.page-about {
  --about-dot: 11px;
  --about-track: rgba(255, 106, 43, 0.5);
  background: var(--yh-paper);
  color: var(--yh-black);
}

.page-about h2,
.page-about h3 {
  margin: 0;
}

.page-about p {
  margin: 0;
}

/* ---------- 面包屑 ---------- */
.page-about .about-crumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin-bottom: clamp(24px, 4vw, 42px);
  font-size: 0.8125rem;
}

.page-about .about-crumbs .yh-crumbs__item {
  color: var(--yh-on-dark);
  letter-spacing: 0.04em;
}

.page-about .about-crumbs a.yh-crumbs__item {
  color: var(--yh-cyan);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color 180ms var(--yh-ease);
}

.page-about .about-crumbs a.yh-crumbs__item:hover,
.page-about .about-crumbs a.yh-crumbs__item:focus-visible {
  border-bottom-color: var(--yh-cyan);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow-x: clip;
  padding: clamp(26px, 4.5vw, 44px) 0 clamp(48px, 7vw, 88px);
  color: var(--yh-paper);
  background:
    radial-gradient(circle at 84% -12%, rgba(52, 224, 208, 0.2), transparent 52%),
    radial-gradient(circle at 4% 112%, rgba(255, 106, 43, 0.18), transparent 46%),
    linear-gradient(168deg, var(--yh-ink) 0%, var(--yh-ink-deep) 100%);
  border-bottom: 1px solid var(--yh-hair-dark);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(244, 235, 221, 0.055) 1px, transparent 1px),
    linear-gradient(90deg, rgba(244, 235, 221, 0.055) 1px, transparent 1px);
  background-size: 52px 52px;
  -webkit-mask-image: linear-gradient(180deg, rgba(0, 0, 0, 0.9), transparent 78%);
  mask-image: linear-gradient(180deg, rgba(0, 0, 0, 0.9), transparent 78%);
}

.page-about .about-hero .yh-shell {
  position: relative;
  z-index: 1;
}

.page-about .about-hero__grid {
  display: grid;
  gap: clamp(30px, 4vw, 52px);
  align-items: start;
}

.page-about .about-hero__lead .yh-label {
  display: inline-block;
  color: var(--yh-cyan);
}

.page-about .about-hero__title {
  margin: 16px 0 18px;
  font-family: var(--yh-font-display);
  font-weight: 800;
  font-size: clamp(2rem, 4.8vw, 3.5rem);
  line-height: 1.14;
  letter-spacing: -0.015em;
  color: var(--yh-paper);
  max-width: 16ch;
}

.page-about .about-hero__text {
  max-width: 46ch;
  font-family: var(--yh-font-body);
  font-size: 1.0625rem;
  line-height: 1.8;
  color: var(--yh-on-dark);
}

.page-about .about-hero__actions {
  margin-top: clamp(22px, 3vw, 30px);
  gap: 12px;
  flex-wrap: wrap;
}

.page-about .about-hero__facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
}

.page-about .about-fact {
  padding: 16px 16px 18px;
  border-radius: var(--yh-radius-s);
  border: 1px solid var(--yh-hair-dark);
  background: var(--yh-glass);
  -webkit-backdrop-filter: blur(7px);
  backdrop-filter: blur(7px);
}

.page-about .about-fact__num {
  display: block;
  font-size: 1.375rem;
  font-weight: 700;
  line-height: 1.2;
  color: var(--yh-cyan);
  letter-spacing: 0.01em;
}

.page-about .about-fact__label {
  display: block;
  margin-top: 8px;
  font-size: 0.75rem;
  line-height: 1.5;
  letter-spacing: 0.08em;
  color: var(--yh-on-dark-dim);
}

/* ---------- 章节骨架 ---------- */
.page-about .about-section {
  padding: clamp(48px, 8vw, 96px) 0;
  overflow-x: clip;
}

.page-about .about-section--paper {
  background: var(--yh-paper);
}

.page-about .about-section--soft {
  background: linear-gradient(180deg, var(--yh-paper-soft) 0%, var(--yh-paper) 100%);
}

.page-about .about-section--dark {
  background:
    radial-gradient(circle at 12% 8%, rgba(52, 224, 208, 0.14), transparent 48%),
    linear-gradient(180deg, var(--yh-ink) 0%, var(--yh-ink-soft) 100%);
  color: var(--yh-paper);
}

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

.page-about .about-section__head .yh-label {
  display: inline-block;
  color: var(--yh-teal);
}

.page-about .about-section__head--dark .yh-label {
  color: var(--yh-cyan);
}

.page-about .about-section__title {
  margin: 14px 0 16px;
  font-family: var(--yh-font-display);
  font-weight: 800;
  font-size: clamp(1.55rem, 3.2vw, 2.4rem);
  line-height: 1.22;
  letter-spacing: -0.01em;
  color: var(--yh-ink);
  max-width: 24ch;
}

.page-about .about-section__head--dark .about-section__title {
  color: var(--yh-paper);
}

.page-about .about-section__intro {
  font-size: 1rem;
  line-height: 1.85;
  color: rgba(17, 24, 32, 0.78);
}

.page-about .about-section__head--dark .about-section__intro {
  color: var(--yh-on-dark);
}

/* ---------- 沿革 ---------- */
.page-about .about-history {
  display: grid;
  gap: clamp(28px, 4vw, 46px);
  margin-top: clamp(28px, 4vw, 46px);
}

.page-about .about-timeline {
  position: relative;
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: clamp(20px, 3vw, 28px);
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 8px;
  bottom: 8px;
  width: 1px;
  background: linear-gradient(180deg, var(--yh-orange) 0%, var(--yh-cyan) 55%, rgba(216, 210, 196, 0.65) 100%);
}

.page-about .about-timeline__item {
  position: relative;
  padding-left: 34px;
}

.page-about .about-timeline__item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 6px;
  width: var(--about-dot);
  height: var(--about-dot);
  border-radius: 50%;
  background: var(--yh-paper);
  border: 2px solid var(--yh-orange);
  box-shadow: 0 0 0 4px rgba(255, 106, 43, 0.13);
}

.page-about .about-timeline__item:nth-child(even)::before {
  border-color: var(--yh-cyan);
  box-shadow: 0 0 0 4px rgba(52, 224, 208, 0.16);
}

.page-about .about-timeline__year {
  display: inline-block;
  font-size: 0.875rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  color: var(--yh-orange);
}

.page-about .about-timeline__item:nth-child(even) .about-timeline__year {
  color: var(--yh-teal);
}

.page-about .about-timeline__title {
  margin: 6px 0 6px;
  font-family: var(--yh-font-display);
  font-weight: 800;
  font-size: 1.0625rem;
  line-height: 1.4;
  color: var(--yh-ink);
}

.page-about .about-timeline__body p {
  font-size: 0.9375rem;
  line-height: 1.8;
  color: rgba(17, 24, 32, 0.76);
  max-width: 44ch;
}

/* ---------- 图版 ---------- */
.page-about .about-figure {
  margin: 0;
  border-radius: var(--yh-radius-m);
  overflow: hidden;
  background: var(--yh-paper-dim);
  border: 1px solid var(--yh-line);
  box-shadow: var(--yh-shadow);
}

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

.page-about .about-figure__cap {
  display: block;
  padding: 12px 16px;
  font-size: 0.6875rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--yh-ink);
  background: var(--yh-paper-dim);
  border-top: 1px solid var(--yh-line);
}

.page-about .about-section--dark .about-figure {
  background: rgba(244, 235, 221, 0.08);
  border-color: var(--yh-hair-dark);
}

.page-about .about-section--dark .about-figure__cap {
  background: rgba(244, 235, 221, 0.1);
  border-top-color: var(--yh-hair-dark);
  color: var(--yh-on-dark);
}

/* ---------- 原则折叠卡 ---------- */
.page-about .about-principles {
  display: grid;
  gap: 14px;
  margin-top: clamp(26px, 4vw, 40px);
  max-width: 860px;
}

.page-about .about-principle {
  padding: 2px 20px;
  border-radius: var(--yh-radius-m);
  background: var(--yh-paper-soft);
  border: 1px solid var(--yh-line);
  transition: border-color 200ms var(--yh-ease), box-shadow 200ms var(--yh-ease);
}

.page-about .about-principle[open] {
  border-color: rgba(255, 106, 43, 0.55);
  box-shadow: var(--yh-shadow);
}

.page-about .about-principle summary {
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding: 18px 0;
  cursor: pointer;
  list-style: none;
  font-family: var(--yh-font-display);
  font-weight: 800;
  font-size: 1rem;
  line-height: 1.5;
  color: var(--yh-ink);
}

.page-about .about-principle summary::-webkit-details-marker {
  display: none;
}

.page-about .about-principle summary::after {
  content: "+";
  margin-left: auto;
  font-family: var(--yh-font-mono);
  font-size: 1.25rem;
  line-height: 1;
  color: var(--yh-orange);
}

.page-about .about-principle[open] summary::after {
  content: "\2013";
}

.page-about .about-principle summary:focus-visible {
  outline: 2px solid var(--yh-cyan);
  outline-offset: 3px;
}

.page-about .about-principle__idx {
  flex: none;
  font-size: 0.75rem;
  letter-spacing: 0.14em;
  color: var(--yh-teal);
  border: 1px solid rgba(15, 94, 100, 0.4);
  border-radius: 4px;
  padding: 2px 6px;
}

.page-about .about-principle__body {
  padding: 0 0 20px;
  font-size: 0.9375rem;
  line-height: 1.85;
  color: rgba(17, 24, 32, 0.78);
  max-width: 62ch;
}

/* ---------- 团队 ---------- */
.page-about .about-team-layout {
  display: grid;
  gap: clamp(24px, 4vw, 42px);
  margin-top: clamp(26px, 4vw, 42px);
  align-items: start;
}

.page-about .about-team {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
}

.page-about .about-team__card {
  padding: 22px 20px 24px;
  border-radius: var(--yh-radius-m);
  background: var(--yh-paper-soft);
  border: 1px solid var(--yh-line);
  border-top-width: 3px;
  border-top-style: solid;
}

.page-about .about-team__card--orange { border-top-color: var(--yh-orange); }
.page-about .about-team__card--cyan { border-top-color: var(--yh-cyan); }
.page-about .about-team__card--gold { border-top-color: var(--yh-gold); }
.page-about .about-team__card--steel { border-top-color: var(--yh-steel); }

.page-about .about-team__num {
  display: block;
  font-size: 1.875rem;
  font-weight: 700;
  line-height: 1;
  color: var(--yh-ink);
}

.page-about .about-team__title {
  margin: 10px 0 8px;
  font-family: var(--yh-font-display);
  font-weight: 800;
  font-size: 1rem;
  color: var(--yh-ink);
}

.page-about .about-team__card p {
  font-size: 0.9375rem;
  line-height: 1.78;
  color: rgba(17, 24, 32, 0.76);
}

/* ---------- 生态 ---------- */
.page-about .about-eco {
  display: grid;
  gap: clamp(26px, 4vw, 44px);
  margin-top: clamp(26px, 4vw, 44px);
  align-items: center;
}

.page-about .about-eco__list {
  display: grid;
  gap: 18px;
}

.page-about .about-eco__item {
  position: relative;
  padding: 18px 18px 18px 22px;
  border-left: 2px solid rgba(52, 224, 208, 0.45);
  border-radius: 0 var(--yh-radius-s) var(--yh-radius-s) 0;
  background: rgba(244, 235, 221, 0.06);
  transition: border-left-color 200ms var(--yh-ease), background 200ms var(--yh-ease);
}

.page-about .about-eco__item:hover {
  border-left-color: var(--yh-cyan);
  background: rgba(244, 235, 221, 0.1);
}

.page-about .about-eco__idx {
  display: block;
  font-size: 0.6875rem;
  letter-spacing: 0.14em;
  color: var(--yh-cyan);
}

.page-about .about-eco__title {
  margin: 6px 0 8px;
  font-family: var(--yh-font-display);
  font-weight: 800;
  font-size: 1rem;
  color: var(--yh-paper);
}

.page-about .about-eco__item p {
  font-size: 0.9375rem;
  line-height: 1.8;
  color: var(--yh-on-dark);
}

/* ---------- 荣誉 ---------- */
.page-about .about-honors {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
  margin-top: clamp(26px, 4vw, 40px);
}

.page-about .about-honor {
  position: relative;
  padding: 22px 20px 24px;
  border-radius: var(--yh-radius-m);
  background: var(--yh-paper-soft);
  border: 1px solid var(--yh-line);
}

.page-about .about-honor--gold {
  background: linear-gradient(150deg, rgba(217, 164, 65, 0.22) 0%, var(--yh-paper-soft) 70%);
  border-color: rgba(217, 164, 65, 0.55);
}

.page-about .about-honor--cyan {
  background: linear-gradient(150deg, rgba(52, 224, 208, 0.18) 0%, var(--yh-paper-soft) 72%);
  border-color: rgba(52, 224, 208, 0.5);
}

.page-about .about-honor__num {
  display: block;
  font-size: 1.625rem;
  font-weight: 700;
  line-height: 1.1;
  color: var(--yh-ink);
}

.page-about .about-honor__tag {
  display: inline-block;
  padding: 3px 8px;
  border-radius: 4px;
  font-size: 0.75rem;
  letter-spacing: 0.1em;
  color: var(--yh-black);
  background: var(--yh-gold);
}

.page-about .about-honor__title {
  margin: 12px 0 8px;
  font-family: var(--yh-font-display);
  font-weight: 800;
  font-size: 0.9375rem;
  line-height: 1.5;
  color: var(--yh-ink);
}

.page-about .about-honor p {
  font-size: 0.875rem;
  line-height: 1.78;
  color: rgba(17, 24, 32, 0.74);
}

/* ---------- 结尾引导 ---------- */
.page-about .about-cta {
  display: grid;
  gap: clamp(22px, 3vw, 30px);
  padding: clamp(28px, 5vw, 56px);
  border-radius: var(--yh-radius-l);
  background:
    radial-gradient(circle at 92% 6%, rgba(255, 255, 255, 0.42), transparent 46%),
    linear-gradient(132deg, var(--yh-orange) 0%, #ff8a4c 52%, var(--yh-gold) 100%);
  color: var(--yh-black);
  box-shadow: var(--yh-shadow);
}

.page-about .about-cta__label {
  display: block;
  font-size: 0.6875rem;
  letter-spacing: 0.16em;
  color: rgba(17, 24, 32, 0.7);
}

.page-about .about-cta__title {
  margin: 10px 0 12px;
  font-family: var(--yh-font-display);
  font-weight: 800;
  font-size: clamp(1.4rem, 3vw, 2.15rem);
  line-height: 1.24;
  letter-spacing: -0.01em;
  color: var(--yh-black);
  max-width: 22ch;
}

.page-about .about-cta__text {
  font-size: 0.9375rem;
  line-height: 1.8;
  color: rgba(17, 24, 32, 0.82);
  max-width: 52ch;
}

.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  align-content: start;
}

.page-about .about-cta__btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 46px;
  padding: 12px 22px;
  border-radius: 999px;
  font-family: var(--yh-font-body);
  font-size: 0.9375rem;
  font-weight: 600;
  text-decoration: none;
  transition: transform 180ms var(--yh-ease), background 180ms var(--yh-ease), color 180ms var(--yh-ease);
}

.page-about .about-cta__btn--solid {
  background: var(--yh-ink);
  color: var(--yh-paper);
  border: 1px solid var(--yh-ink);
}

.page-about .about-cta__btn--line {
  background: transparent;
  color: var(--yh-black);
  border: 1px solid rgba(17, 24, 32, 0.55);
}

.page-about .about-cta__btn:hover,
.page-about .about-cta__btn:focus-visible {
  transform: translateY(-2px);
}

.page-about .about-cta__btn--line:hover,
.page-about .about-cta__btn--line:focus-visible {
  background: rgba(17, 24, 32, 0.1);
}

.page-about .about-cta__btn:focus-visible {
  outline: 2px solid var(--yh-ink);
  outline-offset: 3px;
}

/* ---------- 响应式 ---------- */
@media (min-width: 640px) {
  .page-about .about-fact__num {
    font-size: 1.5rem;
  }

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

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.45fr) minmax(0, 1fr);
    gap: clamp(36px, 5vw, 72px);
  }

  .page-about .about-fact:nth-child(even) {
    transform: translateY(14px);
  }

  .page-about .about-hero__facts {
    padding-bottom: 14px;
  }

  .page-about .about-history {
    grid-template-columns: minmax(0, 1.2fr) minmax(0, 1fr);
    align-items: start;
  }

  .page-about .about-team-layout {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, 1fr);
  }

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

  .page-about .about-eco {
    grid-template-columns: minmax(0, 1.1fr) minmax(0, 1fr);
  }

  .page-about .about-cta {
    grid-template-columns: minmax(0, 1.6fr) minmax(0, 1fr);
    align-items: center;
  }
}

@media (min-width: 1080px) {
  .page-about .about-honors {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .about-honor__num {
    font-size: 1.5rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-principle,
  .page-about .about-eco__item,
  .page-about .about-cta__btn,
  .page-about .about-crumbs a.yh-crumbs__item {
    transition: none;
  }

  .page-about .about-cta__btn:hover,
  .page-about .about-cta__btn:focus-visible {
    transform: none;
  }
}
<<<END>>>