.page-about {
  --about-gap: clamp(56px, 8vw, 104px);
  --about-radius: 18px;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-body);
  overflow-x: clip;
}

/* ---------- 面包屑 ---------- */
.page-about .breadcrumb {
  padding-top: clamp(20px, 3vw, 34px);
  margin-bottom: clamp(22px, 3vw, 36px);
}

.page-about .breadcrumb-list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: .5em;
  list-style: none;
  margin: 0;
  padding: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--rock);
}

.page-about .breadcrumb-list li + li::before {
  content: "/";
  margin-right: .5em;
  color: var(--rock);
}

.page-about .breadcrumb-link {
  color: var(--clay);
  text-decoration: none;
}

.page-about .breadcrumb-link:hover,
.page-about .breadcrumb-link:focus-visible {
  color: var(--ink);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.page-about .breadcrumb-current {
  color: var(--ink);
  font-weight: 600;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding-bottom: var(--about-gap);
  background: linear-gradient(158deg, var(--paper) 0%, var(--stone) 58%, var(--paper) 100%);
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  right: -12%;
  bottom: -70px;
  width: 62%;
  height: 150px;
  background: linear-gradient(90deg, transparent, var(--volt));
  opacity: .1;
  transform: rotate(-6deg);
  pointer-events: none;
}

.page-about .about-hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(28px, 4vw, 52px);
  align-items: start;
  position: relative;
  z-index: 1;
}

.page-about .eyebrow {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--clay);
  background: var(--stone);
  border: var(--line);
  border-radius: var(--r-capsule);
  padding: .45em 1.05em;
}

.page-about .about-hero h1 {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(32px, 6vw, 64px);
  line-height: 1.08;
  letter-spacing: -0.025em;
  margin: 20px 0 0;
  max-width: 20ch;
}

.page-about .about-lede {
  margin-top: 20px;
  max-width: 42ch;
  font-size: clamp(16px, 1.35vw, 18px);
  line-height: 1.82;
  color: var(--ink-soft);
}

.page-about .hero-facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px 20px;
  list-style: none;
  margin: 30px 0 0;
  padding: 24px 0 0;
  border-top: var(--line);
}

.page-about .hero-fact-num {
  display: block;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(22px, 3vw, 32px);
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--ink);
}

.page-about .hero-fact-label {
  display: block;
  margin-top: 8px;
  font-size: 13px;
  line-height: 1.5;
  color: var(--rock);
}

.page-about .hero-visual {
  position: relative;
  overflow: hidden;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  gap: 18px;
  min-height: clamp(230px, 30vw, 340px);
  padding: clamp(20px, 3vw, 32px);
  border: var(--line);
  border-radius: var(--about-radius);
  box-shadow: var(--shadow-hard-lg);
  background: linear-gradient(150deg, var(--coral) 0%, var(--volt) 62%, var(--ink) 100%);
  color: var(--white);
}

.page-about .hero-visual::before {
  content: "";
  position: absolute;
  inset: auto -25% -45% -25%;
  height: 72%;
  background: radial-gradient(circle at 42% 0, rgba(255, 255, 255, .3), transparent 62%);
  transform: rotate(-8deg);
  pointer-events: none;
}

.page-about .hero-visual-tag {
  position: relative;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .14em;
  color: rgba(255, 255, 255, .86);
}

.page-about .hero-visual-year {
  position: relative;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(58px, 11vw, 108px);
  line-height: .86;
  letter-spacing: -0.05em;
  color: var(--hi);
}

.page-about .hero-visual-lines {
  position: relative;
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.page-about .hero-visual-lines li {
  font-size: 13px;
  font-weight: 600;
  padding: 6px 12px;
  border-radius: var(--r-capsule);
  border: 1.5px solid rgba(255, 255, 255, .7);
  color: var(--white);
  background: rgba(30, 27, 38, .18);
}

/* ---------- 目录索引 ---------- */
.page-about .about-index {
  border-top: var(--line);
  border-bottom: var(--line);
  background: var(--stone);
}

.page-about .about-index-inner {
  display: flex;
  gap: 10px;
  overflow-x: auto;
  padding: 14px 0;
  -webkit-overflow-scrolling: touch;
}

.page-about .about-index-inner a {
  flex: 0 0 auto;
  font-size: 14px;
  font-weight: 600;
  text-decoration: none;
  color: var(--ink);
  background: var(--paper);
  border: var(--line);
  border-radius: var(--r-capsule);
  padding: 8px 16px;
  transition: background .2s var(--ease), color .2s var(--ease),
    box-shadow .2s var(--ease), transform .2s var(--ease);
}

.page-about .about-index-inner a:hover,
.page-about .about-index-inner a:focus-visible {
  background: var(--hi);
  box-shadow: var(--shadow-hard-sm);
  transform: translate(-2px, -2px);
}

.page-about .about-index-inner a[aria-current="true"] {
  background: var(--ink);
  border-color: var(--ink);
  color: var(--paper);
}

/* ---------- 通用分节 ---------- */
.page-about .about-block {
  padding: var(--about-gap) 0;
}

.page-about .about-block .section-head {
  max-width: 64ch;
  margin-bottom: clamp(30px, 4vw, 48px);
}

.page-about .section-head .h-editorial {
  font-family: var(--font-editorial);
  font-weight: 700;
  font-size: clamp(25px, 3.4vw, 42px);
  line-height: 1.26;
  letter-spacing: -0.01em;
  margin: 16px 0 0;
}

.page-about .section-head p {
  margin-top: 16px;
  font-size: clamp(15px, 1.25vw, 17px);
  line-height: 1.82;
  color: var(--ink-soft);
}

.page-about a:not(.breadcrumb-link):not(.footer-link) {
  color: var(--clay);
  text-decoration: underline;
  text-underline-offset: 3px;
  text-decoration-thickness: 1.5px;
  transition: color .18s var(--ease), text-decoration-color .18s var(--ease);
}

.page-about a:not(.breadcrumb-link):not(.footer-link):hover,
.page-about a:not(.breadcrumb-link):not(.footer-link):focus-visible {
  color: var(--volt);
}

/* ---------- 产品线演进 ---------- */
.page-about .about-lineage {
  background: var(--paper);
  position: relative;
}

.page-about .lineage-banner {
  margin: 0 0 clamp(32px, 4.5vw, 56px);
  border: var(--line);
  border-radius: var(--about-radius);
  box-shadow: var(--shadow-hard);
  overflow: hidden;
  transform: rotate(-1.1deg);
  background: var(--stone);
}

.page-about .lineage-banner img {
  display: block;
  width: 100%;
  height: clamp(180px, 26vw, 300px);
  object-fit: cover;
}

.page-about .tl {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(20px, 3vw, 34px);
}

.page-about .tl-rail {
  display: flex;
  gap: 8px;
  overflow-x: auto;
  padding-bottom: 4px;
}

.page-about .tl-rail a {
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: 15px;
  font-weight: 600;
  letter-spacing: .04em;
  text-decoration: none;
  color: var(--ink);
  background: var(--stone);
  border: var(--line);
  border-radius: var(--r-capsule);
  padding: 7px 15px;
  transition: background .2s var(--ease), color .2s var(--ease),
    box-shadow .2s var(--ease), transform .2s var(--ease);
}

.page-about .tl-rail a:hover,
.page-about .tl-rail a:focus-visible {
  background: var(--hi);
  box-shadow: var(--shadow-hard-sm);
  transform: translate(-2px, -2px);
}

.page-about .tl-rail a[aria-current="true"] {
  background: var(--volt);
  border-color: var(--ink);
  color: var(--white);
}

.page-about .tl-list {
  list-style: none;
  margin: 0;
  padding: 0 0 0 34px;
  position: relative;
}

.page-about .tl-list::before {
  content: "";
  position: absolute;
  left: 9px;
  top: 10px;
  bottom: 10px;
  width: 2px;
  border-radius: 2px;
  background: linear-gradient(180deg, var(--coral) 0%, var(--volt) 62%, var(--moss) 100%);
}

.page-about .tl-item {
  position: relative;
  padding-bottom: clamp(30px, 4vw, 46px);
  scroll-margin-top: 120px;
}

.page-about .tl-item:last-child {
  padding-bottom: 0;
}

.page-about .tl-dot {
  position: absolute;
  left: -34px;
  top: 6px;
  width: 20px;
  height: 20px;
  border-radius: 50%;
  border: var(--line);
  background: var(--paper);
}

.page-about .tl-item:nth-child(1) .tl-dot { background: var(--coral); }
.page-about .tl-item:nth-child(2) .tl-dot { background: var(--hi); }
.page-about .tl-item:nth-child(3) .tl-dot { background: var(--volt); }
.page-about .tl-item:nth-child(4) .tl-dot { background: var(--moss); }

.page-about .tl-year {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(26px, 3.6vw, 40px);
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--ink);
  margin: 0 0 10px;
}

.page-about .tl-title {
  font-family: var(--font-editorial);
  font-weight: 700;
  font-size: clamp(18px, 2vw, 24px);
  line-height: 1.4;
  margin: 0 0 12px;
  padding-bottom: 12px;
  border-bottom: var(--hair);
  transition: border-color .2s var(--ease), color .2s var(--ease);
}

.page-about .tl-item:hover .tl-title {
  border-bottom-color: var(--volt);
  color: var(--ink-soft);
}

.page-about .tl-text {
  margin: 0;
  max-width: 56ch;
  font-size: 16px;
  line-height: 1.82;
  color: var(--ink-soft);
}

.page-about .lineage-foot,
.page-about .quality-tail,
.page-about .rhythm-tail {
  margin-top: clamp(28px, 4vw, 44px);
  padding-top: 22px;
  border-top: var(--line);
  font-size: 15px;
  line-height: 1.8;
  color: var(--ink-soft);
  max-width: 66ch;
}

/* ---------- 服务网络 ---------- */
.page-about .about-network {
  background: var(--stone);
}

.page-about .net-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(28px, 4vw, 48px);
  align-items: start;
}

.page-about .net-map {
  border: var(--line);
  border-radius: var(--about-radius);
  box-shadow: var(--shadow-hard);
  background: var(--paper);
  padding: clamp(16px, 2.4vw, 28px);
}

.page-about .net-svg {
  display: block;
  width: 100%;
  height: auto;
}

.page-about .net-links line {
  stroke: var(--rock);
  stroke-width: 1.5;
  stroke-dasharray: 6 7;
  opacity: .5;
}

.page-about .net-node circle {
  fill: var(--paper);
  stroke: var(--ink);
  stroke-width: 2.5;
  transition: r .22s var(--ease), fill .22s var(--ease);
}

.page-about .net-node--main circle {
  fill: var(--coral);
}

.page-about .net-node text {
  font-family: var(--font-body);
  font-size: 17px;
  font-weight: 600;
  fill: var(--ink);
  opacity: .52;
  transition: opacity .22s var(--ease), fill .22s var(--ease);
}

.page-about .net-node:hover circle,
.page-about .net-node:focus circle {
  r: 17;
  fill: var(--volt);
}

.page-about .net-node:hover text,
.page-about .net-node:focus text {
  opacity: 1;
  fill: var(--clay);
}

.page-about .net-caption {
  margin: 14px 0 0;
  font-size: 13px;
  line-height: 1.7;
  color: var(--rock);
}

.page-about .net-stats {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 2px;
}

.page-about .net-stat {
  padding: 20px 0;
  border-top: var(--line);
}

.page-about .net-stat:last-child {
  border-bottom: var(--line);
}

.page-about .net-stat-num {
  display: block;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(28px, 4vw, 44px);
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--ink);
}

.page-about .net-stat-label {
  display: block;
  margin-top: 10px;
  font-size: 14px;
  line-height: 1.7;
  color: var(--ink-soft);
}

.page-about .net-note {
  margin-top: 24px;
}

.page-about .net-tail {
  margin: 22px 0 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--ink-soft);
}

/* ---------- 团队分工 ---------- */
.page-about .about-team {
  background: var(--paper);
}

.page-about .team-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(28px, 4vw, 52px);
  align-items: start;
}

.page-about .team-figure {
  margin: 0;
  border: var(--line);
  border-radius: var(--about-radius);
  box-shadow: var(--shadow-hard-lg);
  overflow: hidden;
  background: var(--stone);
  transform: rotate(-1.4deg);
}

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

.page-about .team-figure .media-caption {
  padding: 14px 18px;
  font-size: 13px;
  line-height: 1.65;
  color: var(--rock);
  background: var(--paper);
  border-top: var(--line);
}

.page-about .team-copy .h-editorial {
  font-family: var(--font-editorial);
  font-weight: 700;
  font-size: clamp(25px, 3.4vw, 40px);
  line-height: 1.26;
  letter-spacing: -0.01em;
  margin: 16px 0 0;
}

.page-about .team-copy > p:not(.eyebrow) {
  margin-top: 16px;
  font-size: 16px;
  line-height: 1.82;
  color: var(--ink-soft);
  max-width: 52ch;
}

.page-about .team-roles {
  list-style: none;
  margin: 28px 0 0;
  padding: 0;
  display: grid;
  gap: 14px;
}

.page-about .team-role {
  display: grid;
  gap: 6px;
  padding: 18px 20px;
  border: var(--line);
  border-radius: var(--r-card);
  background: var(--stone);
  transition: box-shadow .2s var(--ease), transform .2s var(--ease), background .2s var(--ease);
}

.page-about .team-role:hover {
  box-shadow: var(--shadow-hard-sm);
  transform: translate(-3px, -3px);
  background: var(--paper);
}

.page-about .role-name {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 16px;
  letter-spacing: -0.01em;
  color: var(--ink);
}

.page-about .role-desc {
  font-size: 14.5px;
  line-height: 1.78;
  color: var(--ink-soft);
}

/* ---------- 测试与质量 ---------- */
.page-about .about-quality {
  background: var(--ink);
  color: var(--paper);
}

.page-about .about-quality .eyebrow {
  color: var(--hi);
  background: transparent;
  border-color: var(--paper);
}

.page-about .about-quality .h-editorial {
  color: var(--paper);
}

.page-about .about-quality .section-head p {
  color: rgba(250, 246, 241, .76);
}

.page-about .quality-grid {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 18px;
}

.page-about .quality-item {
  padding: 24px 22px;
  border: 2px solid var(--paper);
  border-radius: var(--r-card);
  background: rgba(250, 246, 241, .04);
  transition: background .2s var(--ease), transform .2s var(--ease);
}

.page-about .quality-item:hover {
  background: rgba(255, 194, 75, .12);
  transform: translateY(-3px);
}

.page-about .quality-index {
  display: block;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 14px;
  letter-spacing: .12em;
  color: var(--hi);
}

.page-about .quality-title {
  font-family: var(--font-editorial);
  font-weight: 700;
  font-size: 21px;
  line-height: 1.35;
  margin: 12px 0 10px;
  color: var(--paper);
}

.page-about .quality-item p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.78;
  color: rgba(250, 246, 241, .78);
}

.page-about .about-quality .quality-tail {
  color: rgba(250, 246, 241, .8);
  border-top-color: rgba(250, 246, 241, .3);
}

/* ---------- 渠道与合作 ---------- */
.page-about .about-partners {
  background: var(--paper);
}

.page-about .partner-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(28px, 4vw, 50px);
  align-items: center;
}

.page-about .partner-copy .h-editorial {
  font-family: var(--font-editorial);
  font-weight: 700;
  font-size: clamp(25px, 3.4vw, 40px);
  line-height: 1.26;
  letter-spacing: -0.01em;
  margin: 16px 0 0;
}

.page-about .partner-copy > p:not(.eyebrow) {
  margin-top: 16px;
  font-size: 16px;
  line-height: 1.82;
  color: var(--ink-soft);
  max-width: 52ch;
}

.page-about .partner-facts {
  list-style: none;
  margin: 26px 0 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
}

.page-about .partner-facts li {
  flex: 1 1 160px;
  padding: 16px 18px;
  border: var(--line);
  border-radius: var(--r-card);
  background: var(--stone);
  box-shadow: var(--shadow-hard-sm);
}

.page-about .partner-num {
  display: block;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(24px, 3vw, 32px);
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--clay);
}

.page-about .partner-label {
  display: block;
  margin-top: 8px;
  font-size: 13.5px;
  line-height: 1.6;
  color: var(--ink-soft);
}

.page-about .partner-tail {
  margin-top: 22px;
  font-size: 15px;
  line-height: 1.8;
  color: var(--ink-soft);
  max-width: 52ch;
}

.page-about .partner-figure {
  margin: 0;
  border: var(--line);
  border-radius: var(--about-radius);
  box-shadow: var(--shadow-hard-lg);
  overflow: hidden;
  background: var(--stone);
}

.page-about .partner-figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 11 / 8;
  object-fit: cover;
}

.page-about .partner-figure .media-caption {
  padding: 14px 18px;
  font-size: 13px;
  line-height: 1.65;
  color: var(--rock);
  background: var(--paper);
  border-top: var(--line);
}

/* ---------- 年度节奏 ---------- */
.page-about .about-rhythm {
  background: var(--stone);
}

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

.page-about .rhythm-item {
  position: relative;
  padding: 26px 0 26px 22px;
  border-top: var(--line);
}

.page-about .rhythm-item:last-child {
  border-bottom: var(--line);
}

.page-about .rhythm-item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 34px;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--coral);
  border: 2px solid var(--ink);
}

.page-about .rhythm-item:nth-child(2)::before { background: var(--hi); }
.page-about .rhythm-item:nth-child(3)::before { background: var(--volt); }
.page-about .rhythm-item:nth-child(4)::before { background: var(--moss); }

.page-about .rhythm-cycle {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 13px;
  letter-spacing: .14em;
  color: var(--clay);
  margin: 0;
}

.page-about .rhythm-title {
  font-family: var(--font-editorial);
  font-weight: 700;
  font-size: clamp(19px, 2.2vw, 24px);
  line-height: 1.4;
  margin: 10px 0 10px;
  color: var(--ink);
}

.page-about .rhythm-text {
  margin: 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--ink-soft);
  max-width: 60ch;
}

/* ---------- 响应式 ---------- */
@media (min-width: 760px) {
  .page-about .hero-facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

  .page-about .quality-item:first-child {
    grid-column: 1 / -1;
  }

  .page-about .rhythm-item {
    display: grid;
    grid-template-columns: minmax(120px, 180px) minmax(0, 1fr);
    grid-template-areas:
      "cycle title"
      "cycle text";
    gap: 6px 26px;
    align-items: baseline;
    padding-left: 26px;
  }

  .page-about .rhythm-cycle {
    grid-area: cycle;
    padding-top: 6px;
  }

  .page-about .rhythm-title {
    grid-area: title;
    margin-top: 0;
  }

  .page-about .rhythm-text {
    grid-area: text;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero-grid {
    grid-template-columns: minmax(0, 1.4fr) minmax(0, 1fr);
    gap: clamp(36px, 5vw, 64px);
  }

  .page-about .tl {
    grid-template-columns: minmax(0, 132px) minmax(0, 1fr);
    gap: clamp(24px, 3vw, 40px);
  }

  .page-about .tl-rail {
    flex-direction: column;
    overflow: visible;
    position: sticky;
    top: 104px;
    align-self: start;
    padding-bottom: 0;
  }

  .page-about .tl-rail a {
    text-align: center;
    font-size: 17px;
  }

  .page-about .net-grid {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 1fr);
    gap: clamp(32px, 4vw, 56px);
  }

  .page-about .team-grid {
    grid-template-columns: minmax(0, 0.92fr) minmax(0, 1.08fr);
    align-items: center;
  }

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

  .page-about .quality-item:first-child {
    grid-column: auto;
  }

  .page-about .quality-item:nth-child(4) {
    grid-column: 1 / span 1;
  }

  .page-about .partner-grid {
    grid-template-columns: minmax(0, 1fr) minmax(0, 0.95fr);
  }
}

@media (min-width: 1120px) {
  .page-about .about-hero h1 {
    max-width: 18ch;
  }

  .page-about .quality-item {
    padding: 28px 24px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about *,
  .page-about *::before,
  .page-about *::after {
    transition-duration: .01ms !important;
    animation-duration: .01ms !important;
  }
}