.page-about {
  --about-rule: rgba(18, 28, 58, .12);
  --about-soft-celadon: #DCEAE4;
  --about-soft-coral: #F6DFD6;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  isolation: isolate;
  overflow: hidden;
  background-color: var(--ink-900);
  color: var(--paper-050);
  padding: 34px 0 46px;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  background:
    linear-gradient(112deg, transparent 0 38%, rgba(216, 163, 60, .16) 38% 58%, transparent 58% 100%),
    linear-gradient(112deg, transparent 0 66%, rgba(62, 143, 118, .18) 66% 76%, transparent 76% 100%);
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  right: -70px;
  bottom: -90px;
  z-index: 0;
  width: 240px;
  height: 240px;
  background: var(--gold-500);
  opacity: .1;
  transform: rotate(45deg);
  pointer-events: none;
}

.page-about .about-hero__inner {
  position: relative;
  z-index: 1;
}

.page-about .about-hero__crumb {
  margin-bottom: 20px;
}

.page-about .breadcrumb__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin: 0;
  padding: 0;
  list-style: none;
  font-family: var(--font-data);
  font-size: 12.5px;
  letter-spacing: .06em;
}

.page-about .about-hero__crumb .breadcrumb__list a {
  color: rgba(250, 245, 234, .62);
  text-decoration: none;
}

.page-about .about-hero__crumb .breadcrumb__list a:hover,
.page-about .about-hero__crumb .breadcrumb__list a:focus-visible {
  color: var(--gold-500);
}

.page-about .about-hero__crumb .breadcrumb__list a[aria-current="page"] {
  color: var(--gold-500);
}

.page-about .about-hero__crumb .breadcrumb__sep {
  color: rgba(250, 245, 234, .34);
}

.page-about .about-hero__eyebrow {
  color: var(--gold-500);
  margin: 0 0 14px;
}

.page-about .about-hero__title {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(32px, 7.2vw, 66px);
  line-height: 1.12;
  letter-spacing: -.012em;
  margin: 0 0 20px;
  max-width: 15em;
}

.page-about .about-hero__lede {
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.85;
  color: rgba(250, 245, 234, .82);
  max-width: 46em;
  margin: 0;
}

.page-about .about-hero__strip {
  display: flex;
  flex-wrap: wrap;
  gap: 12px 26px;
  margin: 28px 0 0;
  padding: 20px 0 0;
  list-style: none;
  border-top: 1px solid rgba(250, 245, 234, .16);
}

.page-about .about-hero__chip {
  font-family: var(--font-data);
  font-size: 12.5px;
  letter-spacing: .04em;
  color: rgba(250, 245, 234, .7);
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
}

.page-about .about-hero__chip b {
  font-weight: 700;
  color: var(--gold-500);
  font-size: 14px;
}

/* ---------- 起点与动因 ---------- */
.page-about .about-origin__grid {
  align-items: start;
}

.page-about .about-origin__main p {
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.85;
  color: var(--ink-900);
  margin: 0 0 18px;
}

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

.page-about .about-origin__aside {
  background: var(--indigo-100);
  border-left: 3px solid var(--gold-500);
  border-radius: var(--r-sm);
  padding: 22px 20px;
}

.page-about .about-origin__aside-title {
  font-family: var(--font-ui);
  font-weight: 700;
  font-size: 15px;
  color: var(--ink-900);
  margin: 0 0 16px;
}

.page-about .about-origin__list {
  display: grid;
  gap: 14px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-origin__list li {
  position: relative;
  padding-left: 18px;
  font-family: var(--font-body);
  font-size: 14.5px;
  line-height: 1.72;
  color: var(--indigo-700);
}

.page-about .about-origin__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 8px;
  width: 7px;
  height: 7px;
  background: var(--coral-500);
  transform: rotate(45deg);
}

/* ---------- 版本演进时间轴 ---------- */
.page-about .about-phases__head {
  margin-bottom: 30px;
}

.page-about .about-timeline {
  list-style: none;
  margin: 0 0 34px;
  padding: 0;
}

.page-about .about-node {
  position: relative;
  border-left: 2px solid var(--about-rule);
  padding: 2px 0 30px 24px;
}

.page-about .about-node:last-child {
  border-left-color: transparent;
  padding-bottom: 4px;
}

.page-about .about-node::before {
  content: "";
  position: absolute;
  left: -9px;
  top: 8px;
  width: 16px;
  height: 16px;
  border-radius: 3px;
  transform: rotate(45deg);
  box-shadow: 0 0 0 4px var(--paper-050);
}

.page-about .about-node:nth-child(1)::before { background: #D8A33C; }
.page-about .about-node:nth-child(2)::before { background: #C6A24E; }
.page-about .about-node:nth-child(3)::before { background: #94A478; }
.page-about .about-node:nth-child(4)::before { background: #61997C; }
.page-about .about-node:nth-child(5)::before { background: #3E8F76; }

.page-about .about-node__heading {
  margin: 0;
}

.page-about .about-node__trigger {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 6px 14px;
  width: 100%;
  margin: 0;
  padding: 0;
  background: none;
  border: 0;
  text-align: left;
  cursor: pointer;
  font: inherit;
  color: inherit;
}

.page-about .about-node__trigger:focus-visible {
  outline: 2px solid var(--coral-500);
  outline-offset: 4px;
  border-radius: 4px;
}

.page-about .about-node__ver {
  font-family: var(--font-data);
  font-size: 13px;
  letter-spacing: .08em;
  color: var(--stone-600);
  flex: 0 0 auto;
}

.page-about .about-node__name {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(19px, 3.4vw, 27px);
  line-height: 1.28;
  color: var(--ink-900);
}

.page-about .about-node__trigger .accordion__icon {
  position: relative;
  flex: 0 0 auto;
  margin-left: auto;
  width: 24px;
  height: 24px;
  border-radius: 50%;
  border: 1px solid var(--about-rule);
  transition: border-color .24s var(--ease), background-color .24s var(--ease);
}

.page-about .about-node__trigger .accordion__icon::before,
.page-about .about-node__trigger .accordion__icon::after {
  content: "";
  position: absolute;
  left: 50%;
  top: 50%;
  background: var(--indigo-700);
  transform: translate(-50%, -50%);
}

.page-about .about-node__trigger .accordion__icon::before {
  width: 10px;
  height: 1.5px;
}

.page-about .about-node__trigger .accordion__icon::after {
  width: 1.5px;
  height: 10px;
  transition: transform .24s var(--ease);
}

.page-about .about-node__trigger:hover .accordion__icon {
  border-color: var(--gold-500);
  background: var(--gold-200);
}

.page-about .about-node__trigger[aria-expanded="true"] .accordion__icon::after {
  transform: translate(-50%, -50%) scaleY(0);
}

.page-about .about-node__card {
  max-width: 60em;
}

.page-about .about-node__detail {
  margin-top: 14px;
  font-family: var(--font-body);
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--stone-600);
}

.page-about .about-node__detail p {
  margin: 0;
}

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

.page-about .about-phases__figure {
  margin: 26px 0 0;
}

.page-about .about-phases__figure img {
  display: block;
  width: 100%;
  height: auto;
  border-radius: var(--r-cut);
}

.page-about .about-phases__caption {
  margin-top: 12px;
  font-family: var(--font-ui);
  font-size: 12.5px;
  line-height: 1.7;
  color: var(--stone-600);
  max-width: 48em;
}

/* ---------- 团队分工 ---------- */
.page-about .about-team__grid {
  align-items: start;
}

.page-about .about-team__figure {
  margin: 0;
}

.page-about .about-team__media {
  margin-bottom: 12px;
  border-radius: var(--r-cut);
  overflow: hidden;
}

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

.page-about .about-team__caption {
  font-family: var(--font-ui);
  font-size: 12.5px;
  line-height: 1.7;
  color: var(--stone-600);
}

.page-about .about-team__lede {
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.85;
  color: var(--ink-900);
  margin: 0 0 22px;
}

.page-about .about-team__bars {
  display: flex;
  flex-direction: column;
  gap: 12px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-team__bar {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 18px 16px;
  border-radius: var(--r-sm);
  border-top: 3px solid var(--indigo-700);
  background: var(--indigo-100);
}

.page-about .about-team__bar--edit {
  background: var(--gold-200);
  border-top-color: var(--gold-500);
}

.page-about .about-team__bar--tech {
  background: var(--indigo-100);
  border-top-color: var(--indigo-700);
}

.page-about .about-team__bar--advisor {
  background: var(--about-soft-celadon);
  border-top-color: var(--celadon-500);
}

.page-about .about-team__num {
  font-family: var(--font-data);
  font-size: 30px;
  font-weight: 700;
  line-height: 1;
  color: var(--ink-900);
  display: block;
}

.page-about .about-team__role {
  font-family: var(--font-ui);
  font-size: 15px;
  font-weight: 700;
  color: var(--ink-900);
  display: block;
}

.page-about .about-team__duty {
  font-family: var(--font-body);
  font-size: 13.5px;
  line-height: 1.72;
  color: var(--indigo-700);
  display: block;
  transition: opacity .26s var(--ease);
}

/* ---------- 内容维护 ---------- */
.page-about .about-upkeep__head {
  margin-bottom: 28px;
}

.page-about .about-upkeep__cell {
  border-top: 3px solid var(--gold-500);
  padding: 20px 0 4px;
}

.page-about .about-upkeep__cell--celadon {
  border-top-color: var(--celadon-500);
}

.page-about .about-upkeep__cell--coral {
  border-top-color: var(--coral-500);
}

.page-about .about-upkeep__num {
  display: block;
  font-family: var(--font-data);
  font-size: clamp(28px, 5vw, 42px);
  font-weight: 700;
  line-height: 1.05;
  color: var(--ink-900);
  margin-bottom: 8px;
}

.page-about .about-upkeep__label {
  display: block;
  font-family: var(--font-ui);
  font-size: 14px;
  font-weight: 700;
  letter-spacing: .04em;
  color: var(--indigo-700);
  margin-bottom: 10px;
}

.page-about .about-upkeep__text {
  margin: 0;
  font-family: var(--font-body);
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--stone-600);
  max-width: 26em;
}

/* ---------- 覆盖与协作 ---------- */
.page-about .about-reach__grid {
  align-items: start;
}

.page-about .about-reach__lede {
  font-family: var(--font-body);
  font-size: 16.5px;
  line-height: 1.85;
  color: var(--ink-900);
  margin: 0 0 16px;
}

.page-about .about-reach__stats {
  display: grid;
  gap: 16px 22px;
  margin-top: 24px;
  padding-top: 22px;
  border-top: 1px solid var(--about-rule);
}

.page-about .about-reach__stat {
  border-left: 2px solid var(--moss-400);
  padding-left: 14px;
}

.page-about .about-reach__stat b {
  display: block;
  font-family: var(--font-data);
  font-size: 21px;
  font-weight: 700;
  color: var(--ink-900);
  margin-bottom: 4px;
}

.page-about .about-reach__stat span {
  display: block;
  font-family: var(--font-ui);
  font-size: 13px;
  line-height: 1.6;
  color: var(--stone-600);
}

.page-about .about-reach__media {
  border-radius: var(--r-cut);
  overflow: hidden;
}

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

.page-about .about-reach__caption {
  margin: 12px 0 0;
  font-family: var(--font-ui);
  font-size: 12.5px;
  line-height: 1.7;
  color: var(--stone-600);
}

/* ---------- 备案与运营信息 ---------- */
.page-about .about-legal {
  background: var(--ink-900);
  color: var(--paper-050);
  border-radius: var(--r-cut);
  padding: 28px 22px;
}

.page-about .about-legal__head {
  margin-bottom: 22px;
}

.page-about .about-legal__eyebrow {
  color: var(--gold-500);
}

.page-about .about-legal__title {
  color: var(--paper-050);
}

.page-about .about-legal__grid {
  display: grid;
  gap: 20px 26px;
  margin: 0;
  padding: 0;
}

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

.page-about .about-legal__k {
  display: block;
  font-family: var(--font-ui);
  font-size: 11.5px;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--gold-500);
  margin-bottom: 7px;
}

.page-about .about-legal__v {
  margin: 0;
  font-family: var(--font-body);
  font-size: 14.5px;
  line-height: 1.72;
  color: rgba(250, 245, 234, .88);
  word-break: break-word;
}

.page-about .about-legal__note {
  margin: 24px 0 0;
  padding-top: 18px;
  border-top: 1px solid rgba(250, 245, 234, .16);
  font-family: var(--font-ui);
  font-size: 13.5px;
  line-height: 1.8;
  color: rgba(250, 245, 234, .68);
  max-width: 52em;
}

/* ---------- 后续入口 ---------- */
.page-about .about-next__head {
  margin-bottom: 24px;
}

.page-about .about-next__links {
  display: grid;
  gap: 14px;
}

.page-about .about-next__link {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 22px 54px 22px 20px;
  border-radius: var(--r-cut);
  border-left: 4px solid var(--gold-500);
  background: var(--indigo-100);
  color: var(--ink-900);
  text-decoration: none;
  transition: transform .28s var(--ease), box-shadow .28s var(--ease);
}

.page-about .about-next__link--celadon {
  border-left-color: var(--celadon-500);
  background: var(--about-soft-celadon);
}

.page-about .about-next__link--coral {
  border-left-color: var(--coral-500);
  background: var(--about-soft-coral);
}

.page-about .about-next__link:hover,
.page-about .about-next__link:focus-visible {
  transform: translateY(-4px);
  box-shadow: var(--shadow-2);
}

.page-about .about-next__link:focus-visible {
  outline: 2px solid var(--coral-500);
  outline-offset: 3px;
}

.page-about .about-next__link-title {
  font-family: var(--font-ui);
  font-size: 17px;
  font-weight: 700;
  line-height: 1.4;
}

.page-about .about-next__link-desc {
  font-family: var(--font-body);
  font-size: 14px;
  line-height: 1.72;
  color: var(--indigo-700);
}

.page-about .about-next__link-arrow {
  position: absolute;
  right: 20px;
  top: 50%;
  transform: translateY(-50%);
  font-family: var(--font-data);
  font-size: 20px;
  color: var(--ink-900);
  opacity: .5;
  transition: transform .28s var(--ease), opacity .28s var(--ease);
}

.page-about .about-next__link:hover .about-next__link-arrow,
.page-about .about-next__link:focus-visible .about-next__link-arrow {
  opacity: 1;
  transform: translateY(-50%) translateX(4px);
}

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

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

@media (min-width: 720px) {
  .page-about .about-hero {
    padding: 52px 0 64px;
  }

  .page-about .about-legal {
    padding: 34px 30px;
  }

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

  .page-about .about-team__bars {
    flex-direction: row;
    align-items: stretch;
  }

  .page-about .about-team__bar {
    padding: 20px 16px;
  }

  .page-about .about-team__bar--edit { flex: 12 1 0; }
  .page-about .about-team__bar--tech { flex: 15 1 0; }
  .page-about .about-team__bar--advisor { flex: 11 1 0; }

  .page-about .about-team__duty {
    opacity: .58;
  }

  .page-about .about-team__bar:hover .about-team__duty,
  .page-about .about-team__bar:focus-within .about-team__duty {
    opacity: 1;
  }
}

@media (min-width: 1024px) {
  .page-about .about-node {
    padding: 2px 90px 42px 40px;
  }

  .page-about .about-node:last-child {
    padding-bottom: 6px;
  }

  .page-about .about-node__note {
    display: block;
    position: absolute;
    right: 14px;
    top: 10px;
    writing-mode: vertical-rl;
    font-family: var(--font-ui);
    font-size: 12px;
    letter-spacing: .3em;
    color: var(--stone-600);
    opacity: .62;
  }

  .page-about .about-node::before {
    left: -9px;
    top: 10px;
  }

  .page-about .about-origin__aside {
    padding: 28px 24px;
  }

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

@media (prefers-reduced-motion: reduce) {
  .page-about .about-node__trigger .accordion__icon,
  .page-about .about-node__trigger .accordion__icon::after,
  .page-about .about-team__duty,
  .page-about .about-next__link,
  .page-about .about-next__link-arrow {
    transition: none !important;
  }

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

  .page-about .about-next__link:hover .about-next__link-arrow,
  .page-about .about-next__link:focus-visible .about-next__link-arrow {
    transform: translateY(-50%);
  }
}