.page-about {
  --ab-line: rgba(53, 224, 214, .30);
  --ab-line-soft: rgba(124, 140, 163, .26);
  --ab-surface: #0F2340;
  --ab-surface-2: #0B1B33;
  --ab-text: #C7D3E4;
  --ab-dim: #7C8CA3;
  color: var(--yf-cream);
  padding: 26px 0 88px;
}

/* ---------- 面包屑 ---------- */
.page-about .about-crumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  margin-bottom: 30px;
  font-family: var(--yf-mono);
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--ab-dim);
}
.page-about .about-crumbs .yf-crumbs__item {
  color: var(--ab-dim);
  text-decoration: none;
}
.page-about .about-crumbs .yf-crumbs__item + .yf-crumbs__item::before {
  content: "/";
  margin-right: 10px;
  color: var(--ab-line-soft);
}
.page-about .about-crumbs a.yf-crumbs__item:hover {
  color: var(--yf-cyan);
}
.page-about .about-crumbs .yf-crumbs__item[aria-current="page"] {
  color: var(--yf-cream);
}

/* ---------- 章节节奏 ---------- */
.page-about .about-block {
  margin-bottom: 64px;
}
.page-about .about-block:last-child,
.page-about .about-block--last {
  margin-bottom: 0;
}

/* ---------- 通用小标与标题 ---------- */
.page-about .about-kicker {
  margin: 0 0 14px;
  font-size: 12px;
  letter-spacing: .14em;
  color: var(--yf-cyan);
}
.page-about .about-kicker--dark {
  color: var(--yf-cyan);
}
.page-about .about-h2 {
  margin: 0 0 18px;
  font-size: clamp(1.55rem, 5.4vw, 2.3rem);
  font-weight: 800;
  line-height: 1.18;
  letter-spacing: -.01em;
}
.page-about .about-h2::after {
  content: "";
  display: block;
  width: 52px;
  height: 3px;
  margin-top: 16px;
  background: var(--yf-cyan);
}
.page-about .about-h3 {
  margin: 0 0 10px;
  font-size: 1.05rem;
  font-weight: 700;
  line-height: 1.45;
}
.page-about .about-sechead {
  margin-bottom: 26px;
}
.page-about .about-sechead--dark {
  margin-bottom: 28px;
}
.page-about .about-sechead__lead {
  max-width: 62ch;
  margin: 0;
  font-size: .97rem;
  line-height: 1.85;
  color: var(--ab-text);
}

/* ---------- 面板 ---------- */
.page-about .about-panel {
  padding: 30px 22px;
  border: 2px solid var(--ab-line-soft);
}
.page-about .about-panel--paper {
  background: var(--yf-cream);
  color: var(--yf-cocoa);
  border-color: var(--yf-cocoa);
  box-shadow: 10px 10px 0 rgba(27, 20, 16, .38);
}
.page-about .about-panel--paper .about-h2,
.page-about .about-panel--paper .about-h3 {
  color: var(--yf-cocoa);
}
.page-about .about-panel--paper .about-kicker {
  color: var(--yf-teal);
}
.page-about .about-panel--paper .about-h2::after {
  background: var(--yf-teal);
}
.page-about .about-panel--paper p {
  color: #3B3028;
}
.page-about .about-panel--ink {
  background: linear-gradient(155deg, #12294A 0%, #0B1B33 58%, #071223 100%);
  border-color: var(--ab-line);
  box-shadow: 12px 12px 0 rgba(53, 224, 214, .08);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero__grid {
  display: grid;
  gap: 34px;
}
.page-about .about-hero__title {
  margin: 0 0 20px;
  font-size: clamp(2.15rem, 8.4vw, 4.3rem);
  font-weight: 300;
  line-height: 1.05;
  letter-spacing: -.02em;
  color: var(--yf-cream);
}
.page-about .about-hero__lede {
  max-width: 54ch;
  margin: 0 0 30px;
  font-size: 1rem;
  line-height: 1.82;
  color: var(--ab-text);
}
.page-about .about-hero__facts {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(132px, 1fr));
  gap: 1px;
  margin: 0 0 30px;
  padding: 0;
  list-style: none;
  background: var(--ab-line-soft);
  border: 1px solid var(--ab-line-soft);
}
.page-about .about-fact {
  background: var(--ab-surface);
  padding: 16px 16px 15px;
}
.page-about .about-fact b {
  display: block;
  margin-bottom: 6px;
  font-family: var(--yf-mono);
  font-size: 1.45rem;
  font-weight: 500;
  line-height: 1.1;
  color: var(--yf-cyan);
}
.page-about .about-fact span {
  font-size: .78rem;
  letter-spacing: .04em;
  line-height: 1.5;
  color: var(--ab-dim);
}
.page-about .about-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}
.page-about .about-hero__media {
  margin: 0;
  border: 2px solid var(--ab-line);
  background: var(--ab-surface);
  box-shadow: var(--yf-shadow-hard);
}
.page-about .about-hero__media img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}
.page-about .about-hero__media .yf-media__caption {
  padding: 12px 16px;
  border-top: 1px solid var(--ab-line-soft);
  font-family: var(--yf-mono);
  font-size: 11px;
  letter-spacing: .06em;
  line-height: 1.6;
  color: var(--ab-dim);
}

/* ---------- 品牌主张 ---------- */
.page-about .about-claim__lead {
  max-width: 66ch;
  margin: 0;
  font-size: 1.02rem;
  line-height: 1.88;
  color: #3B3028;
}
.page-about .about-claim__cols {
  display: grid;
  gap: 24px;
  margin-top: 30px;
}
.page-about .about-claim__col {
  padding-top: 18px;
  border-top: 3px solid var(--yf-teal);
}
.page-about .about-claim__col p {
  margin: 0;
  font-size: .92rem;
  line-height: 1.82;
}

/* ---------- 时间线 ---------- */
.page-about .about-route__map {
  margin: 0 0 32px;
  border: 2px solid var(--ab-line-soft);
  background: var(--ab-surface-2);
}
.page-about .about-route__map img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}
.page-about .about-tl {
  display: grid;
  gap: 26px;
}
.page-about .about-tl__list {
  display: flex;
  gap: 10px;
  padding: 4px 2px 12px;
  overflow-x: auto;
  scrollbar-width: thin;
  -webkit-overflow-scrolling: touch;
}
.page-about .about-tl__node {
  position: relative;
  flex: 0 0 auto;
  display: flex;
  flex-direction: column;
  gap: 4px;
  min-width: 158px;
  padding: 14px 16px;
  background: rgba(255, 255, 255, .04);
  border: 2px solid transparent;
  color: inherit;
  font: inherit;
  text-align: left;
  cursor: pointer;
  transition: background .18s var(--yf-ease), border-color .18s var(--yf-ease), transform .18s var(--yf-ease);
}
.page-about .about-tl__node:hover {
  transform: translateY(-2px);
  background: rgba(53, 224, 214, .09);
}
.page-about .about-tl__node:focus-visible {
  outline: 2px solid var(--yf-cyan);
  outline-offset: 2px;
}
.page-about .about-tl__node[aria-selected="true"] {
  background: rgba(53, 224, 214, .12);
  border-color: var(--yf-cyan);
}
.page-about .about-tl__node i {
  font-style: normal;
  font-family: var(--yf-mono);
  font-size: 11px;
  letter-spacing: .12em;
  color: var(--yf-cyan);
}
.page-about .about-tl__node strong {
  font-size: .95rem;
  font-weight: 700;
  line-height: 1.35;
  color: var(--yf-cream);
}
.page-about .about-tl__node em {
  font-style: normal;
  font-family: var(--yf-mono);
  font-size: 10.5px;
  letter-spacing: .05em;
  line-height: 1.5;
  color: var(--ab-dim);
}
.page-about .about-tl__panels {
  display: grid;
  gap: 16px;
}
.page-about .about-tl__panel {
  padding: 24px 20px;
  background: rgba(255, 255, 255, .035);
  border: 2px solid var(--ab-line);
  border-left: 4px solid var(--yf-cyan);
}
.page-about .about-tl__panel h3 {
  margin: 0 0 12px;
  font-size: 1.12rem;
  font-weight: 700;
  line-height: 1.4;
  color: var(--yf-cream);
}
.page-about .about-tl__panel p {
  max-width: 62ch;
  margin: 0;
  font-size: .93rem;
  line-height: 1.85;
  color: var(--ab-text);
}
.page-about .about-tl__panel .about-kicker {
  margin: 0 0 8px;
}

/* ---------- 团队与研发 ---------- */
.page-about .about-team__figure {
  display: block;
  width: 100%;
  height: auto;
  margin: 0 0 30px;
  border: 2px solid var(--yf-cocoa);
  background: var(--ab-surface-2);
}
.page-about .about-team__roles {
  display: grid;
  gap: 18px;
}
.page-about .about-role {
  padding: 20px 18px;
  background: var(--yf-paper);
  border: 2px solid rgba(27, 20, 16, .22);
}
.page-about .about-role__icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  margin-bottom: 14px;
  background: var(--yf-ink);
  color: var(--yf-cyan);
}
.page-about .about-role__icon svg {
  display: block;
}
.page-about .about-role p {
  margin: 0;
  font-size: .9rem;
  line-height: 1.8;
  color: #3B3028;
}
.page-about .about-role__bar {
  height: 6px;
  margin: 16px 0 12px;
  background: rgba(27, 20, 16, .12);
}
.page-about .about-role__bar i {
  display: block;
  height: 100%;
  background: var(--yf-teal);
}
.page-about .about-role:nth-child(1) .about-role__bar i {
  width: 100%;
}
.page-about .about-role:nth-child(2) .about-role__bar i {
  width: 84%;
  background: var(--yf-cyan);
}
.page-about .about-role:nth-child(3) .about-role__bar i {
  width: 68%;
  background: var(--yf-amber);
}
.page-about .about-role .about-role__note {
  font-family: var(--yf-mono);
  font-size: 10.5px;
  letter-spacing: .04em;
  line-height: 1.7;
  color: #6B5B4C;
}

/* ---------- 交付步骤 ---------- */
.page-about .about-steps {
  display: grid;
  gap: 1px;
  margin: 0 0 24px;
  padding: 0;
  list-style: none;
  background: var(--ab-line-soft);
  border: 2px solid var(--ab-line-soft);
}
.page-about .about-step {
  background: var(--ab-surface);
  padding: 26px 22px;
}
.page-about .about-step__no {
  display: block;
  margin-bottom: 14px;
  font-family: var(--yf-mono);
  font-size: 11.5px;
  letter-spacing: .16em;
  color: var(--yf-amber);
}
.page-about .about-step h3 {
  margin: 0 0 10px;
  font-size: 1.05rem;
  font-weight: 700;
  line-height: 1.4;
  color: var(--yf-cream);
}
.page-about .about-step p {
  margin: 0;
  font-size: .9rem;
  line-height: 1.82;
  color: var(--ab-text);
}
.page-about .about-note {
  margin: 0;
  padding: 6px 0 6px 16px;
  border-left: 3px solid var(--yf-cyan);
  font-size: .9rem;
  line-height: 1.85;
  color: var(--ab-dim);
}
.page-about .about-note a {
  color: var(--yf-cyan);
  text-underline-offset: 4px;
}

/* ---------- 资质与生态 ---------- */
.page-about .about-stats {
  display: grid;
  gap: 1px;
  margin: 28px 0 0;
  background: var(--ab-line-soft);
  border: 2px solid var(--ab-line-soft);
}
.page-about .about-stat {
  background: var(--yf-night);
  padding: 26px 20px;
}
.page-about .about-stat b {
  display: block;
  font-size: clamp(2.1rem, 6.2vw, 3rem);
  font-weight: 300;
  line-height: 1;
  letter-spacing: -.02em;
  color: var(--yf-cream);
}
.page-about .about-stat b::after {
  content: "";
  display: block;
  width: 40px;
  height: 4px;
  margin-top: 14px;
  background: var(--yf-amber);
}
.page-about .about-stat span {
  display: block;
  margin-top: 12px;
  font-size: .85rem;
  line-height: 1.7;
  color: var(--ab-dim);
}
.page-about .about-cred__foot {
  max-width: 64ch;
  margin: 30px 0 0;
  font-size: .93rem;
  line-height: 1.85;
  color: var(--ab-text);
}

/* ---------- 为什么选择 ---------- */
.page-about .about-reasons {
  display: grid;
  gap: 18px;
}
.page-about .about-reason {
  padding: 24px 22px;
  background: linear-gradient(160deg, rgba(53, 224, 214, .07), rgba(11, 27, 51, .25));
  border: 2px solid var(--ab-line-soft);
  transition: transform .2s var(--yf-ease), box-shadow .2s var(--yf-ease);
}
.page-about .about-reason:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 0 -4px rgba(53, 224, 214, .16);
}
.page-about .about-reason h3 {
  margin: 0 0 10px;
  font-size: 1.08rem;
  font-weight: 700;
  line-height: 1.4;
  color: var(--yf-cream);
}
.page-about .about-reason p {
  margin: 0;
  font-size: .92rem;
  line-height: 1.82;
  color: var(--ab-text);
}

/* ---------- 页尾邀请 ---------- */
.page-about .about-cta {
  padding: 36px 24px;
  border: 2px solid var(--yf-amber);
  background: linear-gradient(135deg, rgba(255, 138, 61, .18), rgba(7, 18, 35, .62));
  box-shadow: 10px 10px 0 rgba(255, 138, 61, .14);
}
.page-about .about-cta__inner {
  max-width: 620px;
}
.page-about .about-cta__kicker {
  margin: 0 0 14px;
  font-size: 12px;
  letter-spacing: .16em;
  color: var(--yf-amber);
}
.page-about .about-cta__title {
  margin: 0 0 24px;
  font-size: clamp(1.35rem, 4.6vw, 2rem);
  font-weight: 300;
  line-height: 1.3;
  letter-spacing: -.01em;
  color: var(--yf-cream);
}

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

@media (min-width: 760px) {
  .page-about .about-panel {
    padding: 42px 38px;
  }
  .page-about .about-steps {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .page-about .about-claim__cols {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 22px;
  }
  .page-about .about-tl__panel {
    padding: 28px 26px;
  }
}

@media (min-width: 860px) {
  .page-about .about-team__roles {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
  .page-about .about-block {
    margin-bottom: 78px;
  }
}

/* ---------- 桌面：时间线两栏 + 节点轨道 ---------- */
@media (min-width: 900px) {
  .page-about .about-tl {
    grid-template-columns: minmax(0, 272px) minmax(0, 1fr);
    gap: 44px;
    align-items: start;
  }
  .page-about .about-tl__list {
    position: sticky;
    top: calc(var(--yf-top) + 20px);
    display: grid;
    gap: 2px;
    padding: 0 0 0 22px;
    overflow: visible;
  }
  .page-about .about-tl__list::before {
    content: "";
    position: absolute;
    left: 4px;
    top: 12px;
    bottom: 12px;
    width: 2px;
    background: linear-gradient(180deg, var(--yf-cyan), rgba(14, 139, 135, .22));
    opacity: .6;
  }
  .page-about .about-tl__node {
    min-width: 0;
  }
  .page-about .about-tl__node::before {
    content: "";
    position: absolute;
    left: -22px;
    top: 24px;
    width: 10px;
    height: 10px;
    background: var(--yf-cyan);
    box-shadow: 0 0 0 2px var(--yf-night);
  }
  .page-about .about-cta {
    padding: 46px 44px;
  }
}

/* ---------- 桌面：首屏分栏 ---------- */
@media (min-width: 1024px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 6.4fr) minmax(0, 5.6fr);
    gap: 56px;
    align-items: start;
  }
  .page-about .about-block {
    margin-bottom: 96px;
  }
  .page-about .about-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
  .page-about .about-reasons {
    grid-template-columns: repeat(12, minmax(0, 1fr));
    gap: 22px;
  }
  .page-about .about-reason:nth-child(1) {
    grid-column: 1 / span 7;
  }
  .page-about .about-reason:nth-child(2) {
    grid-column: 8 / span 5;
  }
  .page-about .about-reason:nth-child(3) {
    grid-column: 1 / span 5;
  }
  .page-about .about-reason:nth-child(4) {
    grid-column: 6 / span 7;
  }
}

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

/* ---------- 动效克制 ---------- */
@media (prefers-reduced-motion: reduce) {
  .page-about .about-tl__node,
  .page-about .about-reason {
    transition: none;
  }
  .page-about .about-tl__node:hover,
  .page-about .about-reason:hover {
    transform: none;
  }
}
</main>