.page-about {
  --about-sticky: calc(var(--header-h) + 14px);
  --about-gap: clamp(20px, 3vw, 32px);
  background: var(--ink);
  color: var(--cream);
}

/* ---------- 首屏 ---------- */

.page-about .about-hero {
  position: relative;
  overflow: hidden;
  border-bottom: 1px solid var(--line);
  isolation: isolate;
}

.page-about .about-hero__bg {
  position: absolute;
  inset: 0;
  z-index: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.3;
  filter: saturate(0.72) contrast(1.06);
}

.page-about .about-hero__veil {
  position: absolute;
  inset: 0;
  z-index: 1;
  background:
    linear-gradient(180deg, rgba(7, 20, 38, 0.7) 0%, rgba(7, 20, 38, 0.96) 100%),
    radial-gradient(58% 76% at 80% 16%, rgba(56, 225, 208, 0.18), transparent 70%),
    radial-gradient(52% 68% at 10% 88%, rgba(232, 180, 74, 0.13), transparent 72%);
}

.page-about .about-hero__veil::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(30, 58, 95, 0.42) 1px, transparent 1px),
    linear-gradient(90deg, rgba(30, 58, 95, 0.42) 1px, transparent 1px);
  background-size: 64px 64px;
  -webkit-mask-image: linear-gradient(180deg, rgba(0, 0, 0, 0.9), transparent 88%);
  mask-image: linear-gradient(180deg, rgba(0, 0, 0, 0.9), transparent 88%);
}

.page-about .about-hero__inner {
  position: relative;
  z-index: 2;
  display: grid;
  gap: 34px;
  padding-block: clamp(46px, 9vw, 104px);
}

.page-about .about-hero .breadcrumb {
  margin-bottom: 18px;
  font-size: 13px;
}

.page-about .about-hero h1 {
  margin: 14px 0 18px;
  font-family: var(--font-narrow);
  font-size: clamp(30px, 6.6vw, 54px);
  font-weight: 800;
  line-height: 1.14;
  letter-spacing: 0.05em;
  color: var(--cream);
}

.page-about .about-hero .lede {
  max-width: 60ch;
  font-size: clamp(15px, 2.1vw, 17px);
  line-height: 1.82;
  color: var(--muted);
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 28px;
}

.page-about .about-hero__panel {
  padding: 22px 22px 18px;
  border: 1px solid var(--line);
  background: linear-gradient(158deg, rgba(12, 31, 56, 0.92), rgba(7, 20, 38, 0.7));
  clip-path: polygon(0 0, calc(100% - 20px) 0, 100% 20px, 100% 100%, 20px 100%, 0 calc(100% - 20px));
}

.page-about .about-hero__stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 20px 14px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-hero__stats .stat__num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(24px, 5vw, 34px);
  line-height: 1.1;
  color: var(--cyan);
  letter-spacing: -0.01em;
}

.page-about .about-hero__stats .stat--gold .stat__num {
  color: var(--gold);
}

.page-about .about-hero__stats .stat__label {
  display: block;
  margin-top: 6px;
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--muted);
}

.page-about .about-hero__ver {
  margin: 20px 0 0;
  padding-top: 16px;
  border-top: 1px dashed var(--line);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--gold);
}

/* ---------- 章节索引 ---------- */

.page-about .about-index {
  position: sticky;
  top: var(--header-h);
  z-index: 15;
  background: rgba(7, 20, 38, 0.94);
  border-bottom: 1px solid var(--line);
}

.page-about .about-index__inner {
  display: flex;
  align-items: center;
  gap: 12px;
  padding-block: 10px;
}

.page-about .about-index__label {
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.2em;
  color: var(--gold);
}

.page-about .about-index__list {
  display: flex;
  gap: 2px;
  margin: 0;
  padding: 0;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: none;
  -ms-overflow-style: none;
}

.page-about .about-index__list::-webkit-scrollbar {
  display: none;
}

.page-about .about-index__list a {
  display: block;
  padding: 6px 12px;
  border: 1px solid transparent;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.02em;
  color: var(--muted);
  text-decoration: none;
  white-space: nowrap;
}

.page-about .about-index__list a:hover,
.page-about .about-index__list a:focus-visible {
  color: var(--cyan-soft);
  border-color: var(--line);
  background: rgba(56, 225, 208, 0.07);
}

/* ---------- 章节通用 ---------- */

.page-about .section {
  padding-block: var(--space-section);
  scroll-margin-top: calc(var(--header-h) + 72px);
}

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

.page-about .section__head {
  max-width: 62ch;
}

.page-about .section__head h2 {
  margin: 12px 0 0;
  letter-spacing: 0.04em;
}

/* ---------- 品牌起点 ---------- */

.page-about .about-origin__grid {
  display: grid;
  gap: var(--about-gap);
  margin-top: 30px;
}

.page-about .about-origin__body p {
  margin: 0 0 16px;
  font-size: 15px;
  line-height: 1.88;
  color: var(--muted);
}

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

.page-about .about-origin__points li {
  padding: 4px 0 4px 16px;
  border-left: 2px solid var(--cyan);
  font-size: 15px;
  line-height: 1.72;
  color: var(--cream);
}

.page-about .about-origin__points strong {
  display: block;
  margin-bottom: 4px;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.14em;
  color: var(--cyan-soft);
}

/* ---------- 服务人群 ---------- */

.page-about .about-audience__grid {
  display: grid;
  gap: 20px;
  margin-top: 30px;
}

.page-about .about-audience__card {
  padding: 24px 22px;
}

.page-about .about-audience__num {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.24em;
  color: var(--magenta);
}

.page-about .about-audience__card h3 {
  margin: 0 0 12px;
  font-size: 18px;
  line-height: 1.4;
  letter-spacing: 0.03em;
  color: var(--cream);
}

.page-about .about-audience__card > p {
  margin: 0 0 16px;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--muted);
}

.page-about .about-audience__list {
  display: grid;
  gap: 8px;
  margin: 0 0 18px;
  padding: 0;
  list-style: none;
}

.page-about .about-audience__list li {
  position: relative;
  padding-left: 16px;
  font-size: 13.5px;
  line-height: 1.7;
  color: var(--cream);
}

.page-about .about-audience__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.72em;
  width: 6px;
  height: 1px;
  background: var(--cyan);
}

/* ---------- 三条主线 ---------- */

.page-about .about-paths__intro {
  margin: 16px 0 0;
  font-size: 15px;
  line-height: 1.85;
  color: var(--muted);
}

.page-about .about-paths__map {
  display: block;
  width: 100%;
  height: auto;
  max-height: 200px;
  margin: 28px 0 26px;
}

.page-about .about-paths__map path {
  fill: none;
  stroke: var(--line);
  stroke-width: 1.4;
}

.page-about .about-paths__map .p-main {
  stroke: var(--cyan);
  stroke-width: 1.8;
}

.page-about .about-paths__map .p-a {
  stroke: var(--cyan);
}

.page-about .about-paths__map .p-b {
  stroke: var(--gold);
}

.page-about .about-paths__map .p-c {
  stroke: var(--magenta);
}

.page-about .about-paths__map circle {
  stroke: var(--ink);
  stroke-width: 2;
}

.page-about .about-paths__map .n-main {
  fill: var(--cyan);
}

.page-about .about-paths__map .n-a {
  fill: var(--cyan);
}

.page-about .about-paths__map .n-b {
  fill: var(--gold);
}

.page-about .about-paths__map .n-c {
  fill: var(--magenta);
}

.page-about .about-paths__map text {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.06em;
}

.page-about .about-paths__map .t-main {
  fill: var(--cyan-soft);
}

.page-about .about-paths__map .t-a {
  fill: var(--cyan);
}

.page-about .about-paths__map .t-b {
  fill: var(--gold);
}

.page-about .about-paths__map .t-c {
  fill: var(--magenta);
}

.page-about .about-paths__tabs .tabs__list {
  display: flex;
  gap: 6px;
  overflow-x: auto;
  padding-bottom: 6px;
  border-bottom: 1px solid var(--line);
  scrollbar-width: none;
}

.page-about .about-paths__tabs .tabs__list::-webkit-scrollbar {
  display: none;
}

.page-about .about-paths__tabs .tab {
  flex: 0 0 auto;
  padding: 10px 16px;
  border: 1px solid transparent;
  border-bottom-width: 2px;
  background: transparent;
  font-family: var(--font-narrow);
  font-size: 14px;
  letter-spacing: 0.06em;
  color: var(--muted);
  white-space: nowrap;
  cursor: pointer;
}

.page-about .about-paths__tabs .tab[aria-selected="true"] {
  color: var(--cyan-soft);
  border-bottom-color: var(--cyan);
  background: rgba(56, 225, 208, 0.07);
}

.page-about .about-paths__pane {
  padding-top: 26px;
}

.page-about .about-paths__pane[hidden] {
  display: none;
}

.page-about .about-paths__pane h3 {
  margin: 0 0 12px;
  font-size: 19px;
  letter-spacing: 0.04em;
  color: var(--cream);
}

.page-about .about-paths__pane > p {
  max-width: 62ch;
  margin: 0 0 16px;
  font-size: 15px;
  line-height: 1.85;
  color: var(--muted);
}

.page-about .about-paths__list {
  display: grid;
  gap: 10px;
  margin: 0 0 22px;
  padding: 0;
  list-style: none;
}

.page-about .about-paths__list li {
  padding: 10px 14px;
  border-left: 2px solid var(--line);
  background: rgba(12, 31, 56, 0.6);
  font-family: var(--font-mono);
  font-size: 13px;
  line-height: 1.7;
  color: var(--cream);
}

/* ---------- 版本历程 ---------- */

.page-about .about-timeline__figure {
  margin: 30px 0 40px;
}

.page-about .about-timeline__body {
  display: grid;
  gap: 22px;
}

.page-about .about-timeline__rail {
  display: flex;
  gap: 16px;
  margin: 0;
  padding: 0 0 8px;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: none;
  -ms-overflow-style: none;
}

.page-about .about-timeline__rail::-webkit-scrollbar {
  display: none;
}

.page-about .about-timeline__rail li {
  flex: 0 0 auto;
  padding: 0 0 5px;
  border-bottom: 2px solid var(--line);
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: 0.08em;
  color: var(--gold);
  white-space: nowrap;
}

.page-about .about-timeline__rail li.is-current {
  border-bottom-color: var(--cyan);
  color: var(--cyan-soft);
}

.page-about .about-timeline__list .acc-item {
  margin-bottom: 10px;
  border: 1px solid var(--line);
  background: var(--ink-2);
}

.page-about .about-timeline__list .acc-trigger {
  display: flex;
  align-items: center;
  gap: 14px;
  width: 100%;
  padding: 15px 16px;
  border: 0;
  background: transparent;
  font-family: var(--font-sans);
  font-size: 15px;
  line-height: 1.6;
  letter-spacing: 0.02em;
  text-align: left;
  color: var(--cream);
  cursor: pointer;
}

.page-about .about-timeline__ver {
  flex: 0 0 auto;
  min-width: 42px;
  font-family: var(--font-mono);
  font-size: 15px;
  letter-spacing: 0.08em;
  color: var(--gold);
}

.page-about .about-timeline__ver--now {
  color: var(--cyan);
}

.page-about .about-timeline__list .acc-panel {
  padding: 0 16px 18px 16px;
}

.page-about .about-timeline__list .acc-panel p {
  margin: 0;
  padding-top: 14px;
  border-top: 1px dashed var(--line);
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--muted);
}

/* ---------- 编辑团队 ---------- */

.page-about .about-team__grid {
  display: grid;
  gap: 32px;
}

.page-about .about-team__body h2 {
  margin: 12px 0 18px;
  letter-spacing: 0.04em;
}

.page-about .about-team__body > p {
  margin: 0 0 24px;
  font-size: 15px;
  line-height: 1.88;
  color: var(--muted);
}

.page-about .about-team__groups {
  display: grid;
  gap: 16px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-team__groups li {
  display: grid;
  gap: 8px;
  padding-bottom: 14px;
  border-bottom: 1px dashed var(--line);
  font-size: 14.5px;
  line-height: 1.75;
  color: var(--cream);
}

.page-about .about-team__figure {
  margin: 0;
}

/* ---------- 资质与响应 ---------- */

.page-about .about-trust__grid {
  display: grid;
  gap: 18px;
  margin-top: 30px;
}

.page-about .about-trust__cert {
  padding: 22px 20px;
}

.page-about .about-trust__value {
  margin: 12px 0 0;
  font-family: var(--font-mono);
  font-size: clamp(17px, 3.4vw, 22px);
  letter-spacing: 0.04em;
  line-height: 1.5;
  color: var(--gold);
  word-break: break-word;
}

.page-about .about-trust__note {
  margin: 10px 0 0;
  font-size: 13.5px;
  line-height: 1.75;
  color: var(--muted);
}

.page-about .about-copy {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  margin-top: 16px;
  padding-top: 14px;
  border-top: 1px dashed var(--line);
}

.page-about .about-copy__key {
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--muted);
}

.page-about .about-copy__val {
  font-family: var(--font-mono);
  font-size: 14px;
  letter-spacing: 0.02em;
  color: var(--cream);
  word-break: break-all;
}

.page-about .about-trust__contact {
  display: grid;
  gap: 6px;
  margin-top: 34px;
  padding: 26px 22px;
  border: 1px solid var(--line);
  background: linear-gradient(150deg, rgba(12, 31, 56, 0.85), rgba(7, 20, 38, 0.55));
  clip-path: polygon(0 0, calc(100% - 22px) 0, 100% 22px, 100% 100%, 22px 100%, 0 calc(100% - 22px));
}

.page-about .about-trust__ctitle {
  margin: 0 0 12px;
  font-size: 19px;
  letter-spacing: 0.04em;
  color: var(--cream);
}

.page-about .about-trust__ctext {
  max-width: 68ch;
  margin: 0 0 12px;
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--muted);
}

.page-about .about-trust__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 18px;
}

/* ---------- 响应式 ---------- */

@media (min-width: 640px) {
  .page-about .about-hero__stats {
    gap: 22px 18px;
  }
}

@media (min-width: 820px) {
  .page-about .about-hero__inner {
    grid-template-columns: minmax(0, 1.4fr) minmax(280px, 0.75fr);
    align-items: end;
    gap: 48px;
  }

  .page-about .about-audience__grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 24px;
    align-items: start;
  }

  .page-about .about-audience__grid > :nth-child(2) {
    margin-top: 36px;
  }

  .page-about .about-audience__grid > :nth-child(3) {
    margin-top: 72px;
  }

  .page-about .about-trust__grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 22px;
  }

  .page-about .about-origin__grid {
    grid-template-columns: minmax(0, 1.35fr) minmax(0, 0.9fr);
    gap: 56px;
    align-items: start;
  }
}

@media (min-width: 900px) {
  .page-about .about-timeline__body {
    grid-template-columns: 172px minmax(0, 1fr);
    gap: 44px;
  }

  .page-about .about-timeline__rail {
    position: sticky;
    top: var(--about-sticky);
    align-self: start;
    flex-direction: column;
    gap: 14px;
    padding-bottom: 0;
    overflow: visible;
  }

  .page-about .about-timeline__rail li {
    padding: 0 0 0 10px;
    border-bottom: 0;
    border-left: 2px solid var(--line);
    line-height: 1.5;
  }

  .page-about .about-timeline__rail li.is-current {
    border-left-color: var(--cyan);
  }

  .page-about .about-timeline__list .acc-trigger {
    padding: 17px 20px;
  }

  .page-about .about-timeline__list .acc-panel {
    padding: 0 20px 20px;
  }

  .page-about .about-team__grid {
    grid-template-columns: minmax(0, 1.1fr) minmax(0, 0.9fr);
    gap: 56px;
    align-items: center;
  }

  .page-about .about-paths__map {
    max-height: 220px;
  }
}

@media (min-width: 1080px) {
  .page-about .about-copy__val {
    font-size: 15px;
  }

  .page-about .about-paths__pane {
    padding-top: 32px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-index__list a,
  .page-about .about-paths__tabs .tab {
    transition: none;
  }
}