.page-about {
  display: block;
  background: var(--ink-900);
  color: var(--paper);
  overflow-x: hidden;
}

/* ---------- 面包屑 ---------- */
.page-about .breadcrumb {
  padding-top: calc(var(--header-h) + 20px);
  padding-bottom: 4px;
}

.page-about .crumb-list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  margin: 0;
  padding: 0;
  list-style: none;
  font-size: 13px;
  letter-spacing: 0.08em;
  color: var(--mist);
}

.page-about .crumb-list li {
  display: flex;
  align-items: center;
}

.page-about .crumb-list li + li::before {
  content: "/";
  margin: 0 10px;
  color: var(--line);
}

.page-about .crumb-list a {
  color: var(--mist);
  text-decoration: none;
  transition: color 0.18s var(--ease);
}

.page-about .crumb-list a:hover {
  color: var(--cyan);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding: clamp(34px, 5.5vw, 68px) 0 0;
  overflow: hidden;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0 0 42% 0;
  background:
    radial-gradient(58% 78% at 10% 6%, rgba(79, 209, 224, 0.1), transparent 62%),
    radial-gradient(48% 68% at 90% 0%, rgba(216, 169, 59, 0.13), transparent 60%);
  pointer-events: none;
}

.page-about .about-hero__inner {
  position: relative;
}

.page-about .about-h1 {
  margin: 16px 0 0;
  font-size: clamp(31px, 6.2vw, 74px);
  font-weight: 200;
  line-height: 1.04;
  letter-spacing: -0.025em;
  max-width: 15em;
}

.page-about .about-hero__lede {
  margin: clamp(20px, 3vw, 32px) 0 0;
  max-width: 34em;
  font-size: clamp(15px, 1.3vw, 17px);
  line-height: 1.85;
  color: var(--mist);
}

.page-about .hero-facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: clamp(32px, 5vw, 52px) 0 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--line);
  border-left: 1px solid var(--line);
}

.page-about .hero-facts li {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 18px 16px;
  border-right: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.page-about .hero-facts__num {
  font-size: 26px;
  font-weight: 500;
  line-height: 1;
  color: var(--gold);
}

.page-about .hero-facts__label {
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--mist);
}

.page-about .hero-visual {
  position: relative;
  margin: clamp(34px, 5.5vw, 62px) 0 0;
  height: clamp(140px, 24vw, 280px);
  overflow: hidden;
  border-top: 1px solid var(--line);
}

.page-about .hero-visual::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(
    180deg,
    var(--ink-900) 0%,
    rgba(11, 16, 48, 0.12) 45%,
    var(--ink-900) 100%
  );
  pointer-events: none;
}

.page-about .hero-visual__img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.72;
}

/* ---------- 右侧锚点索引 ---------- */
.page-about .about-rail {
  display: none;
}

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

.page-about .rail-link {
  display: block;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--mist);
  text-decoration: none;
  padding: 4px 0 4px 12px;
  border-left: 1px solid var(--line);
  transition: color 0.18s var(--ease), border-color 0.18s var(--ease);
}

.page-about .rail-link:hover,
.page-about .rail-link:focus-visible {
  color: var(--gold);
  border-left-color: var(--gold);
}

/* ---------- 通用章节 ---------- */
.page-about .section {
  padding: clamp(62px, 9.5vw, 116px) 0;
}

.page-about .about-h2 {
  margin: 0 0 16px;
  font-size: clamp(23px, 3.3vw, 38px);
  font-weight: 600;
  line-height: 1.2;
  letter-spacing: -0.01em;
}

.page-about .about-lede {
  margin: 0;
  max-width: 34em;
  font-size: 15px;
  line-height: 1.85;
  color: var(--mist);
}

/* ---------- 时间轴 ---------- */
.page-about .tl-track {
  position: relative;
  display: flex;
  gap: 26px;
  margin: clamp(34px, 5vw, 56px) 0 0;
  padding: 0 0 20px;
  list-style: none;
  overflow-x: auto;
  scroll-snap-type: x proximity;
  -webkit-overflow-scrolling: touch;
}

.page-about .tl-item {
  position: relative;
  flex: 0 0 min(74vw, 228px);
  padding-top: 40px;
  scroll-snap-align: start;
}

.page-about .tl-item::after {
  content: "";
  position: absolute;
  top: 6px;
  left: 7px;
  right: -26px;
  height: 1px;
  background: var(--line);
}

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

.page-about .tl-dot {
  position: absolute;
  top: 0;
  left: 0;
  z-index: 1;
  width: 13px;
  height: 13px;
  border-radius: 50%;
  background: var(--gold);
  box-shadow: 0 0 0 4px rgba(216, 169, 59, 0.12);
  transition: background 0.18s var(--ease), box-shadow 0.18s var(--ease);
}

.page-about .tl-year {
  display: block;
  margin-bottom: 10px;
  font-family: var(--font-mono);
  font-size: 15px;
  letter-spacing: 0.08em;
  color: var(--gold);
}

.page-about .tl-desc {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--mist);
  transition: color 0.2s var(--ease);
}

.page-about .tl-item:hover .tl-desc,
.page-about .tl-item:focus-visible .tl-desc {
  color: var(--paper);
}

.page-about .tl-item:hover .tl-dot,
.page-about .tl-item:focus-visible .tl-dot {
  background: var(--amber);
  box-shadow: 0 0 0 6px rgba(240, 138, 60, 0.16);
}

.page-about .tl-item:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 6px;
}

/* ---------- 团队 ---------- */
.page-about .team-grid {
  display: grid;
  gap: clamp(30px, 4.5vw, 56px);
}

.page-about .team-list {
  margin: clamp(28px, 4vw, 44px) 0 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--line);
}

.page-about .team-row {
  padding: 22px 0;
  border-bottom: 1px solid var(--line);
}

.page-about .team-row__head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 16px;
}

.page-about .team-row__name {
  font-size: 17px;
  font-weight: 600;
  letter-spacing: 0.02em;
}

.page-about .team-row__num {
  font-size: 14px;
  letter-spacing: 0.08em;
  color: var(--gold);
}

.page-about .team-row__text {
  margin: 10px 0 14px;
  font-size: 14px;
  line-height: 1.8;
  color: var(--mist);
}

.page-about .team-bar {
  height: 3px;
  overflow: hidden;
  background: rgba(168, 178, 204, 0.16);
}

.page-about .team-bar__fill {
  display: block;
  height: 100%;
  width: var(--bar-w, 0%);
  background: linear-gradient(90deg, var(--cyan), var(--gold));
}

.page-about .team-row:nth-child(1) {
  --bar-w: 37.5%;
}

.page-about .team-row:nth-child(2) {
  --bar-w: 25%;
}

.page-about .team-row:nth-child(3) {
  --bar-w: 37.5%;
}

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

.page-about .team-figure img {
  display: block;
  width: 100%;
  max-width: 400px;
  height: auto;
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.page-about .team-figure__cap {
  margin: 14px 0 0;
  max-width: 30em;
  font-size: 12.5px;
  line-height: 1.7;
  letter-spacing: 0.02em;
  color: var(--mist);
}

/* ---------- 内容流程 ---------- */
.page-about .flow {
  display: grid;
  gap: 1px;
  margin: clamp(30px, 4.5vw, 48px) 0 0;
  padding: 0;
  list-style: none;
  background: rgba(238, 241, 248, 0.12);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}

.page-about .flow-step {
  position: relative;
  padding: 28px 22px 32px;
  background: var(--teal-900);
}

.page-about .flow-step::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 3px;
}

.page-about .flow-step:nth-child(1)::before {
  background: var(--cyan);
}

.page-about .flow-step:nth-child(2)::before {
  background: var(--gold);
}

.page-about .flow-step:nth-child(3)::before {
  background: var(--amber);
}

.page-about .flow-step:nth-child(4)::before {
  background: var(--coral);
}

.page-about .flow-idx {
  display: block;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.16em;
  color: var(--mist);
}

.page-about .flow-title {
  margin: 12px 0 10px;
  font-size: 19px;
  font-weight: 600;
  letter-spacing: 0.02em;
}

.page-about .flow-text {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--mist);
}

.page-about .flow-figure {
  margin: clamp(28px, 4vw, 46px) 0 0;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}

.page-about .flow-figure img {
  display: block;
  width: 100%;
  height: auto;
}

/* ---------- 内容来源 ---------- */
.page-about .source-grid {
  display: grid;
  gap: clamp(28px, 4vw, 48px);
}

.page-about .source-note {
  margin: 18px 0 0;
  max-width: 34em;
  font-size: 14px;
  line-height: 1.85;
  color: var(--mist);
}

.page-about .source-note a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(79, 209, 224, 0.35);
  transition: border-color 0.18s var(--ease), color 0.18s var(--ease);
}

.page-about .source-note a:hover {
  color: var(--gold);
  border-bottom-color: var(--gold);
}

.page-about .source-figure {
  padding: 28px 24px 30px;
  border: 1px solid rgba(216, 169, 59, 0.32);
  border-radius: var(--radius);
  background: linear-gradient(160deg, rgba(216, 169, 59, 0.09), rgba(62, 16, 36, 0.2));
}

.page-about .source-figure__num {
  display: block;
  font-size: clamp(40px, 6vw, 62px);
  font-weight: 500;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--gold);
}

.page-about .source-figure__label {
  display: block;
  margin-top: 12px;
  font-size: 12px;
  letter-spacing: 0.18em;
  color: var(--mist);
}

.page-about .source-figure__text {
  margin: 20px 0 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--mist);
}

/* ---------- 使用场景 ---------- */
.page-about .audience-head {
  display: grid;
  gap: clamp(20px, 3vw, 36px);
}

.page-about .audience-stat {
  margin: 0;
  padding-left: 16px;
  border-left: 2px solid var(--gold);
  font-size: 14px;
  line-height: 1.85;
  color: var(--mist);
}

.page-about .audience-stat__num {
  display: block;
  margin-bottom: 8px;
  font-size: 30px;
  font-weight: 500;
  line-height: 1;
  color: var(--gold);
}

.page-about .scene-list {
  display: grid;
  gap: clamp(16px, 2.4vw, 24px);
  margin: clamp(30px, 4.5vw, 48px) 0 0;
  padding: 0;
  list-style: none;
}

.page-about .scene-card {
  padding: 24px 20px 28px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(21, 27, 68, 0.55);
  transition: border-color 0.22s var(--ease), box-shadow 0.22s var(--ease), transform 0.22s var(--ease);
}

.page-about .scene-card:hover {
  border-color: rgba(216, 169, 59, 0.5);
  box-shadow: var(--shadow-card);
  transform: translateY(-3px);
}

.page-about .scene-card p {
  margin: 16px 0 0;
  font-size: 14px;
  line-height: 1.85;
  color: var(--mist);
}

.page-about .scene-card a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(79, 209, 224, 0.35);
  transition: color 0.18s var(--ease), border-color 0.18s var(--ease);
}

.page-about .scene-card a:hover {
  color: var(--gold);
  border-bottom-color: var(--gold);
}

/* ---------- 长期维护 ---------- */
.page-about .metric-list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: clamp(28px, 4vw, 46px) 0 0;
  padding: 0;
  list-style: none;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .metric-list li {
  padding: 22px 18px 24px;
  background: var(--ink-800);
}

.page-about .metric-list .mono {
  display: block;
  margin-bottom: 10px;
  font-size: 24px;
  font-weight: 500;
  line-height: 1;
  color: var(--paper);
}

.page-about .metric-label {
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--mist);
}

.page-about .upkeep-note {
  margin-top: clamp(26px, 3.5vw, 40px);
}

/* ---------- 收束 ---------- */
.page-about .about-outro {
  position: relative;
  padding: clamp(70px, 11vw, 148px) 0 clamp(78px, 12vw, 164px);
}

.page-about .about-outro::before {
  content: "";
  position: absolute;
  top: 0;
  left: var(--gutter);
  right: var(--gutter);
  height: 1px;
  background: linear-gradient(90deg, var(--gold), rgba(216, 169, 59, 0.12) 45%, transparent);
}

.page-about .outro-line {
  margin: 0;
  font-size: clamp(23px, 3.9vw, 42px);
  font-weight: 200;
  line-height: 1.32;
  letter-spacing: -0.02em;
  color: var(--paper);
}

.page-about .outro-line--dim {
  margin-top: 16px;
  font-size: clamp(17px, 2.5vw, 27px);
  color: var(--mist);
}

/* ---------- 响应式 ---------- */
@media (min-width: 720px) {
  .page-about .hero-facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

@media (min-width: 860px) {
  .page-about .flow {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (min-width: 900px) {
  .page-about .tl-track {
    overflow-x: visible;
  }

  .page-about .tl-item {
    flex: 1 1 0;
    min-width: 0;
  }

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

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

@media (min-width: 940px) {
  .page-about .team-grid {
    grid-template-columns: minmax(0, 8fr) minmax(0, 4fr);
    align-items: start;
  }
}

@media (min-width: 800px) {
  .page-about .metric-list {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (min-width: 1560px) {
  .page-about .about-rail {
    display: block;
    position: fixed;
    top: 50%;
    right: 30px;
    z-index: 20;
    transform: translateY(-50%);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about * {
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
  }

  .page-about .scene-card:hover {
    transform: none;
  }
}