.page-about {
  --about-gap: clamp(16px, 3vw, 28px);
  background: var(--paper-bg);
  color: var(--ink);
  font-family: var(--font-body);
  line-height: 1.75;
}

.page-about a {
  color: var(--green-deep);
}

.page-about a:focus-visible,
.page-about summary:focus-visible {
  outline: 2px solid var(--amber);
  outline-offset: 3px;
}

.page-about .breadcrumbs {
  padding-top: clamp(18px, 3vw, 30px);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding: clamp(24px, 4vw, 44px) 0 clamp(36px, 6vw, 68px);
  border-bottom: 2px solid var(--mist);
}

.page-about .about-hero__inner {
  display: grid;
  gap: clamp(24px, 4vw, 44px);
  grid-template-columns: minmax(0, 1fr);
}

.page-about .about-hero__lead .eyebrow {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--green);
}

.page-about .about-hero__lead h1 {
  margin: 0 0 18px;
  font-family: var(--font-head);
  font-size: clamp(30px, 6.2vw, 56px);
  font-weight: 900;
  line-height: 1.12;
  letter-spacing: -0.01em;
  color: var(--ink);
}

.page-about .about-hero__lede {
  margin: 0 0 24px;
  max-width: 60ch;
  font-size: clamp(15px, 1.6vw, 17px);
  color: var(--ink-2);
}

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

.page-about .about-hero__panel {
  align-self: end;
  padding: 20px 22px;
  background: var(--ink);
  color: var(--paper);
  border: 2px solid var(--ink);
  box-shadow: var(--hard-shadow);
}

.page-about .about-hero__panel-label {
  margin: 0 0 14px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.22em;
  color: var(--green-lite);
}

.page-about .about-hero__stats {
  display: grid;
  gap: 12px;
  margin: 0;
}

.page-about .about-hero__stat {
  padding-bottom: 12px;
  border-bottom: 1px solid rgba(250, 249, 244, 0.18);
}

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

.page-about .about-hero__stat dt {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--green-lite);
}

.page-about .about-hero__stat dd {
  margin: 3px 0 0;
  font-size: 15px;
  color: var(--paper);
}

.page-about .about-hero__stat .num {
  font-family: var(--font-mono);
  font-size: 22px;
  font-weight: 700;
  color: var(--amber);
  margin-right: 5px;
}

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

/* ---------- 章节头 ---------- */
.page-about .about-sec-head {
  margin-bottom: clamp(22px, 4vw, 38px);
  padding-top: 16px;
  border-top: 2px solid var(--ink);
}

.page-about .about-sec-num {
  display: inline-block;
  margin-bottom: 6px;
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.18em;
  color: var(--green);
}

.page-about .about-sec-head h2 {
  margin: 0 0 10px;
  font-family: var(--font-head);
  font-size: clamp(23px, 4.4vw, 38px);
  font-weight: 900;
  line-height: 1.2;
  color: var(--ink);
}

.page-about .about-sec-head p {
  margin: 0;
  max-width: 66ch;
  color: var(--ink-2);
}

/* ---------- 时间线 ---------- */
.page-about .about-timeline {
  padding: clamp(34px, 6vw, 68px) 0;
  background: var(--paper-bg);
}

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

.page-about .about-timeline__rail {
  list-style: none;
  margin: 0;
  padding: 0;
  border-left: 2px solid var(--mist);
  display: grid;
  gap: 20px;
}

.page-about .about-timeline__rail li {
  position: relative;
  padding-left: 24px;
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: 0.02em;
}

.page-about .about-timeline__rail li::before {
  content: "";
  position: absolute;
  left: -8px;
  top: 7px;
  width: 12px;
  height: 12px;
  background: var(--paper);
  border: 2px solid var(--green);
  border-radius: 50%;
}

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

.page-about .about-timeline__rail a:hover {
  color: var(--green-deep);
  text-decoration: underline;
  text-underline-offset: 4px;
}

.page-about .about-timeline__cards {
  display: grid;
  gap: var(--about-gap);
}

.page-about .about-stage {
  scroll-margin-top: 110px;
  padding: clamp(18px, 3vw, 28px);
  background: var(--paper);
  border: 2px solid var(--ink);
  box-shadow: var(--soft-shadow);
}

.page-about .about-stage__year {
  display: inline-block;
  margin: 0 0 10px;
  padding: 3px 9px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--ink);
  background: var(--green-lite);
  border: 2px solid var(--ink);
}

.page-about .about-stage h3 {
  margin: 0 0 10px;
  font-family: var(--font-head);
  font-size: clamp(19px, 2.6vw, 24px);
  font-weight: 900;
  line-height: 1.3;
}

.page-about .about-stage p {
  margin: 0 0 12px;
  color: var(--ink-2);
  font-size: 15.5px;
}

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

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

.page-about .about-stage__figure img,
.page-about .about-team__figure img,
.page-about .about-flow__figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

.page-about .about-stage__figure figcaption,
.page-about .about-team__figure figcaption,
.page-about .about-flow__figure figcaption {
  margin-top: 8px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.06em;
  color: var(--moss);
}

.page-about .about-stage__links a {
  font-weight: 700;
  text-underline-offset: 4px;
}

/* ---------- 团队 ---------- */
.page-about .about-team {
  padding: clamp(34px, 6vw, 68px) 0;
  background: var(--paper);
  border-top: 2px solid var(--ink);
  border-bottom: 2px solid var(--ink);
}

.page-about .about-team__figure {
  margin: 0 0 clamp(22px, 4vw, 34px);
}

.page-about .about-team__units {
  display: grid;
  gap: 14px;
  grid-template-columns: minmax(0, 1fr);
}

.page-about .about-unit {
  background: var(--paper-bg);
  border: 2px solid var(--ink);
  box-shadow: 4px 4px 0 var(--mist);
  transition: background-color 160ms ease, box-shadow 160ms ease;
}

.page-about .about-unit:hover,
.page-about .about-unit[open] {
  background: var(--mist);
}

.page-about .about-unit summary {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 15px 16px;
  cursor: pointer;
  list-style: none;
  font-family: var(--font-head);
  font-size: 16px;
  font-weight: 700;
  color: var(--ink);
}

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

.page-about .about-unit summary::after {
  content: "+";
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 18px;
  font-weight: 700;
  color: var(--green-deep);
}

.page-about .about-unit[open] summary::after {
  content: "−";
}

.page-about .about-unit__idx {
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--green-deep);
}

.page-about .about-unit__body {
  padding: 0 16px 16px;
}

.page-about .about-unit__body ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 8px;
}

.page-about .about-unit__body li {
  position: relative;
  padding-left: 16px;
  font-size: 14.5px;
  line-height: 1.7;
  color: var(--ink-2);
}

.page-about .about-unit__body li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 11px;
  width: 9px;
  height: 2px;
  background: var(--green);
}

.page-about .about-team__support {
  display: grid;
  gap: 14px;
  margin-top: clamp(20px, 3vw, 28px);
  padding: clamp(18px, 3vw, 26px);
  background: var(--ink-2);
  color: var(--paper);
  border: 2px solid var(--ink);
  box-shadow: var(--hard-shadow);
}

.page-about .about-team__support-k {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 44px;
  font-weight: 700;
  line-height: 1;
  color: var(--amber);
}

.page-about .about-team__support-text h3 {
  margin: 0 0 8px;
  font-family: var(--font-head);
  font-size: 19px;
  font-weight: 900;
}

.page-about .about-team__support-text p {
  margin: 0 0 10px;
  font-size: 14.5px;
  color: var(--mist);
}

.page-about .about-team__support-link {
  margin: 0;
}

.page-about .about-team__support-link a {
  color: var(--green-lite);
  font-weight: 700;
  text-underline-offset: 4px;
}

/* ---------- 四步流程 ---------- */
.page-about .about-flow {
  padding: clamp(34px, 6vw, 68px) 0;
  background: var(--paper-bg);
}

.page-about .about-flow__figure {
  margin: 0 0 clamp(22px, 4vw, 34px);
}

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

.page-about .about-step {
  padding: 18px 18px 20px;
  background: var(--paper);
  border: 2px solid var(--ink);
  box-shadow: 4px 4px 0 var(--mist);
  transition: background-color 160ms ease, box-shadow 160ms ease;
}

.page-about .about-step:hover {
  background: var(--mist);
  box-shadow: 2px 2px 0 var(--ink);
}

.page-about .about-step__idx {
  margin: 0 0 8px;
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.14em;
  color: var(--green-deep);
}

.page-about .about-step h3 {
  margin: 0 0 8px;
  font-family: var(--font-head);
  font-size: 20px;
  font-weight: 900;
}

.page-about .about-step p {
  margin: 0;
  font-size: 14.5px;
  color: var(--ink-2);
}

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

/* ---------- 生态与记录 ---------- */
.page-about .about-eco {
  padding: clamp(34px, 6vw, 68px) 0;
  background: var(--paper);
  border-top: 2px solid var(--ink);
  border-bottom: 2px solid var(--ink);
}

.page-about .about-records {
  display: grid;
  gap: 1px;
  grid-template-columns: minmax(0, 1fr);
  background: var(--mist);
  border: 2px solid var(--ink);
  box-shadow: var(--soft-shadow);
}

.page-about .about-record {
  padding: 20px;
  background: var(--paper);
}

.page-about .about-record__num {
  margin: 0 0 6px;
  font-family: var(--font-mono);
  font-size: clamp(32px, 6vw, 42px);
  font-weight: 700;
  line-height: 1;
  color: var(--ink);
}

.page-about .about-record__unit {
  font-size: 18px;
  margin-left: 2px;
  color: var(--green-deep);
}

.page-about .about-record__label {
  margin: 0 0 6px;
  font-size: 15px;
  font-weight: 700;
  color: var(--ink-2);
}

.page-about .about-record__note {
  margin: 0;
  font-size: 13.5px;
  line-height: 1.65;
  color: var(--moss);
}

.page-about .about-eco__aside {
  margin-top: clamp(20px, 3vw, 30px);
  padding: clamp(18px, 3vw, 26px);
  background: var(--paper-bg);
  border-left: 6px solid var(--amber);
  border-top: 1px solid var(--mist);
  border-right: 1px solid var(--mist);
  border-bottom: 1px solid var(--mist);
}

.page-about .about-eco__aside h3 {
  margin: 0 0 8px;
  font-family: var(--font-head);
  font-size: 18px;
  font-weight: 900;
}

.page-about .about-eco__aside p {
  margin: 0;
  max-width: 70ch;
  font-size: 14.5px;
  color: var(--ink-2);
}

/* ---------- 原则与出口 ---------- */
.page-about .about-principles {
  padding: clamp(34px, 6vw, 68px) 0 clamp(44px, 7vw, 84px);
  background: var(--paper-bg);
}

.page-about .about-principles__list {
  list-style: none;
  margin: 0 0 clamp(24px, 4vw, 38px);
  padding: 0;
  display: grid;
  gap: 0;
  border-top: 2px solid var(--ink);
}

.page-about .about-principles__list li {
  display: grid;
  grid-template-columns: 38px minmax(0, 1fr);
  gap: 12px;
  padding: 18px 0;
  border-bottom: 1px solid var(--mist);
}

.page-about .about-principles__idx {
  font-family: var(--font-mono);
  font-size: 15px;
  font-weight: 700;
  color: var(--amber);
  padding-top: 2px;
}

.page-about .about-principles__list h3 {
  margin: 0 0 6px;
  font-family: var(--font-head);
  font-size: 18px;
  font-weight: 900;
}

.page-about .about-principles__list p {
  margin: 0;
  max-width: 64ch;
  font-size: 14.5px;
  color: var(--ink-2);
}

.page-about .about-principles__next {
  padding: clamp(18px, 3vw, 26px);
  border: 2px solid var(--ink);
  background: var(--paper);
  box-shadow: var(--hard-shadow);
}

.page-about .about-principles__next-title {
  margin: 0 0 14px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--green-deep);
}

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

.page-about .about-principles__links a {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 4px 12px;
  padding: 12px 14px;
  background: var(--paper-bg);
  border: 2px solid var(--ink);
  color: var(--ink);
  font-weight: 700;
  text-decoration: none;
  transition: background-color 150ms ease, border-color 150ms ease;
}

.page-about .about-principles__links a:hover {
  background: var(--green-lite);
  border-color: var(--green-deep);
}

.page-about .about-principles__links span {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 400;
  color: var(--moss);
}

/* ---------- 断点 ---------- */
@media (min-width: 640px) {
  .page-about .about-team__units {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-about .about-team__support {
    grid-template-columns: auto minmax(0, 1fr);
    align-items: center;
    gap: 20px;
  }

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

@media (min-width: 900px) {
  .page-about .about-hero__inner {
    grid-template-columns: minmax(0, 1.45fr) minmax(0, 0.55fr);
    align-items: end;
  }

  .page-about .about-timeline__grid {
    grid-template-columns: 210px minmax(0, 1fr);
    align-items: start;
  }

  .page-about .about-timeline__rail {
    position: sticky;
    top: 104px;
  }

  .page-about .about-stage:nth-child(even) {
    margin-left: clamp(20px, 5vw, 64px);
  }

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

  .page-about .about-flow__track {
    grid-template-columns: minmax(0, 1fr) auto minmax(0, 1fr) auto minmax(0, 1fr) auto minmax(0, 1fr);
    gap: 10px 0;
    align-items: stretch;
  }

  .page-about .about-flow__arrow {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 30px;
    color: var(--green);
  }

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

@media (min-width: 1120px) {
  .page-about .about-hero__rotate {
    display: block;
    position: absolute;
    right: 8px;
    top: 96px;
    writing-mode: vertical-rl;
    font-family: var(--font-mono);
    font-size: 11px;
    letter-spacing: 0.36em;
    color: var(--moss);
    pointer-events: none;
  }
}

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