.page-about {
  display: block;
  position: relative;
  background:
    radial-gradient(1100px 520px at 84% -6%, rgba(79, 195, 217, .13), transparent 62%),
    radial-gradient(760px 460px at 4% 8%, rgba(242, 193, 78, .07), transparent 66%),
    var(--c-space);
  color: var(--c-white);
  overflow-x: hidden;
}

/* ---------- 面包屑 ---------- */
.page-about .about-crumb {
  padding-top: clamp(22px, 4vw, 44px);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding: clamp(26px, 4.5vw, 60px) 0 clamp(44px, 6vw, 88px);
}

.page-about .about-hero__grid {
  display: grid;
  gap: clamp(28px, 4vw, 52px);
  align-items: center;
}

.page-about .about-hero__title {
  margin: .6rem 0 1.1rem;
  font-size: clamp(32px, 6.4vw, 72px);
  line-height: 1.08;
  font-weight: 800;
  letter-spacing: -0.01em;
  max-width: 15em;
}

.page-about .about-hero__lead {
  max-width: 36em;
  margin: 0;
  font-size: clamp(15.5px, 1.1vw, 18px);
  line-height: 1.78;
  color: var(--c-muted);
}

.page-about .about-facts {
  list-style: none;
  margin: 1.7rem 0 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 9px;
}

.page-about .about-facts li {
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
  padding: 7px 14px;
  border: 1px solid var(--c-line);
  background: rgba(22, 32, 74, .55);
  clip-path: polygon(0 0, calc(100% - 9px) 0, 100% 9px, 100% 100%, 9px 100%, 0 calc(100% - 9px));
  font-size: 13px;
  color: var(--c-muted);
  white-space: nowrap;
}

.page-about .about-facts b {
  font-family: var(--font-mono);
  font-size: 17px;
  font-weight: 600;
  color: var(--c-gold);
  font-variant-numeric: tabular-nums;
}

.page-about .about-hero__visual {
  position: relative;
  margin: 0;
  order: -1;
}

.page-about .about-hero__visual img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  opacity: .58;
  filter: saturate(.92) contrast(1.06);
  clip-path: polygon(0 0, calc(100% - 24px) 0, 100% 24px, 100% 100%, 24px 100%, 0 calc(100% - 24px));
}

.page-about .about-hero__visual::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background: linear-gradient(206deg, rgba(11, 18, 48, 0) 34%, rgba(6, 10, 30, .86) 100%);
  clip-path: polygon(0 0, calc(100% - 24px) 0, 100% 24px, 100% 100%, 24px 100%, 0 calc(100% - 24px));
}

.page-about .about-hero__anno {
  position: absolute;
  right: 4px;
  bottom: 14px;
  writing-mode: vertical-rl;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .24em;
  color: var(--c-muted);
  opacity: .72;
  z-index: 2;
}

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: 1.08fr .92fr;
    gap: clamp(40px, 5vw, 76px);
  }
  .page-about .about-hero__visual {
    order: 0;
  }
}

/* ---------- 通用小标题 ---------- */
.page-about .about-lede {
  max-width: 40em;
  margin: .9rem 0 0;
  font-size: 16px;
  line-height: 1.78;
  color: var(--c-muted);
}

.page-about h2 {
  margin: .5rem 0 0;
  font-size: clamp(23px, 3.2vw, 34px);
  line-height: 1.3;
  font-weight: 800;
  letter-spacing: -0.005em;
}

/* ---------- 时间轨道 ---------- */
.page-about .about-timeline {
  border-top: 1px solid rgba(42, 53, 96, .55);
}

.page-about .about-track {
  position: relative;
  list-style: none;
  margin: clamp(34px, 4.5vw, 58px) 0 0;
  padding: 0;
}

.page-about .about-track::before {
  content: "";
  position: absolute;
  left: 15px;
  top: 10px;
  bottom: 10px;
  width: 2px;
  background: linear-gradient(180deg, var(--c-cyan) 0%, var(--c-gold) 46%, rgba(42, 53, 96, .25) 100%);
  opacity: .6;
}

.page-about .about-track__item {
  position: relative;
  padding: 0 0 2.6rem 3rem;
}

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

.page-about .about-track__dot {
  position: absolute;
  left: 8px;
  top: .3rem;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--c-space);
  border: 2px solid var(--c-cyan);
  box-shadow: 0 0 0 5px rgba(79, 195, 217, .1);
  transition: border-color .3s var(--ease), box-shadow .3s var(--ease);
}

.page-about .about-track__mark {
  display: block;
  margin-bottom: .45rem;
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: .16em;
  color: var(--c-gold);
  font-variant-numeric: tabular-nums;
}

.page-about .about-track__title {
  margin: 0 0 .35rem;
  font-size: 18px;
  font-weight: 700;
  line-height: 1.4;
  transition: color .3s var(--ease);
}

.page-about .about-track__body p {
  margin: 0;
  max-width: 38em;
  font-size: 15.5px;
  line-height: 1.8;
  color: var(--c-muted);
}

@media (hover: hover) {
  .page-about .about-track__item:hover .about-track__title {
    color: var(--c-gold);
  }
  .page-about .about-track__item:hover .about-track__dot {
    border-color: var(--c-gold);
    box-shadow: 0 0 0 6px rgba(242, 193, 78, .13);
  }
}

@media (min-width: 900px) {
  .page-about .about-track::before {
    left: 147px;
  }
  .page-about .about-track__item {
    display: grid;
    grid-template-columns: 116px minmax(0, 1fr);
    column-gap: 60px;
    padding: 0 0 3.6rem 0;
  }
  .page-about .about-track__item:last-child {
    padding-bottom: 0;
  }
  .page-about .about-track__dot {
    left: 140px;
    top: .45rem;
  }
  .page-about .about-track__mark {
    text-align: right;
    padding-top: .35em;
    margin-bottom: 0;
  }
  .page-about .about-track__title {
    margin-top: -.15rem;
  }
}

/* ---------- 内容生产流程 ---------- */
.page-about .about-flow-section {
  border-top: 1px solid rgba(42, 53, 96, .55);
}

.page-about .about-flow__wrap {
  display: grid;
  gap: clamp(30px, 4vw, 60px);
}

.page-about .about-flow__figure {
  margin: clamp(24px, 3vw, 34px) 0 0;
}

.page-about .about-flow__figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  opacity: .5;
  clip-path: polygon(0 0, calc(100% - 20px) 0, 100% 20px, 100% 100%, 20px 100%, 0 calc(100% - 20px));
}

.page-about .about-flow {
  display: grid;
  gap: 12px;
  align-content: start;
}

.page-about .about-flow__step {
  position: relative;
  border: 1px solid var(--c-line);
  background: rgba(22, 32, 74, .42);
  transition: background-color .3s var(--ease), border-color .3s var(--ease);
}

.page-about .about-flow__step::before {
  content: "";
  position: absolute;
  left: -1px;
  top: 0;
  bottom: 0;
  width: 3px;
  background: var(--c-cyan);
  opacity: .7;
  transition: background-color .3s var(--ease), opacity .3s var(--ease);
}

.page-about .about-flow__step[open] {
  background: rgba(22, 32, 74, .82);
  border-color: rgba(42, 53, 96, .9);
}

.page-about .about-flow__step[open]::before {
  background: var(--c-gold);
  opacity: 1;
}

.page-about .about-flow__summary {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 17px 20px 17px 24px;
  cursor: pointer;
  list-style: none;
}

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

.page-about .about-flow__idx {
  flex: none;
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: .12em;
  color: var(--c-cyan);
  font-variant-numeric: tabular-nums;
  transition: color .3s var(--ease);
}

.page-about .about-flow__step[open] .about-flow__idx {
  color: var(--c-gold);
}

.page-about .about-flow__name {
  font-size: 17px;
  font-weight: 700;
  color: var(--c-white);
}

.page-about .about-flow__chev {
  flex: none;
  margin-left: auto;
  width: 9px;
  height: 9px;
  border-right: 2px solid var(--c-muted);
  border-bottom: 2px solid var(--c-muted);
  transform: rotate(45deg);
  transition: transform .3s var(--ease), border-color .3s var(--ease);
}

.page-about .about-flow__step[open] .about-flow__chev {
  transform: rotate(-135deg);
  border-color: var(--c-gold);
}

.page-about .about-flow__body {
  padding: 0 20px 20px 24px;
}

.page-about .about-flow__body p {
  margin: 0;
  max-width: 40em;
  font-size: 15.5px;
  line-height: 1.8;
  color: var(--c-muted);
}

.page-about .about-flow__out {
  display: inline-block;
  margin-top: 13px;
  padding: 5px 10px;
  border: 1px dashed var(--c-line);
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .08em;
  color: var(--c-muted);
}

@media (min-width: 1000px) {
  .page-about .about-flow__wrap {
    grid-template-columns: minmax(0, .85fr) minmax(0, 1.15fr);
    align-items: start;
  }
}

/* ---------- 团队 ---------- */
.page-about .about-team-section {
  border-top: 1px solid rgba(42, 53, 96, .55);
}

.page-about .about-team {
  display: grid;
  gap: 14px;
  margin-top: clamp(28px, 3.5vw, 46px);
}

.page-about .about-team__card {
  position: relative;
  overflow: hidden;
  padding: 26px 22px 28px;
  border: 1px solid var(--c-line);
  background: linear-gradient(163deg, rgba(22, 32, 74, .92) 0%, rgba(6, 10, 30, .9) 100%);
  clip-path: polygon(0 0, calc(100% - 18px) 0, 100% 18px, 100% 100%, 0 100%);
}

.page-about .about-team__card::after {
  content: "";
  position: absolute;
  right: -46px;
  top: -46px;
  width: 130px;
  height: 130px;
  border-radius: 50%;
  border: 1px solid rgba(79, 195, 217, .22);
  pointer-events: none;
}

.page-about .about-team__num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(42px, 6vw, 58px);
  line-height: 1;
  font-weight: 600;
  color: var(--c-gold);
  font-variant-numeric: tabular-nums;
  letter-spacing: -0.02em;
}

.page-about .about-team__unit {
  margin-left: 6px;
  font-family: var(--font-sans);
  font-size: 14px;
  font-weight: 500;
  letter-spacing: 0;
  color: var(--c-muted);
}

.page-about .about-team__name {
  margin: 14px 0 10px;
  font-size: 18px;
  font-weight: 700;
}

.page-about .about-team__card p {
  margin: 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--c-muted);
}

.page-about .about-team__figure {
  margin: clamp(30px, 4vw, 52px) 0 0;
}

.page-about .about-team__figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  opacity: .55;
  clip-path: polygon(0 0, calc(100% - 22px) 0, 100% 22px, 100% 100%, 22px 100%, 0 calc(100% - 22px));
}

.page-about .about-team__figure figcaption {
  margin-top: 12px;
  font-size: 13px;
  line-height: 1.7;
  color: var(--c-muted);
}

@media (min-width: 760px) {
  .page-about .about-team {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .page-about .about-team__card--wide {
    grid-column: span 2;
  }
}

@media (min-width: 1100px) {
  .page-about .about-team {
    grid-template-columns: 1.12fr 1fr .96fr;
  }
  .page-about .about-team__card--wide {
    grid-column: auto;
  }
}

/* ---------- 数据来源 ---------- */
.page-about .about-source-section {
  border-top: 1px solid rgba(42, 53, 96, .55);
}

.page-about .about-source__grid {
  display: grid;
  gap: clamp(26px, 3.5vw, 48px);
}

.page-about .about-source__copy p {
  margin: 1rem 0 0;
  max-width: 38em;
  font-size: 15.5px;
  line-height: 1.82;
  color: var(--c-muted);
}

.page-about .about-source__list {
  list-style: none;
  margin: 1.6rem 0 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 10px 22px;
}

.page-about .about-source__list li {
  font-size: 14px;
  color: var(--c-muted);
}

.page-about .about-source__list b {
  font-family: var(--font-mono);
  font-size: 16px;
  font-weight: 600;
  color: var(--c-cyan);
  font-variant-numeric: tabular-nums;
  margin-right: 6px;
}

.page-about .about-source__panel {
  padding: 24px 22px 26px;
  border: 1px solid var(--c-line);
  background: rgba(22, 32, 74, .5);
  border-top: 2px solid var(--c-cyan);
}

.page-about .about-source__panel-title {
  margin: 0 0 16px;
  font-size: 16px;
  font-weight: 700;
  letter-spacing: .02em;
}

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

.page-about .about-source__chain li {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding-bottom: 10px;
  border-bottom: 1px dashed rgba(42, 53, 96, .8);
  font-size: 14.5px;
  color: var(--c-white);
}

.page-about .about-source__chain li:last-child {
  border-bottom: none;
  padding-bottom: 0;
}

.page-about .about-source__chain .mono {
  flex: none;
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--c-gold);
}

.page-about .about-source__note {
  margin: 18px 0 0;
  font-size: 13px;
  line-height: 1.75;
  color: var(--c-muted);
}

@media (min-width: 1000px) {
  .page-about .about-source__grid {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, .85fr);
    align-items: start;
  }
}

/* ---------- 覆盖范围 ---------- */
.page-about .about-coverage {
  border-top: 1px solid rgba(42, 53, 96, .55);
}

.page-about .about-coverage__grid {
  display: grid;
  gap: clamp(26px, 3.5vw, 48px);
  margin-top: clamp(28px, 3.5vw, 44px);
  align-items: center;
}

.page-about .about-dots {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(8, 12px);
  gap: 9px;
  justify-content: start;
}

.page-about .about-dots li {
  width: 12px;
  height: 12px;
  background: rgba(79, 195, 217, .4);
  border: 1px solid rgba(79, 195, 217, .68);
}

.page-about .about-dots li.is-focus {
  background: var(--c-signal);
  border-color: var(--c-signal);
  box-shadow: 0 0 0 5px rgba(255, 106, 43, .16);
}

.page-about .about-coverage__legend {
  display: grid;
  gap: 12px;
  margin: 0;
}

.page-about .about-coverage__legend-item {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  margin: 0;
  font-size: 14.5px;
  line-height: 1.62;
  color: var(--c-muted);
}

.page-about .about-coverage__swatch {
  flex: none;
  width: 12px;
  height: 12px;
  margin-top: .38em;
  background: rgba(79, 195, 217, .4);
  border: 1px solid rgba(79, 195, 217, .68);
}

.page-about .about-coverage__swatch--focus {
  background: var(--c-signal);
  border-color: var(--c-signal);
}

.page-about .about-coverage__legend-item--focus {
  color: var(--c-white);
}

@media (min-width: 760px) {
  .page-about .about-dots {
    grid-template-columns: repeat(11, 12px);
  }
}

@media (min-width: 900px) {
  .page-about .about-coverage__grid {
    grid-template-columns: auto minmax(0, 1fr);
    gap: clamp(48px, 6vw, 96px);
  }
}

/* ---------- 版本演进 ---------- */
.page-about .about-versions {
  border-top: 1px solid rgba(42, 53, 96, .55);
}

.page-about .about-versions__grid {
  display: grid;
  gap: 14px;
  margin-top: clamp(28px, 3.5vw, 46px);
}

.page-about .about-versions__card {
  padding: 24px 22px 26px;
  border: 1px solid var(--c-line);
  background: rgba(22, 32, 74, .38);
}

.page-about .about-versions__card--new {
  background: rgba(22, 32, 74, .78);
  border-color: rgba(242, 193, 78, .34);
}

.page-about .about-versions__name {
  display: flex;
  align-items: center;
  gap: 12px;
  margin: 0 0 16px;
  font-size: 17px;
  font-weight: 700;
}

.page-about .about-versions__name .mono {
  display: inline-block;
  padding: 3px 9px;
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--c-space);
  background: var(--c-muted);
}

.page-about .about-versions__card--new .about-versions__name .mono {
  color: var(--c-space);
  background: var(--c-gold);
}

.page-about .about-versions__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 12px;
}

.page-about .about-versions__list li {
  position: relative;
  padding-left: 18px;
  font-size: 14.8px;
  line-height: 1.76;
  color: var(--c-muted);
}

.page-about .about-versions__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: .68em;
  width: 7px;
  height: 7px;
  background: var(--c-cyan);
  opacity: .75;
}

.page-about .about-versions__card--new .about-versions__list li {
  color: var(--c-white);
}

.page-about .about-versions__card--new .about-versions__list li::before {
  background: var(--c-gold);
  opacity: 1;
}

@media (min-width: 760px) {
  .page-about .about-versions__grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

/* ---------- 继续看 ---------- */
.page-about .about-next {
  border-top: 1px solid rgba(42, 53, 96, .55);
}

.page-about .about-next__grid {
  display: grid;
  gap: 14px;
  margin-top: clamp(28px, 3.5vw, 44px);
}

.page-about .about-next__card {
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: 24px 22px 26px;
  border: 1px solid var(--c-line);
  border-bottom: 2px solid var(--c-line);
  background: rgba(22, 32, 74, .42);
  color: inherit;
  text-decoration: none;
  clip-path: polygon(0 0, calc(100% - 18px) 0, 100% 18px, 100% 100%, 0 100%);
  transition: border-color .3s var(--ease), background-color .3s var(--ease);
}

.page-about .about-next__card:hover,
.page-about .about-next__card:focus-visible {
  border-color: rgba(242, 193, 78, .6);
  background: rgba(22, 32, 74, .82);
  outline: none;
}

.page-about .about-next__idx {
  font-size: 12.5px;
  letter-spacing: .14em;
  color: var(--c-cyan);
}

.page-about .about-next__card:hover .about-next__idx,
.page-about .about-next__card:focus-visible .about-next__idx {
  color: var(--c-gold);
}

.page-about .about-next__title {
  font-size: 18px;
  font-weight: 700;
  line-height: 1.4;
}

.page-about .about-next__desc {
  font-size: 14.8px;
  line-height: 1.76;
  color: var(--c-muted);
}

@media (min-width: 760px) {
  .page-about .about-next__grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 1024px) {
  .page-about .about-next__grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

/* ---------- 动效降级 ---------- */
@media (prefers-reduced-motion: reduce) {
  .page-about *,
  .page-about *::before,
  .page-about *::after {
    transition-duration: .2s !important;
    animation-duration: .2s !important;
  }
}
</main>