.page-about {
  --about-rail-w: 228px;
  background: var(--yh-ink);
  color: var(--yh-paper);
}

/* ---------- 面包屑 ---------- */
.page-about .about-crumb {
  padding-block: 13px;
  background: var(--yh-ink-3);
  border-bottom: 1px solid var(--yh-rule);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  isolation: isolate;
  overflow: hidden;
  padding-block: clamp(30px, 5vw, 62px) clamp(26px, 4vw, 44px);
  background:
    radial-gradient(140% 100% at 88% -20%, rgba(226, 118, 47, .26), transparent 58%),
    radial-gradient(92% 82% at -10% 0%, rgba(127, 200, 212, .16), transparent 55%),
    var(--yh-ink);
  border-bottom: 1px solid var(--yh-rule);
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background-image:
    repeating-linear-gradient(90deg, rgba(244, 235, 216, .05) 0 1px, transparent 1px 88px),
    repeating-linear-gradient(0deg, rgba(244, 235, 216, .035) 0 1px, transparent 1px 88px);
}

.page-about .about-hero__eyebrow {
  color: var(--yh-ice);
  letter-spacing: .14em;
}

.page-about .about-hero__title {
  margin: 14px 0 0;
  max-width: 17ch;
  font-family: var(--yh-font-display);
  font-size: clamp(30px, 6.4vw, 68px);
  line-height: 1.06;
  letter-spacing: -.02em;
  color: var(--yh-paper);
  overflow-wrap: break-word;
}

.page-about .about-hero__lede {
  margin: 20px 0 0;
  max-width: 40em;
  font-family: var(--yh-font-editorial);
  font-size: clamp(15px, 1.6vw, 18px);
  line-height: 1.85;
  color: rgba(244, 235, 216, .8);
}

/* ---------- 首屏数据条 ---------- */
.page-about .about-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 30px 0 0;
  padding: 1px;
  background: var(--yh-rule);
  border: 1px solid var(--yh-rule);
}

.page-about .about-stats__cell {
  background: var(--yh-ink);
  padding: 14px 16px;
}

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

.page-about .about-stats__v {
  margin: 8px 0 0;
  display: flex;
  align-items: baseline;
  gap: 5px;
  font-family: var(--yh-font-num);
  font-variant-numeric: tabular-nums;
  font-size: clamp(22px, 3vw, 30px);
  line-height: 1;
  color: var(--yh-gold);
}

.page-about .about-stats__u {
  font-family: var(--yh-font-body);
  font-size: 12px;
  color: var(--yh-mist);
  letter-spacing: .04em;
}

/* ---------- 主体骨架 ---------- */
.page-about .about-shell {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 0;
  padding-bottom: clamp(24px, 4vw, 48px);
}

/* ---------- 章节导航（移动端横向条） ---------- */
.page-about .about-rail {
  position: sticky;
  top: var(--yh-hh);
  z-index: 6;
  margin-inline: calc(var(--yh-gutter) * -1);
  padding: 9px var(--yh-gutter);
  overflow-x: auto;
  background: rgba(11, 16, 32, .94);
  border-bottom: 1px solid var(--yh-rule);
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
  scrollbar-width: none;
}

.page-about .about-rail::-webkit-scrollbar {
  display: none;
}

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

.page-about .about-rail__list {
  display: flex;
  gap: 20px;
  margin: 0;
  padding: 0;
  list-style: none;
  white-space: nowrap;
}

.page-about .about-rail__item {
  flex: none;
}

.page-about .about-rail .about-rail__link {
  display: inline-flex;
  align-items: baseline;
  gap: 7px;
  padding: 5px 0;
  font-size: 13px;
  line-height: 1.2;
  color: var(--yh-mist);
  text-decoration: none;
  transition: color .18s var(--yh-ease);
}

.page-about .about-rail .about-rail__link:hover {
  color: var(--yh-paper);
}

.page-about .about-rail .about-rail__link[aria-current="true"] {
  color: var(--yh-gold);
}

.page-about .about-rail__num {
  font-size: 11px;
  letter-spacing: .06em;
  color: var(--yh-ice);
}

.page-about .about-rail .about-rail__link[aria-current="true"] .about-rail__num {
  color: var(--yh-orange);
}

/* ---------- 章节通用 ---------- */
.page-about .about-body {
  min-width: 0;
}

.page-about .about-sec {
  padding-block: clamp(34px, 5vw, 64px);
  border-bottom: 1px solid var(--yh-rule);
}

.page-about .about-sec:first-child {
  border-top: 0;
}

.page-about .about-sec__head {
  display: flex;
  align-items: baseline;
  gap: 14px;
  margin-bottom: 16px;
}

.page-about .about-sec__num {
  flex: none;
  font-size: clamp(20px, 2.4vw, 26px);
  line-height: 1;
  color: var(--yh-gold);
  letter-spacing: -.02em;
}

.page-about .about-sec__title {
  margin: 0;
  color: var(--yh-paper);
  font-family: var(--yh-font-display);
  line-height: 1.18;
  letter-spacing: -.02em;
  overflow-wrap: break-word;
}

.page-about .about-sec__intro {
  margin: 0 0 20px;
  max-width: 38em;
  font-size: 16px;
  line-height: 1.85;
  color: rgba(244, 235, 216, .78);
}

.page-about .about-body p {
  color: rgba(244, 235, 216, .76);
  line-height: 1.85;
}

.page-about .about-body a {
  color: var(--yh-ice);
  text-decoration: none;
  border-bottom: 1px solid rgba(127, 200, 212, .4);
  transition: color .18s var(--yh-ease), border-color .18s var(--yh-ease);
}

.page-about .about-body a:hover {
  color: var(--yh-gold);
  border-color: var(--yh-gold);
}

.page-about .about-h3,
.page-about .about-tl__h,
.page-about .about-role__h,
.page-about .about-flow__h,
.page-about .about-dist__h,
.page-about .about-ver__h {
  margin: 0 0 8px;
  color: var(--yh-paper);
  font-family: var(--yh-font-display);
  line-height: 1.3;
  letter-spacing: -.01em;
}

/* ---------- 图 ---------- */
.page-about .about-figure {
  margin: 22px 0 26px;
  overflow: hidden;
  border: 1px solid var(--yh-rule);
  background: var(--yh-ink-2);
}

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

.page-about .about-figure figcaption {
  padding: 10px 14px;
  border-top: 1px solid var(--yh-rule);
  font-family: var(--yh-font-editorial);
  font-size: 12px;
  line-height: 1.7;
  color: var(--yh-mist);
}

/* ---------- 时间线 ---------- */
.page-about .about-tl {
  position: relative;
}

.page-about .about-tl__track {
  position: relative;
  height: 26px;
  margin-bottom: 10px;
}

.page-about .about-tl__track svg {
  display: block;
  width: 100%;
  height: 26px;
  overflow: visible;
}

.page-about .about-tl__track path {
  fill: none;
  stroke: var(--yh-rule);
  stroke-width: 1.5;
}

.page-about .about-tl__track circle {
  fill: var(--yh-gold);
}

.page-about .about-tl__list {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-tl__item {
  position: relative;
  padding: 20px 18px 20px;
  background: var(--yh-ink-2);
  border: 1px solid var(--yh-rule);
  border-top: 2px solid var(--yh-orange);
  transition:
    transform .18s var(--yh-ease),
    border-color .18s var(--yh-ease);
}

.page-about .about-tl__item:hover,
.page-about .about-tl__item:focus-visible {
  transform: translateY(-4px);
  border-color: var(--yh-gold);
  outline: none;
}

.page-about .about-tl__item:focus-visible {
  outline: 2px solid var(--yh-gold);
  outline-offset: 2px;
}

.page-about .about-tl__tag {
  margin: 0 0 10px;
  font-size: 11px;
  letter-spacing: .14em;
  color: var(--yh-ice);
}

.page-about .about-tl__item p {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
}

.page-about .about-tl__meta {
  margin-top: 14px !important;
  padding-top: 12px;
  border-top: 1px dashed var(--yh-rule);
  font-family: var(--yh-font-num);
  font-variant-numeric: tabular-nums;
  font-size: 12px !important;
  letter-spacing: .04em;
  color: var(--yh-gold) !important;
}

/* ---------- 团队两栏 ---------- */
.page-about .about-split {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 24px;
}

.page-about .about-roles {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  margin: 22px 0 0;
  padding: 1px;
  list-style: none;
  background: var(--yh-rule);
  border: 1px solid var(--yh-rule);
}

.page-about .about-role {
  display: grid;
  grid-template-columns: 46px minmax(0, 1fr);
  gap: 14px;
  padding: 16px 16px 18px;
  background: var(--yh-ink);
}

.page-about .about-role__num {
  font-size: 26px;
  line-height: 1;
  color: var(--yh-gold);
  letter-spacing: -.03em;
}

.page-about .about-role p {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
}

.page-about .about-teamfig {
  margin: 0;
  border: 1px solid var(--yh-rule);
  background: var(--yh-ink-2);
  overflow: hidden;
}

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

/* ---------- 暖纸色引言 ---------- */
.page-about .about-quote {
  margin: clamp(26px, 4vw, 46px) 0;
  padding: clamp(20px, 3.6vw, 34px);
  max-width: 48ch;
  background: var(--yh-paper);
  border-left: 6px solid var(--yh-orange);
  color: var(--yh-ink);
}

.page-about .about-quote p {
  margin: 0;
  font-family: var(--yh-font-editorial);
  font-size: clamp(17px, 2.3vw, 23px);
  line-height: 1.65;
  color: var(--yh-ink);
}

/* ---------- 流程 ---------- */
.page-about .about-flow {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  margin: 24px 0 0;
  padding: 1px;
  list-style: none;
  background: var(--yh-rule);
  border: 1px solid var(--yh-rule);
}

.page-about .about-flow__step {
  padding: 18px 16px 20px;
  background: var(--yh-ink);
}

.page-about .about-flow__num {
  display: inline-block;
  margin-bottom: 10px;
  padding: 2px 8px;
  border: 1px solid var(--yh-gold);
  font-size: 11px;
  letter-spacing: .1em;
  color: var(--yh-gold);
}

.page-about .about-flow__step p {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
}

.page-about .about-flow__note {
  margin: 18px 0 0;
  max-width: 40em;
  font-size: 14px;
  line-height: 1.85;
  color: rgba(244, 235, 216, .7);
}

/* ---------- 分布 ---------- */
.page-about .about-dist {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 26px;
  margin-top: 8px;
}

.page-about .about-meter {
  margin-bottom: 18px;
}

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

.page-about .about-meter__top {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 8px;
}

.page-about .about-meter__k {
  font-size: 13px;
  line-height: 1.5;
  color: rgba(244, 235, 216, .72);
}

.page-about .about-meter__v {
  flex: none;
  font-size: 20px;
  line-height: 1;
  color: var(--yh-gold);
  letter-spacing: -.02em;
}

.page-about .about-meter__bar {
  height: 6px;
  overflow: hidden;
  background: var(--yh-rule);
}

.page-about .about-meter__fill {
  display: block;
  height: 100%;
  background: linear-gradient(90deg, var(--yh-orange), var(--yh-gold));
}

.page-about .about-meter__fill--63 { width: 63%; }
.page-about .about-meter__fill--78 { width: 78%; }
.page-about .about-meter__fill--21 { width: 21%; }

.page-about .about-dist__text h3 {
  margin-bottom: 10px;
}

.page-about .about-dist__text p {
  margin: 0 0 14px;
  font-size: 14.5px;
  line-height: 1.85;
}

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

/* ---------- 版本对照 ---------- */
.page-about .about-ver {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
  margin-top: 22px;
}

.page-about .about-ver__col {
  padding: 20px 18px 22px;
  background: var(--yh-ink-2);
  border: 1px solid var(--yh-rule);
}

.page-about .about-ver__col--new {
  border-color: rgba(217, 164, 65, .7);
  background:
    linear-gradient(160deg, rgba(217, 164, 65, .1), transparent 62%),
    var(--yh-ink-2);
}

.page-about .about-ver__tag {
  margin: 0 0 12px;
  font-size: 22px;
  line-height: 1;
  letter-spacing: -.02em;
  color: var(--yh-gold);
}

.page-about .about-ver__col p {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
}

.page-about .about-ver__note {
  margin: 20px 0 0;
  max-width: 42em;
  font-size: 14px;
  line-height: 1.85;
  color: rgba(244, 235, 216, .72);
}

/* ---------- 收尾 ---------- */
.page-about .about-next {
  margin-top: clamp(32px, 5vw, 56px);
  padding-block: clamp(30px, 4.6vw, 50px);
  border-top: 1px solid var(--yh-rule);
  background:
    linear-gradient(118deg, rgba(226, 118, 47, .18), rgba(127, 200, 212, .1) 70%, transparent),
    var(--yh-ink-3);
}

.page-about .about-next__h {
  margin: 0 0 10px;
  color: var(--yh-paper);
  font-family: var(--yh-font-display);
  letter-spacing: -.02em;
}

.page-about .about-next__lede {
  margin: 0 0 22px;
  max-width: 34em;
  font-size: 15px;
  line-height: 1.8;
  color: rgba(244, 235, 216, .76);
}

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

.page-about .about-next__links .yh-btn {
  text-decoration: none;
}

/* ---------- 窄屏兜底 ---------- */
@media (max-width: 459px) {
  .page-about .about-stats__v {
    font-size: 22px;
  }

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

  .page-about .about-role__num {
    font-size: 22px;
  }
}

/* ---------- 平板 / 桌面 ---------- */
@media (min-width: 700px) {
  .page-about .about-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

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

  .page-about .about-tl__list {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 18px;
  }
}

@media (min-width: 900px) {
  .page-about .about-dist {
    grid-template-columns: minmax(0, .9fr) minmax(0, 1.1fr);
    gap: 40px;
    align-items: start;
  }

  .page-about .about-split {
    grid-template-columns: minmax(0, 1.4fr) minmax(0, .72fr);
    gap: 32px;
    align-items: start;
  }
}

@media (min-width: 1024px) {
  .page-about .about-shell {
    grid-template-columns: var(--about-rail-w) minmax(0, 1fr);
    column-gap: clamp(28px, 3.4vw, 56px);
  }

  .page-about .about-rail {
    position: sticky;
    top: calc(var(--yh-hh) + 26px);
    grid-column: 1;
    align-self: start;
    margin-inline: 0;
    padding: 0;
    overflow: visible;
    background: none;
    border-bottom: 0;
    -webkit-backdrop-filter: none;
    backdrop-filter: none;
  }

  .page-about .about-rail__inner {
    position: relative;
    padding-left: 18px;
  }

  .page-about .about-rail__inner::before {
    content: "";
    position: absolute;
    left: 0;
    top: 2px;
    bottom: 2px;
    width: 1px;
    background-image: repeating-linear-gradient(180deg, var(--yh-rule) 0 1px, transparent 1px 12px);
  }

  .page-about .about-rail__label {
    display: block;
    margin: 0 0 12px;
    color: var(--yh-mist);
    letter-spacing: .18em;
  }

  .page-about .about-rail__list {
    display: block;
    white-space: normal;
  }

  .page-about .about-rail__item {
    margin-bottom: 6px;
  }

  .page-about .about-rail .about-rail__link {
    display: flex;
    align-items: baseline;
    gap: 10px;
    padding: 8px 0 8px 2px;
    font-size: 13px;
    line-height: 1.5;
  }

  .page-about .about-rail__txt {
    display: block;
  }

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

  .page-about .about-sec__head {
    gap: 18px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-tl__item,
  .page-about .about-body a,
  .page-about .about-rail .about-rail__link {
    transition: none;
  }

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