.page-about {
  padding-top: calc(var(--top-h) + 18px);
  padding-bottom: 88px;
}

.page-about .breadcrumb {
  margin-bottom: 26px;
}

/* ---------- 首屏 ---------- */
.page-about .hero {
  padding-bottom: 24px;
}

.page-about .hero-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 30px;
  align-items: end;
}

.page-about .hero-lede h1 {
  font-family: var(--font-head);
  font-weight: 900;
  letter-spacing: -0.005em;
  line-height: 1.14;
  font-size: clamp(30px, 6vw, 62px);
  color: var(--paper);
  margin: 14px 0 20px;
}

.page-about .hero-lede h1 em {
  font-style: normal;
  color: var(--gold);
  font-family: var(--font-num);
  font-weight: 700;
  padding-inline: 2px;
}

.page-about .hero-p {
  font-size: clamp(15px, 1.1vw, 17px);
  line-height: 1.85;
  color: rgba(242, 239, 231, 0.82);
  max-width: var(--measure);
  margin: 0;
}

.page-about .hero-marks {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 22px;
  margin: 24px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .hero-marks li {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 14px;
  color: var(--stone);
}

.page-about .hero-media {
  margin: 0;
  position: relative;
}

.page-about .hero-media img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 14 / 9;
  object-fit: cover;
  border: 1px solid var(--line-strong);
  filter: saturate(0.92);
}

.page-about .hero-media::after {
  content: "";
  position: absolute;
  inset: 0;
  border-bottom: 3px solid var(--ice);
  pointer-events: none;
}

@media (min-width: 1024px) {
  .page-about .hero-grid {
    grid-template-columns: minmax(0, 5fr) minmax(0, 4fr);
    gap: 56px;
  }
  .page-about .hero-media {
    transform: translateY(-18px);
  }
}

/* ---------- 章节骨架 ---------- */
.page-about .section {
  padding-block: 54px;
}

@media (min-width: 900px) {
  .page-about .section {
    padding-block: 84px;
  }
  .page-about .hero {
    padding-bottom: 40px;
  }
}

.page-about .arc-head {
  max-width: 66ch;
  margin-bottom: 32px;
}

.page-about .arc-head .eyebrow,
.page-about .cat-main .eyebrow,
.page-about .team-text .eyebrow {
  color: var(--gold);
  letter-spacing: 0.08em;
}

.page-about .arc-title {
  font-family: var(--font-head);
  font-weight: 900;
  line-height: 1.18;
  font-size: clamp(24px, 3.4vw, 42px);
  color: var(--paper);
  margin: 10px 0 12px;
}

.page-about .arc-sub {
  font-size: clamp(15px, 1.05vw, 16.5px);
  line-height: 1.85;
  color: rgba(242, 239, 231, 0.72);
  margin: 0;
  max-width: 60ch;
}

/* ---------- 三件事 ---------- */
.page-about .role-list {
  border-top: 1px solid var(--line);
}

.page-about .role-item {
  display: grid;
  grid-template-columns: 1fr;
  gap: 10px;
  padding: 26px 0;
  border-bottom: 1px solid var(--line);
  border-left: 2px solid transparent;
  transition: border-color 180ms ease, background-color 180ms ease;
}

.page-about .role-item:hover {
  border-left-color: var(--ice);
  background-color: rgba(19, 28, 43, 0.55);
}

.page-about .role-idx {
  font-size: 26px;
  line-height: 1;
  color: var(--ice);
  font-weight: 700;
}

.page-about .role-title {
  font-family: var(--font-head);
  font-weight: 700;
  font-size: clamp(19px, 2vw, 24px);
  color: var(--paper);
  margin: 0;
}

.page-about .role-text p {
  margin: 0 0 12px;
  font-size: clamp(15px, 1.05vw, 16.5px);
  line-height: 1.85;
  color: rgba(242, 239, 231, 0.78);
  max-width: 56ch;
}

@media (min-width: 880px) {
  .page-about .role-item {
    grid-template-columns: 64px minmax(160px, 0.75fr) minmax(0, 1.6fr);
    gap: 0 28px;
    align-items: start;
    padding: 30px 18px;
  }
  .page-about .role-idx {
    padding-top: 4px;
  }
}

/* ---------- 时间轴 ---------- */
.page-about .tl {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .tl-node {
  position: relative;
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
  padding: 4px 0 34px 20px;
  border-left: 3px solid var(--clay);
}

.page-about .tl-node--current {
  border-left-color: var(--gold);
}

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

.page-about .tl-mark {
  display: flex;
  align-items: baseline;
  gap: 12px;
}

.page-about .tl-stage {
  font-size: 13px;
  letter-spacing: 0.1em;
  color: var(--clay);
  border: 1px solid currentColor;
  border-radius: 999px;
  padding: 3px 12px;
  white-space: nowrap;
}

.page-about .tl-node--current .tl-stage {
  color: var(--gold);
}

.page-about .tl-num {
  font-size: 20px;
  color: var(--stone);
  font-weight: 700;
}

.page-about .tl-node--current .tl-num {
  font-size: 28px;
  color: var(--gold);
}

.page-about .tl-body h3 {
  font-family: var(--font-head);
  font-weight: 700;
  font-size: clamp(18px, 1.9vw, 23px);
  color: var(--paper);
  margin: 0 0 10px;
}

.page-about .tl-body p {
  margin: 0;
  font-size: clamp(15px, 1.05vw, 16.5px);
  line-height: 1.85;
  color: rgba(242, 239, 231, 0.78);
  max-width: 58ch;
}

@media (min-width: 860px) {
  .page-about .tl-node {
    grid-template-columns: 148px minmax(0, 1fr);
    gap: 0 34px;
    padding: 4px 0 44px 26px;
  }
  .page-about .tl-mark {
    flex-direction: column;
    align-items: flex-start;
    gap: 10px;
    padding-top: 2px;
  }
  .page-about .tl-num {
    font-size: 32px;
  }
  .page-about .tl-node--current .tl-num {
    font-size: 48px;
    line-height: 0.95;
  }
}

/* ---------- 折叠详情 ---------- */
.page-about .collapse {
  margin-top: 14px;
}

.page-about .collapse summary {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  cursor: pointer;
  list-style: none;
  font-size: 14px;
  color: var(--gold);
  border-bottom: 1px dashed var(--gold-line);
  padding-bottom: 2px;
}

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

.page-about .collapse summary::after {
  content: "+";
  font-family: var(--font-num);
  line-height: 1;
}

.page-about .collapse[open] summary::after {
  content: "−";
}

.page-about .collapse-body {
  padding-top: 12px;
  border-left: 1px solid var(--line);
  padding-left: 14px;
  margin-left: 2px;
}

.page-about .collapse-body p {
  margin: 0;
  font-size: 15px;
  line-height: 1.85;
  color: rgba(242, 239, 231, 0.66);
  max-width: 56ch;
}

/* ---------- 分类带 ---------- */
.page-about .cat-band {
  margin-block: 22px;
  padding-block: clamp(34px, 5vw, 58px);
  border-top: 1px solid var(--line-strong);
  border-bottom: 1px solid var(--line-strong);
  background: linear-gradient(180deg, rgba(27, 79, 114, 0.42), rgba(11, 18, 32, 0) 78%),
    var(--panel);
}

.page-about .cat-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 34px;
}

.page-about .cat-main .arc-sub {
  max-width: 62ch;
}

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

.page-about .cat-media img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  border: 1px solid var(--line-strong);
}

@media (min-width: 1024px) {
  .page-about .cat-grid {
    grid-template-columns: minmax(0, 1.35fr) minmax(0, 1fr);
    gap: 48px;
    align-items: start;
  }
}

.page-about .tabs {
  margin-top: 26px;
}

.page-about .tablist {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 18px;
}

.page-about .tab {
  appearance: none;
  font: inherit;
  font-size: 14px;
  padding: 8px 18px;
  border-radius: 999px;
  border: 1px solid var(--line-strong);
  background: transparent;
  color: rgba(242, 239, 231, 0.72);
  cursor: pointer;
  transition: background-color 180ms ease, border-color 180ms ease, color 180ms ease;
}

.page-about .tab:hover {
  border-color: var(--ice);
  color: var(--paper);
}

.page-about .tab[aria-selected="true"] {
  background: var(--gold);
  border-color: var(--gold);
  color: var(--ink);
  font-weight: 700;
}

.page-about .tabpanel:focus-visible {
  outline: 2px solid var(--gold);
  outline-offset: 4px;
}

.page-about .cat-cells {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
  gap: 2px;
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .cat-cell {
  padding: 14px 16px;
  font-size: 15px;
  color: rgba(242, 239, 231, 0.8);
  background: rgba(11, 18, 32, 0.62);
  border: 1px solid var(--line);
}

.page-about .cat-cell--solid {
  background: var(--ice-deep);
  border-color: rgba(78, 168, 222, 0.55);
  color: var(--paper);
}

.page-about .cat-cells--fixed .cat-cell--fixed {
  display: flex;
  flex-direction: column;
  gap: 6px;
  border-left: 3px solid var(--gold);
  background: rgba(232, 180, 74, 0.08);
  color: var(--paper);
}

.page-about .cat-cell small {
  font-size: 12.5px;
  line-height: 1.6;
  color: var(--stone);
}

.page-about .cat-note {
  margin: 14px 0 0;
  font-size: 13.5px;
  color: var(--stone);
}

/* ---------- 团队 ---------- */
.page-about .team-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 30px;
}

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

.page-about .team-media img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 10 / 7;
  object-fit: cover;
  border: 1px solid var(--line-strong);
  border-top: 3px solid var(--moss);
}

.page-about .team-lead {
  font-size: clamp(15px, 1.05vw, 16.5px);
  line-height: 1.85;
  color: rgba(242, 239, 231, 0.78);
  max-width: 56ch;
  margin: 0 0 22px;
}

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

.page-about .team-roles li {
  padding: 20px 0 20px 18px;
  border-bottom: 1px solid var(--line);
  border-left: 2px solid var(--moss);
}

.page-about .team-roles h3 {
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 17px;
  color: var(--gold);
  margin: 0 0 8px;
}

.page-about .team-roles p {
  margin: 0;
  font-size: clamp(15px, 1.05vw, 16.5px);
  line-height: 1.85;
  color: rgba(242, 239, 231, 0.76);
  max-width: 56ch;
}

@media (min-width: 1000px) {
  .page-about .team-grid {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
    gap: 56px;
    align-items: start;
  }
  .page-about .team-media {
    position: sticky;
    top: calc(var(--top-h) + 24px);
  }
}

/* ---------- 规模数字 ---------- */
.page-about .stat-row {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  margin: 0;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .stat {
  background: var(--ink);
  padding: 26px 22px 24px;
}

.page-about .stat dt {
  font-size: 13.5px;
  letter-spacing: 0.06em;
  color: var(--stone);
  margin-bottom: 12px;
}

.page-about .stat dd {
  margin: 0 0 10px;
  display: flex;
  align-items: baseline;
  gap: 6px;
}

.page-about .stat-num {
  font-family: var(--font-num);
  font-weight: 700;
  font-size: clamp(42px, 7vw, 74px);
  line-height: 1;
  color: var(--gold);
}

.page-about .stat-unit {
  font-size: 15px;
  color: var(--ice);
}

.page-about .stat-note {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: rgba(242, 239, 231, 0.62);
}

@media (min-width: 780px) {
  .page-about .stat-row {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
  .page-about .stat {
    padding: 32px 28px 30px;
  }
}

/* ---------- 服务承诺 ---------- */
.page-about .promise-list {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: 1px solid var(--line);
}

.page-about .promise-row {
  display: grid;
  grid-template-columns: 1fr;
  gap: 8px;
  padding: 20px 16px;
  border-bottom: 1px solid var(--line);
}

.page-about .promise-row:nth-child(odd) {
  background: rgba(19, 28, 43, 0.5);
}

.page-about .promise-key {
  font-size: 14px;
  letter-spacing: 0.06em;
  color: var(--gold);
  border-left: 3px solid var(--gold);
  padding-left: 10px;
  line-height: 1.5;
}

.page-about .promise-val {
  font-size: clamp(15px, 1.05vw, 16.5px);
  line-height: 1.85;
  color: rgba(242, 239, 231, 0.78);
  max-width: 62ch;
}

@media (min-width: 820px) {
  .page-about .promise-row {
    grid-template-columns: 180px minmax(0, 1fr);
    gap: 0 34px;
    align-items: baseline;
    padding: 22px 20px;
  }
}

/* ---------- 认证与备案 ---------- */
.page-about .cert-block {
  border: 1px solid var(--line-strong);
  border-left: 4px solid var(--gold);
  background: linear-gradient(135deg, rgba(232, 180, 74, 0.12), rgba(11, 18, 32, 0) 62%),
    var(--panel);
  padding: clamp(24px, 4vw, 40px);
}

.page-about .cert-badge {
  display: inline-block;
  font-family: var(--font-num);
  font-size: 14px;
  letter-spacing: 0.06em;
  color: var(--ink);
  background: var(--gold);
  border-radius: 999px;
  padding: 6px 16px;
  margin: 0 0 18px;
}

.page-about .cert-text {
  margin: 0 0 24px;
  font-size: clamp(15px, 1.05vw, 16.5px);
  line-height: 1.85;
  color: rgba(242, 239, 231, 0.8);
  max-width: 58ch;
}

.page-about .cert-facts {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  margin: 0;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .cert-fact {
  background: var(--ink);
  padding: 18px 18px;
}

.page-about .cert-fact dt {
  font-size: 13px;
  letter-spacing: 0.06em;
  color: var(--stone);
  margin-bottom: 8px;
}

.page-about .cert-fact dd {
  margin: 0;
  font-size: 16px;
  color: var(--paper);
  word-break: break-word;
}

@media (min-width: 760px) {
  .page-about .cert-facts {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

/* ---------- 下一步 ---------- */
.page-about .next-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2px;
}

.page-about .next-card {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 22px 20px;
  text-decoration: none;
  border: 1px solid var(--line);
  background: var(--panel);
  transition: border-color 180ms ease, transform 180ms ease;
}

.page-about .next-card:hover {
  border-color: var(--ice);
  transform: translateX(4px);
}

.page-about .next-title {
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 17px;
  color: var(--paper);
}

.page-about .next-desc {
  font-size: 14px;
  line-height: 1.7;
  color: var(--stone);
}

.page-about .next-foot {
  margin: 22px 0 0;
  font-size: 14.5px;
  color: var(--stone);
}

.page-about .next-foot a {
  color: var(--gold);
  text-decoration: underline;
  text-underline-offset: 3px;
}

@media (min-width: 700px) {
  .page-about .next-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 1px;
    background: var(--line);
  }
}

@media (min-width: 1100px) {
  .page-about .next-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

/* ---------- 可访问性 ---------- */
.page-about a:focus-visible,
.page-about button:focus-visible,
.page-about summary:focus-visible {
  outline: 2px solid var(--gold);
  outline-offset: 3px;
}

@media (prefers-reduced-motion: reduce) {
  .page-about .role-item,
  .page-about .tab,
  .page-about .next-card {
    transition: none;
  }
  .page-about .hero-media {
    transform: none;
  }
  .page-about .next-card:hover {
    transform: none;
  }
}