01em;
  color: var(--c-white);
  max-width: 24ch;
}

.page-about .flow-lead {
  margin: 0 0 34px;
  max-width: 62ch;
  font-size: 1rem;
  line-height: 1.78;
  color: var(--c-mist);
}

/* ---------- 通用卡片 ---------- */
.page-about .about-card {
  position: relative;
  min-width: 0;
  padding: 24px 22px 30px;
  background: var(--c-ash);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - var(--about-cut)), calc(100% - var(--about-cut)) 100%, 0 100%);
  transition: background var(--dur) var(--ease);
}

.page-about .about-card:hover {
  background: var(--c-ash-hi);
}

/* ---------- 01 为什么做 ---------- */
.page-about .why-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 18px;
}

@media (min-width: 720px) {
  .page-about .why-grid {
    grid-template-columns: 1.1fr 1fr 1.05fr;
    align-items: start;
    gap: 20px;
  }

  .page-about .why-card:nth-child(2) {
    margin-top: 30px;
  }
}

.page-about .why-card .why-scene {
  margin: 0 0 6px;
  font-size: 0.78rem;
  letter-spacing: 0.1em;
  color: var(--c-mist);
  opacity: 0.9;
}

.page-about .why-card h3 {
  margin: 0 0 12px;
  font-size: 1.12rem;
  font-weight: 700;
  line-height: 1.35;
}

.page-about .why-card > p:not(.why-scene) {
  margin: 0;
  font-size: 0.94rem;
  line-height: 1.72;
  color: var(--c-mist);
}

.page-about .text-link {
  display: inline-block;
  margin-top: 16px;
  font-size: 0.86rem;
  color: var(--c-gold);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color var(--dur-fast) var(--ease), border-color var(--dur-fast) var(--ease);
}

.page-about .text-link:hover {
  color: var(--c-gold-hi);
  border-bottom-color: var(--c-gold-hi);
}

/* ---------- 02 四道工序 ---------- */
.page-about .process-figure {
  margin: 0 0 28px;
}

.page-about .process-figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 14 / 9;
  object-fit: cover;
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - var(--about-cut)), calc(100% - var(--about-cut)) 100%, 0 100%);
}

.page-about .process-list {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 16px;
  margin: 0;
  padding: 0;
  list-style: none;
}

@media (min-width: 760px) {
  .page-about .process-list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 20px;
  }
}

@media (min-width: 1140px) {
  .page-about .process-list {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

.page-about .process-step {
  min-width: 0;
  padding: 20px 20px 26px;
  background: var(--c-deep);
  border-top: 2px solid var(--c-iron);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 18px), calc(100% - 18px) 100%, 0 100%);
  transition: border-top-color var(--dur) var(--ease), background var(--dur) var(--ease);
}

.page-about .process-step:hover {
  background: var(--c-ash);
  border-top-color: var(--c-gold);
}

.page-about .process-idx {
  display: block;
  font-size: 0.78rem;
  letter-spacing: 0.1em;
  color: var(--c-gold);
}

.page-about .process-name {
  display: block;
  margin: 10px 0 8px;
  font-size: 1.16rem;
  font-weight: 700;
}

.page-about .process-time {
  display: inline-block;
  padding: 3px 9px;
  font-size: 0.78rem;
  color: var(--c-gold-hi);
  border: 1px solid var(--c-iron);
}

.page-about .process-desc {
  margin: 14px 0 0;
  font-size: 0.9rem;
  line-height: 1.72;
  color: var(--c-mist);
}

/* ---------- 03 覆盖范围 ---------- */
.page-about .coverage-figure {
  margin: 0 0 30px;
}

.page-about .coverage-figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 10;
  object-fit: cover;
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - var(--about-cut)), calc(100% - var(--about-cut)) 100%, 0 100%);
}

.page-about .cover-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 16px;
  margin: 0;
  padding: 0;
  list-style: none;
}

@media (min-width: 680px) {
  .page-about .cover-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 1100px) {
  .page-about .cover-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 20px;
  }

  .page-about .cover-card:first-child {
    grid-column: span 2;
  }
}

.page-about .cover-stat {
  display: flex;
  align-items: baseline;
  gap: 6px;
  margin: 0 0 10px;
}

.page-about .cover-count {
  font-size: clamp(2rem, 5vw, 2.8rem);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--c-gold-hi);
}

.page-about .cover-unit {
  font-size: 0.8rem;
  color: var(--c-mist);
}

.page-about .cover-card h3 {
  margin: 0 0 10px;
  font-size: 1.1rem;
  font-weight: 700;
}

.page-about .cover-card p:not(.cover-stat):not(.cover-freq) {
  margin: 0;
  font-size: 0.92rem;
  line-height: 1.72;
  color: var(--c-mist);
}

.page-about .cover-freq {
  margin: 16px 0 0;
  padding-top: 14px;
  font-size: 0.78rem;
  letter-spacing: 0.06em;
  color: var(--c-mist);
  border-top: 1px solid var(--c-iron);
}

/* ---------- 04 团队 ---------- */
.page-about .team-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 18px;
}

@media (min-width: 700px) {
  .page-about .team-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 20px;
  }
}

@media (min-width: 1100px) {
  .page-about .team-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .team-card:nth-child(2),
  .page-about .team-card:nth-child(4) {
    margin-top: 26px;
  }
}

.page-about .team-name {
  margin: 0 0 10px;
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--c-white);
}

.page-about .team-role {
  margin: 0;
  font-size: 0.9rem;
  line-height: 1.7;
  color: var(--c-mist);
}

.page-about .team-toggle {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-top: 16px;
  padding: 6px 11px;
  font-family: var(--font-sans);
  font-size: 0.78rem;
  color: var(--c-gold);
  background: transparent;
  border: 1px solid var(--c-iron);
  cursor: pointer;
  transition: color var(--dur-fast) var(--ease), border-color var(--dur-fast) var(--ease);
}

.page-about .team-toggle:hover {
  color: var(--c-gold-hi);
  border-color: var(--c-gold);
}

.page-about .team-toggle:focus-visible {
  outline: 2px solid var(--c-gold-hi);
  outline-offset: 2px;
}

.page-about .team-toggle .expand-caret {
  display: inline-block;
  width: 6px;
  height: 6px;
  border-right: 1.5px solid currentColor;
  border-bottom: 1.5px solid currentColor;
  transform: rotate(-45deg);
  transition: transform var(--dur-fast) var(--ease);
}

.page-about .team-toggle[aria-expanded="true"] .expand-caret {
  transform: rotate(45deg);
}

.page-about .team-card .expand-panel p {
  margin: 14px 0 0;
  padding-top: 14px;
  font-size: 0.86rem;
  line-height: 1.7;
  color: var(--c-mist);
  border-top: 1px solid var(--c-iron);
}

/* ---------- 05 历程 ---------- */
.page-about .era-list {
  display: flex;
  flex-direction: column;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .era-item {
  display: grid;
  grid-template-columns: 62px minmax(0, 1fr);
  gap: 18px;
  padding: 22px 0;
  border-top: 1px solid var(--c-iron);
}

.page-about .era-item:last-child {
  border-bottom: 1px solid var(--c-iron);
}

@media (min-width: 768px) {
  .page-about .era-item {
    grid-template-columns: 88px minmax(0, 1fr);
    gap: 28px;
    padding: 26px 0;
  }
}

.page-about .era-year {
  padding-top: 2px;
  font-size: 1rem;
  letter-spacing: 0.02em;
  color: var(--c-gold);
}

.page-about .era-body {
  min-width: 0;
}

.page-about .era-body h3 {
  margin: 0 0 8px;
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--c-white);
}

.page-about .era-body p {
  margin: 0;
  max-width: 58ch;
  font-size: 0.94rem;
  line-height: 1.75;
  color: var(--c-mist);
}

.page-about .era-foot {
  margin: 26px 0 0;
  max-width: 60ch;
  padding-left: 18px;
  font-size: 0.95rem;
  line-height: 1.75;
  color: var(--c-mist);
  border-left: 2px solid var(--c-gold);
}

/* ---------- 06 数据 ---------- */
.page-about .data-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
  margin: 0;
}

@media (min-width: 700px) {
  .page-about .data-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 18px;
  }
}

.page-about .data-cell {
  min-width: 0;
  padding: 20px 20px 22px;
  background: var(--c-deep);
  border-left: 2px solid var(--c-ash);
  transition: border-left-color var(--dur) var(--ease);
}

.page-about .data-cell:hover {
  border-left-color: var(--c-gold);
}

.page-about .data-cell dt {
  margin: 0 0 10px;
  font-size: 0.76rem;
  letter-spacing: 0.16em;
  color: var(--c-mist);
}

.page-about .data-cell dd {
  margin: 0;
  font-size: 0.93rem;
  line-height: 1.75;
  color: var(--c-white);
}

.page-about .data-val {
  display: inline-block;
  margin-right: 8px;
  color: var(--c-gold-hi);
  letter-spacing: -0.01em;
}

/* ---------- 行动区 ---------- */
.page-about .about-cta {
  position: relative;
  min-width: 0;
  padding: 36px 24px 42px;
  background: linear-gradient(120deg, #1B1E23 0%, #101216 62%, #17120E 100%);
  border-left: 3px solid var(--c-flame);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 26px), calc(100% - 26px) 100%, 0 100%);
}

@media (min-width: 768px) {
  .page-about .about-cta {
    padding: 44px 40px 50px;
  }
}

.page-about .about-cta h2 {
  font-size: clamp(1.4rem, 3vw, 1.95rem);
  margin-bottom: 14px;
}

.page-about .about-cta p {
  margin: 0;
  max-width: 58ch;
  font-size: 0.96rem;
  line-height: 1.78;
  color: var(--c-mist);
}

.page-about .cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 26px;
}

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

/* ---------- 降低动效 ---------- */
@media (prefers-reduced-motion: reduce) {
  .page-about .about-card,
  .page-about .process-step,
  .page-about .data-cell,
  .page-about .rail-link,
  .page-about .team-toggle .expand-caret {
    transition: none;
  }
}