.page-about {
  --about-line: 1px solid var(--ink-700);
  --about-line-soft: 1px solid rgba(30, 58, 99, 0.7);
  --about-block-gap: clamp(28px, 5vw, 64px);
  overflow-wrap: break-word;
}

.page-about .section {
  padding-block: clamp(44px, 8vw, 96px);
}

/* ---------- 首屏 ---------- */
.page-about .about-cover {
  position: relative;
  padding-block: clamp(44px, 8vw, 104px) clamp(26px, 4vw, 52px);
}

.page-about .about-cover__title {
  max-width: 15ch;
  margin: 0.32em 0 0;
  color: var(--mist);
}

.page-about .about-cover__lead {
  max-width: 38em;
  margin: clamp(16px, 2.4vw, 26px) 0 0;
  color: var(--ink-400);
}

.page-about .about-cover__stats {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1px;
  margin: clamp(28px, 5vw, 54px) 0 0;
  padding: 0;
  background: var(--ink-700);
  border: var(--about-line);
}

.page-about .about-cover__stats > div {
  background: var(--ink-950);
  padding: clamp(14px, 2.2vw, 22px) clamp(12px, 1.8vw, 20px);
}

.page-about .about-cover__stats dt {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.18em;
  color: var(--ink-400);
}

.page-about .about-cover__stats dd {
  margin: 8px 0 0;
  font-size: clamp(19px, 3vw, 27px);
  line-height: 1.3;
  color: var(--lime);
}

/* ---------- 通用小节头 ---------- */
.page-about .about-head {
  max-width: 62ch;
  margin-bottom: var(--about-block-gap);
}

.page-about .about-head .u-56 {
  margin: 0.3em 0 0;
  color: var(--mist);
}

.page-about .about-head .lead {
  margin: clamp(14px, 2vw, 22px) 0 0;
  max-width: 38em;
  color: var(--ink-400);
}

.page-about .about-link {
  color: var(--lime);
  text-decoration: none;
  border-bottom: 1px solid rgba(183, 240, 74, 0.5);
  padding-bottom: 1px;
  transition: border-color var(--t) var(--ease);
}

.page-about .about-link:hover {
  border-bottom-color: var(--lime);
}

/* ---------- 边界两栏 ---------- */
.page-about .about-scope__cols {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  background: var(--ink-700);
  border: var(--about-line);
}

.page-about .about-scope__col {
  background: var(--ink-950);
  padding: clamp(20px, 3.2vw, 36px);
}

.page-about .about-scope__col--out {
  background: var(--ink-900);
}

.page-about .about-scope__col h3 {
  margin: 0 0 4px;
  color: var(--mist);
}

.page-about .about-scope__col--out h3 {
  color: var(--ink-400);
}

.page-about .about-list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .about-list li {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 14px;
  padding: 13px 0;
  border-top: var(--about-line-soft);
  font-size: 16px;
  line-height: 1.75;
  color: var(--mist);
}

.page-about .about-list__num {
  font-size: 13px;
  line-height: 1.95;
  color: var(--mono-lime);
}

.page-about .about-list--out li,
.page-about .about-list--out .about-list__num {
  color: var(--mute);
}

/* ---------- 编号刻度 ---------- */
.page-about .about-scale {
  list-style: none;
  margin: 0 0 clamp(26px, 4vw, 46px);
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--ink-700);
  border: var(--about-line);
}

.page-about .about-scale__item {
  background: var(--ink-950);
}

.page-about .about-scale__item a {
  display: flex;
  flex-direction: column;
  gap: 10px;
  height: 100%;
  padding: clamp(16px, 2.4vw, 24px) clamp(12px, 1.8vw, 18px) clamp(20px, 3vw, 30px);
  text-decoration: none;
  color: var(--mist);
  transition: background var(--t) var(--ease);
}

.page-about .about-scale__item a::after {
  content: "";
  display: block;
  width: 22px;
  height: 2px;
  margin-top: auto;
  background: var(--lime);
  opacity: 0.5;
  transition: width var(--t) var(--ease), opacity var(--t) var(--ease);
}

.page-about .about-scale__item a:hover {
  background: var(--ink-900);
}

.page-about .about-scale__item a:hover::after {
  width: 40px;
  opacity: 1;
}

.page-about .about-scale__num {
  font-size: clamp(21px, 3vw, 29px);
  letter-spacing: 0.04em;
  color: var(--mono-lime);
}

.page-about .about-scale__label {
  font-size: 14px;
  letter-spacing: 0.06em;
  color: var(--ink-400);
  transition: color var(--t) var(--ease);
}

.page-about .about-scale__item a:hover .about-scale__label {
  color: var(--lime);
}

/* ---------- 图形 ---------- */
.page-about .about-fig {
  margin: clamp(26px, 4.5vw, 52px) 0 0;
  border: var(--about-line);
  background: var(--ink-900);
}

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

.page-about .about-fig .media__cap {
  padding: 12px clamp(14px, 2vw, 18px);
  border-top: var(--about-line);
  font-size: 12px;
  letter-spacing: 0.1em;
  line-height: 1.7;
  color: var(--ink-400);
}

.page-about .about-fig--narrow {
  max-width: 640px;
}

.page-about .about-grid-note {
  display: grid;
  gap: 12px;
  margin-top: clamp(22px, 3vw, 36px);
  padding-left: clamp(14px, 2vw, 20px);
  border-left: 2px solid var(--lime);
  max-width: 62ch;
}

.page-about .about-grid-note p {
  margin: 0;
  font-size: 16px;
  line-height: 1.75;
  color: var(--ink-400);
}

.page-about .about-grid-note .about-link {
  font-size: 15px;
}

/* ---------- 更新周期（暖沙区块） ---------- */
.page-about .about-cycles {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: 1px solid var(--sand-edge);
}

.page-about .about-cycles__row {
  display: grid;
  gap: 10px;
  padding: clamp(20px, 3vw, 30px) 0;
  border-bottom: 1px solid var(--sand-edge);
}

.page-about .about-cycles__period {
  margin: 0;
  font-size: 13px;
  letter-spacing: 0.16em;
  color: var(--ink-on-sand);
}

.page-about .about-cycles__body h3 {
  margin: 0 0 8px;
  color: var(--ink-on-sand);
}

.page-about .about-cycles__body p {
  margin: 0;
  max-width: 40em;
  font-size: 16px;
  line-height: 1.75;
  color: var(--sand-soft);
}

.page-about .about-flow {
  margin-top: clamp(30px, 5vw, 56px);
  max-width: 800px;
}

.page-about .about-flow h3 {
  margin: 0 0 10px;
  color: var(--ink-on-sand);
}

.page-about .about-steps {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: 1px solid var(--sand-edge);
}

.page-about .about-steps li {
  display: grid;
  gap: 4px 16px;
  padding: 14px 0;
  border-bottom: 1px solid var(--sand-edge);
}

.page-about .about-steps__n {
  font-size: 14px;
  line-height: 1.8;
  color: var(--ink-on-sand);
}

.page-about .about-steps__t {
  font-weight: 700;
  color: var(--ink-on-sand);
}

.page-about .about-steps__d {
  font-size: 15px;
  line-height: 1.75;
  color: var(--sand-soft);
}

/* ---------- 分工 ---------- */
.page-about .about-team {
  display: grid;
  gap: 0;
}

.page-about .about-team__card {
  padding: 22px 0;
  border-top: var(--about-line);
}

.page-about .about-team__count {
  margin: 0;
  font-size: 13px;
  letter-spacing: 0.16em;
  color: var(--mono-lime);
}

.page-about .about-team__card h3 {
  margin: 8px 0 8px;
  color: var(--mist);
}

.page-about .about-team__card p:last-child {
  margin: 0;
  max-width: 34em;
  font-size: 15px;
  line-height: 1.75;
  color: var(--ink-400);
}

/* ---------- 发展脉络 ---------- */
.page-about .about-origin__inner {
  display: grid;
  gap: clamp(28px, 4vw, 48px);
}

.page-about .about-origin__text h2 {
  margin: 0.3em 0 clamp(22px, 3vw, 36px);
  color: var(--mist);
}

.page-about .about-timeline {
  list-style: none;
  margin: 0;
  padding: 0 0 0 26px;
  position: relative;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 4px;
  top: 6px;
  bottom: 16px;
  width: 1px;
  background: linear-gradient(180deg, var(--lime), var(--ink-700) 65%);
}

.page-about .about-timeline__node {
  position: relative;
  padding: 0 0 clamp(24px, 3.6vw, 38px);
}

.page-about .about-timeline__node::before {
  content: "";
  position: absolute;
  left: -26px;
  top: 8px;
  width: 9px;
  height: 9px;
  background: var(--ink-950);
  border: 1px solid var(--ink-400);
  transition: background var(--t) var(--ease), border-color var(--t) var(--ease);
}

.page-about .about-timeline__node:hover::before {
  background: var(--lime);
  border-color: var(--lime);
}

.page-about .about-timeline__stage {
  margin: 0;
  font-size: 12px;
  letter-spacing: 0.18em;
  color: var(--ink-400);
  transition: color var(--t) var(--ease);
}

.page-about .about-timeline__node:hover .about-timeline__stage {
  color: var(--lime);
}

.page-about .about-timeline__node h3 {
  margin: 6px 0 6px;
  color: var(--mist);
}

.page-about .about-timeline__body {
  margin: 0;
  max-width: 38em;
  font-size: 16px;
  line-height: 1.75;
  color: var(--ink-400);
}

.page-about .about-origin__fig {
  margin-top: 0;
}

/* ---------- 常见误解 ---------- */
.page-about .about-misread {
  display: grid;
  gap: clamp(26px, 4vw, 50px);
}

.page-about .about-misread__main h2 {
  margin: 0.3em 0 clamp(14px, 2vw, 20px);
  color: var(--mist);
}

.page-about .about-misread__main p {
  margin: 0 0 14px;
  max-width: 38em;
  font-size: 16px;
  line-height: 1.75;
  color: var(--ink-400);
}

.page-about .about-fold {
  border-top: var(--about-line);
}

.page-about .about-fold:last-child {
  border-bottom: var(--about-line);
}

.page-about .about-fold__sum {
  display: grid;
  grid-template-columns: 42px minmax(0, 1fr) 20px;
  gap: 12px;
  align-items: baseline;
  padding: 16px 0;
  cursor: pointer;
  list-style: none;
  color: var(--mist);
}

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

.page-about .about-fold__q {
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--mono-lime);
}

.page-about .about-fold__title {
  font-size: 17px;
  line-height: 1.6;
  transition: color var(--t) var(--ease);
}

.page-about .about-fold__sum:hover .about-fold__title {
  color: var(--lime);
}

.page-about .about-fold__sign::before {
  content: "+";
  display: block;
  font-family: var(--font-mono);
  font-size: 16px;
  line-height: 1;
  text-align: right;
  color: var(--lime);
}

.page-about .about-fold[open] .about-fold__sign::before {
  content: "\2212";
}

.page-about .about-fold__body {
  margin: 0;
  padding: 0 0 18px 54px;
  max-width: 40em;
  font-size: 15px;
  line-height: 1.8;
  color: var(--ink-400);
}

/* ---------- 交叉链接 ---------- */
.page-about .about-next h2 {
  margin: 0.4em 0 0;
  color: var(--mist);
}

.page-about .about-next__list {
  list-style: none;
  margin: clamp(18px, 3vw, 28px) 0 0;
  padding: 0;
  border-top: var(--about-line);
}

.page-about .about-next__list li {
  border-bottom: var(--about-line);
}

.page-about .about-next__list a {
  display: grid;
  grid-template-columns: 58px minmax(0, 1fr);
  gap: 16px;
  padding: 16px 0;
  text-decoration: none;
  color: var(--mist);
  font-size: 16px;
  line-height: 1.7;
  transition: color var(--t) var(--ease);
}

.page-about .about-next__list a:hover {
  color: var(--lime);
}

.page-about .about-next__list .mono {
  font-size: 13px;
  letter-spacing: 0.14em;
  color: var(--mono-lime);
}

/* ---------- 响应式 ---------- */
@media (min-width: 720px) {
  .page-about .about-scale {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .about-steps li {
    grid-template-columns: 56px 128px minmax(0, 1fr);
    align-items: baseline;
  }
}

@media (min-width: 880px) {
  .page-about .about-scope__cols {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-about .about-cycles__row {
    grid-template-columns: 170px minmax(0, 1fr);
    column-gap: clamp(24px, 4vw, 64px);
    align-items: start;
  }

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

  .page-about .about-team__card {
    border-top: var(--about-line);
    border-left: var(--about-line);
    padding: clamp(22px, 3vw, 30px);
  }

  .page-about .about-team__card:first-child {
    border-left: 0;
  }
}

@media (min-width: 920px) {
  .page-about .about-misread {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.05fr);
    align-items: start;
  }
}

@media (min-width: 1000px) {
  .page-about .about-origin__inner {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
    align-items: start;
  }

  .page-about .about-scale {
    grid-template-columns: repeat(6, minmax(0, 1fr));
  }
}

@media (max-width: 560px) {
  .page-about .about-cover__stats {
    grid-template-columns: 1fr;
  }

  .page-about .about-fold__sum {
    grid-template-columns: 34px minmax(0, 1fr) 18px;
    gap: 8px;
  }

  .page-about .about-fold__body {
    padding-left: 42px;
  }

  .page-about .about-next__list a {
    grid-template-columns: 48px minmax(0, 1fr);
    gap: 12px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-scale__item a,
  .page-about .about-scale__item a::after,
  .page-about .about-scale__label,
  .page-about .about-timeline__node::before,
  .page-about .about-timeline__stage,
  .page-about .about-fold__title,
  .page-about .about-next__list a,
  .page-about .about-link {
    transition: none;
  }
}