.page-about {
  --about-rail: 206px;
  --about-hair: rgba(30, 58, 86, 0.75);
  --about-body: rgba(232, 237, 242, 0.86);
  position: relative;
  background: var(--ink-900);
  color: var(--mist);
  overflow-x: hidden;
}

/* ---------- 面包屑 ---------- */
.page-about .about-crumb {
  padding-top: clamp(16px, 3vw, 28px);
  font-family: var(--font-mono);
  font-size: 0.76rem;
  letter-spacing: 0.04em;
  color: var(--fog);
}
.page-about .about-crumb a {
  color: var(--fog);
  text-decoration: none;
}
.page-about .about-crumb a:hover {
  color: var(--cyan-pulse);
}
.page-about .about-crumb [aria-current="page"] {
  color: var(--mist);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  isolation: isolate;
  padding: clamp(28px, 5vw, 64px) 0 clamp(30px, 4vw, 52px);
}
.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: -40px 0 0;
  z-index: -1;
  background-image:
    linear-gradient(var(--about-hair) 1px, transparent 1px),
    linear-gradient(90deg, var(--about-hair) 1px, transparent 1px);
  background-size: 120px 120px;
  transform: skewY(-6deg);
  transform-origin: left top;
  opacity: 0.3;
  mask-image: linear-gradient(to bottom, #000 0%, transparent 88%);
  -webkit-mask-image: linear-gradient(to bottom, #000 0%, transparent 88%);
  pointer-events: none;
}
.page-about .about-hero__title {
  margin: 0.28em 0 0.5em;
  max-width: 16ch;
  font-size: clamp(2.2rem, 7.6vw, 5.1rem);
  line-height: 0.96;
  letter-spacing: -0.025em;
  color: var(--mist);
}
.page-about .about-hero__lede {
  max-width: 48ch;
  color: var(--about-body);
}

.page-about .about-hero__stats {
  display: flex;
  flex-wrap: wrap;
  gap: clamp(20px, 4vw, 56px);
  margin: clamp(28px, 4vw, 46px) 0 0;
  padding-top: 18px;
  border-top: 1px solid var(--about-hair);
}
.page-about .about-stat {
  min-width: 120px;
}
.page-about .about-stat dt {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.08em;
  color: var(--fog);
}
.page-about .about-stat dd {
  margin: 6px 0 0;
  font-family: var(--font-display);
  font-size: clamp(1.5rem, 3.6vw, 2.3rem);
  line-height: 1;
  color: var(--mist);
}
.page-about .about-stat__num {
  color: var(--orange-signal);
  margin-right: 2px;
}
.page-about .about-stat:nth-child(2) .about-stat__num {
  color: var(--cyan-pulse);
}

/* ---------- 主体骨架 ---------- */
.page-about .about-shell {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(20px, 3vw, 34px);
  padding-top: clamp(24px, 4vw, 56px);
  padding-bottom: clamp(48px, 7vw, 110px);
}
@media (min-width: 960px) {
  .page-about .about-shell {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    gap: clamp(36px, 5vw, 84px);
  }
}

/* ---------- 章节索引 ---------- */
.page-about .about-toc {
  align-self: start;
  padding: 12px 0 0;
  border-top: 1px solid var(--about-hair);
}
.page-about .about-toc__label {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.16em;
  color: var(--fog);
}
.page-about .about-toc__list {
  display: flex;
  gap: 6px 18px;
  margin: 0;
  padding: 0 0 8px;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: none;
}
.page-about .about-toc__list::-webkit-scrollbar {
  display: none;
}
.page-about .about-toc__list a {
  display: block;
  padding: 4px 0;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.02em;
  white-space: nowrap;
  color: var(--fog);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color 160ms var(--fh-ease), border-color 160ms var(--fh-ease);
}
.page-about .about-toc__list a:hover,
.page-about .about-toc__list a.is-active {
  color: var(--cyan-pulse);
  border-bottom-color: var(--cyan-pulse);
}
@media (min-width: 960px) {
  .page-about .about-toc {
    position: sticky;
    top: 108px;
    padding: 0 0 0 16px;
    border-top: 0;
    border-left: 2px solid var(--ink-500);
  }
  .page-about .about-toc__list {
    display: block;
    overflow: visible;
    padding: 0;
  }
  .page-about .about-toc__list li + li {
    margin-top: 2px;
  }
}

/* ---------- 章节通用 ---------- */
.page-about .about-sec {
  padding: clamp(34px, 5vw, 62px) 0;
  border-top: 1px solid var(--about-hair);
}
.page-about .about-sec:first-child {
  border-top: 0;
  padding-top: 0;
}
.page-about .about-sec__title {
  margin: 0.34em 0 0.62em;
  max-width: 24ch;
  font-size: clamp(1.65rem, 4.2vw, 2.85rem);
  line-height: 1.04;
  letter-spacing: -0.018em;
  color: var(--mist);
}
.page-about .about-sec__lede {
  max-width: 46ch;
  margin: 0 0 1.4em;
  color: var(--about-body);
}
.page-about .about-sec__prose {
  max-width: 62ch;
  color: var(--about-body);
  font-size: 1.01rem;
  line-height: 1.85;
}
.page-about .about-sec__prose p {
  margin: 0 0 1.1em;
}
.page-about .about-sec__prose p:last-child {
  margin-bottom: 0;
}

/* ---------- 宽窄交替分栏 ---------- */
.page-about .about-split {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(22px, 4vw, 42px);
  align-items: start;
}
@media (min-width: 860px) {
  .page-about .about-split {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
  }
  .page-about .about-split--flip {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
  }
  .page-about .about-split--wide {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
  }
}

/* ---------- 缘起图 ---------- */
.page-about .about-origin__fig {
  margin: 0;
}
.page-about .about-origin__fig .fh-figure__media {
  aspect-ratio: 4 / 3;
}

/* ---------- 主张卡片 ---------- */
.page-about .about-claims {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
  margin: 0;
  padding: 0;
  list-style: none;
}
.page-about .about-claim {
  position: relative;
  padding: 24px 20px 20px;
  background: var(--ink-700);
  border: 1px solid var(--ink-500);
  transition: border-color 180ms var(--fh-ease), transform 180ms var(--fh-ease);
}
.page-about .about-claim::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  width: 36px;
  height: 3px;
  background: var(--cyan-pulse);
}
.page-about .about-claim:hover {
  border-color: var(--cyan-pulse);
  transform: translateY(-4px);
}
.page-about .about-claim__no {
  display: block;
  margin-bottom: 10px;
  font-size: 0.74rem;
  letter-spacing: 0.14em;
  color: var(--orange-signal);
}
.page-about .about-claim__name {
  margin: 0 0 10px;
  font-family: var(--font-display);
  font-size: 1.32rem;
  line-height: 1.15;
  letter-spacing: -0.01em;
  color: var(--mist);
}
.page-about .about-claim__text {
  margin: 0;
  font-size: 0.95rem;
  line-height: 1.75;
  color: var(--about-body);
}
.page-about .about-claim__more {
  margin: 10px 0 0;
  padding-top: 10px;
  border-top: 1px dashed rgba(30, 58, 86, 0.95);
  font-size: 0.84rem;
  line-height: 1.7;
  color: var(--fog);
}
@media (min-width: 720px) {
  .page-about .about-claims {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 18px;
  }
  .page-about .about-claim:nth-child(2) {
    margin-top: 28px;
  }
  .page-about .about-claim:nth-child(3) {
    margin-top: 56px;
  }
}
@media (hover: hover) and (min-width: 720px) {
  .page-about .about-claim__more {
    max-height: 0;
    margin-top: 0;
    padding-top: 0;
    border-top-color: transparent;
    overflow: hidden;
    opacity: 0;
    transition: max-height 240ms var(--fh-ease), opacity 200ms var(--fh-ease),
      margin-top 200ms var(--fh-ease), padding-top 200ms var(--fh-ease);
  }
  .page-about .about-claim:hover .about-claim__more {
    max-height: 9rem;
    margin-top: 10px;
    padding-top: 10px;
    border-top-color: rgba(30, 58, 86, 0.95);
    opacity: 1;
  }
}

/* ---------- 三层剖面 ---------- */
.page-about .about-strata-wrap {
  margin: 0;
}
.page-about .about-strata {
  display: block;
  width: 100%;
  height: auto;
  background: linear-gradient(160deg, #0D1B2A 0%, #0A1622 100%);
  border: 1px solid var(--ink-500);
}
.page-about .about-strata .st-name {
  font-family: var(--font-display);
  font-size: 34px;
  font-weight: 700;
  letter-spacing: -0.01em;
}
.page-about .about-strata .st-meta {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.05em;
}

/* ---------- 团队 ---------- */
.page-about .about-team__fig {
  margin: 0;
}
.page-about .about-team__fig .fh-figure__media {
  aspect-ratio: 3 / 2;
}
.page-about .about-team__body {
  min-width: 0;
}
.page-about .about-roles {
  margin: 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--about-hair);
}
.page-about .about-role {
  padding: 16px 0;
  border-bottom: 1px solid var(--about-hair);
}
.page-about .about-role__name {
  margin: 0 0 6px;
  font-family: var(--font-display);
  font-size: 1.12rem;
  letter-spacing: -0.005em;
  color: var(--cyan-pulse);
}
.page-about .about-role__desc {
  margin: 0;
  font-size: 0.93rem;
  line-height: 1.75;
  color: var(--about-body);
}

/* ---------- 发展历程轨道 ---------- */
.page-about .about-rail {
  display: flex;
  gap: 14px;
  margin: 0 0 clamp(24px, 4vw, 40px);
  padding: 4px 0 18px;
  overflow-x: auto;
  scroll-snap-type: x proximity;
  -webkit-overflow-scrolling: touch;
}
.page-about .about-rail:focus-visible {
  outline: 2px solid var(--cyan-pulse);
  outline-offset: 4px;
}
.page-about .about-node {
  flex: 0 0 clamp(232px, 68vw, 296px);
  scroll-snap-align: start;
  padding: 20px 18px 22px;
  background: var(--ink-700);
  border: 1px solid var(--ink-500);
  border-top: 3px solid var(--orange-signal);
}
.page-about .about-node:nth-child(even) {
  border-top-color: var(--ember);
}
.page-about .about-node:last-child {
  border-top-color: var(--cyan-pulse);
}
.page-about .about-node__no {
  display: block;
  font-size: 1.85rem;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--orange-signal);
}
.page-about .about-node:last-child .about-node__no {
  font-size: 2.7rem;
  color: var(--cyan-pulse);
}
.page-about .about-node__stage {
  margin: 12px 0 10px;
  font-size: 0.72rem;
  letter-spacing: 0.1em;
  color: var(--fog);
}
.page-about .about-node__title {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-size: 1.24rem;
  line-height: 1.16;
  letter-spacing: -0.008em;
  color: var(--mist);
}
.page-about .about-node__text {
  margin: 0;
  font-size: 0.9rem;
  line-height: 1.72;
  color: var(--about-body);
}
.page-about .about-archive__fig {
  margin: 0;
}

/* ---------- 服务地区（奶油纸） ---------- */
.page-about .about-sec--paper {
  margin-top: clamp(12px, 2vw, 24px);
  padding: clamp(32px, 5vw, 56px) clamp(22px, 4vw, 48px);
  background: var(--paper);
  border-top: 0;
}
.page-about .about-sec--paper .fh-kicker,
.page-about .about-sec--paper .about-sec__title {
  color: var(--ink-black);
}
.page-about .about-sec--paper .about-sec__title {
  max-width: 26ch;
}
.page-about .about-region__text {
  max-width: 62ch;
  margin: 0 0 1.05em;
  font-size: 1rem;
  line-height: 1.85;
  color: #2B2A26;
}
.page-about .about-region__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin: clamp(22px, 3vw, 34px) 0 0;
}
.page-about .about-sec--paper .fh-btn--signal {
  color: var(--paper);
}
.page-about .about-sec--paper .fh-btn--ghost {
  color: var(--ink-black);
  border-color: rgba(16, 16, 14, 0.4);
}
.page-about .about-sec--paper .fh-btn--ghost:hover {
  border-color: var(--ember);
  color: var(--ember);
}

/* ---------- 窄屏微调 ---------- */
@media (max-width: 480px) {
  .page-about .about-hero__stats {
    gap: 16px 24px;
  }
  .page-about .about-stat {
    min-width: 96px;
  }
  .page-about .about-sec--paper {
    padding-left: 18px;
    padding-right: 18px;
  }
}

/* ---------- 减少动效 ---------- */
@media (prefers-reduced-motion: reduce) {
  .page-about .about-claim,
  .page-about .about-claim__more,
  .page-about .about-toc__list a {
    transition: none !important;
  }
  .page-about .about-claim:hover {
    transform: none;
  }
  .page-about .about-rail {
    scroll-behavior: auto;
  }
}