.page-about {
  --about-dim: #4B545E;
  --about-line: rgba(14, 16, 19, 0.12);
  background: var(--paper);
  color: var(--ink);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  isolation: isolate;
  overflow: hidden;
  padding: 26px 0 52px;
  background:
    radial-gradient(120% 90% at 88% 0%, rgba(17, 197, 201, 0.16), transparent 62%),
    var(--ink);
  color: var(--paper);
}

.page-about .about-hero::after {
  content: "悟";
  position: absolute;
  z-index: -1;
  right: -5vw;
  top: -8vw;
  font-size: clamp(200px, 46vw, 460px);
  font-weight: 900;
  line-height: 0.8;
  color: rgba(242, 106, 27, 0.09);
  transform: rotate(-6deg);
  pointer-events: none;
}

.page-about .about-hero__inner {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 16px;
}

.page-about .about-hero__crumbs {
  margin-bottom: 4px;
}

.page-about .about-hero__eyebrow {
  margin: 0;
  color: var(--gold);
}

.page-about .about-hero__title {
  margin: 0;
  font-size: clamp(38px, 8.6vw, 80px);
  font-weight: 900;
  line-height: 1.04;
  letter-spacing: -0.02em;
}

.page-about .about-hero__lede {
  margin: 4px 0 0;
  max-width: 34em;
  color: var(--body-dim);
  font-size: 16px;
  line-height: 1.85;
}

.page-about .about-hero__facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px;
  margin: 12px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-fact {
  padding: 12px 14px;
  border: 1px solid var(--line-dark);
  border-left: 3px solid var(--gold);
  background: rgba(25, 29, 34, 0.72);
}

.page-about .about-fact__num {
  display: block;
  font-family: var(--font-mono);
  font-size: 26px;
  font-weight: 700;
  line-height: 1.2;
  color: var(--gold);
}

.page-about .about-fact__label {
  display: block;
  margin-top: 4px;
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--muted);
}

/* ---------- 正文两栏 ---------- */
.page-about .about-body {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 28px;
  padding-block: 40px 56px;
}

.page-about .about-index {
  padding: 2px 0 2px 16px;
  border-left: 2px solid var(--gold);
}

.page-about .about-index__kicker {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--grey);
}

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

.page-about .about-index__link {
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
  padding-bottom: 2px;
  border-bottom: 1px solid transparent;
  color: var(--ink);
  font-size: 14px;
  font-weight: 600;
  text-decoration: none;
  transition: color var(--t-fast) var(--ease), border-color var(--t-fast) var(--ease);
}

.page-about .about-index__link:hover,
.page-about .about-index__link:focus-visible {
  color: var(--gold-deep);
  border-bottom-color: currentColor;
}

.page-about .about-index__no {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  color: var(--grey);
}

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

.page-about .about-index__note a {
  color: var(--gold-deep);
  font-weight: 600;
}

.page-about .about-content {
  min-width: 0;
}

/* ---------- 章节 ---------- */
.page-about .about-section {
  position: relative;
  padding-block: 30px 40px;
  border-top: 1px solid var(--about-line);
  scroll-margin-top: 96px;
}

.page-about .about-section:first-child {
  padding-top: 0;
  border-top: 0;
}

.page-about .about-section__head {
  display: flex;
  align-items: baseline;
  gap: 12px;
  margin-bottom: 18px;
}

.page-about .about-section__no {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.12em;
  color: var(--gold);
}

.page-about .about-section__title {
  margin: 0;
  font-size: clamp(23px, 4.4vw, 33px);
  font-weight: 900;
  line-height: 1.22;
  letter-spacing: -0.01em;
}

.page-about .about-text {
  margin: 0 0 16px;
  max-width: 38em;
  font-size: 16px;
  line-height: 1.85;
}

.page-about .about-text--after {
  margin-top: 20px;
}

.page-about .about-text a {
  color: var(--gold-deep);
  font-weight: 600;
  text-decoration: underline;
  text-underline-offset: 3px;
}

.page-about .about-quote {
  margin: 22px 0 22px;
  padding: 14px 0 14px 16px;
  border-left: 3px solid var(--speed-deep);
  font-size: 17px;
  font-weight: 800;
  line-height: 1.65;
  color: var(--teal-900);
}

/* ---------- 图文错位 ---------- */
.page-about .about-two-col {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 22px;
}

.page-about .about-figure {
  margin: 20px 0 22px;
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  border: 1px solid var(--about-line);
  border-radius: var(--radius-sm);
}

.page-about .about-figure__cap {
  margin-top: 10px;
  font-size: 12.5px;
  line-height: 1.7;
  color: var(--grey);
}

.page-about .about-figure--side {
  margin-top: 0;
}

/* ---------- 三个小组 ---------- */
.page-about .about-flow {
  display: grid;
  gap: 12px;
  margin: 20px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-flow__step {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 12px;
  padding: 14px 16px;
  border: 1px solid var(--about-line);
  background: var(--paper-2);
}

.page-about .about-flow__no {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  color: var(--gold-deep);
  padding-top: 3px;
}

.page-about .about-flow__title {
  margin: 0 0 4px;
  font-size: 15px;
  font-weight: 800;
}

.page-about .about-flow__desc {
  margin: 0;
  font-size: 14px;
  line-height: 1.78;
  color: var(--about-dim);
}

/* ---------- 覆盖规模 ---------- */
.page-about .about-scale {
  margin-top: 20px;
  padding: 8px 18px 14px;
  background: var(--teal-900);
  border-radius: var(--radius);
  color: var(--paper);
}

.page-about .about-scale__row {
  padding-block: 14px;
  border-top: 1px solid var(--line-dark-soft);
}

.page-about .about-scale__row:first-child {
  border-top: 0;
}

.page-about .about-scale__meta {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: 8px 14px;
}

.page-about .about-scale__label {
  font-size: 13.5px;
  color: var(--paper);
}

.page-about .about-scale__value {
  font-family: var(--font-mono);
  font-size: 16px;
  font-weight: 700;
  color: var(--speed);
}

.page-about .about-scale__track {
  height: 6px;
  margin-top: 9px;
  background: rgba(246, 241, 231, 0.12);
  border-radius: 99px;
  overflow: hidden;
}

.page-about .about-scale__fill {
  display: block;
  height: 100%;
  width: var(--w, 100%);
  border-radius: 99px;
  background: linear-gradient(90deg, var(--gold), var(--speed));
}

/* ---------- 时间轴 ---------- */
.page-about .about-timeline {
  position: relative;
  margin: 20px 0 0;
  padding: 0 0 0 24px;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 10px;
  bottom: 12px;
  width: 2px;
  background: linear-gradient(180deg, var(--gold), rgba(242, 106, 27, 0.12));
}

.page-about .about-timeline__item {
  position: relative;
  border-bottom: 1px solid var(--about-line);
}

.page-about .about-timeline__item:last-child {
  border-bottom: 0;
}

.page-about .about-timeline__item::before {
  content: "";
  position: absolute;
  left: -25px;
  top: 16px;
  width: 11px;
  height: 11px;
  border: 2px solid var(--gold);
  border-radius: 50%;
  background: var(--paper);
}

.page-about .about-timeline__summary {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 10px;
  padding: 14px 0;
  cursor: pointer;
  list-style: none;
  font-size: 16px;
  font-weight: 800;
  color: var(--ink);
  transition: color var(--t-fast) var(--ease);
}

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

.page-about .about-timeline__summary:hover,
.page-about .about-timeline__summary:focus-visible {
  color: var(--gold-deep);
}

.page-about .about-timeline__item[open] > .about-timeline__summary {
  color: var(--gold-deep);
}

.page-about .about-timeline__phase {
  padding: 2px 9px;
  border: 1px solid currentColor;
  border-radius: 99px;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.1em;
  color: var(--gold-deep);
}

.page-about .about-timeline__body {
  padding: 0 0 16px;
  max-width: 36em;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--about-dim);
}

/* ---------- 合作 ---------- */
.page-about .about-partners {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
  margin-top: 20px;
}

.page-about .about-partner {
  padding: 16px 16px 18px;
  border: 1px solid var(--about-line);
  border-top: 3px solid var(--gold);
  background: var(--paper-2);
}

.page-about .about-partner__num {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 30px;
  font-weight: 700;
  line-height: 1.1;
  color: var(--gold-deep);
}

.page-about .about-partner__title {
  margin: 6px 0 8px;
  font-size: 15px;
  font-weight: 800;
  line-height: 1.4;
}

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

/* ---------- 尾部行动条 ---------- */
.page-about .about-cta {
  padding-bottom: 64px;
}

.page-about .about-cta__box {
  position: relative;
  isolation: isolate;
  overflow: hidden;
  display: grid;
  gap: 14px;
  padding: 26px 20px;
  background: var(--ink);
  border-radius: var(--radius);
  color: var(--paper);
}

.page-about .about-cta__box::after {
  content: "悟";
  position: absolute;
  z-index: -1;
  right: -10px;
  bottom: -40px;
  font-size: 180px;
  font-weight: 900;
  line-height: 1;
  color: rgba(246, 241, 231, 0.06);
  pointer-events: none;
}

.page-about .about-cta__title {
  margin: 0;
  font-size: clamp(21px, 4vw, 30px);
  font-weight: 900;
  line-height: 1.3;
  letter-spacing: -0.01em;
}

.page-about .about-cta__text {
  margin: 0;
  max-width: 32em;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--body-dim);
}

.page-about .about-cta__links {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 4px;
}

/* ---------- 平板与桌面 ---------- */
@media (min-width: 720px) {
  .page-about .about-partners {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .about-scale {
    padding: 10px 26px 18px;
  }

  .page-about .about-cta__box {
    padding: 32px 28px;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero {
    padding: 34px 0 64px;
  }

  .page-about .about-hero__inner {
    grid-template-columns: minmax(0, 1.35fr) minmax(0, 0.65fr);
    grid-template-areas:
      "crumbs crumbs"
      "eyebrow facts"
      "title facts"
      "lede facts";
    column-gap: 48px;
    row-gap: 14px;
    align-items: start;
  }

  .page-about .about-hero__crumbs {
    grid-area: crumbs;
    margin-bottom: 12px;
  }

  .page-about .about-hero__eyebrow {
    grid-area: eyebrow;
  }

  .page-about .about-hero__title {
    grid-area: title;
  }

  .page-about .about-hero__lede {
    grid-area: lede;
    font-size: 17px;
  }

  .page-about .about-hero__facts {
    grid-area: facts;
    align-self: end;
    margin-top: 0;
  }

  .page-about .about-body {
    grid-template-columns: 220px minmax(0, 1fr);
    gap: 56px;
    padding-block: 56px 72px;
  }

  .page-about .about-index {
    position: sticky;
    top: 96px;
    align-self: start;
  }

  .page-about .about-two-col {
    grid-template-columns: minmax(0, 1.18fr) minmax(0, 0.82fr);
    gap: 36px;
    align-items: start;
  }

  .page-about .about-figure--side {
    margin-top: 6px;
    margin-left: 8px;
  }

  .page-about .about-section {
    padding-block: 38px 48px;
    scroll-margin-top: 110px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-index__link,
  .page-about .about-timeline__summary {
    transition: none;
  }
}

.page-about {
  --w: 1rem;
}