.page-about {
  --about-teal-ink: #1B8378;
  --about-rail-w: 212px;
  background: var(--sk-deep);
  overflow-x: clip;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding: calc(var(--sk-header-h) + clamp(20px, 4.5vw, 52px)) 0 clamp(36px, 6vw, 76px);
  background:
    radial-gradient(90% 70% at 6% 0%, rgba(46, 196, 182, .18), transparent 62%),
    radial-gradient(70% 60% at 100% 8%, rgba(255, 107, 74, .13), transparent 60%),
    linear-gradient(180deg, #0B1F3A 0%, #0d2749 100%);
  color: var(--sk-paper);
}

.page-about .about-hero__grid {
  display: grid;
  gap: clamp(28px, 5vw, 56px);
  margin-top: clamp(18px, 3.5vw, 38px);
  align-items: center;
}

.page-about .about-hero__title {
  margin: 14px 0 0;
  font-size: clamp(29px, 6.2vw, 60px);
  line-height: 1.06;
  letter-spacing: -.012em;
  color: var(--sk-paper);
}

.page-about .about-hero__intro {
  max-width: 56ch;
  margin: 20px 0 0;
  font-size: clamp(15px, 1.6vw, 17px);
  line-height: 1.8;
  color: var(--sk-mist);
}

.page-about .about-hero__facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: clamp(24px, 4vw, 42px) 0 0;
  background: var(--sk-line);
  border: 1px solid var(--sk-line);
}

.page-about .about-hero__fact {
  padding: 15px 14px;
  background: #0d2444;
}

.page-about .about-hero__fact dt {
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--sk-mist);
}

.page-about .about-hero__fact dd {
  margin: 8px 0 0;
  font-size: 14px;
  color: var(--sk-paper);
}

.page-about .about-hero__num {
  margin-right: 5px;
  font-family: var(--sk-font-mono);
  font-size: 21px;
  color: var(--sk-teal);
}

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

.page-about .about-hero__figure .sk-figure__frame {
  padding: 10px;
  border: 1px solid var(--sk-line);
  background: linear-gradient(155deg, rgba(46, 196, 182, .16), rgba(11, 31, 58, .3) 48%, rgba(255, 107, 74, .14));
}

.page-about .about-hero__figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 20px), calc(100% - 20px) 100%, 0 100%);
}

.page-about .about-hero__figure .sk-figure__cap {
  margin-top: 12px;
}

/* ---------- 档案主体 ---------- */
.page-about .about-archive {
  padding: clamp(36px, 6vw, 84px) 0 clamp(48px, 8vw, 110px);
  background: var(--sk-paper);
  color: var(--sk-ink);
}

.page-about .about-archive__inner {
  display: grid;
  gap: clamp(28px, 5vw, 48px);
}

.page-about .about-rail__title {
  margin: 0 0 12px;
  font-size: 12px;
  letter-spacing: .18em;
  color: #6b7f95;
}

.page-about .about-rail__list {
  display: flex;
  gap: 8px;
  margin: 0;
  padding: 0 0 8px;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: thin;
}

.page-about .about-rail__list li {
  flex: none;
}

.page-about .about-rail__list .sk-index__link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  white-space: nowrap;
}

.page-about .about-rail__list .sk-index__link[aria-current] {
  color: var(--sk-coral);
}

.page-about .about-rail__meta {
  margin: 16px 0 0;
  font-size: 12px;
  letter-spacing: .1em;
  color: #6b7f95;
}

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

.page-about .about-block + .about-block {
  margin-top: clamp(44px, 7vw, 92px);
}

.page-about .about-block__head {
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding-bottom: 14px;
  margin-bottom: clamp(18px, 3vw, 28px);
  border-bottom: 1px solid rgba(62, 90, 117, .35);
}

.page-about .about-block__num {
  flex: none;
  font-size: 13px;
  letter-spacing: .16em;
  color: var(--sk-coral);
}

.page-about .about-block__head h2 {
  margin: 0;
}

.page-about .about-flow .sk-prose {
  max-width: 68ch;
}

/* 旁注 */
.page-about .about-note {
  margin-top: clamp(20px, 3vw, 30px);
  padding: 16px 18px 18px;
  border-left: 3px solid var(--sk-teal);
  background: linear-gradient(90deg, rgba(46, 196, 182, .13), rgba(46, 196, 182, 0) 84%);
}

.page-about .about-note__title {
  margin: 0 0 10px;
  font-size: 13px;
  letter-spacing: .12em;
  color: #3a4d61;
}

.page-about .about-note__list {
  display: grid;
  gap: 9px;
  margin: 0;
  padding: 0;
  list-style: none;
  font-size: 14.5px;
  line-height: 1.7;
  color: #33404f;
}

.page-about .about-note__list li {
  display: flex;
  gap: 12px;
  align-items: baseline;
}

.page-about .about-note__list .sk-mono {
  flex: none;
  min-width: 44px;
  font-size: 12px;
  letter-spacing: .06em;
  color: var(--about-teal-ink);
}

/* 斜线分隔 */
.page-about .about-slashes {
  height: 12px;
  margin: clamp(34px, 6vw, 72px) 0;
  background: repeating-linear-gradient(118deg, rgba(62, 90, 117, .5) 0 1px, transparent 1px 9px);
  -webkit-mask-image: linear-gradient(90deg, transparent, #000 12%, #000 88%, transparent);
  mask-image: linear-gradient(90deg, transparent, #000 12%, #000 88%, transparent);
}

/* 时间线图 */
.page-about .about-timeline-figure {
  margin: clamp(22px, 4vw, 34px) 0 0;
}

.page-about .about-timeline-figure .sk-figure__frame {
  padding: 10px;
  background: #fff;
  border: 1px solid rgba(62, 90, 117, .35);
}

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

/* 阶段卡片 */
.page-about .about-stages {
  display: grid;
  gap: 14px;
  margin-top: clamp(20px, 3vw, 32px);
}

.page-about .about-stage {
  position: relative;
  padding: 22px 18px 18px;
  background: #fff;
  border: 1px solid rgba(62, 90, 117, .3);
  transition: transform .24s var(--sk-ease), border-color .24s var(--sk-ease), box-shadow .24s var(--sk-ease);
}

.page-about .about-stage::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 3px;
  background: var(--sk-amber);
}

.page-about .about-stage--current::before {
  background: var(--sk-coral);
}

.page-about .about-stage:hover,
.page-about .about-stage:focus {
  transform: translateY(-2px);
  border-color: var(--sk-line);
  box-shadow: 0 12px 26px -20px rgba(11, 31, 58, .8);
  outline: none;
}

.page-about .about-stage__num {
  margin: 0;
  font-size: 12px;
  letter-spacing: .12em;
  color: #6b7f95;
}

.page-about .about-stage .sk-h3 {
  margin: 8px 0 6px;
  font-size: 17px;
}

.page-about .about-stage__line {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.7;
  color: #33404f;
}

.page-about .about-stage__more {
  max-height: 0;
  margin: 0;
  overflow: hidden;
  opacity: 0;
  font-size: 13.5px;
  line-height: 1.7;
  color: #5a6b7d;
  transition: max-height .28s var(--sk-ease), opacity .28s var(--sk-ease), margin-top .28s var(--sk-ease);
}

.page-about .about-stage:hover .about-stage__more,
.page-about .about-stage:focus .about-stage__more,
.page-about .about-stage:focus-within .about-stage__more {
  max-height: 240px;
  margin-top: 10px;
  opacity: 1;
}

/* 团队 */
.page-about .about-team {
  display: grid;
  gap: clamp(22px, 3vw, 32px);
}

.page-about .about-team .sk-figure {
  margin: 0;
}

.page-about .about-team__figure .sk-figure__frame {
  padding: 10px;
  background: #fff;
  border: 1px solid rgba(62, 90, 117, .35);
}

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

.page-about .about-roles {
  display: grid;
  gap: 1px;
  margin: clamp(24px, 3vw, 34px) 0 0;
  padding: 0;
  list-style: none;
  background: rgba(62, 90, 117, .28);
  border: 1px solid rgba(62, 90, 117, .28);
}

.page-about .about-roles__item {
  padding: 18px 16px;
  background: var(--sk-paper);
}

.page-about .about-roles__item .sk-h3 {
  margin: 0 0 6px;
  font-size: 15px;
  color: var(--sk-deep);
}

.page-about .about-roles__item p {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: #45566a;
}

/* 表格 */
.page-about .about-table-wrap {
  margin-top: clamp(22px, 3vw, 32px);
  border: 1px solid rgba(62, 90, 117, .3);
  overflow-x: auto;
}

.page-about .about-table-wrap .sk-table {
  width: 100%;
  min-width: 620px;
}

/* 协作链接 */
.page-about .about-eco__links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px 24px;
  margin-top: clamp(22px, 3vw, 30px);
  padding-top: 18px;
  border-top: 1px solid rgba(62, 90, 117, .3);
  font-size: 14.5px;
}

.page-about .about-eco__links a {
  padding-bottom: 2px;
  color: var(--sk-deep);
  text-decoration: none;
  border-bottom: 1px solid var(--sk-coral);
  transition: color .2s var(--sk-ease);
}

.page-about .about-eco__links a:hover {
  color: var(--sk-coral);
}

/* 引用块 */
.page-about .about-quote {
  position: relative;
  margin: clamp(30px, 5vw, 56px) 0 0;
  padding: clamp(24px, 3.4vw, 40px);
  background: linear-gradient(135deg, #0B1F3A 0%, #16304F 100%);
  color: var(--sk-paper);
  clip-path: polygon(0 0, calc(100% - 24px) 0, 100% 24px, 100% 100%, 0 100%);
}

.page-about .about-quote::before {
  content: "";
  position: absolute;
  inset: 0 auto 0 0;
  width: 4px;
  background: var(--sk-coral);
}

.page-about .about-quote p {
  margin: 0;
  font-size: clamp(17px, 2.2vw, 24px);
  line-height: 1.6;
  font-weight: 500;
}

.page-about .about-quote cite {
  display: block;
  margin-top: 14px;
  font-style: normal;
  font-size: 12px;
  letter-spacing: .14em;
  color: var(--sk-teal);
}

/* ---------- 收尾 ---------- */
.page-about .about-outro {
  padding: clamp(44px, 6vw, 84px) 0 clamp(48px, 7vw, 92px);
  background:
    radial-gradient(80% 100% at 100% 0%, rgba(255, 107, 74, .15), transparent 62%),
    linear-gradient(180deg, #0B1F3A 0%, #10294a 100%);
  color: var(--sk-paper);
}

.page-about .about-outro__title {
  max-width: 26ch;
  margin: 12px 0 0;
  font-size: clamp(22px, 3.4vw, 36px);
  line-height: 1.25;
}

.page-about .about-outro__text {
  max-width: 54ch;
  margin: 16px 0 0;
  font-size: 15.5px;
  line-height: 1.8;
  color: var(--sk-mist);
}

.page-about .about-outro__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: clamp(24px, 3vw, 34px);
}

/* ---------- 响应式 ---------- */
@media (min-width: 720px) {
  .page-about .about-hero__facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

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

@media (min-width: 1000px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.06fr) minmax(0, .94fr);
    align-items: end;
  }

  .page-about .about-archive__inner {
    grid-template-columns: minmax(0, var(--about-rail-w)) minmax(0, 1fr);
    gap: clamp(36px, 5vw, 80px);
    align-items: start;
  }

  .page-about .about-rail__inner {
    position: sticky;
    top: calc(var(--sk-header-h) + 28px);
    padding-right: 20px;
    border-right: 1px solid rgba(62, 90, 117, .3);
  }

  .page-about .about-rail__list {
    display: block;
    padding: 0;
    overflow: visible;
  }

  .page-about .about-rail__list li {
    flex: none;
  }

  .page-about .about-rail__list li + li {
    margin-top: 5px;
  }

  .page-about .about-rail__list .sk-index__link {
    display: flex;
    white-space: normal;
  }

  .page-about .about-team {
    grid-template-columns: minmax(0, 1.08fr) minmax(0, .92fr);
    gap: clamp(28px, 4vw, 48px);
    align-items: start;
  }
}

@media (min-width: 1240px) {
  .page-about .about-stages {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

@media (hover: none) {
  .page-about .about-stage__more {
    max-height: 240px;
    margin-top: 10px;
    opacity: 1;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-stage,
  .page-about .about-stage__more,
  .page-about .about-eco__links a {
    transition: none;
  }

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