.page-about {
  --about-card: #FBF7ED;
  --about-line: rgba(154, 158, 166, .38);
  --about-gold-line: rgba(201, 162, 74, .55);
  --about-ink-soft: rgba(245, 240, 229, .78);
  background: var(--paper);
  color: var(--ink);
  font-family: var(--sans);
  overflow-x: hidden;
}

.page-about .about-crumb-wrap {
  padding-top: clamp(14px, 2.4vw, 22px);
}

.page-about a {
  color: inherit;
}

.page-about h1,
.page-about h2,
.page-about h3 {
  font-family: var(--serif);
  font-weight: 600;
  letter-spacing: .07em;
  margin: 0;
}

/* ---------- 首屏框景 ---------- */
.page-about .about-hero {
  position: relative;
  background: var(--ink);
  color: var(--paper);
  padding-block: clamp(18px, 3.4vw, 28px) clamp(28px, 5vw, 56px);
}

.page-about .about-hero__frame {
  position: relative;
  border: 1px solid var(--about-gold-line);
  padding: clamp(22px, 4.6vw, 48px) clamp(18px, 4vw, 46px);
  background: linear-gradient(180deg, rgba(245, 240, 229, .06), rgba(245, 240, 229, 0) 62%);
}

.page-about .about-hero__frame::before,
.page-about .about-hero__frame::after {
  content: "";
  position: absolute;
  width: 18px;
  height: 18px;
  border: 1px solid var(--gold);
  opacity: .9;
}

.page-about .about-hero__frame::before {
  top: -1px;
  left: -1px;
  border-right: 0;
  border-bottom: 0;
}

.page-about .about-hero__frame::after {
  right: -1px;
  bottom: -1px;
  border-top: 0;
  border-left: 0;
}

.page-about .about-hero .eyebrow {
  color: var(--gold-lt);
}

.page-about .about-hero h1 {
  font-size: clamp(26px, 5vw, 46px);
  line-height: 1.38;
  margin: .55em 0 .7em;
  max-width: 20ch;
  color: var(--paper);
}

.page-about .about-hero__lede {
  margin: 0;
  max-width: 36em;
  font-size: 16px;
  line-height: 1.9;
  color: var(--about-ink-soft);
}

.page-about .hero-marks {
  list-style: none;
  margin: clamp(20px, 3.4vw, 30px) 0 0;
  padding: clamp(14px, 2.4vw, 18px) 0 0;
  display: grid;
  gap: 12px;
  border-top: 1px solid rgba(201, 162, 74, .3);
}

.page-about .hero-marks li {
  display: flex;
  align-items: baseline;
  gap: 10px;
  font-size: 13px;
  line-height: 1.6;
  color: rgba(245, 240, 229, .72);
}

.page-about .hero-marks .mono {
  color: var(--gold-lt);
  font-size: clamp(18px, 2.4vw, 22px);
  letter-spacing: .04em;
  flex: none;
}

@media (min-width: 620px) {
  .page-about .hero-marks {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 18px;
  }
  .page-about .hero-marks li {
    align-items: flex-start;
    flex-direction: column;
    gap: 4px;
  }
}

/* ---------- 章节骨架 ---------- */
.page-about .about-section {
  padding-block: clamp(34px, 6vw, 68px);
}

.page-about .about-section + .about-section {
  border-top: 1px solid var(--about-line);
}

.page-about .about-head {
  max-width: 42em;
  margin-bottom: clamp(22px, 3.6vw, 34px);
}

.page-about .about-head h2 {
  font-size: clamp(22px, 3.6vw, 33px);
  line-height: 1.42;
  margin: 0 0 12px;
}

.page-about .about-head__lede {
  margin: 0;
  font-size: 15px;
  line-height: 1.9;
  color: var(--graphite);
}

/* ---------- 场景 ---------- */
.page-about .scenes {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 14px;
}

.page-about .scenes__item {
  background: var(--about-card);
  border: 1px solid var(--about-line);
  border-top: 2px solid var(--gold);
  padding: 20px 18px 22px;
}

.page-about .scenes__item h3 {
  font-size: 17px;
  line-height: 1.5;
  margin: 10px 0 10px;
}

.page-about .scenes__item p {
  margin: 0;
  font-size: 14px;
  line-height: 1.88;
  color: var(--graphite);
}

.page-about .scenes__link {
  margin-top: 14px !important;
}

.page-about .scenes__link a,
.page-about .scale-note a,
.page-about .feedback__note a {
  color: var(--ink);
  text-decoration: none;
  border-bottom: 1px solid var(--gold);
  padding-bottom: 1px;
  transition: color .14s var(--ease), border-color .14s var(--ease);
}

.page-about .scenes__link a:hover,
.page-about .scale-note a:hover,
.page-about .feedback__note a:hover {
  color: var(--cinnabar);
  border-bottom-color: var(--cinnabar);
}

.page-about .scenes__link a:focus-visible,
.page-about .scale-note a:focus-visible,
.page-about .feedback__note a:focus-visible,
.page-about .btn:focus-visible,
.page-about .copy-btn:focus-visible {
  outline: 2px solid var(--gold);
  outline-offset: 3px;
}

@media (min-width: 720px) {
  .page-about .scenes {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 18px;
  }
}

.page-about .why-note {
  margin-top: clamp(18px, 3vw, 26px);
  max-width: 34em;
}

/* ---------- 沿革时间线 ---------- */
.page-about .chronicle {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 22px;
}

.page-about .chronicle__item {
  position: relative;
  display: grid;
  gap: 10px;
}

.page-about .chronicle__year {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 14px;
  color: var(--graphite);
}

.page-about .chronicle__year .mono {
  font-size: 15px;
  letter-spacing: .08em;
}

.page-about .chronicle__dot {
  width: 9px;
  height: 9px;
  background: var(--gold-lt);
  box-shadow: 0 0 0 1px rgba(201, 162, 74, .55);
  flex: none;
}

.page-about .chronicle__item--current .chronicle__dot {
  background: var(--cinnabar);
  box-shadow: 0 0 0 1px rgba(178, 58, 44, .5);
}

.page-about .chronicle__item--current .chronicle__year .mono {
  color: var(--cinnabar);
}

.page-about .chronicle__card {
  position: relative;
  background: var(--about-card);
  border: 1px solid var(--about-line);
  padding: 18px 18px 20px;
  transition: transform .16s var(--ease), box-shadow .16s var(--ease);
}

.page-about .chronicle__card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  height: 2px;
  width: 34%;
  background: var(--gold);
  transition: width .18s var(--ease);
}

.page-about .chronicle__card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow);
}

.page-about .chronicle__card:hover::before {
  width: 100%;
}

.page-about .chronicle__phase {
  margin: 0 0 8px;
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--gold);
  text-transform: uppercase;
}

.page-about .chronicle__card h3 {
  font-size: 18px;
  line-height: 1.5;
  margin: 0 0 10px;
}

.page-about .chronicle__card p {
  margin: 0;
  font-size: 14px;
  line-height: 1.88;
  color: var(--graphite);
}

.page-about .chronicle__gain {
  margin-top: 12px !important;
  padding-left: 12px;
  border-left: 2px solid var(--gold-lt);
  color: var(--ink) !important;
  font-size: 13.5px !important;
}

@media (min-width: 800px) {
  .page-about .chronicle__item {
    grid-template-columns: 118px minmax(0, 1fr);
    gap: 32px;
  }

  .page-about .chronicle__item::before {
    content: "";
    position: absolute;
    top: 6px;
    bottom: -22px;
    left: 118px;
    width: 1px;
    background: repeating-linear-gradient(to bottom, var(--rule) 0 5px, transparent 5px 11px);
    opacity: .5;
  }

  .page-about .chronicle__item:last-child::before {
    bottom: 40%;
  }

  .page-about .chronicle__year {
    justify-content: flex-end;
    align-self: start;
    padding-top: 20px;
    flex-direction: row-reverse;
  }
}

.page-about .chronicle-figure {
  margin: clamp(26px, 4vw, 40px) 0 0;
  max-width: 520px;
  margin-left: auto;
}

.page-about .chronicle-figure img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
  border: 1px solid var(--about-line);
}

.page-about .chronicle-figure figcaption {
  margin-top: 10px;
  font-size: 12.5px;
  line-height: 1.8;
  color: var(--graphite);
  text-align: right;
}

/* ---------- 三组分工 ---------- */
.page-about .roles {
  display: grid;
  gap: 16px;
}

.page-about .role {
  background: var(--about-card);
  border: 1px solid var(--about-line);
  border-left: 2px solid var(--gold);
  padding: 22px 18px 24px;
  transition: border-left-color .16s var(--ease), transform .16s var(--ease);
}

.page-about .role:hover {
  border-left-color: var(--cinnabar);
  transform: translateY(-2px);
}

.page-about .role__group {
  margin: 0 0 10px;
  font-size: 12px;
  letter-spacing: .12em;
  color: var(--gold);
}

.page-about .role h3 {
  font-size: 19px;
  line-height: 1.4;
  margin: 0 0 10px;
}

.page-about .role__lede {
  margin: 0 0 14px;
  font-size: 14px;
  line-height: 1.88;
  color: var(--graphite);
}

.page-about .role__list {
  list-style: none;
  margin: 0;
  padding: 14px 0 0;
  border-top: 1px dashed var(--about-line);
  display: grid;
  gap: 8px;
}

.page-about .role__list li {
  position: relative;
  padding-left: 15px;
  font-size: 13px;
  line-height: 1.75;
  color: var(--graphite);
}

.page-about .role__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: .62em;
  width: 6px;
  height: 6px;
  background: var(--gold-lt);
  transform: rotate(45deg);
}

@media (min-width: 780px) {
  .page-about .roles {
    grid-template-columns: 1fr 1.08fr 1fr;
    gap: 20px;
    align-items: start;
  }

  .page-about .role--raised {
    margin-top: -20px;
    padding-bottom: 34px;
    background: #FFFCF4;
  }
}

/* ---------- 四道工序 ---------- */
.page-about .proof-media {
  margin: 0 0 clamp(24px, 4vw, 36px);
}

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

.page-about .stages {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 16px;
  counter-reset: stage;
}

.page-about .stage {
  position: relative;
  background: var(--about-card);
  border: 1px solid var(--about-line);
  border-top: 2px solid var(--gold);
  padding: 18px 16px 20px;
}

.page-about .stage h3 {
  font-size: 17px;
  line-height: 1.45;
  margin: 10px 0 8px;
}

.page-about .stage p {
  margin: 0;
  font-size: 13.5px;
  line-height: 1.85;
  color: var(--graphite);
}

.page-about .stage__out {
  margin-top: 12px !important;
  padding-top: 10px;
  border-top: 1px dashed var(--about-line);
  font-size: 12.5px !important;
  color: var(--ink) !important;
}

.page-about .stage__out .mono {
  display: inline-block;
  margin-right: 8px;
  padding: 1px 6px;
  background: var(--paper-2);
  color: var(--graphite);
  font-size: 11px;
  letter-spacing: .1em;
}

@media (min-width: 900px) {
  .page-about .stages {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 28px;
  }

  .page-about .stage::after {
    content: "→";
    position: absolute;
    top: 26px;
    right: -21px;
    font-family: var(--mono);
    font-size: 14px;
    color: var(--rule);
    opacity: .8;
  }

  .page-about .stage:last-child::after {
    content: none;
  }
}

.page-about .proof-note {
  margin-top: clamp(18px, 3vw, 26px);
  max-width: 36em;
}

/* ---------- 规模 ---------- */
.page-about .scale-grid {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px;
}

.page-about .scale-cell {
  background: var(--paper-2);
  border: 1px solid var(--about-line);
  padding: 18px 14px 16px;
  display: flex;
  flex-direction: column;
  gap: 6px;
  transition: background .16s var(--ease), border-color .16s var(--ease);
}

.page-about .scale-cell:hover {
  background: #EFE7D6;
  border-color: var(--gold);
}

.page-about .scale-num {
  font-size: clamp(28px, 5.6vw, 40px);
  line-height: 1;
  letter-spacing: .02em;
  color: var(--ink);
}

.page-about .scale-unit {
  font-size: .48em;
  margin-left: 3px;
  color: var(--graphite);
}

.page-about .scale-label {
  font-size: 12.5px;
  letter-spacing: .04em;
  color: var(--graphite);
}

@media (min-width: 720px) {
  .page-about .scale-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 14px;
  }
}

.page-about .scale-note {
  margin: clamp(18px, 3vw, 26px) 0 0;
  max-width: 40em;
  font-size: 14px;
  line-height: 1.9;
  color: var(--graphite);
}

/* ---------- 反馈 ---------- */
.page-about .about-section--last {
  padding-bottom: clamp(40px, 7vw, 80px);
}

.page-about .feedback-figure {
  margin: 0 0 clamp(24px, 4vw, 36px);
}

.page-about .feedback-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: clamp(140px, 26vw, 220px);
  object-fit: cover;
  border: 1px solid var(--about-line);
}

.page-about .feedback {
  max-width: 720px;
  background: var(--about-card);
  border: 1px solid var(--about-line);
  border-top: 2px solid var(--gold);
  padding: clamp(22px, 3.6vw, 34px) clamp(18px, 3.4vw, 32px) clamp(24px, 4vw, 36px);
}

.page-about .feedback h2 {
  font-size: clamp(20px, 3.2vw, 28px);
  line-height: 1.45;
  margin: 0 0 14px;
}

.page-about .feedback > p {
  margin: 0 0 16px;
  font-size: 14.5px;
  line-height: 1.9;
  color: var(--graphite);
}

.page-about .feedback__list {
  list-style: none;
  margin: 0 0 22px;
  padding: 0;
  display: grid;
  gap: 9px;
}

.page-about .feedback__list li {
  position: relative;
  padding-left: 16px;
  font-size: 13.5px;
  line-height: 1.8;
  color: var(--graphite);
}

.page-about .feedback__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: .66em;
  width: 7px;
  height: 7px;
  background: var(--gold);
  transform: rotate(45deg);
}

.page-about .feedback__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

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

.page-about .feedback__note {
  margin: 18px 0 0;
  padding-top: 14px;
  border-top: 1px dashed var(--about-line);
  font-size: 12.5px;
  line-height: 1.85;
  color: var(--graphite);
}

/* ---------- 动效降级 ---------- */
@media (prefers-reduced-motion: reduce) {
  .page-about .chronicle__card,
  .page-about .chronicle__card::before,
  .page-about .role,
  .page-about .scale-cell,
  .page-about .scenes__link a {
    transition: none;
  }
  .page-about .chronicle__card:hover,
  .page-about .role:hover {
    transform: none;
  }
}
<<<END>>>