.page-about {
  --about-gap: clamp(20px, 3.2vw, 44px);
  --about-sec-pad: clamp(38px, 6vw, 88px);
  color: var(--text);
}

.page-about .about-link {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(0, 229, 160, 0.4);
  padding-bottom: 1px;
}
.page-about .about-link:hover,
.page-about .about-link:focus-visible {
  border-bottom-color: var(--cyan);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding: clamp(26px, 4.6vw, 62px) 0 clamp(20px, 3vw, 36px);
  overflow: hidden;
}
.page-about .about-hero::before {
  content: "";
  position: absolute;
  top: -40%;
  right: -18%;
  width: 58%;
  height: 180%;
  background: linear-gradient(135deg, rgba(0, 229, 160, 0.09), rgba(0, 229, 160, 0) 62%);
  transform: rotate(14deg);
  pointer-events: none;
}
.page-about .about-hero__grid {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(22px, 3vw, 34px);
}
.page-about .about-hero__lead .index-label {
  color: var(--cold);
}
.page-about .about-hero__lead h1 {
  margin: 12px 0 0;
  font-family: var(--font-display);
  font-size: clamp(28px, 6.4vw, 58px);
  line-height: 1.06;
  letter-spacing: -0.01em;
  text-transform: uppercase;
  color: var(--text);
  max-width: 22ch;
}
.page-about .about-hero__intro {
  margin: clamp(14px, 2vw, 22px) 0 0;
  max-width: 58ch;
  font-size: clamp(14.5px, 1.35vw, 16.5px);
  line-height: 1.78;
  color: var(--text);
}
.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: clamp(18px, 2.4vw, 28px);
}

.page-about .about-hero__facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 0;
  background: var(--line-soft);
  border: 1px solid var(--line-soft);
}
.page-about .about-fact {
  background: var(--green-deep);
  padding: 14px 14px 16px;
}
.page-about .about-fact dt {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--cold);
}
.page-about .about-fact dd {
  margin: 8px 0 0;
  display: flex;
  align-items: baseline;
  gap: 4px;
  color: var(--cyan);
}
.page-about .about-fact dd .num {
  font-family: var(--font-mono);
  font-size: clamp(28px, 4.4vw, 40px);
  line-height: 1;
  font-variant-numeric: tabular-nums;
}
.page-about .about-fact dd small {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--cold);
}

.page-about .about-hero__figure {
  margin: 0;
  padding: 0 var(--pad) clamp(24px, 4vw, 46px);
  max-width: 1600px;
  margin-inline: auto;
}
.page-about .about-hero__figure .media-frame__inner {
  aspect-ratio: 16 / 9;
}
.page-about .about-hero__figure img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

/* ---------- 章节索引 ---------- */
.page-about .about-index {
  position: sticky;
  top: var(--cmd-h);
  z-index: 6;
  background: var(--green-night);
  border-top: 1px solid var(--line-soft);
  border-bottom: 1px solid var(--line-soft);
}
.page-about .about-index__inner {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding-top: 10px;
  padding-bottom: 10px;
}
.page-about .about-index__inner > .index-label {
  color: var(--cold);
}
.page-about .about-index__list {
  display: flex;
  gap: clamp(14px, 2vw, 30px);
  margin: 0;
  padding: 0 0 4px;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: thin;
}
.page-about .about-index__link {
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
  white-space: nowrap;
  padding: 6px 0;
  font-size: 13px;
  color: var(--text);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color 0.24s var(--ease), border-color 0.24s var(--ease);
}
.page-about .about-index__link .num {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--cold);
}
.page-about .about-index__link:hover,
.page-about .about-index__link:focus-visible {
  color: var(--cyan);
  border-bottom-color: var(--cyan);
}
.page-about .about-index__link:hover .num,
.page-about .about-index__link:focus-visible .num {
  color: var(--cyan);
}

/* ---------- 通用章节 ---------- */
.page-about .about-sec {
  padding: var(--about-sec-pad) 0;
  border-bottom: 1px solid var(--line-soft);
}
.page-about .about-sec .section__bar {
  border-bottom: 1px solid var(--line-soft);
  padding-bottom: 12px;
}
.page-about .about-sec .section__index {
  color: var(--cyan);
}
.page-about .about-lead {
  margin: clamp(18px, 2.4vw, 26px) 0 0;
  max-width: 62ch;
  font-size: 15px;
  line-height: 1.8;
}

.page-about .about-cols {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--about-gap);
  margin-top: clamp(20px, 3vw, 34px);
}
.page-about .about-cols__main p {
  margin: 0 0 1.2em;
  max-width: 60ch;
  font-size: clamp(14.5px, 1.2vw, 16px);
  line-height: 1.82;
  color: var(--text);
}
.page-about .about-cols__main p:last-child {
  margin-bottom: 0;
}

.page-about .about-list {
  margin: 0;
  padding: 0;
  list-style: none;
}
.page-about .about-list li {
  position: relative;
  padding: 11px 0 11px 20px;
  font-size: 14px;
  line-height: 1.7;
  color: var(--text);
  border-top: 1px solid var(--line-soft);
}
.page-about .about-list li:first-child {
  border-top: 0;
  padding-top: 0;
}
.page-about .about-list li::before {
  content: "";
  position: absolute;
  left: 2px;
  top: 19px;
  width: 7px;
  height: 1px;
  background: var(--orange);
}
.page-about .about-list li:first-child::before {
  top: 12px;
}

/* ---------- 覆盖范围 ---------- */
.page-about .about-scope__figure {
  margin: clamp(20px, 3vw, 32px) 0 0;
}
.page-about .about-scope__figure .media-frame__inner {
  aspect-ratio: 3 / 2;
}
.page-about .about-scope__figure img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.page-about .scope-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin-top: clamp(20px, 3vw, 34px);
  background: var(--line-soft);
  border: 1px solid var(--line-soft);
}
.page-about .scope-cell {
  background: var(--green-deep);
  padding: clamp(14px, 1.8vw, 20px) clamp(13px, 1.6vw, 20px) clamp(16px, 2vw, 22px);
  transition: background 0.24s var(--ease), transform 0.24s var(--ease);
}
.page-about .scope-cell:hover {
  background: var(--green-mid);
  transform: translateY(-2px);
}
.page-about .scope-cell .index-label {
  color: var(--cold);
}
.page-about .scope-cell__num {
  margin: 10px 0 0;
  font-family: var(--font-mono);
  font-size: clamp(34px, 6vw, 54px);
  line-height: 0.94;
  font-variant-numeric: tabular-nums;
  color: var(--cyan);
  letter-spacing: -0.02em;
}
.page-about .scope-cell__meta {
  margin: 10px 0 0;
  font-size: 12.5px;
  line-height: 1.6;
  color: var(--cold);
}

.page-about .about-note {
  margin: clamp(18px, 2.4vw, 26px) 0 0;
  max-width: 66ch;
  padding-left: 14px;
  border-left: 1px solid var(--orange);
  font-size: 13.5px;
  line-height: 1.8;
  color: var(--cold);
}

/* ---------- 四步流程 ---------- */
.page-about .pipeline {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--about-gap);
  margin-top: clamp(22px, 3vw, 38px);
}
.page-about .pipeline__list {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 0;
  margin: 0;
  padding: 0;
  list-style: none;
  counter-reset: pipe;
}
.page-about .pipeline__step {
  position: relative;
  padding: clamp(16px, 2vw, 24px) 0 clamp(16px, 2vw, 24px) clamp(46px, 6vw, 68px);
  border-top: 1px solid var(--line-soft);
}
.page-about .pipeline__list .pipeline__step:first-child {
  border-top: 0;
}
.page-about .pipeline__step::before {
  content: "";
  position: absolute;
  left: clamp(16px, 2.2vw, 24px);
  top: clamp(20px, 2.4vw, 30px);
  bottom: -1px;
  width: 1px;
  background: var(--line-soft);
}
.page-about .pipeline__list .pipeline__step:last-child::before {
  bottom: 40%;
}
.page-about .pipeline__no {
  position: absolute;
  left: 0;
  top: clamp(16px, 2vw, 22px);
  width: clamp(26px, 3.6vw, 36px);
  height: clamp(26px, 3.6vw, 36px);
  display: grid;
  place-items: center;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--green-night);
  background: var(--cyan);
}
.page-about .pipeline__title {
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(17px, 1.6vw, 21px);
  letter-spacing: 0.01em;
  color: var(--text);
}
.page-about .pipeline__text {
  margin: 8px 0 0;
  max-width: 52ch;
  font-size: 14px;
  line-height: 1.78;
  color: var(--text);
}
.page-about .pipeline__time {
  display: inline-block;
  margin-top: 12px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.08em;
  color: var(--orange);
  border-top: 1px solid rgba(255, 107, 53, 0.45);
  padding-top: 6px;
}
.page-about .pipeline__media {
  margin: 0;
}
.page-about .pipeline__media img {
  width: 100%;
  height: auto;
  display: block;
  object-fit: cover;
}

/* ---------- 版本时间线 ---------- */
.page-about .tl {
  margin: clamp(22px, 3vw, 38px) 0 0;
  padding: 0;
  list-style: none;
}
.page-about .tl__item {
  position: relative;
  padding-left: clamp(20px, 2.4vw, 30px);
  border-left: 1px solid var(--line);
}
.page-about .tl__item:first-child {
  border-left-color: var(--line-soft);
}
.page-about .tl__item::before {
  content: "";
  position: absolute;
  left: -4px;
  top: clamp(20px, 2.6vw, 28px);
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--green-deep);
  border: 1px solid var(--line);
}
.page-about .tl__item--current::before {
  background: var(--cyan);
  border-color: var(--cyan);
  box-shadow: 0 0 0 4px rgba(0, 229, 160, 0.14);
}
.page-about .tl__node {
  border-bottom: 1px solid var(--line-soft);
}
.page-about .tl__summary {
  display: flex;
  align-items: baseline;
  flex-wrap: wrap;
  gap: 6px 14px;
  padding: clamp(14px, 2vw, 20px) 0;
  cursor: pointer;
  list-style: none;
}
.page-about .tl__summary::-webkit-details-marker {
  display: none;
}
.page-about .tl__ver {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.06em;
  color: var(--cyan);
}
.page-about .tl__range {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--cold);
}
.page-about .tl__name {
  font-size: clamp(14.5px, 1.3vw, 16.5px);
  line-height: 1.5;
  color: var(--text);
}
.page-about .tl__chev {
  margin-left: auto;
  width: 9px;
  height: 9px;
  border-right: 1px solid var(--cyan);
  border-bottom: 1px solid var(--cyan);
  transform: rotate(45deg);
  transition: transform 0.28s var(--ease);
  flex: 0 0 auto;
  align-self: center;
}
.page-about .tl__node[open] .tl__chev {
  transform: rotate(-135deg);
}
.page-about .tl__body {
  padding: 0 0 clamp(16px, 2vw, 24px);
}
.page-about .tl__body p {
  margin: 0;
  max-width: 62ch;
  font-size: 14px;
  line-height: 1.82;
  color: var(--text);
}

/* ---------- 团队分工 ---------- */
.page-about .crew-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  margin-top: clamp(20px, 3vw, 32px);
  background: var(--line-soft);
  border: 1px solid var(--line-soft);
}
.page-about .crew-card {
  background: var(--green-deep);
  padding: clamp(16px, 2vw, 22px);
  transition: background 0.24s var(--ease), transform 0.24s var(--ease);
}
.page-about .crew-card:hover {
  background: var(--green-mid);
  transform: translateY(-2px);
}
.page-about .crew-card .index-label {
  color: var(--cold);
}
.page-about .crew-card__title {
  margin: 10px 0 0;
  font-family: var(--font-display);
  font-size: clamp(16px, 1.5vw, 19px);
  letter-spacing: 0.01em;
  color: var(--text);
}
.page-about .crew-card__text {
  margin: 8px 0 14px;
  font-size: 13.5px;
  line-height: 1.78;
  color: var(--text);
}

/* ---------- 纠错区（纸面） ---------- */
.page-about .section--paper {
  color: var(--ink);
  border-bottom: 0;
}
.page-about .section--paper .section__bar {
  border-bottom-color: var(--paper-line);
}
.page-about .section--paper .section__index {
  color: var(--orange-ink);
}
.page-about .section--paper .section__title {
  color: var(--ink);
}
.page-about .paper-box {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(22px, 3vw, 40px);
  margin-top: clamp(20px, 3vw, 32px);
}
.page-about .paper-box__main p {
  margin: 0 0 1.1em;
  max-width: 60ch;
  font-size: 14.5px;
  line-height: 1.82;
  color: var(--ink);
}
.page-about .paper-box__main p:last-child {
  margin-bottom: 0;
}
.page-about .paper-steps {
  margin: 0;
  padding: 0;
  list-style: none;
  counter-reset: none;
}
.page-about .paper-steps li {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding: 10px 0;
  border-top: 1px solid var(--paper-line);
  font-size: 13.5px;
  line-height: 1.6;
  color: var(--ink);
}
.page-about .paper-steps li:first-child {
  border-top: 0;
}
.page-about .paper-steps .num {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--orange-ink);
}
.page-about .paper-box__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: clamp(18px, 2.4vw, 26px);
}

/* ---------- 响应式 ---------- */
@media (min-width: 700px) {
  .page-about .scope-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
  .page-about .crew-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .page-about .paper-box {
    grid-template-columns: minmax(0, 1.25fr) minmax(0, 1fr);
  }
}

@media (min-width: 980px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.5fr) minmax(280px, 1fr);
    gap: 0;
    align-items: end;
  }
  .page-about .about-hero__facts {
    align-self: end;
    margin-left: clamp(24px, 3vw, 52px);
  }
  .page-about .about-cols {
    grid-template-columns: minmax(0, 62fr) minmax(0, 34fr);
  }
  .page-about .pipeline {
    grid-template-columns: minmax(0, 1.55fr) minmax(0, 1fr);
    align-items: start;
  }
  .page-about .pipeline__media {
    position: sticky;
    top: calc(var(--cmd-h) + 92px);
  }
}

@media (min-width: 1120px) {
  .page-about .crew-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
  .page-about .about-hero__lead h1 {
    max-width: 20ch;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .scope-cell,
  .page-about .crew-card,
  .page-about .tl__chev,
  .page-about .about-index__link {
    transition: none;
  }
  .page-about .scope-cell:hover,
  .page-about .crew-card:hover {
    transform: none;
  }
}