.page-about {
  --about-rail: 92px;
  background: var(--paper);
  color: var(--text);
}

.page-about a {
  color: inherit;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding: clamp(28px, 4vw, 52px) 0 clamp(56px, 8vw, 108px);
  color: var(--paper);
  border-bottom: 1px solid var(--line);
}

.page-about .about-hero .breadcrumb ol {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin: 0 0 clamp(28px, 4vw, 48px);
  padding: 0;
  list-style: none;
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--slate);
}

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

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

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

.page-about .about-hero__grid {
  display: grid;
  gap: clamp(32px, 5vw, 56px);
}

.page-about .about-hero h1 {
  margin: 14px 0 24px;
  font-family: var(--font-serif);
  font-weight: 900;
  font-size: clamp(2rem, 5.4vw, 3.5rem);
  line-height: 1.16;
  letter-spacing: -0.02em;
  color: var(--champagne);
}

.page-about .about-hero__intro {
  max-width: 48ch;
  margin: 0 0 18px;
  font-size: 16px;
  line-height: 1.85;
  color: rgba(247, 243, 234, 0.84);
}

.page-about .about-hero__intro--minor {
  font-size: 14px;
  line-height: 1.8;
  color: var(--slate);
  padding-left: 16px;
  border-left: 1px solid var(--brass);
}

.page-about .about-hero__stats {
  align-self: start;
  border: 1px solid var(--line);
  background: rgba(18, 51, 44, 0.72);
}

.page-about .stat {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 20px 22px;
}

.page-about .stat + .stat {
  border-top: 1px solid var(--line-soft);
}

.page-about .stat__num {
  font-family: var(--font-num);
  font-size: 2.4rem;
  line-height: 1;
  color: var(--amber);
  font-variant-numeric: tabular-nums;
}

.page-about .stat__label {
  font-size: 13px;
  line-height: 1.65;
  color: rgba(240, 221, 184, 0.78);
}

/* ---------- 通用小节标题 ---------- */
.page-about .about-head {
  max-width: 46rem;
  margin: 0 0 clamp(32px, 4vw, 52px);
}

.page-about .about-head--compact {
  margin-bottom: clamp(24px, 3vw, 36px);
}

.page-about .about-head h2 {
  margin: 12px 0 16px;
  font-family: var(--font-serif);
  font-weight: 800;
  font-size: clamp(1.55rem, 3.4vw, 2.35rem);
  line-height: 1.28;
  letter-spacing: -0.02em;
  color: var(--ink);
}

.page-about .about-head p {
  margin: 0;
  font-size: 15px;
  line-height: 1.9;
  color: rgba(27, 43, 51, 0.74);
}

.page-about .about-head--inverse h2 {
  color: var(--champagne);
}

.page-about .about-head--inverse p {
  color: rgba(247, 243, 234, 0.76);
}

/* ---------- 沿革 ---------- */
.page-about .about-history {
  padding: clamp(48px, 7vw, 100px) 0 clamp(56px, 8vw, 108px);
  background: var(--paper);
}

.page-about .about-history__banner {
  margin: 0 0 clamp(32px, 5vw, 64px);
  overflow: hidden;
  border: 1px solid var(--line-soft);
}

.page-about .about-history__banner img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 1400 / 620;
  object-fit: cover;
}

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

.page-about .timeline__rail ol {
  display: flex;
  gap: 10px;
  margin: 0;
  padding: 0 0 8px;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: thin;
}

.page-about .rail-node {
  display: flex;
  align-items: baseline;
  gap: 8px;
  padding: 8px 14px;
  border: 1px solid var(--line-soft);
  text-decoration: none;
  white-space: nowrap;
  transition: border-color var(--dur) var(--ease), background var(--dur) var(--ease);
}

.page-about .rail-node:hover,
.page-about .rail-node:focus-visible {
  border-color: var(--amber);
  background: rgba(231, 181, 99, 0.1);
}

.page-about .rail-node__year {
  font-family: var(--font-num);
  font-size: 1.15rem;
  line-height: 1;
  color: var(--brass);
  font-variant-numeric: tabular-nums;
}

.page-about .rail-node__label {
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--slate);
}

.page-about .rail-node[data-active] {
  border-color: var(--amber);
  background: rgba(231, 181, 99, 0.12);
}

.page-about .rail-node[data-active] .rail-node__year,
.page-about .rail-node[data-active] .rail-node__label {
  color: var(--amber);
}

.page-about .timeline__stages {
  display: grid;
  gap: 18px;
}

.page-about .stage {
  padding: 26px 24px;
  background: rgba(255, 255, 255, 0.68);
  border: 1px solid var(--line-soft);
  border-left: 2px solid var(--brass);
  transition: transform var(--dur) var(--ease), border-color var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
}

.page-about .stage:hover {
  transform: translateY(-2px);
  border-left-color: var(--amber);
  box-shadow: 0 18px 40px -28px rgba(12, 38, 33, 0.55);
}

.page-about .stage__year {
  display: block;
  font-family: var(--font-num);
  font-size: 1.7rem;
  line-height: 1;
  color: var(--brass);
  font-variant-numeric: tabular-nums;
}

.page-about .stage h3 {
  margin: 12px 0 10px;
  font-family: var(--font-serif);
  font-size: 1.2rem;
  font-weight: 700;
  line-height: 1.4;
  color: var(--ink);
}

.page-about .stage p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.9;
  color: rgba(27, 43, 51, 0.76);
}

/* ---------- 校对流程 ---------- */
.page-about .about-process {
  padding: clamp(52px, 8vw, 112px) 0;
  background: var(--ink);
  color: var(--paper);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.page-about .process-grid {
  display: grid;
  gap: clamp(32px, 5vw, 56px);
}

.page-about .flow {
  margin: 0;
  padding: 0;
  list-style: none;
  border: 1px solid var(--line-soft);
}

.page-about .flow__item {
  padding: 24px 22px;
  background: var(--ink);
  transition: background var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.page-about .flow__item + .flow__item {
  border-top: 1px solid var(--line-soft);
}

.page-about .flow__item:hover {
  background: var(--ink-panel);
}

.page-about .flow__num {
  display: block;
  font-family: var(--font-num);
  font-size: 1.8rem;
  line-height: 1;
  color: var(--brass);
  font-variant-numeric: tabular-nums;
  transition: color var(--dur) var(--ease);
}

.page-about .flow__item:hover .flow__num {
  color: var(--amber);
}

.page-about .flow h3 {
  margin: 12px 0 10px;
  font-family: var(--font-serif);
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--champagne);
}

.page-about .flow p {
  margin: 0;
  font-size: 14px;
  line-height: 1.85;
  color: rgba(247, 243, 234, 0.74);
}

.page-about .flow-note {
  margin: 24px 0 0;
  padding-top: 20px;
  border-top: 1px solid var(--line-soft);
  font-size: 14px;
  line-height: 1.85;
  color: rgba(247, 243, 234, 0.7);
}

.page-about .flow-note a {
  color: var(--amber);
  text-decoration: none;
  border-bottom: 1px solid rgba(231, 181, 99, 0.5);
}

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

.page-about .process-media {
  margin: 0;
  align-self: start;
}

.page-about .process-media img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 1100 / 800;
  object-fit: cover;
  border: 1px solid var(--line);
}

.page-about .process-media .media-frame__caption {
  margin-top: 12px;
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--slate);
}

/* ---------- 文档与团队规模 ---------- */
.page-about .about-scale {
  padding: clamp(52px, 8vw, 108px) 0;
  background: var(--paper);
}

.page-about .scale-grid {
  display: grid;
  gap: clamp(32px, 5vw, 56px);
}

.page-about .doc-list {
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .doc-item {
  display: grid;
  grid-template-columns: 40px minmax(0, 1fr);
  gap: 14px;
  padding: 20px 0;
  border-top: 1px solid var(--line-soft);
}

.page-about .doc-item:last-child {
  border-bottom: 1px solid var(--line-soft);
}

.page-about .doc-item__num {
  font-family: var(--font-num);
  font-size: 1.15rem;
  line-height: 1.5;
  color: var(--brass);
  font-variant-numeric: tabular-nums;
}

.page-about .doc-item h3 {
  margin: 0 0 6px;
  font-family: var(--font-serif);
  font-size: 1.02rem;
  font-weight: 700;
  color: var(--ink);
}

.page-about .doc-item p {
  margin: 0;
  font-size: 14px;
  line-height: 1.85;
  color: rgba(27, 43, 51, 0.74);
}

.page-about .scale-side {
  display: grid;
  gap: 1px;
  align-self: start;
  background: var(--line-soft);
  border: 1px solid var(--line-soft);
}

.page-about .fact {
  padding: 22px;
  background: var(--paper);
}

.page-about .fact__num {
  display: block;
  font-family: var(--font-num);
  font-size: 2.1rem;
  line-height: 1;
  color: var(--ink);
  font-variant-numeric: tabular-nums;
}

.page-about .fact__label {
  margin: 10px 0 0;
  font-size: 13px;
  line-height: 1.7;
  color: rgba(27, 43, 51, 0.7);
}

.page-about .team-block {
  padding: 22px;
  background: var(--ink-panel);
}

.page-about .team-block h3 {
  margin: 0 0 16px;
  font-family: var(--font-serif);
  font-size: 1.02rem;
  font-weight: 700;
  color: var(--champagne);
}

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

.page-about .team-list > div {
  padding: 12px 0;
  border-top: 1px solid var(--line-soft);
}

.page-about .team-list dt {
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--amber);
}

.page-about .team-list dd {
  margin: 6px 0 0;
  font-size: 13px;
  line-height: 1.75;
  color: rgba(247, 243, 234, 0.72);
}

/* ---------- 备案与服务信息 ---------- */
.page-about .about-legal {
  padding: clamp(48px, 7vw, 88px) 0;
  background: var(--paper);
  border-top: 1px solid var(--line-soft);
}

.page-about .legal-grid {
  display: grid;
  gap: 1px;
  margin: 0;
  background: var(--line-soft);
  border: 1px solid var(--line-soft);
}

.page-about .legal-cell {
  padding: 18px 20px;
  background: var(--paper);
}

.page-about .legal-cell dt {
  margin-bottom: 8px;
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--slate);
}

.page-about .legal-cell dd {
  margin: 0;
  font-family: ui-monospace, "SFMono-Regular", Menlo, Consolas, monospace;
  font-size: 13px;
  line-height: 1.7;
  color: var(--ink);
  word-break: break-word;
}

.page-about .legal-note {
  max-width: 52rem;
  margin: 24px 0 0;
  font-size: 13px;
  line-height: 1.9;
  color: rgba(27, 43, 51, 0.68);
}

.page-about .legal-note a {
  color: var(--alert);
  text-decoration: none;
  border-bottom: 1px solid rgba(196, 113, 63, 0.45);
}

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

/* ---------- 收尾 ---------- */
.page-about .about-close {
  padding: clamp(52px, 8vw, 104px) 0 clamp(56px, 8vw, 112px);
  background: var(--ink-deep);
  color: var(--paper);
}

.page-about .close-grid {
  display: grid;
  gap: clamp(32px, 5vw, 56px);
}

.page-about .close-copy h2 {
  margin: 0 0 18px;
  font-family: var(--font-serif);
  font-weight: 800;
  font-size: clamp(1.5rem, 3.2vw, 2.15rem);
  line-height: 1.3;
  letter-spacing: -0.02em;
  color: var(--champagne);
}

.page-about .close-copy > p {
  max-width: 46ch;
  margin: 0 0 26px;
  font-size: 15px;
  line-height: 1.9;
  color: rgba(247, 243, 234, 0.78);
}

.page-about .close-links {
  margin: 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--line-soft);
}

.page-about .close-links li {
  border-bottom: 1px solid var(--line-soft);
}

.page-about .close-links a {
  display: block;
  padding: 14px 4px 14px 18px;
  position: relative;
  font-size: 14px;
  line-height: 1.6;
  color: var(--champagne);
  text-decoration: none;
  transition: color var(--dur) var(--ease), padding-left var(--dur) var(--ease);
}

.page-about .close-links a::before {
  content: "";
  position: absolute;
  left: 0;
  top: 50%;
  width: 6px;
  height: 1px;
  background: var(--brass);
  transform: translateY(-50%);
  transition: width var(--dur) var(--ease), background var(--dur) var(--ease);
}

.page-about .close-links a:hover,
.page-about .close-links a:focus-visible {
  color: var(--amber);
  padding-left: 24px;
}

.page-about .close-links a:hover::before,
.page-about .close-links a:focus-visible::before {
  width: 14px;
  background: var(--amber);
}

.page-about .close-media {
  margin: 0;
  align-self: start;
}

.page-about .close-media img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 1200 / 800;
  object-fit: cover;
  border: 1px solid var(--line);
}

/* ---------- 焦点可见性 ---------- */
.page-about a:focus-visible,
.page-about .stage:focus-within {
  outline: 2px solid var(--amber);
  outline-offset: 2px;
}

/* ---------- 响应式 ---------- */
@media (min-width: 720px) {
  .page-about .stat {
    flex-direction: row;
    align-items: baseline;
    gap: 16px;
  }

  .page-about .stat__num {
    flex: 0 0 auto;
    min-width: 3ch;
    font-size: 2.2rem;
  }

  .page-about .flow {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 1px;
    background: var(--line-soft);
  }

  .page-about .flow__item {
    background: var(--ink);
  }

  .page-about .flow__item + .flow__item {
    border-top: 0;
  }

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

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
    align-items: start;
    gap: clamp(40px, 6vw, 88px);
  }

  .page-about .process-grid {
    grid-template-columns: minmax(0, 1.4fr) minmax(0, 0.85fr);
    align-items: start;
  }

  .page-about .scale-grid {
    grid-template-columns: minmax(0, 1.45fr) minmax(0, 0.8fr);
    align-items: start;
  }

  .page-about .close-grid {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.05fr);
    align-items: center;
  }

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

@media (min-width: 880px) {
  .page-about .timeline {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    gap: 0 clamp(28px, 4vw, 56px);
    align-items: start;
  }

  .page-about .timeline__rail {
    position: sticky;
    top: 96px;
    align-self: start;
  }

  .page-about .timeline__rail ol {
    flex-direction: column;
    gap: 0;
    overflow: visible;
    padding: 4px 0 4px 22px;
    border-left: 1px solid var(--line-soft);
  }

  .page-about .rail-node {
    position: relative;
    display: block;
    padding: 14px 0;
    border: 0;
    white-space: normal;
  }

  .page-about .rail-node::before {
    content: "";
    position: absolute;
    left: -26px;
    top: 22px;
    width: 7px;
    height: 7px;
    background: var(--paper);
    border: 1px solid var(--brass);
    transition: background var(--dur) var(--ease), border-color var(--dur) var(--ease);
  }

  .page-about .rail-node:hover,
  .page-about .rail-node:focus-visible {
    background: transparent;
  }

  .page-about .rail-node:hover::before,
  .page-about .rail-node:focus-visible::before,
  .page-about .rail-node[data-active]::before {
    background: var(--amber);
    border-color: var(--amber);
  }

  .page-about .rail-node[data-active] {
    background: transparent;
  }

  .page-about .rail-node__year {
    display: block;
    font-size: 1.3rem;
    margin-bottom: 4px;
  }

  .page-about .rail-node__label {
    display: block;
    font-size: 11px;
    line-height: 1.5;
    letter-spacing: 0.06em;
  }

  .page-about .timeline__stages {
    gap: 22px;
  }

  .page-about .stage:nth-child(even) {
    margin-left: 48px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .stage,
  .page-about .flow__item,
  .page-about .flow__num,
  .page-about .rail-node,
  .page-about .rail-node::before,
  .page-about .close-links a,
  .page-about .close-links a::before {
    transition: none;
  }

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