.page-about {
  --about-gutter: 20px;
  --about-rail: 148px;
  display: block;
  background: var(--ink);
  color: var(--text);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding: 56px 0 48px;
  overflow: hidden;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(180deg, rgba(53, 224, 208, .10) 0%, rgba(10, 16, 28, 0) 62%),
    linear-gradient(90deg, rgba(142, 134, 201, .07) 0%, rgba(10, 16, 28, 0) 55%);
  pointer-events: none;
}

.page-about .about-hero__inner {
  position: relative;
  z-index: 1;
}

.page-about .about-hero__crumbs {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--text-2);
  margin-bottom: 28px;
}

.page-about .about-hero__crumbs a {
  color: var(--text-2);
  text-decoration: none;
}

.page-about .about-hero__crumbs a:hover {
  color: var(--cyan);
}

.page-about .about-hero__kicker {
  color: var(--lilac);
  margin-bottom: 14px;
}

.page-about .about-hero__title {
  font-family: var(--font-cn);
  font-weight: 900;
  font-size: clamp(30px, 6.2vw, 62px);
  line-height: 1.14;
  letter-spacing: -.02em;
  margin: 0 0 22px;
  max-width: 20ch;
  background: linear-gradient(92deg, var(--text) 30%, var(--cyan) 118%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.page-about .about-hero__lead {
  color: var(--text-2);
  max-width: 62ch;
  margin-bottom: 36px;
}

.page-about .about-hero__facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  list-style: none;
  margin: 0;
  padding: 0;
  border: 1px solid var(--line);
  background: var(--line);
}

.page-about .about-hero__fact {
  background: var(--panel);
  padding: 16px 18px;
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.page-about .about-hero__fact-num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 30px;
  line-height: 1;
  color: var(--cyan);
}

.page-about .about-hero__fact:nth-child(2) .about-hero__fact-num {
  color: var(--league-1);
}

.page-about .about-hero__fact:nth-child(3) .about-hero__fact-num {
  color: var(--league-2);
}

.page-about .about-hero__fact:nth-child(4) .about-hero__fact-num {
  color: var(--amber);
}

.page-about .about-hero__fact-num .unit {
  font-size: .55em;
  margin-left: 2px;
  color: var(--text-2);
}

.page-about .about-hero__fact-label {
  color: var(--text-2);
}

.page-about .about-hero__rail {
  position: absolute;
  right: 0;
  top: 0;
  bottom: 0;
  width: 44px;
  display: none;
  flex-direction: column;
  justify-content: space-around;
  align-items: flex-end;
  padding: 32px 10px;
  border-left: 1px solid var(--line);
}

.page-about .about-hero__rail-tick {
  display: block;
  width: 12px;
  height: 1px;
  background: var(--line);
}

.page-about .about-hero__rail-tick:nth-child(2n) {
  width: 22px;
  background: var(--cyan-deep);
}

/* ---------- 起点 ---------- */
.page-about .about-origin__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 28px;
}

.page-about .about-origin__main .index-label {
  color: var(--lilac);
  display: block;
  margin-bottom: 12px;
}

.page-about .about-origin__title {
  margin: 0 0 20px;
  max-width: 24ch;
}

.page-about .about-origin__main p {
  color: var(--text-2);
  max-width: 68ch;
  margin: 0 0 16px;
}

.page-about .about-strong {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  color: var(--text);
  font-weight: 500;
}

.page-about .about-origin__note {
  border-left: 2px solid var(--amber);
}

.page-about .about-origin__note .index-label {
  color: var(--amber);
  display: block;
  margin-bottom: 14px;
}

.page-about .about-origin__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.page-about .about-origin__list li {
  display: grid;
  grid-template-columns: 30px 1fr;
  gap: 10px;
  color: var(--text-2);
  font-size: 14px;
  line-height: 1.7;
}

.page-about .about-origin__list-num {
  font-family: var(--font-mono);
  color: var(--lilac);
  font-size: 13px;
  padding-top: 2px;
}

/* ---------- 版本演进 ---------- */
.page-about .about-versions {
  position: relative;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  padding: 64px 0 56px;
  overflow: hidden;
}

.page-about .about-versions__backdrop {
  position: absolute;
  inset: 0;
  z-index: 0;
  opacity: .16;
  pointer-events: none;
}

.page-about .about-versions__backdrop-img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  max-width: 100%;
  filter: saturate(.85);
}

.page-about .about-versions__shell {
  position: relative;
  z-index: 1;
}

.page-about .about-versions__head {
  max-width: 66ch;
  margin-bottom: 44px;
}

.page-about .about-versions__head .index-label {
  color: var(--cyan);
  display: block;
  margin-bottom: 12px;
}

.page-about .about-versions__head .h2 {
  margin: 0 0 16px;
}

.page-about .about-versions__intro {
  color: var(--text-2);
  margin: 0;
}

.page-about .about-versions__body {
  display: grid;
  grid-template-columns: 1fr;
  gap: 24px;
}

.page-about .about-versions__stages {
  display: flex;
  gap: 8px;
  overflow-x: auto;
  padding-bottom: 6px;
  margin: 0 -4px 8px;
  scrollbar-width: thin;
}

.page-about .about-versions__stage {
  flex: 0 0 auto;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 14px;
  border: 1px solid var(--line);
  border-radius: var(--pill);
  background: rgba(16, 26, 43, .72);
  color: var(--text-2);
  text-decoration: none;
  font-size: 13px;
  white-space: nowrap;
  transition: border-color .24s var(--ease), color .24s var(--ease);
}

.page-about .about-versions__stage:hover,
.page-about .about-versions__stage:focus-visible {
  border-color: var(--cyan);
  color: var(--text);
}

.page-about .about-versions__stage-code {
  font-family: var(--font-mono);
  color: var(--cyan);
  font-size: 12px;
}

.page-about .about-versions__stage:nth-child(2) .about-versions__stage-code {
  color: var(--league-2);
}

.page-about .about-versions__stage:nth-child(3) .about-versions__stage-code {
  color: var(--amber);
}

.page-about .about-versions__stream {
  display: flex;
  flex-direction: column;
  gap: 26px;
}

.page-about .about-vcard {
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
  padding: 22px 0 0;
  border-top: 1px solid var(--line);
}

.page-about .about-vcard__marker {
  display: flex;
  align-items: center;
  gap: 12px;
}

.page-about .about-vcard__code {
  font-family: var(--font-mono);
  font-size: 20px;
  letter-spacing: .04em;
  color: var(--league-1);
  border: 1px solid var(--league-1);
  border-radius: var(--radius);
  padding: 4px 10px;
  line-height: 1;
}

.page-about .about-vcard--2 .about-vcard__code {
  color: var(--league-2);
  border-color: var(--league-2);
}

.page-about .about-vcard--3 .about-vcard__code {
  color: var(--amber);
  border-color: var(--amber);
}

.page-about .about-vcard__line {
  flex: 1;
  height: 1px;
  background: linear-gradient(90deg, var(--line), rgba(34, 48, 73, 0));
}

.page-about .about-vcard__phase {
  color: var(--lilac);
  margin: 0 0 8px;
}

.page-about .about-vcard__content .h3 {
  margin: 0 0 12px;
  color: var(--text);
}

.page-about .about-vcard__content p {
  color: var(--text-2);
  margin: 0 0 14px;
  max-width: 64ch;
}

.page-about .about-vcard__points {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .about-vcard__points li {
  background: rgba(16, 26, 43, .82);
  padding: 9px 14px;
  font-size: 14px;
  color: var(--text-2);
  position: relative;
  padding-left: 26px;
}

.page-about .about-vcard__points li::before {
  content: "";
  position: absolute;
  left: 12px;
  top: 50%;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  transform: translateY(-50%);
  background: var(--cyan-deep);
}

.page-about .about-vcard--2 .about-vcard__points li::before {
  background: var(--league-2);
}

.page-about .about-vcard--3 .about-vcard__points li::before {
  background: var(--amber-deep);
}

.page-about .about-versions__timeline {
  margin-top: 44px;
  border-top: 1px solid var(--line);
  padding-top: 26px;
}

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

/* ---------- 团队 ---------- */
.page-about .about-team__head {
  max-width: 64ch;
  margin-bottom: 36px;
}

.page-about .about-team__head .index-label {
  color: var(--lilac);
  display: block;
  margin-bottom: 12px;
}

.page-about .about-team__head .h2 {
  margin: 0 0 16px;
}

.page-about .about-team__intro {
  color: var(--text-2);
  margin: 0;
}

.page-about .about-team__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 26px;
}

.page-about .about-team__figure {
  margin: 0;
  border: 1px solid var(--line);
  background: var(--panel);
}

.page-about .about-team__img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
}

.page-about .about-team__figure .media__cap {
  display: block;
  padding: 12px 16px;
  font-size: 13px;
  color: var(--text-2);
  border-top: 1px solid var(--line);
}

.page-about .about-team__roster {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .about-team__member {
  background: var(--panel);
  display: grid;
  grid-template-columns: 62px 1fr;
  gap: 16px;
  padding: 20px 18px;
  align-items: start;
}

.page-about .about-team__member:nth-child(2) {
  background: rgba(36, 31, 58, .62);
}

.page-about .about-team__member-num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 32px;
  line-height: 1;
  color: var(--cyan);
}

.page-about .about-team__member:nth-child(2) .about-team__member-num {
  color: var(--amber);
}

.page-about .about-team__member:nth-child(3) .about-team__member-num {
  color: var(--lilac);
}

.page-about .about-team__member-title {
  margin: 0 0 8px;
  color: var(--text);
}

.page-about .about-team__member-body p {
  margin: 0;
  color: var(--text-2);
  font-size: 14px;
  max-width: 60ch;
}

/* ---------- 数据来源 ---------- */
.page-about .about-data {
  border-top: 1px solid var(--line);
}

.page-about .about-data__layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: 28px;
  margin-bottom: 44px;
}

.page-about .about-data__intro .index-label {
  color: var(--cyan);
  display: block;
  margin-bottom: 12px;
}

.page-about .about-data__intro .h2 {
  margin: 0 0 18px;
  max-width: 22ch;
}

.page-about .about-data__intro p {
  color: var(--text-2);
  margin: 0 0 16px;
  max-width: 60ch;
}

.page-about .about-data__link {
  margin-top: 6px;
}

.page-about .about-data__figure {
  margin: 0;
  border: 1px solid var(--line);
  background: var(--plum);
  position: relative;
}

.page-about .about-data__figure::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(53, 224, 208, .06) 1px, transparent 1px),
    linear-gradient(90deg, rgba(53, 224, 208, .06) 1px, transparent 1px);
  background-size: 36px 36px;
  pointer-events: none;
}

.page-about .about-data__img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  position: relative;
  z-index: 1;
  mix-blend-mode: screen;
}

.page-about .about-data__figure .media__cap {
  display: block;
  padding: 12px 16px;
  font-size: 13px;
  color: var(--text-2);
  border-top: 1px solid var(--line);
  position: relative;
  z-index: 2;
  background: var(--plum);
}

.page-about .about-data__chain {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .about-data__step {
  background: var(--panel);
  padding: 22px 20px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.page-about .about-data__step-code {
  color: var(--lilac);
}

.page-about .about-data__step .h3 {
  margin: 0;
  color: var(--text);
  font-size: 18px;
}

.page-about .about-data__step p {
  margin: 0;
  color: var(--text-2);
  font-size: 14px;
}

/* ---------- 规模 ---------- */
.page-about .about-scale__head {
  max-width: 56ch;
  margin-bottom: 32px;
}

.page-about .about-scale__head .index-label {
  color: var(--amber);
  display: block;
  margin-bottom: 12px;
}

.page-about .about-scale__head .h2 {
  margin: 0;
}

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

.page-about .about-scale__cell {
  background: var(--panel);
  padding: 24px 20px;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.page-about .about-scale__cell--lead {
  background: linear-gradient(150deg, rgba(53, 224, 208, .16), rgba(16, 26, 43, .9) 62%);
}

.page-about .about-scale__value {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(30px, 5vw, 40px);
  line-height: 1;
  color: var(--cyan);
}

.page-about .about-scale__value .unit {
  font-size: .5em;
  margin-left: 2px;
  color: var(--text-2);
}

.page-about .about-scale__cell:nth-child(2) .about-scale__value {
  color: var(--amber);
}

.page-about .about-scale__cell:nth-child(3) .about-scale__value {
  color: var(--league-1);
}

.page-about .about-scale__cell:nth-child(4) .about-scale__value {
  color: var(--league-2);
}

.page-about .about-scale__label {
  color: var(--lilac);
}

.page-about .about-scale__desc {
  margin: 0;
  color: var(--text-2);
  font-size: 14px;
  line-height: 1.7;
}

.page-about .about-scale__foot {
  margin: 22px 0 0;
  color: var(--text-2);
}

.page-about .about-scale__foot a,
.page-about .about-cadence__foot a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(53, 224, 208, .35);
}

.page-about .about-scale__foot a:hover,
.page-about .about-cadence__foot a:hover {
  border-bottom-color: var(--cyan);
}

/* ---------- 更新节奏 ---------- */
.page-about .about-cadence {
  border-top: 1px solid var(--line);
}

.page-about .about-cadence__head {
  max-width: 64ch;
  margin-bottom: 32px;
}

.page-about .about-cadence__head .index-label {
  color: var(--cyan);
  display: block;
  margin-bottom: 12px;
}

.page-about .about-cadence__head .h2 {
  margin: 0 0 16px;
}

.page-about .about-cadence__intro {
  color: var(--text-2);
  margin: 0;
}

.page-about .about-cadence__rows {
  display: flex;
  flex-direction: column;
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .about-cadence__row {
  background: var(--panel);
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
  padding: 22px 18px 22px 24px;
  position: relative;
}

.page-about .about-cadence__row:nth-child(2) {
  background: rgba(36, 31, 58, .5);
}

.page-about .about-cadence__tick {
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 3px;
  background: var(--cyan-deep);
}

.page-about .about-cadence__row:nth-child(2) .about-cadence__tick {
  background: var(--amber-deep);
}

.page-about .about-cadence__row:nth-child(3) .about-cadence__tick {
  background: var(--lilac);
}

.page-about .about-cadence__row-meta {
  display: flex;
  align-items: baseline;
  gap: 12px;
  flex-wrap: wrap;
}

.page-about .about-cadence__freq {
  color: var(--text);
}

.page-about .about-cadence__freq-num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 13px;
  color: var(--text-2);
}

.page-about .about-cadence__row-body .h3 {
  margin: 0 0 8px;
  color: var(--text);
  font-size: 19px;
}

.page-about .about-cadence__row-body p {
  margin: 0;
  color: var(--text-2);
  font-size: 14px;
  max-width: 62ch;
}

.page-about .about-cadence__foot {
  margin: 22px 0 0;
  color: var(--text-2);
}

/* ---------- 末尾 CTA ---------- */
.page-about .about-cta {
  padding-bottom: 72px;
}

.page-about .about-cta__panel {
  border: 1px solid var(--line);
  background:
    linear-gradient(120deg, rgba(53, 224, 208, .12), rgba(10, 16, 28, 0) 60%),
    var(--panel);
  padding: 30px 22px;
  display: flex;
  flex-direction: column;
  gap: 24px;
}

.page-about .about-cta__copy .index-label {
  color: var(--lilac);
  display: block;
  margin-bottom: 12px;
}

.page-about .about-cta__title {
  margin: 0 0 14px;
  max-width: 24ch;
}

.page-about .about-cta__copy p {
  margin: 0;
  color: var(--text-2);
  max-width: 62ch;
}

.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

/* ---------- 响应式 ---------- */
@media (min-width: 720px) {
  .page-about .about-hero__facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .about-origin__grid {
    grid-template-columns: minmax(0, 1.55fr) minmax(0, 1fr);
    gap: 36px;
  }

  .page-about .about-team__grid {
    grid-template-columns: minmax(0, 1.1fr) minmax(0, 1fr);
    align-items: start;
  }

  .page-about .about-data__layout {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.05fr);
    align-items: start;
    gap: 36px;
  }

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

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

  .page-about .about-scale__cell--lead {
    grid-column: span 2;
  }

  .page-about .about-cadence__row {
    grid-template-columns: minmax(0, 180px) minmax(0, 1fr);
    align-items: start;
    gap: 20px;
  }

  .page-about .about-cta__panel {
    flex-direction: row;
    align-items: center;
    justify-content: space-between;
    padding: 38px 32px;
    gap: 32px;
  }
}

@media (min-width: 1024px) {
  .page-about .about-hero {
    padding: 76px 0 60px;
  }

  .page-about .about-hero__title {
    font-size: clamp(44px, 4.6vw, 68px);
  }

  .page-about .about-hero__rail {
    display: flex;
  }

  .page-about .about-versions {
    padding: 84px 0 72px;
  }

  .page-about .about-versions__body {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    gap: 40px;
    align-items: start;
  }

  .page-about .about-versions__stages {
    position: sticky;
    top: 108px;
    flex-direction: column;
    overflow: visible;
    margin: 0;
    padding: 0;
    gap: 10px;
  }

  .page-about .about-versions__stage {
    border-radius: var(--radius);
    justify-content: flex-start;
    white-space: normal;
    padding: 12px 14px;
    border-left: 2px solid var(--line);
    border-top-color: transparent;
    border-right-color: transparent;
    border-bottom-color: transparent;
    background: transparent;
  }

  .page-about .about-versions__stage:hover,
  .page-about .about-versions__stage:focus-visible {
    border-left-color: var(--cyan);
    background: rgba(16, 26, 43, .72);
  }

  .page-about .about-vcard {
    grid-template-columns: 84px minmax(0, 1fr);
    gap: 22px;
    padding-top: 26px;
  }

  .page-about .about-vcard__marker {
    flex-direction: column;
    align-items: flex-start;
    gap: 14px;
  }

  .page-about .about-vcard__line {
    width: 1px;
    flex: 1;
    height: auto;
    min-height: 40px;
    background: linear-gradient(180deg, var(--line), rgba(34, 48, 73, 0));
  }

  .page-about .about-data__chain {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .about-scale__board {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .about-scale__cell--lead {
    grid-column: span 1;
  }

  .page-about .about-team__member {
    grid-template-columns: 78px 1fr;
  }
}

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