.page-about {
  --about-rule: rgba(29, 62, 107, 0.16);
  --about-rule-soft: rgba(29, 62, 107, 0.09);
  --about-text-2: #36495f;
  display: block;
  background: var(--white);
  color: var(--ink);
}

.page-about a {
  color: var(--line);
}

.page-about a:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 2px;
}

/* ---------- 面包屑 ---------- */
.page-about .about-crumb {
  display: flex;
  align-items: center;
  gap: var(--sp-2);
  padding-top: var(--sp-4);
  font-size: 14px;
  color: var(--slate);
}

.page-about .about-crumb a {
  color: var(--slate);
  text-decoration: none;
}

.page-about .about-crumb a:hover {
  color: var(--line);
  text-decoration: underline;
}

.page-about .about-crumb [aria-current="page"] {
  color: var(--ink);
  font-weight: 700;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding: var(--sp-4) 0 var(--sp-5);
  overflow: hidden;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(to right, var(--about-rule-soft) 1px, transparent 1px),
    linear-gradient(to bottom, var(--about-rule-soft) 1px, transparent 1px);
  background-size: 48px 48px;
  -webkit-mask-image: linear-gradient(180deg, #000 0%, transparent 72%);
  mask-image: linear-gradient(180deg, #000 0%, transparent 72%);
  pointer-events: none;
}

.page-about .about-hero-grid {
  position: relative;
  z-index: 1;
  display: grid;
  gap: var(--sp-4);
}

.page-about .about-hero-copy h1 {
  margin: var(--sp-2) 0 0;
  font-size: 30px;
  line-height: 1.22;
  font-weight: 900;
  letter-spacing: 0.05em;
  color: var(--navy);
}

.page-about .about-lede {
  margin: var(--sp-3) 0 0;
  font-size: 16px;
  line-height: 1.78;
  color: var(--about-text-2);
  max-width: 62ch;
}

.page-about .about-facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin-top: var(--sp-4);
  background: var(--about-rule);
  border: 1px solid var(--about-rule);
}

.page-about .about-fact {
  background: var(--white);
  padding: var(--sp-3);
}

.page-about .about-fact-num {
  display: block;
  font-family: var(--font-num);
  font-size: 26px;
  font-weight: 700;
  line-height: 1.05;
  letter-spacing: 0.02em;
  color: var(--navy);
}

.page-about .about-fact-label {
  display: block;
  margin-top: 6px;
  font-size: 13px;
  line-height: 1.5;
  color: var(--slate);
}

.page-about .about-hero-media {
  position: relative;
}

.page-about .about-hero-media img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 14 / 9;
  object-fit: cover;
  background: var(--navy);
  border: 1px solid var(--about-rule);
}

.page-about .about-hero-media::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -1px;
  width: 64px;
  height: 3px;
  background: var(--gold);
}

/* ---------- 双栏外壳 ---------- */
.page-about .about-shell {
  padding-bottom: var(--sp-5);
}

.page-about .about-index {
  display: none;
}

.page-about .about-index-title {
  margin: 0 0 var(--sp-3);
  font-family: var(--font-num);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.18em;
  color: var(--slate);
  text-transform: uppercase;
}

.page-about .about-index-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 2px;
  border-left: 2px solid var(--about-rule);
}

.page-about .about-index-link {
  display: flex;
  align-items: baseline;
  gap: var(--sp-2);
  padding: 7px 10px;
  margin-left: -2px;
  border-left: 2px solid transparent;
  font-size: 14px;
  color: var(--slate);
  text-decoration: none;
  transition: color 0.2s var(--ease), background 0.2s var(--ease), border-color 0.2s var(--ease);
}

.page-about .about-index-link .idx {
  font-family: var(--font-num);
  font-weight: 700;
  color: var(--line);
  opacity: 0.45;
}

.page-about .about-index-link:hover,
.page-about .about-index-link:focus-visible {
  color: var(--navy);
  background: var(--mist);
  border-left-color: var(--gold);
}

.page-about .about-index-link.is-current {
  color: var(--navy);
  font-weight: 700;
  background: var(--mist);
  border-left-color: var(--gold);
}

.page-about .about-index-link.is-current .idx {
  opacity: 1;
  color: var(--gold);
}

/* ---------- 章节 ---------- */
.page-about .about-sec {
  padding: var(--sp-5) 0;
  border-top: 1px solid var(--about-rule);
}

.page-about .about-main > .about-sec:first-child {
  border-top: none;
  padding-top: 0;
}

.page-about .about-sec-head {
  display: flex;
  align-items: baseline;
  gap: var(--sp-3);
  margin-bottom: var(--sp-3);
}

.page-about .about-sec-num {
  flex: none;
  font-family: var(--font-num);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.16em;
  color: var(--cyan);
}

.page-about .about-sec-title {
  margin: 0;
  font-size: 21px;
  line-height: 1.32;
  font-weight: 900;
  letter-spacing: 0.04em;
  color: var(--navy);
}

.page-about .about-sec-lede {
  margin: 0 0 var(--sp-4);
  font-size: 16px;
  line-height: 1.78;
  color: var(--about-text-2);
  max-width: 66ch;
}

.page-about .about-prose p {
  margin: 0 0 var(--sp-3);
  font-size: 16px;
  line-height: 1.8;
  color: var(--about-text-2);
  max-width: 68ch;
}

.page-about .about-prose p:last-child {
  margin-bottom: 0;
}

/* ---------- 引文 ---------- */
.page-about .about-quote {
  margin: var(--sp-4) 0 0;
  padding: var(--sp-3) var(--sp-4);
  border-left: 3px solid var(--gold);
  background: var(--mist);
  font-family: var(--font-serif);
  font-size: 16px;
  line-height: 1.85;
  color: var(--navy);
}

.page-about .about-quote cite {
  display: block;
  margin-top: var(--sp-2);
  font-family: var(--font-sans);
  font-style: normal;
  font-size: 13px;
  letter-spacing: 0.04em;
  color: var(--slate);
}

/* ---------- 团队矩阵 ---------- */
.page-about .about-team-figure {
  margin: 0 0 var(--sp-4);
}

.page-about .about-team-figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 2 / 1;
  object-fit: cover;
  background: var(--navy-2);
  border: 1px solid var(--about-rule);
}

.page-about .about-team-figure figcaption {
  margin-top: var(--sp-2);
  font-size: 13px;
  line-height: 1.6;
  color: var(--slate);
}

.page-about .about-team {
  display: grid;
  gap: 1px;
  background: var(--about-rule);
  border: 1px solid var(--about-rule);
}

.page-about .about-team-cell {
  background: var(--white);
  padding: var(--sp-4) var(--sp-3);
  border-top: 2px solid transparent;
  transition: border-color 0.2s var(--ease), background 0.2s var(--ease);
}

.page-about .about-team-cell:hover {
  border-top-color: var(--gold);
  background: var(--mist);
}

.page-about .about-team-num {
  display: block;
  font-family: var(--font-num);
  font-size: 32px;
  font-weight: 700;
  line-height: 1;
  color: var(--navy);
  letter-spacing: 0.01em;
}

.page-about .about-team-num small {
  font-family: var(--font-sans);
  font-size: 12px;
  font-weight: 400;
  letter-spacing: 0.02em;
  color: var(--slate);
  margin-left: 4px;
}

.page-about .about-team-name {
  margin: var(--sp-3) 0 0;
  font-size: 16px;
  font-weight: 900;
  letter-spacing: 0.04em;
  color: var(--navy);
}

.page-about .about-team-desc {
  margin: var(--sp-2) 0 0;
  font-size: 14px;
  line-height: 1.72;
  color: var(--about-text-2);
}

/* ---------- 内容工序 ---------- */
.page-about .about-std-grid {
  display: grid;
  gap: var(--sp-3);
}

.page-about .about-std {
  padding: var(--sp-4);
  background: var(--white);
  border: 1px solid var(--about-rule);
  border-top: 3px solid var(--line);
}

.page-about .about-std--alt {
  border-top-color: var(--gold);
}

.page-about .about-std h3 {
  margin: var(--sp-3) 0 var(--sp-2);
  font-size: 18px;
  font-weight: 900;
  letter-spacing: 0.04em;
  color: var(--navy);
}

.page-about .about-std ul {
  margin: 0;
  padding-left: 18px;
}

.page-about .about-std li {
  margin-bottom: 8px;
  font-size: 15px;
  line-height: 1.72;
  color: var(--about-text-2);
}

.page-about .about-std li:last-child {
  margin-bottom: 0;
}

.page-about .about-std li strong {
  color: var(--navy);
  font-weight: 700;
}

.page-about .about-std-note {
  margin: var(--sp-4) 0 0;
  padding: var(--sp-3) 0 0;
  border-top: 1px solid var(--about-rule-soft);
  font-size: 14px;
  line-height: 1.75;
  color: var(--slate);
}

.page-about .about-std-note a {
  color: var(--line);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.page-about .about-std-note a:hover {
  color: var(--gold);
}

/* ---------- 时间轴 ---------- */
.page-about .about-tl-wrap {
  display: grid;
  gap: var(--sp-4);
}

.page-about .about-tl {
  position: relative;
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .about-tl::before {
  content: "";
  position: absolute;
  left: 11px;
  top: 8px;
  bottom: 8px;
  width: 2px;
  background: linear-gradient(180deg, var(--line) 0%, rgba(29, 62, 107, 0.12) 100%);
}

.page-about .about-tl-item {
  position: relative;
  padding-left: 42px;
  padding-bottom: var(--sp-4);
}

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

.page-about .about-tl-item::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 4px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--white);
  border: 2px solid var(--gold);
  box-sizing: border-box;
  transition: background 0.2s var(--ease), box-shadow 0.2s var(--ease);
}

.page-about .about-tl-item:hover::before {
  background: var(--gold);
  box-shadow: 0 0 0 4px rgba(227, 178, 75, 0.18);
}

.page-about .about-tl-item.is-major::before {
  background: var(--gold);
  box-shadow: 0 0 0 4px rgba(227, 178, 75, 0.16);
}

.page-about .about-tl-stage {
  display: block;
  font-family: var(--font-num);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.14em;
  color: var(--line);
  opacity: 0.72;
  margin-bottom: 6px;
}

.page-about .about-tl-title {
  margin: 0 0 6px;
  font-size: 17px;
  font-weight: 900;
  letter-spacing: 0.03em;
  color: var(--navy);
}

.page-about .about-tl-text {
  margin: 0;
  font-size: 15px;
  line-height: 1.75;
  color: var(--about-text-2);
  max-width: 52ch;
}

.page-about .about-tl-figure {
  margin: 0;
}

.page-about .about-tl-figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 4 / 3;
  object-fit: cover;
  background: var(--navy-2);
  border: 1px solid var(--about-rule);
}

.page-about .about-tl-figure figcaption {
  margin-top: var(--sp-2);
  font-size: 13px;
  line-height: 1.6;
  color: var(--slate);
}

/* ---------- 会员步骤 ---------- */
.page-about .about-steps {
  display: grid;
  gap: var(--sp-3);
}

.page-about .about-step {
  position: relative;
  padding: var(--sp-4);
  background: var(--mist);
  border: 1px solid var(--about-rule-soft);
}

.page-about .about-step--key {
  background: var(--navy);
  border-color: var(--navy);
  color: var(--mist);
}

.page-about .about-step-num {
  display: block;
  font-family: var(--font-num);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.16em;
  color: var(--gold);
}

.page-about .about-step-title {
  margin: var(--sp-2) 0 var(--sp-2);
  font-size: 17px;
  font-weight: 900;
  letter-spacing: 0.04em;
  color: var(--navy);
}

.page-about .about-step-text {
  margin: 0;
  font-size: 15px;
  line-height: 1.75;
  color: var(--about-text-2);
}

.page-about .about-step--key .about-step-title {
  color: var(--white);
}

.page-about .about-step--key .about-step-text {
  color: rgba(242, 245, 249, 0.82);
}

/* ---------- 服务与合规 ---------- */
.page-about .about-compliance {
  display: grid;
  gap: var(--sp-4);
  padding: var(--sp-4);
  background: var(--navy);
  border-radius: var(--radius);
  color: var(--mist);
}

.page-about .about-compliance-item {
  padding-top: var(--sp-3);
  border-top: 1px solid var(--line-on-dark);
}

.page-about .about-compliance-item:first-child {
  padding-top: 0;
  border-top: none;
}

.page-about .about-compliance-key {
  display: block;
  font-family: var(--font-num);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.18em;
  color: var(--gold-2);
  margin-bottom: var(--sp-2);
}

.page-about .about-compliance-val {
  margin: 0;
  font-size: 15px;
  line-height: 1.75;
  color: rgba(242, 245, 249, 0.84);
}

.page-about .about-compliance-val a {
  color: var(--gold-2);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.page-about .about-compliance-val a:hover {
  color: var(--white);
}

.page-about .about-outro {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: var(--sp-3);
  margin-top: var(--sp-4);
  padding-top: var(--sp-3);
  border-top: 1px solid var(--about-rule-soft);
}

.page-about .about-outro p {
  margin: 0;
  font-size: 15px;
  line-height: 1.75;
  color: var(--slate);
  max-width: 62ch;
}

.page-about .about-outro a:not(.btn) {
  color: var(--line);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.page-about .about-outro a:not(.btn):hover {
  color: var(--gold);
}

/* ---------- 平板 ---------- */
@media (min-width: 720px) {
  .page-about .about-hero-copy h1 {
    font-size: 40px;
    letter-spacing: 0.07em;
  }

  .page-about .about-lede {
    font-size: 17px;
  }

  .page-about .about-facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .about-fact-num {
    font-size: 30px;
  }

  .page-about .about-sec-title {
    font-size: 26px;
  }

  .page-about .about-outro {
    flex-direction: row;
    align-items: center;
    justify-content: space-between;
  }
}

@media (min-width: 860px) {
  .page-about .about-hero-grid {
    grid-template-columns: 7fr 5fr;
    gap: var(--sp-5);
    align-items: center;
  }

  .page-about .about-std-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: var(--sp-4);
  }

  .page-about .about-steps {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .about-compliance {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: var(--sp-4);
    padding: var(--sp-5);
  }

  .page-about .about-compliance-item {
    padding-top: 0;
    padding-left: var(--sp-3);
    border-top: none;
    border-left: 1px solid var(--line-on-dark);
  }

  .page-about .about-compliance-item:first-child {
    padding-left: 0;
    border-left: none;
  }
}

@media (min-width: 900px) {
  .page-about .about-tl-wrap {
    grid-template-columns: minmax(0, 1.4fr) minmax(0, 1fr);
    gap: var(--sp-5);
    align-items: start;
  }
}

@media (min-width: 1024px) {
  .page-about .about-shell {
    display: grid;
    grid-template-columns: 200px minmax(0, 1fr);
    gap: var(--sp-5);
    align-items: start;
  }

  .page-about .about-index {
    display: block;
    position: sticky;
    top: 96px;
  }

  .page-about .about-hero-copy h1 {
    font-size: 44px;
    letter-spacing: 0.09em;
  }

  .page-about .about-team {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-team-cell,
  .page-about .about-index-link,
  .page-about .about-tl-item::before {
    transition: none;
  }
}
<<<END>>>