.page-about {
  --about-rule: 1px dashed rgba(11, 31, 58, 0.28);
  --about-rule-solid: 1px solid rgba(11, 31, 58, 0.16);
  background: var(--sand);
  color: var(--ink);
  padding-bottom: 24px;
}

.page-about .breadcrumbs {
  padding: 18px 0 0;
}

/* ---------- 首屏：7 / 4 非对称 ---------- */
.page-about .about-hero {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 26px;
  padding: 18px 0 52px;
  border-bottom: var(--about-rule);
}

.page-about .about-hero__lead .page-title {
  margin: 10px 0 16px;
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(30px, 5.4vw, 52px);
  line-height: 1.12;
  letter-spacing: -0.02em;
  color: var(--navy);
  max-width: 16em;
}

.page-about .about-hero__lede {
  font-family: var(--font-body);
  font-size: 16.5px;
  line-height: 1.78;
  color: var(--ink);
  max-width: 42em;
  margin: 0;
}

.page-about .about-hero__stamp {
  background: var(--sand-2);
  padding: 20px 20px 18px;
  border: var(--about-rule-solid);
  box-shadow: var(--shadow-paper);
  position: relative;
}

.page-about .about-hero__stamp::before {
  content: "";
  position: absolute;
  inset: 8px 8px auto auto;
  width: 30px;
  height: 30px;
  border-top: 2px solid var(--orange);
  border-right: 2px solid var(--orange);
  opacity: 0.6;
}

.page-about .about-hero__stamp-title {
  margin: 10px 0 12px;
  font-family: var(--font-head);
  font-weight: 900;
  font-size: 15px;
  letter-spacing: 0.06em;
  color: var(--navy);
}

.page-about .about-hero__stamp-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 8px;
}

.page-about .about-hero__stamp-list li {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 10px;
  padding: 6px 0;
  border-bottom: var(--about-rule);
  font-family: var(--font-body);
  font-size: 14px;
  color: var(--ink);
}

.page-about .about-hero__stamp-list li:last-child { border-bottom: none; }

.page-about .about-hero__stamp-list .mono {
  color: var(--navy);
  font-weight: 700;
  font-size: 13.5px;
  white-space: nowrap;
}

/* ---------- 起点：年份刻度 + 档案卡 ---------- */
.page-about .about-origin {
  background:
    radial-gradient(circle at 12% 0%, rgba(92, 122, 138, 0.16), transparent 46%),
    var(--sand);
}

.page-about .about-origin__layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 22px;
}

.page-about .year-rail ol {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  gap: 8px;
  overflow-x: auto;
}

.page-about .year-rail__item {
  flex: 1 0 auto;
  min-width: 66px;
  border-top: 3px solid var(--slate);
  padding: 8px 4px 4px;
  font-family: var(--font-body);
  font-size: 12.5px;
  color: var(--slate);
  display: grid;
  gap: 2px;
}

.page-about .year-rail__item.is-active {
  border-top-color: var(--orange);
  color: var(--navy);
}

.page-about .year-rail__year {
  display: block;
  font-size: 13px;
  font-weight: 700;
  letter-spacing: -0.01em;
  color: var(--navy);
}

.page-about .year-rail__item.is-active .year-rail__year {
  color: var(--orange);
}

.page-about .about-origin__body {
  background: var(--paper);
  border: var(--about-rule-solid);
  padding: 22px 18px 24px;
  box-shadow: var(--shadow-paper);
}

.page-about .about-origin__title {
  margin: 8px 0 16px;
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(22px, 3.2vw, 30px);
  line-height: 1.25;
  letter-spacing: -0.01em;
  color: var(--navy);
}

.page-about .about-origin__figure {
  margin: 0 0 18px;
  border: var(--about-rule-solid);
  background: var(--sand-2);
  overflow: hidden;
}

.page-about .about-origin__figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  filter: saturate(0.88) contrast(0.96);
}

.page-about .about-origin__body p {
  font-family: var(--font-body);
  font-size: 15.5px;
  line-height: 1.78;
  margin: 0 0 14px;
  color: var(--ink);
}

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

/* ---------- 方法体系 ---------- */
.page-about .about-method {
  background: var(--sand-2);
  border-top: var(--about-rule-solid);
  border-bottom: var(--about-rule-solid);
}

.page-about .about-method__intro {
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.75;
  color: var(--slate);
  max-width: 34em;
  margin: 8px 0 0;
}

.page-about .method-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
  margin-top: 26px;
}

.page-about .method-card {
  background: var(--paper);
  border: var(--about-rule-solid);
  border-left: 5px solid var(--slate);
  box-shadow: var(--shadow-paper);
  padding: 0;
}

.page-about .method-card[open] {
  border-left-color: var(--orange);
}

.page-about .method-card summary {
  list-style: none;
  cursor: pointer;
  padding: 16px 18px 14px;
  display: flex;
  align-items: baseline;
  gap: 10px;
  position: relative;
}

.page-about .method-card summary::-webkit-details-marker,
.page-about .drawer summary::-webkit-details-marker { display: none; }

.page-about .method-card summary::after {
  content: "+";
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 18px;
  line-height: 1;
  color: var(--orange);
}

.page-about .method-card[open] summary::after { content: "−"; }

.page-about .method-card__num {
  font-size: 12px;
  color: var(--slate);
  letter-spacing: 0.04em;
}

.page-about .method-card__title {
  font-family: var(--font-head);
  font-weight: 900;
  font-size: 19px;
  letter-spacing: -0.01em;
  color: var(--navy);
}

.page-about .method-card__body {
  padding: 0 18px 18px;
  border-top: var(--about-rule);
  margin-top: 2px;
}

.page-about .method-card__body p {
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.76;
  margin: 12px 0 10px;
  color: var(--ink);
}

.page-about .method-card__body ul {
  list-style: none;
  padding: 0;
  margin: 0 0 10px;
  display: grid;
  gap: 6px;
}

.page-about .method-card__body ul li {
  font-family: var(--font-body);
  font-size: 14px;
  line-height: 1.6;
  padding-left: 16px;
  position: relative;
  color: var(--ink);
}

.page-about .method-card__body ul li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.62em;
  width: 8px;
  height: 1px;
  background: var(--moss);
}

.page-about .method-card__more {
  margin: 12px 0 0;
  font-family: var(--font-mono);
  font-size: 13px;
}

.page-about .method-card__more a {
  color: var(--clay);
  text-decoration: none;
  border-bottom: 1px dashed currentColor;
}

.page-about .method-card__more a:hover,
.page-about .method-card__more a:focus-visible {
  color: var(--orange);
}

/* ---------- 老用户栏目：索引侧栏 + 抽屉 ---------- */
.page-about .about-index {
  background: var(--sand);
}

.page-about .about-index__layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 22px;
  margin-top: 24px;
}

.page-about .about-index__intro {
  background: var(--navy);
  color: var(--sand);
  padding: 20px 18px;
  border-left: 5px solid var(--orange);
}

.page-about .about-index__intro p {
  font-family: var(--font-body);
  font-size: 14.5px;
  line-height: 1.78;
  margin: 0 0 14px;
  color: var(--sand);
}

.page-about .about-index__figure {
  margin: 0 0 14px;
  border: 1px solid rgba(242, 232, 213, 0.32);
  overflow: hidden;
  background: var(--navy-2);
}

.page-about .about-index__figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  opacity: 0.92;
}

.page-about .about-index__more {
  font-size: 13.5px;
  color: var(--sand-2);
  margin-bottom: 0;
}

.page-about .about-index__more a {
  color: var(--orange);
  text-decoration: none;
  border-bottom: 1px dashed currentColor;
}

.page-about .drawer-list {
  display: grid;
  gap: 10px;
  align-content: start;
}

.page-about .drawer {
  background: var(--paper);
  border: var(--about-rule-solid);
  border-left: 4px solid var(--slate);
}

.page-about .drawer[open] {
  border-left-color: var(--moss);
}

.page-about .drawer summary {
  list-style: none;
  cursor: pointer;
  padding: 12px 14px;
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: 10px;
}

.page-about .drawer__label {
  font-size: 12px;
  color: var(--slate);
  letter-spacing: 0.04em;
}

.page-about .drawer[open] .drawer__label { color: var(--moss); }

.page-about .drawer__name {
  font-family: var(--font-head);
  font-weight: 900;
  font-size: 16px;
  letter-spacing: -0.01em;
  color: var(--navy);
}

.page-about .drawer__count {
  font-size: 11.5px;
  color: var(--slate);
  white-space: nowrap;
}

.page-about .drawer__body {
  padding: 0 14px 14px;
  border-top: var(--about-rule);
}

.page-about .drawer__body ul {
  list-style: none;
  margin: 10px 0 0;
  padding: 0;
  display: grid;
  gap: 4px;
}

.page-about .drawer__body li {
  font-family: var(--font-body);
  font-size: 13.5px;
  line-height: 1.6;
  color: var(--ink);
  padding: 4px 0 4px 18px;
  position: relative;
  border-bottom: var(--about-rule);
}

.page-about .drawer__body li:last-child { border-bottom: none; }

.page-about .drawer__body li::before {
  content: "";
  position: absolute;
  left: 2px;
  top: 50%;
  width: 6px;
  height: 6px;
  transform: translateY(-50%) rotate(45deg);
  background: var(--slate);
}

/* ---------- 团队分工流程带 ---------- */
.page-about .about-team {
  background: var(--sand-2);
  border-top: var(--about-rule-solid);
  border-bottom: var(--about-rule-solid);
}

.page-about .team-flow {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
  margin-top: 26px;
}

.page-about .team-flow__lane {
  background: var(--paper);
  border-top: 3px solid var(--navy);
  padding: 16px 16px 18px;
  box-shadow: var(--shadow-paper);
}

.page-about .team-flow__lane:nth-child(2) { border-top-color: var(--slate); }
.page-about .team-flow__lane:nth-child(3) { border-top-color: var(--moss); }
.page-about .team-flow__lane:nth-child(4) { border-top-color: var(--clay); }

.page-about .team-flow__num {
  display: inline-block;
  font-size: 12px;
  color: var(--slate);
  letter-spacing: 0.04em;
  padding: 2px 8px;
  border: 1px dashed rgba(11, 31, 58, 0.28);
}

.page-about .team-flow__lane h3 {
  margin: 10px 0 8px;
  font-family: var(--font-head);
  font-weight: 900;
  font-size: 18px;
  letter-spacing: -0.01em;
  color: var(--navy);
}

.page-about .team-flow__lane p {
  font-family: var(--font-body);
  font-size: 14px;
  line-height: 1.72;
  margin: 0;
  color: var(--ink);
}

.page-about .team-flow__figure {
  margin: 20px 0 0;
  border: var(--about-rule-solid);
  background: var(--paper);
  padding: 10px;
}

.page-about .team-flow__figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  filter: saturate(0.9);
}

.page-about .team-flow__figure .img-caption {
  margin: 10px 2px 0;
  font-family: var(--font-body);
  font-size: 13px;
  line-height: 1.65;
  color: var(--slate);
}

.page-about .about-team__note {
  margin: 18px 0 0;
  font-family: var(--font-body);
  font-size: 14.5px;
  line-height: 1.78;
  color: var(--ink);
  padding-left: 14px;
  border-left: 3px solid var(--moss);
}

/* ---------- 发展节点 ---------- */
.page-about .about-milestones {
  background: var(--sand);
}

.page-about .milestone-chips {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 22px 0 18px;
}

.page-about .milestone-chips .chip {
  font-family: var(--font-mono);
  font-size: 12.5px;
  padding: 7px 12px;
  border: 1px solid rgba(11, 31, 58, 0.28);
  color: var(--navy);
  background: var(--paper);
  text-decoration: none;
  letter-spacing: 0.02em;
}

.page-about .milestone-chips .chip.is-active {
  background: var(--navy);
  color: var(--sand);
  border-color: var(--navy);
  border-bottom: 3px solid var(--orange);
  padding-bottom: 5px;
}

.page-about .milestone-chips .chip:hover,
.page-about .milestone-chips .chip:focus-visible {
  border-color: var(--orange);
  color: var(--orange);
}

.page-about .milestone-chips .chip.is-active:hover,
.page-about .milestone-chips .chip.is-active:focus-visible {
  color: var(--sand);
}

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

.page-about .milestone-item {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 0;
  background: var(--paper);
  border: var(--about-rule-solid);
  border-left: 5px solid var(--slate);
  padding: 16px 16px 18px;
}

.page-about .milestone-item:nth-child(2) { border-left-color: var(--moss); }
.page-about .milestone-item:nth-child(3) { border-left-color: var(--clay); }

.page-about .milestone-item__year {
  font-size: 20px;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--orange);
  margin-bottom: 6px;
}

.page-about .milestone-item__body h3 {
  margin: 0 0 8px;
  font-family: var(--font-head);
  font-weight: 900;
  font-size: 18px;
  letter-spacing: -0.01em;
  color: var(--navy);
}

.page-about .milestone-item__body p {
  font-family: var(--font-body);
  font-size: 14.5px;
  line-height: 1.75;
  margin: 0 0 10px;
  color: var(--ink);
}

.page-about .milestone-item__meta {
  margin: 0 !important;
}

.page-about .about-milestones__more {
  margin: 18px 0 0;
  font-family: var(--font-body);
  font-size: 14.5px;
  line-height: 1.75;
  color: var(--slate);
}

.page-about .about-milestones__more a {
  color: var(--clay);
  text-decoration: none;
  border-bottom: 1px dashed currentColor;
}

.page-about .about-milestones__more a:hover,
.page-about .about-milestones__more a:focus-visible {
  color: var(--orange);
}

/* ---------- CTA ---------- */
.page-about .about-cta {
  padding-bottom: 48px;
}

.page-about .about-cta__panel {
  position: relative;
  background: var(--navy);
  color: var(--sand);
  padding: 26px 20px 24px;
  border-top: 4px solid var(--orange);
  overflow: hidden;
}

.page-about .about-cta__panel::after {
  content: "";
  position: absolute;
  right: -40px;
  bottom: -40px;
  width: 200px;
  height: 200px;
  background:
    repeating-linear-gradient(45deg, rgba(242, 232, 213, 0.08) 0 2px, transparent 2px 12px);
  pointer-events: none;
}

.page-about .about-cta__panel .eyebrow {
  color: var(--orange);
}

.page-about .about-cta__panel h2 {
  margin: 8px 0 12px;
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(22px, 3.4vw, 30px);
  line-height: 1.22;
  letter-spacing: -0.01em;
  color: var(--paper);
  position: relative;
  z-index: 1;
}

.page-about .about-cta__panel > p {
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.78;
  margin: 0 0 18px;
  color: var(--sand);
  max-width: 44em;
  position: relative;
  z-index: 1;
}

.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 20px;
  position: relative;
  z-index: 1;
}

.page-about .about-cta__copy {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  padding-top: 16px;
  border-top: 1px dashed rgba(242, 232, 213, 0.3);
  position: relative;
  z-index: 1;
}

.page-about .about-cta__copy-label {
  font-family: var(--font-body);
  font-size: 13px;
  color: var(--slate);
  letter-spacing: 0.04em;
}

.page-about .about-cta__copy-value {
  font-size: 13.5px;
  color: var(--sand);
  word-break: break-all;
}

.page-about .about-cta__copy .copy-btn {
  background: transparent;
  color: var(--orange);
  border: 1px solid var(--orange);
  font-family: var(--font-mono);
  font-size: 12px;
  padding: 5px 10px;
  cursor: pointer;
  letter-spacing: 0.02em;
}

.page-about .about-cta__copy .copy-btn:hover,
.page-about .about-cta__copy .copy-btn:focus-visible {
  background: var(--orange);
  color: var(--navy);
}

.page-about .about-cta__copy .copy-btn[data-copied="true"] {
  background: var(--moss);
  border-color: var(--moss);
  color: var(--paper);
}

/* ---------- 响应式 ---------- */
@media (min-width: 640px) {
  .page-about .method-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .page-about .team-flow {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .page-about .milestone-item {
    grid-template-columns: 90px minmax(0, 1fr);
    gap: 0 18px;
    padding: 18px 18px 20px;
  }
  .page-about .milestone-item__year {
    margin: 0;
    padding-top: 2px;
    border-right: var(--about-rule);
    padding-right: 12px;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero {
    grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
    align-items: end;
    gap: 48px;
    padding: 24px 0 64px;
  }

  .page-about .about-hero__stamp {
    transform: translateY(-6px);
  }

  .page-about .about-origin__layout {
    grid-template-columns: 110px minmax(0, 1fr);
    gap: 36px;
  }

  .page-about .year-rail ol {
    flex-direction: column;
    overflow: visible;
    gap: 0;
  }

  .page-about .year-rail__item {
    border-top: none;
    border-left: 3px solid var(--slate);
    padding: 10px 0 14px 12px;
    min-width: 0;
    flex: none;
  }

  .page-about .year-rail__item.is-active {
    border-left-color: var(--orange);
  }

  .page-about .about-origin__body {
    padding: 30px 30px 32px;
  }

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

  .page-about .about-index__layout {
    grid-template-columns: minmax(0, 4fr) minmax(0, 7fr);
    gap: 32px;
  }

  .page-about .about-index__intro {
    padding: 26px 22px;
  }

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

  .page-about .about-cta__panel {
    padding: 34px 34px 30px;
  }
}

@media (min-width: 1100px) {
  .page-about .about-hero__stamp {
    padding: 24px 24px 22px;
  }
  .page-about .about-origin__body {
    padding: 34px 36px 36px;
  }
}
<<<PAGE_CSS_END>>>