.page-about {
  position: relative;
  background: var(--paper);
  color: var(--ink);
  padding-bottom: 72px;
  overflow-x: clip;
}

/* 阅读进度条：仅在支持滚动驱动动画的浏览器中随滚动推进 */
.page-about .about-progress {
  position: fixed;
  top: 0;
  right: 0;
  left: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--grass) 0%, var(--grass-2) 38%, var(--blue) 74%, var(--orange) 100%);
  transform: scaleX(0);
  transform-origin: 0 50%;
  pointer-events: none;
  z-index: 70;
}

@supports (animation-timeline: scroll()) {
  @media (prefers-reduced-motion: no-preference) {
    .page-about .about-progress {
      animation: about-progress-grow linear both;
      animation-timeline: scroll(root block);
    }
  }
}

@keyframes about-progress-grow {
  from { transform: scaleX(0); }
  to { transform: scaleX(1); }
}

/* ---------- 首屏框景 ---------- */
.page-about .about-hero {
  padding: 104px 0 8px;
}

.page-about .about-hero .breadcrumbs {
  margin-bottom: 18px;
}

.page-about .about-hero__frame {
  position: relative;
  padding: 34px 24px 32px;
  border-radius: var(--r-lg);
  background:
    radial-gradient(120% 100% at 100% 0%, var(--grass-mist) 0%, transparent 58%),
    linear-gradient(180deg, #ffffff 0%, var(--paper) 100%);
  overflow: hidden;
}

.page-about .about-hero__spec {
  display: none;
}

.page-about .about-hero__stamp {
  position: absolute;
  right: 14px;
  bottom: -18px;
  font-family: var(--font-mono);
  font-size: clamp(76px, 13vw, 148px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.05em;
  color: rgba(14, 124, 102, 0.08);
  pointer-events: none;
  user-select: none;
}

.page-about .about-hero__eyebrow {
  position: relative;
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.26em;
  color: var(--grass);
}

.page-about .about-hero__title {
  position: relative;
  margin: 14px 0 0;
  font-family: var(--font-sans);
  font-weight: 900;
  font-size: clamp(32px, 5.4vw, 56px);
  line-height: 1.1;
  letter-spacing: -0.02em;
  color: var(--navy);
}

.page-about .about-hero__lead {
  position: relative;
  max-width: 62ch;
  margin: 20px 0 0;
  font-size: 16px;
  line-height: 1.85;
  color: var(--ink);
}

.page-about .about-hero__facts {
  position: relative;
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--gap-sm);
  margin: 30px 0 0;
  padding: 22px 0 0;
  list-style: none;
  border-top: 1px solid var(--line);
}

.page-about .about-fact__num {
  display: block;
  font-family: var(--font-mono);
  font-size: 24px;
  font-weight: 600;
  line-height: 1.2;
  color: var(--grass);
}

.page-about .about-fact__num--blue { color: var(--navy); }
.page-about .about-fact__num--orange { color: var(--orange-deep); }

.page-about .about-fact__label {
  display: block;
  margin-top: 6px;
  font-size: 13px;
  line-height: 1.6;
  color: var(--ink-mid);
}

/* ---------- 主体两栏 ---------- */
.page-about .about-body {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--gap-lg);
  align-items: start;
  padding-top: 56px;
}

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

.page-about .about-section {
  margin-bottom: 56px;
}

.page-about .about-section:last-of-type {
  margin-bottom: 0;
}

.page-about .about-section__head {
  margin-bottom: 24px;
}

.page-about .about-section__kicker {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.3em;
  color: var(--grass);
}

.page-about .about-section__title {
  margin: 0;
  font-family: var(--font-sans);
  font-weight: 800;
  font-size: clamp(24px, 3.4vw, 36px);
  line-height: 1.22;
  letter-spacing: -0.01em;
  color: var(--navy);
}

.page-about .about-section__lead {
  max-width: 58ch;
  margin: 14px 0 0;
  font-size: 16px;
  line-height: 1.8;
  color: var(--ink-mid);
}

/* ---------- 起点 ---------- */
.page-about .about-begin {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--gap-md);
  padding: 26px 22px 24px;
  border-radius: var(--r-md);
  background: var(--glass);
  border: 1px solid var(--line-soft);
  border-left: 4px solid var(--grass);
  box-shadow: var(--shadow-sm);
}

.page-about .about-begin__text p {
  margin: 0 0 1em;
  font-size: 16px;
  line-height: 1.85;
}

.page-about .about-begin__text p:last-child {
  margin-bottom: 0;
}

.page-about .about-begin__media {
  margin: 0;
  border-radius: var(--r-sm);
  overflow: hidden;
  background: var(--paper-deep);
}

/* ---------- 时间线 ---------- */
.page-about .about-timeline {
  position: relative;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 9px;
  top: 14px;
  bottom: 14px;
  width: 2px;
  border-radius: 2px;
  background: linear-gradient(180deg, var(--grass) 0%, var(--blue) 58%, var(--orange) 100%);
}

.page-about .about-timeline__item {
  position: relative;
  padding: 0 0 34px 42px;
  scroll-margin-top: 130px;
}

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

.page-about .about-timeline__item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 4px;
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background: var(--paper);
  border: 3px solid var(--grass);
  box-shadow: 0 0 0 4px var(--paper);
}

.page-about .about-timeline__item:nth-child(2)::before { border-color: var(--grass-2); }
.page-about .about-timeline__item:nth-child(3)::before { border-color: var(--blue); }
.page-about .about-timeline__item:nth-child(4)::before { border-color: var(--orange); }

.page-about .about-timeline__year {
  display: inline-block;
  margin-bottom: 10px;
  padding: 3px 12px;
  border-radius: var(--r-pill);
  background: rgba(14, 124, 102, 0.12);
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.14em;
  color: var(--grass);
}

.page-about .about-timeline__item:nth-child(4) .about-timeline__year {
  background: rgba(242, 107, 42, 0.12);
  color: var(--orange-deep);
}

.page-about .about-timeline__title {
  margin: 0 0 8px;
  font-size: 19px;
  font-weight: 700;
  line-height: 1.4;
  color: var(--navy);
}

.page-about .about-timeline__item p {
  margin: 0;
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--ink);
}

/* ---------- 团队 ---------- */
.page-about .about-team {
  position: relative;
  padding: 30px 22px 28px;
  border-radius: var(--r-lg);
  background:
    radial-gradient(90% 70% at 100% 0%, rgba(23, 163, 127, 0.28) 0%, transparent 60%),
    var(--navy);
  color: var(--paper);
  overflow: hidden;
}

.page-about .about-team .about-section__kicker { color: var(--grass-soft); }
.page-about .about-team .about-section__title { color: #ffffff; }
.page-about .about-team .about-section__lead { color: rgba(246, 241, 231, 0.78); }

.page-about .about-team__media {
  margin: 0 0 22px;
  border-radius: var(--r-sm);
  overflow: hidden;
  background: rgba(255, 255, 255, 0.06);
}

.page-about .about-team .media__label {
  color: rgba(246, 241, 231, 0.7);
}

.page-about .about-team__chips {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 18px;
}

.page-about .about-team .chip {
  background: rgba(255, 255, 255, 0.08);
  border-color: rgba(255, 255, 255, 0.24);
  color: rgba(246, 241, 231, 0.86);
}

.page-about .about-team .chip:hover {
  background: rgba(255, 255, 255, 0.16);
  color: #ffffff;
}

.page-about .about-team .chip[aria-selected="true"] {
  background: var(--grass-2);
  border-color: var(--grass-2);
  color: #ffffff;
}

.page-about .about-team__panels {
  display: grid;
  gap: 12px;
}

.page-about .about-team__panel {
  padding: 18px 20px 16px;
  border-radius: var(--r-sm);
  border-left: 3px solid var(--grass-soft);
  background: rgba(255, 255, 255, 0.07);
}

.page-about .about-team__panel-title {
  margin: 0 0 8px;
  font-size: 15px;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--grass-soft);
}

.page-about .about-team__panel p {
  margin: 0;
  font-size: 15px;
  line-height: 1.85;
  color: rgba(246, 241, 231, 0.9);
}

/* ---------- 数据来源 ---------- */
.page-about .about-sources__wrap {
  padding: 26px 20px 24px;
  border-radius: var(--r-md);
  background: var(--blue-mist);
  border: 1px solid rgba(46, 134, 222, 0.2);
}

.page-about .about-sources .about-section__kicker { color: var(--blue); }

.page-about .about-rhythm__scroll {
  overflow-x: auto;
  margin: 4px -6px 22px;
  padding: 0 6px 8px;
  scrollbar-width: thin;
}

.page-about .about-rhythm {
  display: block;
  width: 100%;
  min-width: 620px;
  height: auto;
}

.page-about .about-rhythm__axis {
  stroke: rgba(15, 61, 110, 0.24);
  stroke-width: 2;
  stroke-dasharray: 8 9;
}

.page-about .about-rhythm__dot {
  stroke: #ffffff;
  stroke-width: 3;
}

.page-about .about-rhythm__dot--a { fill: var(--grass); }
.page-about .about-rhythm__dot--b { fill: var(--blue); }
.page-about .about-rhythm__dot--c { fill: var(--navy); }
.page-about .about-rhythm__dot--d { fill: var(--orange); }

.page-about .about-rhythm__label {
  font-family: var(--font-sans);
  font-size: 16px;
  font-weight: 700;
  fill: var(--navy);
}

.page-about .about-rhythm__sub {
  font-family: var(--font-mono);
  font-size: 13px;
  fill: var(--ink-mid);
}

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

.page-about .about-sources__list li {
  position: relative;
  padding-left: 22px;
  font-size: 15.5px;
  line-height: 1.8;
  color: var(--ink);
}

.page-about .about-sources__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.66em;
  width: 8px;
  height: 8px;
  border-radius: 2px;
  background: var(--blue);
  transform: rotate(45deg);
}

.page-about .about-sources__list strong {
  font-weight: 700;
  color: var(--navy);
}

/* ---------- 服务对象 ---------- */
.page-about .about-audience__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--gap-sm);
}

.page-about .about-audience__card {
  padding: 20px 20px 18px;
  border-radius: var(--r-sm);
  background: #ffffff;
  border: 1px solid var(--line-soft);
  border-top: 3px solid var(--grass);
  box-shadow: var(--shadow-sm);
  transition: transform 0.24s var(--ease), box-shadow 0.24s var(--ease);
}

.page-about .about-audience__card:nth-child(2) { border-top-color: var(--blue); }
.page-about .about-audience__card:nth-child(3) { border-top-color: var(--navy); }
.page-about .about-audience__card:nth-child(4) { border-top-color: var(--orange); }

.page-about .about-audience__card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.page-about .about-audience__title {
  margin: 0 0 10px;
  font-size: 17px;
  font-weight: 700;
  line-height: 1.45;
  color: var(--navy);
}

.page-about .about-audience__card p {
  margin: 0;
  font-size: 15px;
  line-height: 1.85;
  color: var(--ink);
}

/* ---------- 合作与覆盖 ---------- */
.page-about .about-partners__inner {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--gap-md);
  align-items: start;
}

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

.page-about .about-partners__facts li {
  padding: 14px 16px;
  border-radius: var(--r-sm);
  background: var(--grass-mist);
  font-size: 15px;
  line-height: 1.75;
  color: var(--ink);
}

.page-about .about-partners__facts b {
  display: block;
  margin-bottom: 4px;
  font-family: var(--font-mono);
  font-size: 16px;
  font-weight: 600;
  letter-spacing: 0.02em;
  color: var(--grass);
}

.page-about .about-partners__media {
  margin: 0;
  border-radius: var(--r-md);
  overflow: hidden;
  background: var(--navy);
}

/* ---------- 原则 ---------- */
.page-about .about-principles__list {
  counter-reset: pr;
  display: grid;
  gap: 14px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-principle {
  counter-increment: pr;
  position: relative;
  padding: 18px 20px 16px 66px;
  border-radius: var(--r-sm);
  background: var(--paper-deep);
  border: 1px solid var(--line-soft);
}

.page-about .about-principle::before {
  content: counter(pr, decimal-leading-zero);
  position: absolute;
  left: 20px;
  top: 17px;
  font-family: var(--font-mono);
  font-size: 22px;
  font-weight: 600;
  line-height: 1;
  color: var(--grass);
  opacity: 0.75;
}

.page-about .about-principle__title {
  margin: 0 0 8px;
  font-size: 17px;
  font-weight: 700;
  color: var(--navy);
}

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

/* ---------- 下一步 ---------- */
.page-about .about-next {
  margin-top: 56px;
  padding: 28px 22px 26px;
  border-radius: var(--r-lg);
  background: linear-gradient(135deg, var(--grass) 0%, var(--navy) 100%);
  color: #ffffff;
}

.page-about .about-next__title {
  margin: 0 0 8px;
  font-size: clamp(22px, 3vw, 30px);
  font-weight: 800;
  line-height: 1.25;
  color: #ffffff;
}

.page-about .about-next__lead {
  margin: 0 0 22px;
  font-size: 15px;
  line-height: 1.7;
  color: rgba(255, 255, 255, 0.82);
}

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

.page-about .about-next__link {
  display: block;
  padding: 16px 16px 14px;
  border-radius: var(--r-sm);
  background: rgba(255, 255, 255, 0.1);
  border: 1px solid rgba(255, 255, 255, 0.22);
  text-decoration: none;
  transition: background 0.24s var(--ease), transform 0.24s var(--ease);
}

.page-about .about-next__link:hover,
.page-about .about-next__link:focus-visible {
  background: rgba(255, 255, 255, 0.22);
  transform: translateY(-2px);
}

.page-about .about-next__link-title {
  display: block;
  font-size: 16px;
  font-weight: 700;
  color: #ffffff;
}

.page-about .about-next__link-desc {
  display: block;
  margin-top: 6px;
  font-size: 13px;
  line-height: 1.6;
  color: rgba(255, 255, 255, 0.8);
}

/* ---------- 右侧刻度尺 ---------- */
.page-about .about-rail {
  display: none;
}

.page-about .about-rail__label {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.3em;
  color: var(--ink-mid);
}

.page-about .about-rail__list {
  margin: 0;
  padding: 0 0 0 18px;
  list-style: none;
  border-left: 1px solid var(--line);
}

.page-about .about-rail__item {
  position: relative;
}

.page-about .about-rail__link {
  position: relative;
  display: block;
  padding: 9px 0 9px 14px;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.08em;
  color: var(--ink-mid);
  text-decoration: none;
  transition: color 0.2s var(--ease), padding-left 0.2s var(--ease);
}

.page-about .about-rail__link::before {
  content: "";
  position: absolute;
  left: -18px;
  top: 50%;
  width: 10px;
  height: 2px;
  background: currentColor;
  transform: translateY(-50%);
  transition: width 0.2s var(--ease), background 0.2s var(--ease);
}

.page-about .about-rail__link:hover,
.page-about .about-rail__link:focus-visible {
  color: var(--grass);
  padding-left: 19px;
}

.page-about .about-rail__link:hover::before,
.page-about .about-rail__link:focus-visible::before {
  width: 20px;
  background: var(--orange);
}

/* ---------- 图片基础 ---------- */
.page-about .media img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.page-about .media {
  position: relative;
}

/* ---------- 响应式 ---------- */
@media (min-width: 600px) {
  .page-about .about-hero__facts {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: var(--gap-md);
  }

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

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

@media (min-width: 760px) {
  .page-about .about-hero {
    padding-top: 118px;
  }

  .page-about .about-hero__frame {
    padding: 44px 44px 40px 62px;
  }

  .page-about .about-hero__spec {
    display: block;
    position: absolute;
    left: 20px;
    top: 46%;
    transform: translateY(-50%) rotate(180deg);
    writing-mode: vertical-rl;
    font-family: var(--font-mono);
    font-size: 11px;
    letter-spacing: 0.3em;
    color: var(--ink-mid);
    white-space: nowrap;
  }

  .page-about .about-begin {
    grid-template-columns: 1.15fr 0.85fr;
    align-items: center;
    padding: 30px 28px 28px 30px;
  }

  .page-about .about-team {
    padding: 38px 36px 34px;
  }

  .page-about .about-sources__wrap {
    padding: 32px 30px 30px;
  }

  .page-about .about-partners__inner {
    grid-template-columns: 1fr 1fr;
    gap: var(--gap-lg);
  }

  .page-about .about-next {
    padding: 36px 34px 34px;
  }
}

@media (min-width: 1024px) {
  .page-about .about-body {
    grid-template-columns: minmax(0, 1fr) 168px;
  }

  .page-about .about-rail {
    display: block;
    position: sticky;
    top: 118px;
    align-self: start;
  }

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

/* ---------- 动效降级 ---------- */
@media (prefers-reduced-motion: reduce) {
  .page-about .about-audience__card,
  .page-about .about-next__link,
  .page-about .about-rail__link {
    transition: none;
  }

  .page-about .about-audience__card:hover,
  .page-about .about-next__link:hover,
  .page-about .about-next__link:focus-visible {
    transform: none;
  }
}