.page-about {
  --about-rail: 300px;
  --about-gap: 44px;
  --about-accent-2: var(--coral);
  --about-accent-3: var(--amber);
  overflow-x: hidden;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding-block: 26px 56px;
  background:
    radial-gradient(540px 260px at 6% -12%, rgba(47, 227, 208, 0.10), transparent 70%),
    radial-gradient(440px 240px at 98% 8%, rgba(255, 107, 74, 0.07), transparent 72%);
}

.page-about .about-hero__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 30px;
  align-items: start;
}

.page-about .about-hero__copy .section-kicker {
  margin-bottom: 8px;
}

.page-about h1 {
  font-size: clamp(1.85rem, 5.2vw, 2.75rem);
  line-height: 1.16;
  font-weight: 900;
  letter-spacing: -0.02em;
  margin: 10px 0 18px;
  max-width: 24ch;
}

.page-about .about-hero .lead {
  max-width: 62ch;
  color: var(--ink);
  font-size: 1.0625rem;
  line-height: 1.75;
  margin: 0;
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin: 26px 0 0;
}

.page-about .about-hero__side {
  padding: 24px 24px 26px;
}

.page-about .about-facts {
  list-style: none;
  margin: 16px 0 0;
  padding: 0;
  display: grid;
  gap: 14px;
}

.page-about .about-facts li {
  display: grid;
  grid-template-columns: minmax(0, auto) minmax(0, 1fr);
  column-gap: 16px;
  align-items: baseline;
  padding-bottom: 13px;
  border-bottom: 1px solid var(--line);
}

.page-about .about-facts li:last-child {
  border-bottom: 0;
  padding-bottom: 0;
}

.page-about .about-facts__num {
  font-size: 1.125rem;
  font-weight: 500;
  color: var(--cyan);
  letter-spacing: -0.01em;
  white-space: nowrap;
}

.page-about .about-facts__text {
  font-size: 0.875rem;
  line-height: 1.7;
  color: var(--muted);
}

/* ---------- 章节骨架 ---------- */
.page-about .section {
  padding-block: 52px;
}

.page-about .section-head {
  margin-bottom: 28px;
}

.page-about .section-head::after {
  content: "";
  display: block;
  width: 64px;
  height: 2px;
  margin-top: 14px;
  background: linear-gradient(90deg, var(--cyan), rgba(47, 227, 208, 0));
}

.page-about .section-title {
  margin: 8px 0 0;
}

.page-about .divider-slant {
  margin-block: 8px 0;
}

/* ---------- 品牌起点：左时间轴 + 右正文 ---------- */
.page-about .about-origins__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 34px;
}

.page-about .tl-list {
  list-style: none;
  margin: 0;
  padding: 0;
  position: relative;
  display: grid;
  gap: 16px;
}

.page-about .tl-list::before {
  content: "";
  position: absolute;
  left: 7px;
  top: 22px;
  bottom: 22px;
  width: 1px;
  background: linear-gradient(180deg, var(--cyan) 0%, rgba(47, 227, 208, 0.22) 55%, rgba(255, 107, 74, 0.45) 100%);
}

.page-about .tl-node {
  position: relative;
  margin-left: 32px;
  padding: 12px 14px 14px;
  border: 1px solid var(--line-cyan);
  background: linear-gradient(135deg, var(--panel), var(--panel-deep));
  clip-path: polygon(0 0, calc(100% - 12px) 0, 100% 12px, 100% 100%, 12px 100%, 0 calc(100% - 12px));
  transition: border-color var(--dur) var(--ease), background-color var(--dur) var(--ease);
}

.page-about .tl-node::before {
  content: "";
  position: absolute;
  left: -32px;
  top: 16px;
  width: 15px;
  height: 15px;
  border-radius: 50%;
  background: var(--void);
  border: 2px solid var(--coral);
  transition: background-color var(--dur) var(--ease), box-shadow var(--dur) var(--ease),
    border-color var(--dur) var(--ease);
}

.page-about .tl-node:hover,
.page-about .tl-node:focus {
  border-color: var(--line-cyan-strong);
  background: linear-gradient(135deg, #132murky, #0d1830);
  background: linear-gradient(135deg, #122murky, #0d1830);
  background: linear-gradient(135deg, var(--panel), #0d1830);
  box-shadow: inset 0 0 0 1px rgba(47, 227, 208, 0.16);
}

.page-about .tl-node:focus-visible {
  outline: none;
  box-shadow: inset 0 0 0 1px var(--cyan);
}

.page-about .tl-node:hover::before,
.page-about .tl-node:focus::before {
  background: var(--coral);
  border-color: var(--coral);
  box-shadow: 0 0 0 4px rgba(255, 107, 74, 0.16);
}

.page-about .tl-ver {
  display: inline-block;
  font-size: 0.75rem;
  letter-spacing: 0.08em;
  color: var(--cyan);
  background: var(--cyan-wash);
  padding: 2px 7px;
  margin-bottom: 7px;
}

.page-about .tl-title {
  margin: 0;
  font-size: 0.9375rem;
  font-weight: 800;
  line-height: 1.5;
  letter-spacing: -0.01em;
}

.page-about .tl-more {
  margin: 0;
  max-height: 0;
  overflow: hidden;
  opacity: 0;
  font-size: 0.8125rem;
  line-height: 1.7;
  color: var(--muted);
  transition: max-height 220ms var(--ease), opacity 180ms var(--ease), margin-top 200ms var(--ease);
}

.page-about .tl-node:hover .tl-more,
.page-about .tl-node:focus .tl-more {
  max-height: 10em;
  opacity: 1;
  margin-top: 8px;
}

.page-about .about-origins__copy .media-frame {
  margin-block: 24px;
}

/* ---------- 四类常用人群 ---------- */
.page-about .crowd__intro {
  max-width: 68ch;
  margin: 0 0 30px;
  color: var(--ink);
  line-height: 1.8;
}

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

.page-about .crowd-card {
  position: relative;
  padding: 22px 20px 24px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.page-about .crowd-card::before {
  content: "";
  width: 34px;
  height: 2px;
  background: var(--crowd-accent, var(--cyan));
}

.page-about .crowd-card:nth-child(1) { --crowd-accent: var(--cyan); }
.page-about .crowd-card:nth-child(2) { --crowd-accent: var(--coral); }
.page-about .crowd-card:nth-child(3) { --crowd-accent: var(--amber); }
.page-about .crowd-card:nth-child(4) { --crowd-accent: var(--mist); }

.page-about .crowd-card__num {
  font-size: 1.625rem;
  font-weight: 500;
  line-height: 1;
  color: var(--crowd-accent, var(--cyan));
  letter-spacing: -0.02em;
}

.page-about .crowd-card__title {
  margin: 0;
  font-size: 1.125rem;
  font-weight: 800;
  letter-spacing: -0.01em;
}

.page-about .crowd-card__scene {
  margin: 0;
  font-size: 0.875rem;
  line-height: 1.75;
  color: var(--muted);
}

.page-about .crowd-card__label {
  margin: 6px 0 0;
  font-size: 0.75rem;
  letter-spacing: 0.08em;
  color: var(--cyan);
}

.page-about .crowd-card__links {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 7px;
}

.page-about .crowd-card__links li {
  position: relative;
  padding-left: 14px;
  font-size: 0.8125rem;
  line-height: 1.65;
  color: var(--ink);
}

.page-about .crowd-card__links li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.62em;
  width: 5px;
  height: 5px;
  background: var(--crowd-accent, var(--cyan));
  opacity: 0.8;
}

.page-about .crowd-card__go {
  margin-top: auto;
  padding-top: 12px;
  font-size: 0.8125rem;
  font-weight: 800;
  color: var(--cyan);
  text-decoration: underline;
  text-underline-offset: 4px;
  border-bottom: 0;
  transition: color var(--dur) var(--ease);
}

.page-about .crowd-card__go:hover {
  color: var(--coral);
}

.page-about .crowd__figure {
  margin-block: 34px 0;
}

/* ---------- 会员中心标签 ---------- */
.page-about .tabview__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 30px;
  align-items: start;
}

.page-about .tabview__demo {
  border: 1px solid var(--line-cyan);
  background: linear-gradient(150deg, var(--panel), var(--panel-deep));
  padding: 22px 20px 20px;
  clip-path: polygon(0 0, calc(100% - 14px) 0, 100% 14px, 100% 100%, 14px 100%, 0 calc(100% - 14px));
}

.page-about .tabs-demo {
  display: flex;
  flex-wrap: wrap;
  border-bottom: 1px solid var(--line);
}

.page-about .tabs-demo__tab {
  padding: 11px 14px 13px;
  font-size: 0.8125rem;
  color: var(--muted);
  border-bottom: 2px solid transparent;
}

.page-about .tabs-demo__tab.is-active {
  color: var(--ink);
  font-weight: 800;
  border-bottom-color: var(--coral);
  background: var(--coral-wash);
}

.page-about .tabs-demo__hint {
  margin: 16px 0 0;
  font-size: 0.75rem;
  letter-spacing: 0.04em;
  color: var(--amber);
}

.page-about .tabview__steps {
  list-style: none;
  counter-reset: tv;
  margin: 22px 0 0;
  padding: 0;
  display: grid;
  gap: 12px;
}

.page-about .tabview__steps li {
  position: relative;
  counter-increment: tv;
  padding-left: 36px;
  font-size: 0.9375rem;
  line-height: 1.75;
}

.page-about .tabview__steps li::before {
  content: counter(tv, decimal-leading-zero);
  position: absolute;
  left: 0;
  top: 2px;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--cyan);
  background: var(--cyan-wash);
  padding: 2px 5px;
}

.page-about .tabview__foot {
  margin-top: 20px;
  font-size: 0.875rem;
  color: var(--muted);
  padding-left: 14px;
  border-left: 2px solid var(--line-cyan-strong);
}

/* ---------- 标签云 ---------- */
.page-about .tags__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 34px;
  align-items: start;
}

.page-about .tags__copy .media-frame {
  margin-block: 24px;
}

.page-about .tag-cloud {
  display: grid;
  gap: 22px;
}

.page-about .tag-group__title {
  margin: 0 0 10px;
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 0.8125rem;
  font-weight: 800;
  letter-spacing: 0.05em;
  color: var(--muted);
}

.page-about .tag-group__title::after {
  content: "";
  flex: 1;
  height: 1px;
  background: var(--line);
}

.page-about .tag-group__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.page-about .tag {
  display: inline-block;
  padding: 5px 11px;
  font-size: 0.8125rem;
  line-height: 1.5;
  color: var(--ink);
  border: 1px solid var(--line-cyan);
  background: var(--cyan-faint);
  transition: opacity var(--dur) var(--ease), border-color var(--dur) var(--ease),
    background-color var(--dur) var(--ease);
}

.page-about .tag-group__list:hover .tag {
  opacity: 0.34;
}

.page-about .tag-group__list .tag:hover {
  opacity: 1;
  border-color: var(--line-cyan-strong);
  background: var(--cyan-wash);
}

/* ---------- 团队与维护 ---------- */
.page-about .team__stats {
  list-style: none;
  margin: 0 0 32px;
  padding: 1px;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .team__stats li {
  background: var(--panel);
  padding: 22px 20px;
  display: flex;
  flex-direction: column;
  gap: 9px;
}

.page-about .team__num {
  font-size: clamp(2rem, 6vw, 2.75rem);
  line-height: 1;
  font-weight: 500;
  color: var(--cyan);
  letter-spacing: -0.02em;
}

.page-about .team__label {
  font-size: 0.875rem;
  line-height: 1.6;
  color: var(--muted);
}

.page-about .team__copy p {
  max-width: 68ch;
}

.page-about .about-fold {
  margin-top: 24px;
  border: 1px solid var(--line-cyan);
  background: var(--panel);
}

.page-about .about-fold summary {
  cursor: pointer;
  list-style: none;
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 15px 20px;
  font-size: 0.9375rem;
  font-weight: 800;
  color: var(--ink);
}

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

.page-about .about-fold summary::before {
  content: "+";
  font-family: var(--font-mono);
  font-size: 1rem;
  color: var(--cyan);
  width: 14px;
  text-align: center;
}

.page-about .about-fold[open] summary::before {
  content: "−";
}

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

.page-about .about-fold > p {
  margin: 0;
  padding: 0 20px 20px 44px;
  font-size: 0.9375rem;
  line-height: 1.8;
  color: var(--muted);
  max-width: 78ch;
}

/* ---------- 服务范围与支持 ---------- */
.page-about .support__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 30px;
  align-items: start;
}

.page-about .support__list {
  list-style: none;
  margin: 18px 0;
  padding: 0;
  display: grid;
  gap: 10px;
}

.page-about .support__list li {
  position: relative;
  padding-left: 16px;
  font-size: 0.9375rem;
  line-height: 1.75;
  color: var(--ink);
}

.page-about .support__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.68em;
  width: 6px;
  height: 1px;
  background: var(--coral);
}

.page-about .support__panel {
  padding: 24px 22px 26px;
}

.page-about .support__contact {
  list-style: none;
  margin: 16px 0 0;
  padding: 0;
  display: grid;
  gap: 15px;
}

.page-about .support__contact li {
  display: grid;
  gap: 4px;
  padding-bottom: 13px;
  border-bottom: 1px solid var(--line);
}

.page-about .support__contact li:last-child {
  border-bottom: 0;
  padding-bottom: 0;
}

.page-about .support__value {
  font-size: 0.9375rem;
  line-height: 1.6;
  color: var(--ink);
  word-break: break-word;
}

.page-about .support__note {
  margin: 18px 0 0;
  font-size: 0.8125rem;
  line-height: 1.75;
  color: var(--muted);
  padding-top: 16px;
  border-top: 1px solid var(--line-cyan);
}

/* ---------- 直达入口 ---------- */
.page-about .about-next {
  padding-block: 8px 72px;
}

.page-about .about-next__bar {
  border: 1px solid var(--line-cyan);
  background: linear-gradient(100deg, rgba(47, 227, 208, 0.07), rgba(255, 107, 74, 0.06));
  clip-path: polygon(0 0, calc(100% - 14px) 0, 100% 14px, 100% 100%, 14px 100%, 0 calc(100% - 14px));
  padding: 24px 22px 26px;
  display: grid;
  gap: 16px;
}

.page-about .about-next__title {
  margin: 0;
  font-size: 1.125rem;
  font-weight: 800;
  letter-spacing: -0.01em;
}

.page-about .about-next__links {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 10px 12px;
}

.page-about .about-next__links a {
  display: inline-block;
  padding: 8px 14px;
  font-size: 0.875rem;
  font-weight: 700;
  color: var(--ink);
  border: 1px solid var(--line-cyan);
  background: rgba(11, 18, 32, 0.6);
  transition: border-color var(--dur) var(--ease), background-color var(--dur) var(--ease),
    color var(--dur) var(--ease);
}

.page-about .about-next__links a:hover {
  color: var(--cyan);
  border-color: var(--line-cyan-strong);
  background: var(--cyan-wash);
}

/* ---------- 断点 ---------- */
@media (min-width: 620px) {
  .page-about .crowd__grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 16px;
  }

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

@media (min-width: 900px) {
  .page-about .about-hero {
    padding-block: 34px 72px;
  }

  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    gap: 64px;
  }

  .page-about .section {
    padding-block: 76px;
  }

  .page-about .about-origins__grid {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    gap: var(--about-gap);
  }

  .page-about .tabview__grid {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
    gap: 52px;
  }

  .page-about .tags__grid {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
    gap: 52px;
  }

  .page-about .support__grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    gap: 52px;
  }

  .page-about .about-next__bar {
    grid-template-columns: minmax(0, auto) minmax(0, 1fr);
    align-items: center;
    gap: 28px;
    padding: 28px 30px;
  }
}

@media (min-width: 1100px) {
  .page-about .crowd__grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 14px;
  }

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

  .page-about .team__stats li {
    padding: 26px 22px;
  }
}
<<<END>>>