.page-about {
  --about-card: rgba(16, 84, 62, 0.55);
  --about-card-strong: rgba(16, 84, 62, 0.86);
  --about-stage: clamp(56px, 8vw, 112px);
  background: var(--fh-ink);
  color: var(--fh-text);
  overflow-x: clip;
}

.page-about__crumb {
  padding-top: 22px;
  padding-bottom: 6px;
}

/* ---------- 首屏 ---------- */
.page-about__hero {
  position: relative;
  overflow: hidden;
  padding: 36px 0 60px;
  background:
    radial-gradient(760px 420px at 84% 4%, rgba(0, 229, 199, 0.18), transparent 62%),
    radial-gradient(560px 360px at 2% 98%, rgba(255, 107, 53, 0.14), transparent 68%),
    linear-gradient(180deg, var(--fh-ink) 0%, var(--fh-forest) 100%);
  border-bottom: 1px solid var(--fh-line);
}

.page-about__hero::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    repeating-linear-gradient(0deg, rgba(0, 229, 199, 0.05) 0 1px, transparent 1px 68px),
    repeating-linear-gradient(90deg, rgba(0, 229, 199, 0.05) 0 1px, transparent 1px 68px);
}

.page-about__hero > .fh-container {
  position: relative;
  z-index: 1;
}

.page-about__eyebrow {
  margin: 0 0 16px;
  font-family: var(--fh-display);
  font-size: var(--fh-fs-12);
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--fh-cyan);
}

.page-about__title {
  margin: 0 0 20px;
  font-family: var(--fh-display);
  font-size: clamp(2.1rem, 9vw, 5rem);
  line-height: 1.04;
  letter-spacing: 0.01em;
  color: var(--fh-text);
  text-wrap: balance;
}

.page-about__lead {
  margin: 0 0 34px;
  max-width: 62ch;
  font-size: var(--fh-fs-16);
  line-height: 1.75;
  color: var(--fh-text);
}

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

.page-about__fact {
  min-width: 0;
  padding: 14px 16px;
  background: rgba(6, 17, 13, 0.72);
}

.page-about__fact dt {
  margin-bottom: 6px;
  font-size: var(--fh-fs-12);
  letter-spacing: 0.14em;
  color: var(--fh-muted);
}

.page-about__fact dd {
  margin: 0;
  font-size: clamp(1.15rem, 5vw, 1.75rem);
  line-height: 1.1;
  color: var(--fh-text);
  overflow-wrap: anywhere;
}

.page-about__unit {
  margin-left: 4px;
  font-size: var(--fh-fs-14);
  color: var(--fh-orange);
}

/* ---------- 通用章节 ---------- */
.page-about__section {
  padding: var(--about-stage) 0;
}

.page-about__head {
  display: grid;
  grid-template-columns: auto 6px minmax(0, 1fr);
  column-gap: 14px;
  row-gap: 8px;
  align-items: start;
  margin-bottom: 36px;
}

.page-about__head .fh-section__no {
  grid-row: 1 / span 2;
  font-family: var(--fh-mono);
  font-size: var(--fh-fs-20);
  color: var(--fh-cyan);
  line-height: 1.2;
}

.page-about__head .fh-section__ribbon {
  grid-row: 1 / span 2;
  width: 6px;
  height: 100%;
  min-height: 42px;
  border-radius: 999px;
  background: linear-gradient(180deg, var(--fh-cyan), rgba(0, 229, 199, 0.05));
}

.page-about__head-title {
  grid-column: 3;
  margin: 0;
  font-family: var(--fh-display);
  font-size: clamp(1.5rem, 5.4vw, 2.5rem);
  line-height: 1.16;
  letter-spacing: 0.01em;
  color: var(--fh-text);
}

.page-about__head-lead {
  grid-column: 3;
  margin: 0;
  max-width: 56ch;
  font-size: var(--fh-fs-14);
  line-height: 1.8;
  color: var(--fh-muted);
}

/* ---------- 起源 ---------- */
.page-about__origin {
  background: linear-gradient(180deg, var(--fh-forest) 0%, var(--fh-ink) 100%);
}

.page-about__origin-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 26px;
}

.page-about__origin-text p {
  margin: 0 0 18px;
  max-width: 68ch;
  font-size: var(--fh-fs-16);
  line-height: 1.8;
  color: var(--fh-text);
}

.page-about__origin-text p:last-child {
  margin-bottom: 0;
}

.page-about__panel {
  padding: 24px 22px;
  border: 1px solid var(--fh-line);
  border-left: 3px solid var(--fh-orange);
  border-radius: var(--fh-radius);
  background: var(--about-card);
  box-shadow: var(--fh-shadow);
}

.page-about__panel-no {
  margin: 0 0 10px;
  font-size: var(--fh-fs-44);
  line-height: 1;
  color: var(--fh-orange);
}

.page-about__panel-title {
  margin: 0 0 12px;
  font-family: var(--fh-display);
  font-size: var(--fh-fs-20);
  letter-spacing: 0.02em;
  color: var(--fh-text);
}

.page-about__panel-body {
  margin: 0 0 12px;
  font-size: var(--fh-fs-14);
  line-height: 1.75;
  color: var(--fh-muted);
}

.page-about__panel-body:last-child {
  margin-bottom: 0;
}

/* ---------- 年份长卷 ---------- */
.page-about__timeline {
  position: relative;
  overflow: hidden;
  background: linear-gradient(180deg, var(--fh-forest) 0%, var(--fh-ink) 46%, var(--fh-ink) 100%);
}

.page-about__timeline-img {
  position: absolute;
  inset: 0;
  z-index: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.14;
  filter: saturate(0.7) contrast(1.1);
  pointer-events: none;
}

.page-about__timeline-inner {
  position: relative;
  z-index: 1;
}

.page-about__yearnav {
  display: flex;
  gap: 10px;
  overflow-x: auto;
  margin-bottom: 30px;
  padding: 4px 2px 12px;
  scrollbar-width: thin;
}

.page-about__yearnav a {
  flex: 0 0 auto;
  padding: 8px 16px;
  border: 1px solid var(--fh-line);
  border-radius: 999px;
  font-family: var(--fh-mono);
  font-size: var(--fh-fs-14);
  color: var(--fh-cyan);
  text-decoration: none;
  transition: background-color 0.2s ease, border-color 0.2s ease, color 0.2s ease;
}

.page-about__yearnav a:hover,
.page-about__yearnav a:focus-visible {
  border-color: var(--fh-cyan);
  background: rgba(0, 229, 199, 0.14);
  color: var(--fh-cyan-soft);
}

.page-about__track {
  position: relative;
  display: grid;
  gap: 24px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about__node {
  position: relative;
  display: grid;
  grid-template-columns: 1fr;
  gap: 10px;
}

.page-about__year {
  display: block;
  font-family: var(--fh-mono);
  font-size: var(--fh-fs-44);
  line-height: 1;
  letter-spacing: 0.02em;
  color: var(--fh-cyan);
}

.page-about__node-body {
  padding: 20px 20px 22px;
  border: 1px solid var(--fh-line);
  border-radius: var(--fh-radius);
  background: linear-gradient(160deg, var(--about-card-strong), rgba(11, 61, 46, 0.5));
}

.page-about__node-title {
  margin: 0 0 10px;
  font-family: var(--fh-display);
  font-size: var(--fh-fs-20);
  letter-spacing: 0.02em;
  color: var(--fh-text);
}

.page-about__node-body p {
  margin: 0;
  font-size: var(--fh-fs-14);
  line-height: 1.8;
  color: var(--fh-muted);
}

/* ---------- 流程 ---------- */
.page-about__steps {
  display: grid;
  gap: 14px;
  margin: 0 0 30px;
  padding: 0;
  list-style: none;
}

.page-about__step {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 16px;
  padding: 18px 18px 20px;
  border: 1px solid var(--fh-line);
  border-radius: var(--fh-radius-sm);
  background: rgba(16, 84, 62, 0.34);
  transition: border-color 0.2s ease, background-color 0.2s ease, transform 0.2s ease;
}

.page-about__step:hover,
.page-about__step:focus-within {
  border-color: var(--fh-cyan);
  background: rgba(16, 84, 62, 0.62);
  transform: translateY(-2px);
}

.page-about__step-no {
  font-size: var(--fh-fs-20);
  line-height: 1.2;
  color: var(--fh-cyan);
}

.page-about__step-title {
  margin: 0 0 8px;
  font-family: var(--fh-display);
  font-size: var(--fh-fs-20);
  letter-spacing: 0.02em;
  color: var(--fh-text);
}

.page-about__step-main p {
  margin: 0;
  font-size: var(--fh-fs-14);
  line-height: 1.75;
  color: var(--fh-muted);
}

.page-about__figure {
  margin: 0 0 24px;
}

.page-about__slots {
  display: grid;
  gap: 12px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about__slot {
  display: grid;
  grid-template-columns: auto auto minmax(0, 1fr);
  align-items: baseline;
  gap: 8px;
  padding: 14px 16px;
  border-radius: var(--fh-radius-sm);
  border: 1px solid var(--fh-line);
  background: rgba(6, 17, 13, 0.66);
}

.page-about__slot-num {
  font-size: var(--fh-fs-28);
  line-height: 1;
  color: var(--fh-orange);
}

.page-about__slot-unit {
  font-size: var(--fh-fs-12);
  letter-spacing: 0.1em;
  color: var(--fh-orange-soft);
}

.page-about__slot p {
  grid-column: 1 / -1;
  margin: 0;
  font-size: var(--fh-fs-14);
  line-height: 1.7;
  color: var(--fh-muted);
}

/* ---------- 团队 ---------- */
.page-about__team {
  background: linear-gradient(180deg, var(--fh-ink) 0%, var(--fh-forest) 58%, var(--fh-ink) 100%);
}

.page-about__team-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 28px;
}

.page-about__team-chart {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 16px;
  padding: 26px 20px;
  border: 1px solid var(--fh-line);
  border-radius: var(--fh-radius);
  background: rgba(6, 17, 13, 0.62);
}

.page-about__donut {
  width: min(240px, 72vw);
  height: auto;
}

.page-about__donut-num {
  font-family: var(--fh-mono);
  font-size: 28px;
  fill: var(--fh-text);
}

.page-about__donut-label {
  font-family: var(--fh-body);
  font-size: 11px;
  letter-spacing: 0.16em;
  fill: var(--fh-muted);
}

.page-about__chart-note {
  margin: 0;
  max-width: 30ch;
  font-size: var(--fh-fs-14);
  line-height: 1.75;
  color: var(--fh-muted);
  text-align: center;
}

.page-about__roles {
  display: grid;
  gap: 14px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about__role {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto;
  align-items: center;
  gap: 6px 12px;
  padding: 18px 18px 20px;
  border: 1px solid var(--fh-line);
  border-radius: var(--fh-radius-sm);
  background: rgba(16, 84, 62, 0.42);
}

.page-about__role-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
}

.page-about__role-dot--a { background: var(--fh-cyan); }
.page-about__role-dot--b { background: var(--fh-cyan-soft); }
.page-about__role-dot--c { background: var(--fh-orange); }
.page-about__role-dot--d { background: var(--fh-orange-soft); }

.page-about__role-name {
  margin: 0;
  font-family: var(--fh-display);
  font-size: var(--fh-fs-20);
  letter-spacing: 0.02em;
  color: var(--fh-text);
}

.page-about__role-num {
  font-size: var(--fh-fs-14);
  color: var(--fh-cyan);
  white-space: nowrap;
}

.page-about__role-desc {
  grid-column: 1 / -1;
  margin: 8px 0 0;
  font-size: var(--fh-fs-14);
  line-height: 1.75;
  color: var(--fh-muted);
}

.page-about__team-photo {
  margin: 30px 0 0;
}

/* ---------- 覆盖范围 ---------- */
.page-about__reach-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 24px;
  margin-bottom: 32px;
}

.page-about__reach-main {
  padding: 26px 22px;
  border-radius: var(--fh-radius);
  background: linear-gradient(150deg, rgba(0, 229, 199, 0.14), rgba(16, 84, 62, 0.5));
  border: 1px solid var(--fh-line);
}

.page-about__reach-num {
  margin: 0 0 12px;
  font-size: clamp(3rem, 16vw, var(--fh-fs-72));
  line-height: 1;
  color: var(--fh-cyan);
}

.page-about__reach-lead {
  margin: 0;
  max-width: 46ch;
  font-size: var(--fh-fs-14);
  line-height: 1.8;
  color: var(--fh-text);
}

.page-about__reach-list {
  display: grid;
  gap: 1px;
  margin: 0;
  padding: 0;
  list-style: none;
  background: var(--fh-line);
  border: 1px solid var(--fh-line);
  border-radius: var(--fh-radius-sm);
  overflow: hidden;
}

.page-about__reach-item {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: 6px 16px;
  padding: 14px 18px;
  background: rgba(6, 17, 13, 0.74);
}

.page-about__reach-key {
  font-size: var(--fh-fs-14);
  color: var(--fh-muted);
}

.page-about__reach-val {
  font-size: var(--fh-fs-16);
  color: var(--fh-text);
}

.page-about__mix {
  padding: 24px 22px;
  border: 1px solid var(--fh-line);
  border-radius: var(--fh-radius);
  background: rgba(16, 84, 62, 0.34);
}

.page-about__mix-title {
  margin: 0 0 20px;
  font-family: var(--fh-display);
  font-size: var(--fh-fs-20);
  letter-spacing: 0.02em;
  color: var(--fh-text);
}

.page-about__mix-list {
  display: grid;
  gap: 18px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about__mix-item {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  align-items: center;
  gap: 6px 12px;
}

.page-about__mix-pct {
  font-size: var(--fh-fs-14);
  color: var(--fh-orange);
}

.page-about__mix-item .fh-bar__track {
  grid-column: 1 / -1;
}

.page-about__fill-60 { width: 60%; background: var(--fh-cyan); }
.page-about__fill-25 { width: 25%; }
.page-about__fill-15 { width: 15%; background: var(--fh-cyan-soft); }

/* ---------- 标准与认可 ---------- */
.page-about__trust {
  background: linear-gradient(180deg, var(--fh-ink) 0%, var(--fh-forest) 100%);
}

.page-about__trust-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
}

.page-about__trust-card {
  padding: 22px 20px 24px;
  border: 1px solid var(--fh-line);
  border-top: 3px solid var(--fh-cyan);
  border-radius: var(--fh-radius-sm);
  background: rgba(6, 17, 13, 0.66);
}

.page-about__trust-card:nth-child(even) {
  border-top-color: var(--fh-orange);
}

.page-about__trust-title {
  margin: 0 0 10px;
  font-family: var(--fh-display);
  font-size: var(--fh-fs-20);
  letter-spacing: 0.02em;
  color: var(--fh-text);
}

.page-about__trust-card p {
  margin: 0;
  font-size: var(--fh-fs-14);
  line-height: 1.8;
  color: var(--fh-muted);
}

/* ---------- 下一步 ---------- */
.page-about__next {
  padding-bottom: clamp(88px, 14vw, 180px);
  background:
    radial-gradient(620px 340px at 88% 12%, rgba(255, 107, 53, 0.16), transparent 66%),
    var(--fh-ink);
}

.page-about__next-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
  margin-bottom: 36px;
}

.page-about__next-card {
  padding: 22px 20px 24px;
  border: 1px solid var(--fh-line);
  border-radius: var(--fh-radius);
  background: rgba(16, 84, 62, 0.46);
}

.page-about__next-title {
  margin: 14px 0 10px;
  font-family: var(--fh-display);
  font-size: var(--fh-fs-20);
  line-height: 1.28;
  letter-spacing: 0.02em;
  color: var(--fh-text);
}

.page-about__next-card p {
  margin: 0;
  font-size: var(--fh-fs-14);
  line-height: 1.8;
  color: var(--fh-muted);
}

.page-about__next-cta {
  padding: 26px 22px 28px;
  border-radius: var(--fh-radius);
  border: 1px solid rgba(0, 229, 199, 0.34);
  background: linear-gradient(140deg, rgba(16, 84, 62, 0.72), rgba(6, 17, 13, 0.9));
}

.page-about__next-lead {
  margin: 0 0 22px;
  max-width: 62ch;
  font-size: var(--fh-fs-16);
  line-height: 1.8;
  color: var(--fh-text);
}

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

/* ---------- 响应式 ---------- */
@media (min-width: 620px) {
  .page-about__facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

@media (min-width: 900px) {
  .page-about__hero {
    padding: 56px 0 84px;
  }

  .page-about__origin-grid {
    grid-template-columns: 7fr 5fr;
    gap: 44px;
    align-items: start;
  }

  .page-about__track {
    gap: 36px;
  }

  .page-about__track::before {
    content: "";
    position: absolute;
    left: 219px;
    top: 14px;
    bottom: 14px;
    width: 2px;
    background: linear-gradient(180deg, var(--fh-cyan), rgba(0, 229, 199, 0.06));
  }

  .page-about__node {
    grid-template-columns: 200px minmax(0, 1fr);
    gap: 48px;
    align-items: start;
  }

  .page-about__node::before {
    content: "";
    position: absolute;
    left: 214px;
    top: 26px;
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: var(--fh-ink);
    border: 2px solid var(--fh-cyan);
  }

  .page-about__year {
    font-size: var(--fh-fs-72);
    text-align: right;
    padding-right: 10px;
  }

  .page-about__node-body {
    padding: 24px 26px 26px;
  }

  .page-about__node:nth-child(even) .page-about__node-body {
    margin-left: 54px;
  }

  .page-about__node:nth-child(odd) .page-about__node-body {
    margin-right: 54px;
  }

  .page-about__process-grid {
    display: grid;
    grid-template-columns: 7fr 5fr;
    gap: 40px;
    align-items: start;
  }

  .page-about__steps {
    margin-bottom: 0;
  }

  .page-about__team-grid {
    grid-template-columns: 4fr 8fr;
    gap: 36px;
    align-items: start;
  }

  .page-about__team-chart {
    position: sticky;
    top: 104px;
  }

  .page-about__team-photo {
    max-width: 520px;
    margin-top: 36px;
  }

  .page-about__reach-grid {
    grid-template-columns: 5fr 7fr;
    gap: 32px;
  }

  .page-about__mix {
    padding: 28px 30px;
  }

  .page-about__next-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 18px;
  }

  .page-about__next-card:nth-child(even) {
    margin-top: 28px;
  }

  .page-about__next-cta {
    display: grid;
    grid-template-columns: minmax(0, 1fr) auto;
    gap: 28px;
    align-items: center;
    padding: 32px 34px;
  }

  .page-about__next-lead {
    margin-bottom: 0;
  }
}

@media (min-width: 1180px) {
  .page-about__trust-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about__step,
  .page-about__yearnav a {
    transition: none;
  }

  .page-about__step:hover,
  .page-about__step:focus-within {
    transform: none;
  }
}