.page-about {
  --about-gutter: clamp(1.25rem, 5vw, 3rem);
  overflow-x: clip;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  background: var(--night);
  color: var(--ivory);
  padding: clamp(5.5rem, 12vw, 8rem) 0 clamp(3rem, 7vw, 5rem);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  left: -20%;
  right: -20%;
  bottom: 0;
  height: 48%;
  background: linear-gradient(102deg, rgba(200, 16, 46, .88), rgba(122, 12, 30, .22) 60%, transparent 92%);
  transform: skewY(-5deg);
  transform-origin: left bottom;
  pointer-events: none;
}

.page-about .about-hero .breadcrumbs ol {
  display: flex;
  flex-wrap: wrap;
  gap: .35rem;
  margin: 0 0 clamp(1.5rem, 4vw, 2.5rem);
  padding: 0;
  list-style: none;
  font-size: .8125rem;
  letter-spacing: .04em;
  color: rgba(246, 241, 231, .6);
}

.page-about .about-hero .breadcrumbs li + li::before {
  content: "/";
  margin-right: .35rem;
  opacity: .55;
}

.page-about .about-hero .breadcrumbs a {
  color: rgba(246, 241, 231, .84);
  text-decoration: none;
  border-bottom: 1px solid rgba(246, 241, 231, .3);
  transition: color .25s var(--ease), border-color .25s var(--ease);
}

.page-about .about-hero .breadcrumbs a:hover,
.page-about .about-hero .breadcrumbs a:focus-visible {
  color: var(--volt);
  border-color: var(--volt);
}

.page-about .about-hero__grid {
  position: relative;
  z-index: 1;
  display: grid;
  gap: 2.5rem;
}

.page-about .about-hero__copy h1 {
  margin: 0 0 1.25rem;
  font-size: clamp(1.95rem, 7vw, 3.6rem);
  line-height: 1.1;
  font-weight: 900;
  letter-spacing: -.012em;
}

.page-about .about-hero__copy h1::after {
  content: "";
  display: block;
  width: 4.5rem;
  height: .5rem;
  margin-top: 1.5rem;
  background: var(--red);
  transform: skewX(-12deg);
}

.page-about .about-hero__copy .lede {
  max-width: 42rem;
  color: rgba(246, 241, 231, .82);
  line-height: 1.85;
}

.page-about .about-hero__actions {
  margin-top: 1.75rem;
}

.page-about .about-hero__visual {
  position: relative;
  margin: 0;
  border-radius: var(--radius-l);
  overflow: hidden;
  border: 1px solid rgba(246, 241, 231, .16);
  box-shadow: var(--shadow-2);
}

.page-about .about-hero__visual img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 9;
  object-fit: cover;
}

.page-about .about-hero__caption {
  position: absolute;
  left: .85rem;
  right: .85rem;
  bottom: .85rem;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: .35rem .75rem;
  padding: .6rem .9rem;
  border-radius: var(--radius-m);
  background: rgba(17, 17, 17, .74);
  border: 1px solid rgba(246, 241, 231, .16);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  font-size: .75rem;
  line-height: 1.5;
  color: rgba(246, 241, 231, .88);
}

.page-about .about-hero__caption .mono {
  color: var(--volt);
  font-size: .75rem;
  letter-spacing: .06em;
}

/* ---------- 通用章节节奏 ---------- */
.page-about .section {
  padding: clamp(3.25rem, 8vw, 6rem) 0;
}

.page-about .prose p {
  margin: 0 0 1rem;
  line-height: 1.85;
}

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

.page-about .about-promise__aside h3 {
  margin: 0 0 1rem;
  font-size: 1.125rem;
}

/* ---------- 01 定位 ---------- */
.page-about .about-position {
  background: var(--ivory);
  color: var(--ink);
}

.page-about .about-position__inner {
  display: grid;
  gap: 2.5rem;
}

.page-about .about-position__lead h2 {
  margin: 0 0 1.25rem;
  font-size: clamp(1.5rem, 5vw, 2.35rem);
  line-height: 1.2;
}

.page-about .about-position__lead .prose {
  color: #3d3f43;
  max-width: 40rem;
}

.page-about .about-position__stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: var(--radius-m);
  overflow: hidden;
}

.page-about .about-stat {
  display: flex;
  flex-direction: column;
  gap: .4rem;
  padding: 1.25rem 1.05rem;
  background: var(--white);
}

.page-about .about-stat .stat__value {
  font-family: var(--font-mono);
  font-size: clamp(1.4rem, 5.4vw, 2rem);
  font-weight: 700;
  line-height: 1;
  color: var(--red);
}

.page-about .about-stat .stat__label {
  font-size: .8125rem;
  line-height: 1.55;
  color: var(--gray);
}

/* ---------- 02 时间线 ---------- */
.page-about .about-timeline {
  position: relative;
  overflow: hidden;
  background: var(--night);
  color: var(--ivory);
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: .35rem;
  background: linear-gradient(90deg, var(--red) 0 38%, var(--volt) 38% 46%, transparent 46% 100%);
}

.page-about .about-timeline .eyebrow {
  color: var(--volt);
}

.page-about .about-timeline .lede {
  color: rgba(246, 241, 231, .78);
}

.page-about .about-axis {
  display: grid;
  gap: 1.15rem;
  margin: 2.5rem 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-axis__item {
  position: relative;
  padding: 1.35rem 1.25rem 1.35rem 1.4rem;
  border-left: 3px solid var(--red);
  border-radius: 0 var(--radius-m) var(--radius-m) 0;
  background: linear-gradient(100deg, rgba(246, 241, 231, .08), rgba(246, 241, 231, .015));
}

.page-about .about-axis__index {
  display: inline-block;
  padding: .12rem .6rem;
  margin-bottom: .7rem;
  border: 1px solid rgba(242, 233, 0, .42);
  border-radius: var(--pill);
  font-size: .7rem;
  letter-spacing: .14em;
  color: var(--volt);
}

.page-about .about-axis__item h3 {
  margin: 0 0 .5rem;
  font-size: 1.125rem;
  color: var(--white);
}

.page-about .about-axis__item p {
  margin: 0;
  font-size: .875rem;
  line-height: 1.8;
  color: rgba(246, 241, 231, .78);
}

/* ---------- 03 资料库 ---------- */
.page-about .about-library {
  background: var(--ivory);
  color: var(--ink);
}

.page-about .about-library__body {
  display: grid;
  gap: 2rem;
  margin-top: 2.5rem;
}

.page-about .about-library__tabs .tab-list {
  display: flex;
  flex-wrap: wrap;
  gap: .5rem;
  margin-bottom: 1.35rem;
}

.page-about .about-library__tabs .tab {
  appearance: none;
  -webkit-appearance: none;
  padding: .5rem 1rem;
  border: 1px solid var(--line-strong);
  border-radius: var(--pill);
  background: transparent;
  color: var(--ink);
  font-family: inherit;
  font-size: .875rem;
  font-weight: 700;
  cursor: pointer;
  transition: background .25s var(--ease), color .25s var(--ease), border-color .25s var(--ease);
}

.page-about .about-library__tabs .tab:hover {
  border-color: var(--red);
  color: var(--red);
}

.page-about .about-library__tabs .tab[aria-selected="true"] {
  background: var(--red);
  border-color: var(--red);
  color: var(--white);
}

.page-about .about-library__tabs .tab:focus-visible {
  outline: 3px solid var(--blue);
  outline-offset: 2px;
}

.page-about .about-library__tabs .tab-panel {
  padding: 1.5rem 1.35rem;
  border: 1px solid var(--line);
  border-radius: var(--radius-m);
  background: var(--white);
  box-shadow: var(--shadow-1);
}

.page-about .about-library__tabs .tab-panel[hidden] {
  display: none;
}

.page-about .about-library__tabs .tab-panel h3 {
  margin: 0 0 .55rem;
  font-size: 1.125rem;
  color: var(--ink);
}

.page-about .about-library__tabs .tab-panel p {
  margin: 0;
  font-size: .9375rem;
  line-height: 1.85;
  color: #3d3f43;
}

.page-about .about-library__media {
  margin: 0;
  border-radius: var(--radius-l);
  overflow: hidden;
  border: 1px solid var(--line);
}

.page-about .about-library__media img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 3 / 2;
  object-fit: cover;
}

/* ---------- 04 团队 ---------- */
.page-about .about-team {
  position: relative;
  overflow: hidden;
  background: var(--red);
  color: var(--white);
}

.page-about .about-team::after {
  content: "";
  position: absolute;
  inset: auto -12% -32% 34%;
  height: 68%;
  background: radial-gradient(circle at 58% 42%, rgba(242, 233, 0, .22), transparent 64%);
  pointer-events: none;
}

.page-about .about-team > .container {
  position: relative;
  z-index: 1;
}

.page-about .about-team .eyebrow {
  color: var(--volt);
}

.page-about .about-team__head h2 {
  margin: 0 0 1rem;
  font-size: clamp(1.5rem, 5.2vw, 2.4rem);
  line-height: 1.2;
  color: var(--white);
}

.page-about .about-team__head .lede {
  max-width: 48rem;
  color: rgba(255, 255, 255, .88);
  line-height: 1.85;
}

.page-about .about-team__groups {
  display: grid;
  gap: 1rem;
  margin-top: 2rem;
}

.page-about .about-team__group {
  padding: 1.35rem 1.25rem;
  border: 1px solid rgba(255, 255, 255, .24);
  border-radius: var(--radius-m);
  background: rgba(17, 17, 17, .22);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
}

.page-about .about-team__group .mono {
  display: inline-block;
  font-size: .72rem;
  letter-spacing: .14em;
  color: var(--volt);
}

.page-about .about-team__group h3 {
  margin: .5rem 0 .55rem;
  font-size: 1.2rem;
  color: var(--white);
}

.page-about .about-team__group p {
  margin: 0;
  font-size: .875rem;
  line-height: 1.8;
  color: rgba(255, 255, 255, .86);
}

.page-about .about-team__media {
  margin: 2.25rem 0 0;
  border-radius: var(--radius-l);
  overflow: hidden;
  border: 1px solid rgba(255, 255, 255, .24);
}

.page-about .about-team__media img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 3 / 2;
  object-fit: cover;
}

/* ---------- 05 合作 ---------- */
.page-about .about-partners {
  background: var(--ink);
  color: var(--ivory);
}

.page-about .about-partners .eyebrow {
  color: var(--volt);
}

.page-about .about-partners .lede {
  max-width: 46rem;
  color: rgba(246, 241, 231, .78);
}

.page-about .about-partners__grid {
  display: grid;
  gap: 1rem;
  margin-top: 2.5rem;
}

.page-about .about-partner {
  padding: 1.35rem 1.25rem;
  border: 1px solid var(--line-dark);
  border-radius: var(--radius-m);
  background: linear-gradient(160deg, rgba(246, 241, 231, .07), rgba(246, 241, 231, .012));
}

.page-about .about-partner__num {
  display: block;
  margin-bottom: .55rem;
  font-family: var(--font-mono);
  font-size: clamp(1.7rem, 6vw, 2.35rem);
  line-height: 1;
  color: var(--volt);
}

.page-about .about-partner__label {
  display: block;
  margin-bottom: .4rem;
  font-size: .9375rem;
  font-weight: 700;
  color: var(--white);
}

.page-about .about-partner p {
  margin: 0;
  font-size: .8125rem;
  line-height: 1.75;
  color: rgba(246, 241, 231, .72);
}

.page-about .about-partners__honor {
  margin: 2rem 0 0;
  padding: 1.1rem 1.35rem;
  border-left: 4px solid var(--blue);
  border-radius: 0 var(--radius-m) var(--radius-m) 0;
  background: rgba(45, 156, 219, .12);
  font-size: .9375rem;
  line-height: 1.75;
  color: rgba(246, 241, 231, .9);
}

/* ---------- 06 承诺 ---------- */
.page-about .about-promise {
  background: var(--ivory);
  color: var(--ink);
}

.page-about .about-promise__inner {
  display: grid;
  gap: 2.25rem;
}

.page-about .about-promise__copy h2 {
  margin: 0 0 1.25rem;
  font-size: clamp(1.5rem, 5vw, 2.35rem);
  line-height: 1.2;
}

.page-about .about-promise__copy .prose {
  max-width: 42rem;
  color: #3d3f43;
}

.page-about .about-promise__actions {
  margin-top: 1.75rem;
}

.page-about .about-promise__aside {
  padding: 1.5rem 1.35rem;
  border: 1px solid var(--line);
  border-radius: var(--radius-l);
  background: var(--white);
  box-shadow: var(--shadow-1);
}

.page-about .about-promise__aside ul {
  display: grid;
  gap: .85rem;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-promise__aside li {
  padding-top: .85rem;
  border-top: 1px solid var(--line);
  font-size: .875rem;
  line-height: 1.7;
  color: #4a4d52;
}

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

.page-about .about-promise__aside a {
  font-weight: 700;
  color: var(--red);
  text-decoration: none;
  border-bottom: 1px solid rgba(200, 16, 46, .35);
  transition: border-color .25s var(--ease);
}

.page-about .about-promise__aside a:hover,
.page-about .about-promise__aside a:focus-visible {
  border-color: var(--red);
}

/* ---------- 自适应 ---------- */
@media (min-width: 600px) {
  .page-about .about-position__stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

@media (min-width: 780px) {
  .page-about .about-axis {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 1.5rem;
  }

  .page-about .about-team__groups {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 1.25rem;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 1fr);
    align-items: center;
    gap: 3.5rem;
  }

  .page-about .about-position__inner {
    grid-template-columns: minmax(0, 1.45fr) minmax(260px, .85fr);
    align-items: start;
    gap: 3.5rem;
  }

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

@media (min-width: 960px) {
  .page-about .about-library__body {
    grid-template-columns: minmax(0, 1.3fr) minmax(0, 1fr);
    align-items: start;
    gap: 3rem;
  }

  .page-about .about-partners__grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 1.25rem;
  }

  .page-about .about-promise__inner {
    grid-template-columns: minmax(0, 1.4fr) minmax(270px, .8fr);
    align-items: start;
    gap: 3.5rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-hero::before {
    transform: none;
  }
}