.page-about {
  --about-pad: clamp(52px, 7vw, 108px);
  --about-gap: clamp(20px, 3.4vw, 48px);
  background: var(--ink);
  color: var(--paper);
  font-family: var(--font-body);
  font-size: var(--step-body);
  line-height: 1.75;
  overflow-x: hidden;
}

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

.page-about h1,
.page-about h2,
.page-about h3 {
  margin: 0;
  font-family: var(--font-display);
  letter-spacing: -0.035em;
  line-height: 1.08;
}

.page-about p {
  margin: 0;
}

.page-about .about-h2 {
  font-size: clamp(30px, 4.6vw, 62px);
  font-weight: 800;
  margin-top: 14px;
}

.page-about .about-lead {
  margin-top: 18px;
  max-width: 52ch;
  color: var(--haze);
  font-size: var(--step-3);
  line-height: 1.8;
}

.page-about [data-reveal].is-visible {
  animation: about-rise 0.72s var(--ease) both;
}

@keyframes about-rise {
  from {
    opacity: 0.001;
    transform: translateY(18px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding-block: clamp(22px, 4vw, 44px) clamp(38px, 6vw, 78px);
  background:
    radial-gradient(90% 80% at 88% -20%, rgba(24, 167, 159, 0.28), transparent 62%),
    radial-gradient(70% 70% at -10% 110%, rgba(255, 107, 74, 0.16), transparent 68%),
    var(--ink);
}

.page-about .about-hero__grid {
  display: grid;
  gap: clamp(26px, 4vw, 56px);
}

.page-about .about-hero__title {
  margin-top: 0.32em;
  font-size: clamp(38px, 7.4vw, 104px);
  font-weight: 800;
  letter-spacing: -0.045em;
  color: var(--paper);
}

.page-about .about-hero__title em {
  font-style: normal;
  color: var(--shallow);
}

.page-about .about-hero__lead {
  margin-top: 24px;
  max-width: 46ch;
  font-size: var(--step-3);
  line-height: 1.85;
  color: var(--haze);
}

.page-about .about-facts {
  list-style: none;
  margin: 14px 0 0;
  padding: 0;
  border-top: 1px solid var(--line);
}

.page-about .about-facts__item {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 14px;
  padding: 11px 0;
  border-bottom: 1px solid var(--line-soft);
}

.page-about .about-facts__key {
  font-size: var(--step-index);
  letter-spacing: 0.18em;
  color: var(--haze);
}

.page-about .about-facts__val {
  font-family: var(--font-mono);
  font-size: clamp(18px, 2.2vw, 24px);
  font-weight: 600;
  font-variant-numeric: tabular-nums;
  color: var(--shallow);
}

.page-about .about-hero__strip {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 26px;
  margin-top: clamp(26px, 4vw, 48px);
  padding-top: 18px;
  border-top: 1px solid var(--line);
}

.page-about .about-link {
  color: var(--paper);
  text-decoration: none;
  font-size: 14px;
  padding-bottom: 2px;
  border-bottom: 1px solid transparent;
  transition: color 0.3s var(--ease), border-color 0.3s var(--ease);
}

.page-about .about-link:hover,
.page-about .about-link:focus-visible {
  color: var(--coral);
  border-bottom-color: var(--coral);
}

/* ---------- 起点 ---------- */
.page-about .about-start {
  padding-block: var(--about-pad);
}

.page-about .about-start__grid {
  display: grid;
  gap: clamp(22px, 3.4vw, 48px);
}

.page-about .about-start__body {
  color: var(--brown);
  max-width: 62ch;
}

.page-about .about-start__body p + p {
  margin-top: 1.1em;
}

.page-about .about-stats {
  display: grid;
  gap: 0;
  border-top: 1px solid var(--line-ink);
  padding-top: 6px;
}

.page-about .about-stat {
  padding: 16px 0;
  border-bottom: 1px solid var(--line-ink);
}

.page-about .about-stat__num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(30px, 4.6vw, 56px);
  font-weight: 600;
  line-height: 1;
  font-variant-numeric: tabular-nums;
  letter-spacing: -0.02em;
  color: var(--brown);
}

.page-about .about-stat__unit {
  font-size: 0.42em;
  margin-left: 0.12em;
  color: var(--tide);
}

.page-about .about-stat__label {
  display: block;
  margin-top: 8px;
  font-size: var(--step-index);
  letter-spacing: 0.16em;
  color: var(--tide);
}

/* ---------- 协作台 ---------- */
.page-about .about-crew {
  padding-block: var(--about-pad);
  background:
    radial-gradient(80% 60% at 10% 0%, rgba(11, 77, 90, 0.75), transparent 70%),
    var(--ink);
}

.page-about .about-crew__grid {
  display: grid;
  gap: 16px;
  margin-top: clamp(26px, 4vw, 48px);
}

.page-about .crew-card {
  padding: clamp(20px, 3vw, 32px);
  border-radius: var(--radius-organic);
  transition: transform 0.4s var(--ease);
}

.page-about .crew-card:hover {
  transform: translateY(-4px);
}

.page-about .crew-card__num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(34px, 5vw, 62px);
  font-weight: 600;
  line-height: 1;
  font-variant-numeric: tabular-nums;
  letter-spacing: -0.03em;
}

.page-about .crew-card__title {
  margin: 10px 0 12px;
  font-size: clamp(18px, 1.7vw, 22px);
  font-weight: 700;
}

.page-about .crew-card p {
  font-size: 15px;
  line-height: 1.8;
}

.page-about .crew-card--data {
  background: var(--tide);
  color: var(--paper);
}

.page-about .crew-card--data .crew-card__num {
  color: var(--shallow);
}

.page-about .crew-card--review {
  background: var(--ink-2);
  color: var(--paper);
  border-left: 3px solid var(--coral);
  border-radius: 4px var(--radius-m) var(--radius-m) 4px;
}

.page-about .crew-card--review .crew-card__num {
  color: var(--coral);
}

.page-about .crew-card--review p {
  color: var(--haze);
}

.page-about .crew-card--product {
  background: var(--coral-mist);
  color: var(--brown);
}

.page-about .crew-card--product .crew-card__num {
  color: var(--tide);
}

.page-about .about-crew__figure {
  margin: 10px 0 0;
}

/* ---------- 时间轴 ---------- */
.page-about .about-timeline {
  padding-block: var(--about-pad);
  background:
    radial-gradient(80% 70% at 100% 0%, rgba(24, 167, 159, 0.18), transparent 62%),
    var(--ink-2);
}

.page-about .about-timeline__head {
  max-width: 62ch;
}

.page-about .timeline {
  list-style: none;
  margin: clamp(28px, 4vw, 54px) 0 0;
  padding: 0;
}

.page-about .timeline__item {
  position: relative;
  padding: 0 0 26px 26px;
  border-left: 1px solid var(--line);
  display: grid;
  gap: 8px;
}

.page-about .timeline__item:last-child {
  padding-bottom: 0;
}

.page-about .timeline__item::before {
  content: "";
  position: absolute;
  left: -5px;
  top: 9px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--leyu);
  box-shadow: 0 0 0 4px rgba(24, 167, 159, 0.16);
  transition: background 0.3s var(--ease), box-shadow 0.3s var(--ease);
}

.page-about .timeline__item:hover::before,
.page-about .timeline__item:focus-within::before {
  background: var(--coral);
  box-shadow: 0 0 0 5px rgba(255, 107, 74, 0.22);
}

.page-about .timeline__item:focus-visible {
  outline: 1px dashed var(--leyu);
  outline-offset: 6px;
}

.page-about .timeline__year {
  font-family: var(--font-mono);
  font-size: clamp(18px, 2.2vw, 22px);
  font-weight: 600;
  letter-spacing: 0.02em;
  color: var(--shallow);
}

.page-about .timeline__title {
  font-size: clamp(19px, 1.9vw, 24px);
  font-weight: 700;
  color: var(--paper);
}

.page-about .timeline__note {
  margin-top: 8px;
  color: var(--haze);
  font-size: 15px;
  line-height: 1.8;
  max-width: 46ch;
}

.page-about .timeline__more {
  margin-top: 0;
  max-height: 0;
  overflow: hidden;
  opacity: 0;
  color: var(--shallow);
  font-size: 14px;
  line-height: 1.8;
  max-width: 46ch;
  transition: max-height 0.5s var(--ease), opacity 0.4s var(--ease), margin-top 0.4s var(--ease);
}

.page-about .timeline__item:hover .timeline__more,
.page-about .timeline__item:focus-within .timeline__more {
  max-height: 180px;
  opacity: 1;
  margin-top: 8px;
}

/* ---------- 生产流程 ---------- */
.page-about .about-flow {
  padding-block: var(--about-pad);
}

.page-about .about-flow__grid {
  display: grid;
  gap: clamp(22px, 3.4vw, 44px);
}

.page-about .about-flow__lead {
  margin-top: 18px;
  max-width: 42ch;
  color: var(--brown);
  font-size: var(--step-3);
  line-height: 1.8;
}

.page-about .flow-steps {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .flow-step {
  padding: 20px 0;
  border-top: 1px solid var(--line-ink);
  display: grid;
  gap: 6px;
  color: var(--brown);
}

.page-about .flow-step:last-child {
  border-bottom: 1px solid var(--line-ink);
}

.page-about .flow-step__no {
  color: var(--coral);
  font-family: var(--font-mono);
  letter-spacing: 0.16em;
}

.page-about .flow-step__title {
  font-size: clamp(18px, 1.8vw, 22px);
  font-weight: 700;
}

.page-about .flow-step p {
  font-size: 15px;
  line-height: 1.85;
  color: var(--brown);
}

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

/* ---------- 服务范围 ---------- */
.page-about .about-reach {
  padding-block: var(--about-pad);
  background: linear-gradient(165deg, var(--tide) 0%, var(--ink) 68%);
}

.page-about .about-reach__grid {
  display: grid;
  gap: clamp(24px, 4vw, 48px);
}

.page-about .reach-list {
  list-style: none;
  margin: clamp(22px, 3vw, 34px) 0 0;
  padding: 0;
  display: grid;
  gap: 12px;
  max-width: 56ch;
}

.page-about .reach-list li {
  position: relative;
  padding-left: 20px;
  font-size: 15px;
  line-height: 1.8;
  color: var(--haze);
}

.page-about .reach-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.68em;
  width: 8px;
  height: 2px;
  background: var(--coral);
}

.page-about .about-next {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: clamp(24px, 3.4vw, 38px);
}

.page-about .reach-card {
  padding: clamp(20px, 3vw, 30px);
  border: 1px solid var(--line);
  border-radius: var(--radius-m);
  background: rgba(244, 235, 221, 0.05);
  backdrop-filter: blur(2px);
}

.page-about .reach-card__row {
  display: grid;
  gap: 3px;
  padding: 14px 0;
  border-bottom: 1px solid var(--line-soft);
}

.page-about .reach-card__row:last-child {
  border-bottom: 0;
  padding-bottom: 0;
}

.page-about .reach-card__key {
  font-size: var(--step-index);
  letter-spacing: 0.18em;
  color: var(--haze);
}

.page-about .reach-card__val {
  font-family: var(--font-mono);
  font-size: clamp(14px, 1.4vw, 16px);
  color: var(--shallow);
  text-decoration: none;
  word-break: break-all;
  transition: color 0.3s var(--ease);
}

.page-about .reach-card__val:hover,
.page-about .reach-card__val:focus-visible {
  color: var(--coral);
}

.page-about .reach-card__hint {
  font-size: 13px;
  line-height: 1.7;
  color: var(--haze);
}

.page-about .about-reach__figure {
  margin: clamp(28px, 4vw, 52px) 0 0;
}

/* ---------- 桌面布局 ---------- */
@media (min-width: 700px) {
  .page-about .flow-step {
    grid-template-columns: 52px minmax(0, 0.85fr) minmax(0, 1.15fr);
    gap: 0 24px;
    align-items: baseline;
  }

  .page-about .about-stats {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    border-bottom: 1px solid var(--line-ink);
  }

  .page-about .about-stat {
    padding: 20px 22px 18px 0;
    border-bottom: 0;
    border-right: 1px solid var(--line-ink);
  }

  .page-about .about-stat:last-child {
    border-right: 0;
  }

  .page-about .timeline__item {
    grid-template-columns: 118px minmax(0, 1fr);
    gap: 0 32px;
    padding-left: 34px;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.45fr) minmax(230px, 0.55fr);
    align-items: end;
  }

  .page-about .about-start__grid {
    grid-template-columns: minmax(0, 0.85fr) minmax(0, 1.15fr);
    align-items: start;
  }

  .page-about .about-start__head {
    position: sticky;
    top: 96px;
  }

  .page-about .about-stats {
    grid-column: 1 / -1;
  }

  .page-about .about-crew__grid {
    grid-template-columns: 1.15fr 0.95fr 0.8fr;
    align-items: start;
    gap: 18px;
  }

  .page-about .about-crew__figure {
    grid-column: 1 / -1;
    margin-top: 12px;
  }

  .page-about .about-reach__grid {
    grid-template-columns: minmax(0, 1.2fr) minmax(0, 0.8fr);
    align-items: start;
  }

  .page-about .reach-card {
    margin-top: 8px;
  }
}

@media (min-width: 1000px) {
  .page-about .about-flow__grid {
    grid-template-columns: minmax(0, 1fr) minmax(0, 0.95fr);
    gap: clamp(32px, 5vw, 72px);
    align-items: start;
  }

  .page-about .about-flow__head {
    grid-column: 1;
    grid-row: 1;
  }

  .page-about .flow-steps {
    grid-column: 1;
    grid-row: 2;
  }

  .page-about .about-flow__figure {
    grid-column: 2;
    grid-row: 1 / span 2;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about [data-reveal].is-visible {
    animation: none;
  }

  .page-about .crew-card,
  .page-about .timeline__more,
  .page-about .about-link,
  .page-about .reach-card__val {
    transition: none;
  }

  .page-about .crew-card:hover {
    transform: none;
  }

  .page-about .timeline__more {
    max-height: none;
    opacity: 1;
    margin-top: 8px;
  }
}