.page-about {
  --about-measure: 34em;
  --about-gap: 32px;
}

@media (min-width: 900px) {
  .page-about {
    --about-gap: 48px;
  }
}

/* ---------- 面包屑与首屏 ---------- */

.page-about .crumbs {
  padding-top: 22px;
}

.page-about .about-hero {
  padding-block: 26px 56px;
}

.page-about .about-hero__grid {
  display: grid;
  gap: 40px;
}

.page-about .about-hero__title {
  margin: 14px 0 20px;
  font-size: clamp(2.2rem, 7.4vw, 4.25rem);
  line-height: 1.04;
  letter-spacing: -0.02em;
  font-weight: 900;
  color: var(--paper-white);
}

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

.page-about .about-hero__lede {
  max-width: 42em;
  color: rgba(247, 243, 234, 0.8);
}

.page-about .about-hero__aside {
  display: grid;
  gap: 22px;
}

.page-about .vertical-note {
  display: none;
}

.page-about .about-facts {
  list-style: none;
  margin: 0;
  padding: 22px 0 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 20px 18px;
  border-top: 1px solid var(--line);
}

.page-about .about-facts__item {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.page-about .about-facts__num {
  font-size: clamp(1.5rem, 4.4vw, 2rem);
  font-weight: 800;
  line-height: 1;
  color: var(--gold);
}

.page-about .about-facts__label {
  font-size: 13px;
  line-height: 1.6;
  color: var(--slate);
}

@media (min-width: 900px) {
  .page-about .about-hero {
    padding-block: 40px 88px;
  }

  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
    gap: 56px;
    align-items: start;
  }

  .page-about .about-hero__aside {
    display: flex;
    gap: 26px;
    align-items: flex-start;
  }

  .page-about .vertical-note {
    display: block;
    flex: none;
  }

  .page-about .about-facts {
    flex: 1 1 auto;
  }

  .page-about .about-br {
    display: inline;
  }
}

/* ---------- 章节骨架 ---------- */

.page-about .about-chapter {
  padding-block: 60px;
}

.page-about .about-chapter__head {
  position: relative;
  margin-bottom: 36px;
}

.page-about .about-chapter__title {
  margin: 12px 0 0;
  font-size: clamp(1.85rem, 5.4vw, 3.1rem);
  line-height: 1.08;
  letter-spacing: -0.02em;
  font-weight: 900;
}

.page-about .section--paper {
  color: var(--ink);
}

.page-about .section--paper .about-chapter__title {
  color: var(--ink);
}

.page-about .section--paper .eyebrow {
  color: var(--agate);
}

.page-about .section--night .about-chapter__title {
  color: var(--paper-white);
}

.page-about .about-measure {
  max-width: var(--about-measure);
  display: grid;
  gap: 18px;
}

.page-about .about-measure p {
  margin: 0;
  font-size: 17px;
  line-height: 1.85;
}

.page-about .about-inline-link {
  color: var(--agate);
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
  transition: color 160ms var(--ease);
}

.page-about .about-inline-link:hover,
.page-about .about-inline-link:focus-visible {
  color: var(--ink);
}

@media (min-width: 1024px) {
  .page-about .about-chapter {
    padding-block: 104px;
  }

  .page-about .about-chapter__head {
    padding-right: 72px;
    min-height: 104px;
    margin-bottom: 52px;
  }

  .page-about .about-chapter__note {
    position: absolute;
    right: 0;
    top: 0;
  }
}

/* ---------- 分层清单 ---------- */

.page-about .layer-list {
  list-style: none;
  margin: 34px 0 0;
  padding: 0;
  max-width: 44em;
  border-top: 1px solid rgba(27, 31, 39, 0.18);
}

.page-about .layer-list__item {
  display: grid;
  grid-template-columns: 1.9rem minmax(0, 1fr);
  gap: 16px;
  padding: 20px 0;
  border-bottom: 1px solid rgba(27, 31, 39, 0.18);
}

.page-about .layer-list__no {
  font-size: 1.05rem;
  font-weight: 800;
  line-height: 1.6;
  color: var(--slate);
}

.page-about .layer-list__title {
  margin: 0 0 8px;
  font-size: 1.08rem;
  font-weight: 800;
  color: var(--ink);
}

.page-about .layer-list__text {
  margin: 0;
  font-size: 15.5px;
  line-height: 1.82;
  color: rgba(27, 31, 39, 0.78);
}

/* ---------- 团队 ---------- */

.page-about .about-team__media {
  margin: 0 0 34px;
}

.page-about .about-team__media .media__img,
.page-about .about-tl__media .media__img,
.page-about .about-coop__media .media__img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
  border: 1px solid var(--line);
}

.page-about .duty-grid {
  display: grid;
  gap: 20px;
}

.page-about .duty-card {
  position: relative;
  padding: 26px 22px 22px;
  border: 1px solid var(--line);
  background: linear-gradient(155deg, rgba(245, 166, 35, 0.08), rgba(10, 17, 34, 0.55) 62%);
  clip-path: polygon(18px 0, 100% 0, 100% calc(100% - 18px), calc(100% - 18px) 100%, 0 100%, 0 18px);
  transition: transform 180ms var(--ease), background 180ms var(--ease);
}

.page-about .duty-card:hover,
.page-about .duty-card:focus-within {
  transform: translateY(-2px);
  background: linear-gradient(155deg, rgba(245, 166, 35, 0.16), rgba(10, 17, 34, 0.6) 62%);
}

.page-about .duty-card:focus-visible {
  outline: 2px solid var(--glow);
  outline-offset: -2px;
}

.page-about .duty-card__no {
  display: block;
  font-size: clamp(2.4rem, 7vw, 3.4rem);
  font-weight: 800;
  line-height: 1;
  color: var(--gold);
}

.page-about .duty-card__role {
  margin: 10px 0 12px;
  font-size: 1.02rem;
  font-weight: 700;
  letter-spacing: 0.16em;
  color: var(--paper-white);
}

.page-about .duty-card__text {
  margin: 0;
  font-size: 15px;
  line-height: 1.8;
  color: rgba(247, 243, 234, 0.78);
}

.page-about .duty-card__more {
  max-height: 0;
  overflow: hidden;
  opacity: 0;
  margin-top: 0;
  transition: max-height 240ms var(--ease), opacity 200ms var(--ease), margin-top 240ms var(--ease);
}

.page-about .duty-card:hover .duty-card__more,
.page-about .duty-card:focus-within .duty-card__more {
  max-height: 220px;
  opacity: 1;
  margin-top: 14px;
}

.page-about .duty-card__more p {
  margin: 0;
  padding-top: 12px;
  border-top: 1px solid var(--line);
  font-size: 13px;
  line-height: 1.7;
  color: var(--slate);
}

@media (min-width: 760px) {
  .page-about .duty-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 22px;
  }
}

/* ---------- 三道手流程 ---------- */

.page-about .flow-list {
  list-style: none;
  margin: 0;
  padding: 0;
  max-width: 44em;
}

.page-about .flow-step {
  display: grid;
  grid-template-columns: 2.6rem minmax(0, 1fr);
  gap: 18px;
  padding: 22px 0;
  border-top: 1px solid rgba(27, 31, 39, 0.16);
}

.page-about .flow-step:last-child {
  border-bottom: 1px solid rgba(27, 31, 39, 0.16);
}

.page-about .flow-step__no {
  font-size: 1.45rem;
  font-weight: 800;
  line-height: 1.25;
  color: var(--agate);
}

.page-about .flow-step__title {
  margin: 0 0 8px;
  font-size: 1.12rem;
  font-weight: 800;
  color: var(--ink);
}

.page-about .flow-step__text {
  margin: 0;
  font-size: 15.5px;
  line-height: 1.82;
  color: rgba(27, 31, 39, 0.78);
}

.page-about .flow-promise {
  margin: 32px 0 0;
  max-width: 44em;
  padding: 18px 20px;
  border-left: 3px solid var(--agate);
  background: rgba(200, 64, 47, 0.06);
  font-size: 15.5px;
  line-height: 1.82;
  color: var(--ink);
}

/* ---------- 时间轴 ---------- */

.page-about .about-tl__media {
  margin: 0 0 42px;
}

.page-about .about-tl {
  list-style: none;
  margin: 0;
  padding: 0;
  max-width: 46em;
}

.page-about .about-tl__item {
  position: relative;
  padding: 0 0 38px 32px;
  border-left: 1px solid var(--line);
}

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

.page-about .about-tl__dot {
  position: absolute;
  left: -4.5px;
  top: 7px;
  width: 8px;
  height: 8px;
  transform: rotate(45deg);
  background: var(--slate);
  transition: background 240ms var(--ease), box-shadow 240ms var(--ease);
}

.page-about .about-tl__item.is-visible .about-tl__dot {
  background: var(--gold);
  box-shadow: 0 0 0 6px rgba(245, 166, 35, 0.14);
}

.page-about .about-tl__year {
  margin: 0 0 8px;
  font-size: 1.35rem;
  font-weight: 800;
  line-height: 1;
  color: var(--paper-white);
}

.page-about .about-tl__item:last-child .about-tl__year {
  color: var(--gold);
}

.page-about .about-tl__title {
  margin: 0 0 8px;
  font-size: 1.12rem;
  font-weight: 800;
  color: var(--paper-white);
}

.page-about .about-tl__text {
  margin: 0;
  max-width: 40em;
  font-size: 15.5px;
  line-height: 1.82;
  color: rgba(247, 243, 234, 0.72);
}

/* ---------- 合作与实训 ---------- */

.page-about .about-coop {
  display: grid;
  gap: 32px;
}

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

.page-about .about-coop__body > p {
  margin: 0 0 22px;
  max-width: var(--about-measure);
  font-size: 17px;
  line-height: 1.85;
}

.page-about .coop-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 22px;
}

.page-about .coop-list__item {
  padding-left: 20px;
  border-left: 2px solid var(--agate);
}

.page-about .coop-list__title {
  margin: 0 0 8px;
  font-size: 1.08rem;
  font-weight: 800;
  color: var(--ink);
}

.page-about .coop-list__text {
  margin: 0;
  font-size: 15.5px;
  line-height: 1.82;
  color: rgba(27, 31, 39, 0.78);
}

@media (min-width: 900px) {
  .page-about .about-coop {
    grid-template-columns: minmax(0, 5fr) minmax(0, 6fr);
    gap: 48px;
    align-items: start;
  }
}

/* ---------- 三件事 ---------- */

.page-about .creed-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 30px;
}

.page-about .creed {
  padding-top: 20px;
  border-top: 1px solid var(--line);
}

.page-about .creed__no {
  display: block;
  margin-bottom: 14px;
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.28em;
  color: var(--gold);
}

.page-about .creed__title {
  margin: 0 0 10px;
  font-size: 1.28rem;
  font-weight: 800;
  color: var(--paper-white);
}

.page-about .creed__text {
  margin: 0;
  font-size: 15.5px;
  line-height: 1.82;
  color: rgba(247, 243, 234, 0.72);
}

@media (min-width: 820px) {
  .page-about .creed-list {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 40px;
  }
}

/* ---------- 后续入口 ---------- */

.page-about .about-next-section {
  padding-block: 56px 72px;
}

.page-about .about-next__heading {
  margin: 0 0 26px;
  font-size: clamp(1.4rem, 3.6vw, 1.9rem);
  font-weight: 800;
  letter-spacing: -0.01em;
  color: var(--paper-white);
}

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

.page-about .about-next__card {
  display: grid;
  gap: 8px;
  padding: 22px 20px;
  border: 1px solid var(--line);
  text-decoration: none;
  color: inherit;
  transition: transform 180ms var(--ease), border-color 180ms var(--ease), background 180ms var(--ease);
}

.page-about .about-next__card:hover,
.page-about .about-next__card:focus-visible {
  transform: translateY(-2px);
  border-color: var(--line-strong);
  background: var(--wash);
}

.page-about .about-next__no {
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.24em;
  color: var(--slate);
}

.page-about .about-next__title {
  font-size: 1.12rem;
  font-weight: 800;
  color: var(--paper-white);
}

.page-about .about-next__desc {
  font-size: 13.5px;
  line-height: 1.7;
  color: var(--slate);
}

@media (min-width: 760px) {
  .page-about .about-next {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 1100px) {
  .page-about .about-next {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

/* ---------- 窄屏兜底 ---------- */

@media (max-width: 479px) {
  .page-about .about-facts {
    grid-template-columns: minmax(0, 1fr);
  }

  .page-about .layer-list__item,
  .page-about .flow-step {
    grid-template-columns: minmax(0, 1fr);
    gap: 8px;
  }
}

.page-about img {
  max-width: 100%;
  height: auto;
}
<<<END>>>