.page-about {
  --about-line: rgba(16, 42, 67, 0.1);
  --about-cyan-ghost: rgba(22, 217, 227, 0.35);
  color: var(--graphite);
  padding-bottom: clamp(48px, 7vw, 96px);
  overflow-x: clip;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding-top: clamp(12px, 2.4vw, 26px);
  padding-bottom: clamp(28px, 4vw, 46px);
}

.page-about .about-hero__grid {
  display: grid;
  gap: clamp(24px, 4vw, 44px);
}

.page-about .about-hero__lead {
  min-width: 0;
}

.page-about .about-kicker {
  margin: 18px 0 0;
  font-size: 12px;
  letter-spacing: 0.18em;
  color: var(--slate);
}

.page-about .about-hero__title {
  margin: 12px 0 20px;
  font-family: var(--sans);
  font-weight: 900;
  font-size: clamp(34px, 8.4vw, 72px);
  line-height: 0.98;
  letter-spacing: -0.04em;
  color: var(--ink);
}

.page-about .about-hero__quote {
  margin: 0 0 20px;
  padding-left: 16px;
  border-left: 3px solid var(--amber);
  font-family: var(--serif);
  font-size: clamp(17px, 2.2vw, 22px);
  line-height: 1.6;
  color: var(--ink);
}

.page-about .about-hero__text {
  max-width: 62ch;
  font-size: clamp(15px, 1.6vw, 17px);
  line-height: 1.85;
  color: var(--graphite);
}

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

.page-about .about-hero__figure {
  margin: 0;
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: var(--ink);
  border: 1px solid var(--about-line);
}

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

/* ---------- 数据条 ---------- */
.page-about .about-stats {
  padding: clamp(18px, 3vw, 28px) 0;
  background:
    linear-gradient(180deg, rgba(22, 217, 227, 0.14), rgba(22, 217, 227, 0) 70%),
    var(--ink);
  border-top: 1px solid var(--line-dark);
  border-bottom: 1px solid var(--line-dark);
}

.page-about .about-stats__grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px 12px;
}

.page-about .about-stat {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding-left: 14px;
  border-left: 2px solid var(--amber);
}

.page-about .about-stat__num {
  font-family: var(--mono);
  font-weight: 500;
  font-size: clamp(26px, 4.6vw, 40px);
  line-height: 1;
  color: var(--cyan);
  letter-spacing: -0.02em;
}

.page-about .about-stat__plus {
  color: var(--amber);
}

.page-about .about-stat__label {
  font-size: 13px;
  line-height: 1.5;
  color: rgba(247, 241, 227, 0.72);
}

/* ---------- 章节骨架 ---------- */
.page-about .about-chapters {
  padding-top: clamp(32px, 5vw, 56px);
}

.page-about .about-chapters__grid {
  display: grid;
  gap: 24px;
}

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

.page-about .about-rail__title {
  margin: 0 0 10px;
  font-size: 11px;
  letter-spacing: 0.2em;
  color: var(--slate);
}

.page-about .about-rail__list {
  display: flex;
  gap: 8px;
  margin: 0;
  padding: 0 0 6px;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: thin;
}

.page-about .about-rail__list li {
  flex: 0 0 auto;
}

.page-about .about-rail__link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 14px;
  border-radius: var(--radius-pill);
  border: 1px solid var(--about-line);
  background: var(--paper);
  color: var(--ink);
  font-size: 13px;
  text-decoration: none;
  white-space: nowrap;
  transition: border-color 0.2s var(--ease), background 0.2s var(--ease);
}

.page-about .about-rail__link:hover,
.page-about .about-rail__link:focus-visible {
  border-color: var(--cyan);
  background: var(--cream);
}

.page-about .about-rail__idx {
  font-family: var(--mono);
  font-size: 11px;
  color: var(--vermilion);
}

/* ---------- 画板 ---------- */
.page-about .about-flow {
  min-width: 0;
}

.page-about .about-board {
  position: relative;
  margin-bottom: clamp(18px, 3vw, 28px);
  padding: clamp(22px, 4vw, 44px);
  border-radius: var(--radius-lg);
  background: var(--paper);
  border: 1px solid var(--about-line);
  box-shadow: var(--shadow-card);
}

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

.page-about .about-board--dark {
  background:
    radial-gradient(120% 90% at 100% 0%, rgba(22, 217, 227, 0.16), transparent 60%),
    var(--ink);
  border-color: transparent;
  color: var(--cream);
}

.page-about .about-board__head {
  display: flex;
  align-items: flex-start;
  gap: 14px;
  margin-bottom: 16px;
}

.page-about .about-num {
  font-family: var(--mono);
  font-weight: 500;
  font-size: clamp(34px, 5.6vw, 56px);
  line-height: 0.85;
  color: var(--cyan);
  opacity: 0.55;
  flex: 0 0 auto;
}

.page-about .about-board--dark .about-num {
  opacity: 0.85;
}

.page-about .about-board__title {
  margin: 0;
  font-family: var(--sans);
  font-weight: 900;
  font-size: clamp(21px, 3.4vw, 32px);
  line-height: 1.2;
  letter-spacing: -0.02em;
  color: var(--ink);
}

.page-about .about-board--dark .about-board__title {
  color: var(--paper);
}

.page-about .about-board__lead {
  margin: 0 0 24px;
  font-size: clamp(14px, 1.6vw, 16px);
  line-height: 1.85;
  color: var(--slate);
}

.page-about .about-board--dark .about-board__lead {
  color: rgba(247, 241, 227, 0.76);
}

.page-about .about-flow .prose {
  max-width: 720px;
}

/* ---------- 产品矩阵 ---------- */
.page-about .about-products {
  display: grid;
  gap: 12px;
  margin-bottom: 26px;
}

.page-about .about-product {
  border-radius: var(--radius-md);
  background: var(--cream);
  border-left: 3px solid var(--cyan);
  padding: 4px 18px;
  transition: transform 0.22s var(--ease), border-color 0.22s var(--ease);
}

.page-about .about-product:hover {
  transform: translateY(-2px);
}

.page-about .about-product[open] {
  border-left-color: var(--amber);
}

.page-about .about-product summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 14px 0;
  cursor: pointer;
  font-family: var(--sans);
  font-weight: 700;
  font-size: 16px;
  color: var(--ink);
  list-style: none;
}

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

.page-about .about-product summary::after {
  content: "+";
  font-family: var(--mono);
  font-size: 18px;
  line-height: 1;
  color: var(--slate);
}

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

.page-about .about-product__tag {
  margin-left: auto;
  padding: 3px 9px;
  border-radius: var(--radius-pill);
  background: rgba(11, 27, 43, 0.08);
  font-size: 11px;
  color: var(--panel);
  white-space: nowrap;
}

.page-about .about-product p {
  margin: 0 0 16px;
  font-size: 14px;
  line-height: 1.8;
  color: var(--graphite);
}

.page-about .about-map__figure {
  margin: 0;
  border-radius: var(--radius-md);
  overflow: hidden;
  background: var(--panel);
}

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

/* ---------- 时间线 ---------- */
.page-about .about-timeline {
  display: flex;
  gap: 14px;
  padding-bottom: 14px;
  overflow-x: auto;
  scroll-snap-type: x mandatory;
  scrollbar-width: thin;
  scrollbar-color: var(--cyan) transparent;
}

.page-about .about-timeline:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 6px;
  border-radius: var(--radius-md);
}

.page-about .about-stage {
  flex: 0 0 min(278px, 76vw);
  scroll-snap-align: start;
  padding: 20px;
  border-radius: var(--radius-md);
  background: var(--panel);
  border: 1px solid var(--line-dark);
}

.page-about .about-stage__dot {
  display: block;
  width: 10px;
  height: 10px;
  margin-bottom: 14px;
  border-radius: 50%;
  background: var(--amber);
  box-shadow: 0 0 0 5px rgba(245, 166, 35, 0.16);
}

.page-about .about-stage__phase {
  margin: 0 0 6px;
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--cyan);
}

.page-about .about-stage__title {
  margin: 0 0 8px;
  font-family: var(--sans);
  font-weight: 700;
  font-size: 18px;
  color: var(--paper);
}

.page-about .about-stage p {
  margin: 0;
  font-size: 13.5px;
  line-height: 1.8;
  color: rgba(247, 241, 227, 0.74);
}

.page-about .about-history__figure {
  margin: 22px 0 0;
  border-radius: var(--radius-md);
  overflow: hidden;
  background: var(--panel-deep);
}

/* ---------- 同步机制 ---------- */
.page-about .about-sync {
  display: grid;
  gap: 24px;
}

.page-about .about-sync__text p {
  margin: 0 0 14px;
  font-size: 15px;
  line-height: 1.9;
  color: var(--graphite);
}

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

.page-about .about-checks {
  display: grid;
  gap: 10px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-check {
  display: flex;
  gap: 14px;
  padding: 16px;
  border-radius: var(--radius-md);
  background: var(--cream);
  border: 1px solid var(--about-line);
}

.page-about .about-check__idx {
  flex: 0 0 auto;
  width: 28px;
  height: 28px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  background: var(--ink);
  color: var(--cyan);
  font-size: 12px;
}

.page-about .about-check h3 {
  margin: 0 0 4px;
  font-family: var(--sans);
  font-weight: 700;
  font-size: 15px;
  color: var(--ink);
}

.page-about .about-check p {
  margin: 0;
  font-size: 13.5px;
  line-height: 1.75;
  color: var(--slate);
}

/* ---------- 规模数据 ---------- */
.page-about .about-metrics {
  display: grid;
  gap: 14px;
  margin-bottom: 28px;
}

.page-about .about-metric {
  display: grid;
  grid-template-columns: 6px auto 1fr;
  align-items: center;
  gap: 12px;
  padding: 12px 14px;
  border-radius: var(--radius-sm);
  background: rgba(255, 253, 247, 0.05);
  border: 1px solid var(--line-dark);
}

.page-about .about-metric__bar {
  display: block;
  width: 6px;
  height: 30px;
  border-radius: var(--radius-pill);
  background: linear-gradient(180deg, var(--amber), var(--vermilion));
}

.page-about .about-metric__num {
  font-family: var(--mono);
  font-weight: 500;
  font-size: clamp(20px, 3vw, 26px);
  color: var(--paper);
  white-space: nowrap;
}

.page-about .about-metric__label {
  font-size: 13px;
  line-height: 1.6;
  color: rgba(247, 241, 227, 0.72);
}

.page-about .about-assure {
  display: grid;
  gap: 12px;
}

.page-about .about-assure__item {
  padding: 16px 18px;
  border-radius: var(--radius-md);
  background: rgba(22, 217, 227, 0.06);
  border: 1px solid var(--line-dark);
}

.page-about .about-assure__item p {
  margin: 10px 0 0;
  font-size: 13.5px;
  line-height: 1.8;
  color: rgba(247, 241, 227, 0.8);
}

/* ---------- 团队角色 ---------- */
.page-about .about-roles {
  display: grid;
  gap: 12px;
}

.page-about .about-role {
  padding: 18px 18px 20px;
  border-radius: var(--radius-md);
  background: var(--cream);
  border-top: 3px solid var(--cyan);
}

.page-about .about-role:nth-child(even) {
  border-top-color: var(--amber);
}

.page-about .about-role__idx {
  display: block;
  margin-bottom: 10px;
  font-size: 12px;
  color: var(--vermilion);
}

.page-about .about-role h3 {
  margin: 0 0 8px;
  font-family: var(--sans);
  font-weight: 700;
  font-size: 17px;
  color: var(--ink);
}

.page-about .about-role p {
  margin: 0;
  font-size: 13.5px;
  line-height: 1.8;
  color: var(--graphite);
}

/* ---------- 合作 CTA ---------- */
.page-about .about-cta .about-board__title {
  max-width: 26ch;
}

.page-about .about-cta__grid {
  display: grid;
  gap: 12px;
  margin: 8px 0 26px;
}

.page-about .about-cta__col {
  padding: 18px;
  border-radius: var(--radius-md);
  background: rgba(255, 253, 247, 0.05);
  border-left: 2px solid var(--cyan);
}

.page-about .about-cta__col h3 {
  margin: 0 0 8px;
  font-family: var(--sans);
  font-weight: 700;
  font-size: 16px;
  color: var(--cyan-soft);
}

.page-about .about-cta__col p {
  margin: 0;
  font-size: 13.5px;
  line-height: 1.8;
  color: rgba(247, 241, 227, 0.78);
}

.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

/* ---------- 显现动效 ---------- */
.page-about [data-reveal] {
  opacity: 1;
}

.page-about .js [data-reveal] {
  opacity: 0;
  transform: translateY(12px);
  transition: opacity 0.32s var(--ease), transform 0.32s var(--ease);
}

.page-about .js [data-reveal].is-visible {
  opacity: 1;
  transform: translateY(0);
}

/* ---------- 断点 ---------- */
@media (min-width: 640px) {
  .page-about .about-products {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-about .about-stats__grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

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

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

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.12fr) minmax(0, 0.88fr);
    align-items: center;
  }

  .page-about .about-sync {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    align-items: start;
    gap: 32px;
  }

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

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

@media (min-width: 1000px) {
  .page-about .about-chapters__grid {
    grid-template-columns: 196px minmax(0, 1fr);
    gap: clamp(28px, 3.4vw, 48px);
    align-items: start;
  }

  .page-about .about-rail {
    position: sticky;
    top: 104px;
  }

  .page-about .about-rail__list {
    flex-direction: column;
    overflow: visible;
    padding-bottom: 0;
    gap: 6px;
  }

  .page-about .about-rail__link {
    width: 100%;
    border-radius: var(--radius-sm);
    background: transparent;
    border-color: transparent;
  }

  .page-about .about-rail__link:hover,
  .page-about .about-rail__link:focus-visible {
    background: var(--paper);
    border-color: var(--cyan);
  }

  .page-about .about-board {
    padding: clamp(32px, 3.6vw, 52px);
  }

  .page-about .about-products {
    gap: 14px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .js [data-reveal] {
    opacity: 1;
    transform: none;
    transition: none;
  }

  .page-about .about-product:hover {
    transform: none;
  }
}