/* ===== 平台介绍 ===== */
.page-about {
  --about-measure: 68ch;
  --about-toc-w: 208px;
  --about-cut: 20px;
  background-color: var(--ink-900);
  color: var(--cool);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  isolation: isolate;
  overflow: hidden;
  padding-top: calc(var(--header-h) + var(--sp-4));
  padding-bottom: var(--sp-5);
  border-bottom: 1px solid var(--line);
  background:
    radial-gradient(120% 90% at 84% -12%, rgba(0, 229, 192, 0.16), transparent 62%),
    radial-gradient(90% 70% at 0% 104%, rgba(255, 162, 58, 0.09), transparent 58%),
    var(--ink-900);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background-image:
    linear-gradient(90deg, rgba(27, 74, 62, 0.6) 1px, transparent 1px),
    linear-gradient(180deg, rgba(27, 74, 62, 0.38) 1px, transparent 1px);
  background-size: 88px 88px, 88px 88px;
  opacity: 0.5;
  -webkit-mask-image: radial-gradient(120% 92% at 72% 0%, #000 18%, transparent 76%);
  mask-image: radial-gradient(120% 92% at 72% 0%, #000 18%, transparent 76%);
}

.page-about .breadcrumb {
  font-size: 13px;
  color: var(--mute);
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  align-items: center;
  margin-bottom: var(--sp-4);
}

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

.page-about .breadcrumb a:hover {
  color: var(--cyan-soft);
}

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

.page-about .about-hero__grid {
  display: grid;
  gap: var(--sp-4);
  align-items: start;
}

.page-about .about-hero h1 {
  margin: var(--sp-2) 0 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(30px, 6.4vw, 56px);
  line-height: 1.12;
  letter-spacing: -0.02em;
  color: var(--paper);
  max-width: 15em;
}

.page-about .about-hero__intro {
  margin: var(--sp-3) 0 0;
  max-width: 48ch;
  font-size: 17px;
  line-height: 1.78;
  color: var(--cool);
}

.page-about .about-hero__links {
  display: flex;
  flex-wrap: wrap;
  gap: var(--sp-3);
  margin-top: var(--sp-4);
}

.page-about .about-hero__jump {
  position: relative;
  font-size: 14px;
  font-weight: 600;
  color: var(--cyan);
  text-decoration: none;
  padding-bottom: 4px;
  border-bottom: 1px solid rgba(0, 229, 192, 0.42);
  transition: color 0.18s ease, border-color 0.18s ease;
}

.page-about .about-hero__jump:hover {
  color: var(--cyan-soft);
  border-color: var(--cyan-soft);
}

/* 首屏数据面板 */
.page-about .about-facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  -webkit-clip-path: polygon(0 0, 100% 0, 100% calc(100% - var(--about-cut)), calc(100% - var(--about-cut)) 100%, 0 100%);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - var(--about-cut)), calc(100% - var(--about-cut)) 100%, 0 100%);
}

.page-about .about-facts__item {
  background: var(--ink-800);
  padding: var(--sp-2) var(--sp-2) var(--sp-3);
}

.page-about .about-facts__num {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 32px;
  line-height: 1;
  letter-spacing: -0.02em;
  font-variant-numeric: tabular-nums;
  color: var(--cyan);
}

.page-about .about-facts__label {
  margin: 8px 0 0;
  font-size: 13px;
  line-height: 1.55;
  color: var(--mute);
}

/* 首屏图 */
.page-about .about-hero__figure {
  margin-top: var(--sp-5);
}

.page-about .about-hero__figure .media-frame {
  position: relative;
  overflow: hidden;
  border: 1px solid var(--line);
  background: var(--ink-800);
}

.page-about .about-hero__figure img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
  aspect-ratio: 16 / 9;
  filter: saturate(0.9) contrast(1.04);
}

.page-about .about-hero__cap {
  margin-top: 10px;
  font-size: 12px;
  letter-spacing: 0.02em;
  color: var(--mute);
}

/* ---------- 主体布局 ---------- */
.page-about .about-body {
  padding-block: var(--sp-6);
  background:
    linear-gradient(180deg, rgba(12, 31, 25, 0.72), var(--ink-900) 42%);
}

.page-about .about-body__grid {
  display: grid;
  gap: var(--sp-5);
}

/* 目录 */
.page-about .about-toc {
  border-left: 1px solid var(--line);
  padding-left: var(--sp-2);
}

.page-about .about-toc__title {
  margin: 0 0 var(--sp-2);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.28em;
  text-transform: uppercase;
  color: var(--mute);
}

.page-about .about-toc__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 2px;
}

.page-about .about-toc__list a {
  display: flex;
  gap: 10px;
  align-items: baseline;
  padding: 7px 0;
  font-size: 14px;
  line-height: 1.5;
  color: var(--mute);
  text-decoration: none;
  transition: color 0.18s ease;
}

.page-about .about-toc__list a:hover {
  color: var(--cyan-soft);
}

.page-about .about-toc__list a[aria-current="true"] {
  color: var(--cyan);
  font-weight: 600;
}

.page-about .about-toc__num {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: rgba(0, 229, 192, 0.55);
}

.page-about .about-toc__list a[aria-current="true"] .about-toc__num {
  color: var(--amber);
}

.page-about .about-toc__note {
  margin: var(--sp-3) 0 0;
  font-size: 12px;
  line-height: 1.6;
  color: var(--mute);
  max-width: 20em;
}

/* ---------- 章节 ---------- */
.page-about .chapter {
  padding-bottom: var(--sp-6);
}

.page-about .chapter + .chapter {
  border-top: 1px solid var(--line);
  padding-top: var(--sp-5);
}

.page-about .chapter__num {
  display: block;
  margin-bottom: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.24em;
  color: var(--cyan);
}

.page-about .chapter h2 {
  margin: 0 0 var(--sp-3);
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(23px, 4vw, 38px);
  line-height: 1.2;
  letter-spacing: -0.02em;
  color: var(--paper);
  max-width: 22em;
}

.page-about .chapter h3 {
  margin: var(--sp-2) 0 6px;
  font-size: 18px;
  font-weight: 700;
  line-height: 1.4;
  color: var(--paper);
}

.page-about .chapter p {
  margin: 0 0 var(--sp-3);
  max-width: var(--about-measure);
  font-size: 16px;
  line-height: 1.78;
  color: var(--cool);
}

.page-about .chapter p a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(0, 229, 192, 0.4);
}

.page-about .chapter p a:hover {
  color: var(--cyan-soft);
  border-color: var(--cyan-soft);
}

.page-about .chapter__list {
  list-style: none;
  margin: var(--sp-3) 0 var(--sp-4);
  padding: 0;
  display: grid;
  gap: var(--sp-2);
  max-width: var(--about-measure);
}

.page-about .chapter__list li {
  position: relative;
  padding-left: 22px;
  font-size: 15px;
  line-height: 1.75;
  color: var(--cool);
}

.page-about .chapter__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.78em;
  width: 11px;
  height: 1px;
  background: var(--cyan);
}

.page-about .chapter__list strong {
  color: var(--paper);
  font-weight: 700;
}

.page-about .chapter__aside {
  padding-left: var(--sp-2);
  border-left: 2px solid var(--line);
  font-size: 14px;
  color: var(--mute) !important;
}

/* ---------- 时间线 ---------- */
.page-about .tl-wrap {
  margin: var(--sp-4) 0 var(--sp-4);
  padding: var(--sp-3) 0 var(--sp-1) var(--sp-3);
  border: 1px solid var(--line);
  background:
    linear-gradient(160deg, rgba(0, 229, 192, 0.06), transparent 46%),
    var(--ink-800);
  overflow: hidden;
}

.page-about .tl-rail {
  display: flex;
  overflow-x: auto;
  padding-bottom: var(--sp-3);
  scroll-snap-type: x proximity;
  scrollbar-width: thin;
  scrollbar-color: var(--line) transparent;
}

.page-about .tl-rail::-webkit-scrollbar {
  height: 4px;
}

.page-about .tl-rail::-webkit-scrollbar-thumb {
  background: var(--line);
}

.page-about .tl-node {
  position: relative;
  flex: 0 0 auto;
  width: 182px;
  margin-right: var(--sp-3);
  padding: var(--sp-3) var(--sp-2) 0 0;
  border-top: 1px solid var(--line);
  scroll-snap-align: start;
  transition: transform 0.18s ease;
}

.page-about .tl-node::before {
  content: "";
  position: absolute;
  top: -5px;
  left: 0;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--ink-900);
  border: 1px solid var(--cyan);
}

.page-about .tl-node:last-child::before {
  background: var(--amber);
  border-color: var(--amber);
  box-shadow: 0 0 0 4px rgba(255, 162, 58, 0.16);
}

.page-about .tl-node:hover {
  transform: translateY(-3px);
}

.page-about .tl-node__ver {
  display: block;
  margin-bottom: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--amber);
  font-variant-numeric: tabular-nums;
}

.page-about .tl-node:last-child .tl-node__ver {
  color: var(--cyan);
}

.page-about .tl-node__title {
  margin: 0;
  max-width: none;
  font-size: 15px;
  font-weight: 700;
  line-height: 1.45;
  color: var(--paper);
}

.page-about .tl-node__desc {
  margin: 8px 0 0;
  max-width: none;
  font-size: 13px;
  line-height: 1.65;
  color: var(--mute);
}

/* ---------- 三级流程 ---------- */
.page-about .flow {
  list-style: none;
  margin: var(--sp-4) 0 var(--sp-4);
  padding: 0;
  display: grid;
  gap: var(--sp-4);
  counter-reset: flow;
}

.page-about .flow__step {
  position: relative;
  background: var(--ink-800);
  border: 1px solid var(--line);
  padding: var(--sp-3);
  -webkit-clip-path: polygon(0 0, 100% 0, 100% calc(100% - 16px), calc(100% - 16px) 100%, 0 100%);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 16px), calc(100% - 16px) 100%, 0 100%);
}

.page-about .flow__step::after {
  content: "";
  position: absolute;
  left: var(--sp-3);
  bottom: -14px;
  width: 8px;
  height: 8px;
  border-right: 1px solid var(--cyan);
  border-bottom: 1px solid var(--cyan);
  transform: rotate(45deg);
}

.page-about .flow__step:last-child::after {
  display: none;
}

.page-about .flow__idx {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.2em;
  color: var(--cyan);
}

.page-about .flow__title {
  margin: 6px 0 0;
  max-width: none;
  font-size: 17px;
  font-weight: 700;
  color: var(--paper);
}

.page-about .flow__desc {
  margin: 6px 0 0;
  max-width: none;
  font-size: 14px;
  line-height: 1.68;
  color: var(--mute);
}

/* 时间戳带 */
.page-about .stamp-band {
  display: flex;
  align-items: flex-start;
  gap: var(--sp-3);
  margin: var(--sp-4) 0;
  padding: var(--sp-3);
  border: 1px solid rgba(255, 162, 58, 0.32);
  background: linear-gradient(100deg, rgba(255, 162, 58, 0.12), transparent 72%);
}

.page-about .stamp-band__num {
  margin: 0;
  font-family: var(--font-mono);
  font-size: clamp(38px, 8vw, 56px);
  line-height: 1;
  font-variant-numeric: tabular-nums;
  color: var(--amber);
  flex: 0 0 auto;
}

.page-about .stamp-band__text {
  margin: 0;
  max-width: 42ch;
  font-size: 14px;
  line-height: 1.72;
  color: var(--cool);
}

.page-about .stamp-band__text strong {
  color: var(--amber);
  font-weight: 700;
}

/* ---------- 团队 ---------- */
.page-about .team-grid {
  display: grid;
  gap: 1px;
  margin: var(--sp-4) 0;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .team-card {
  background: var(--ink-800);
  padding: var(--sp-3);
}

.page-about .team-card__tag {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--cyan);
  border: 1px solid rgba(0, 229, 192, 0.34);
  padding: 3px 8px;
}

.page-about .team-card p {
  margin: 0;
  max-width: none;
  font-size: 14px;
  line-height: 1.72;
  color: var(--mute);
}

/* ---------- 图片容器 ---------- */
.page-about .chapter__figure {
  margin: var(--sp-4) 0;
}

.page-about .chapter__figure .media-frame {
  position: relative;
  overflow: hidden;
  border: 1px solid var(--line);
  background: var(--ink-700);
}

.page-about .chapter__figure img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
  aspect-ratio: 16 / 10;
  filter: saturate(0.92) contrast(1.05);
}

.page-about .chapter__figure .media-frame--wide img {
  aspect-ratio: 21 / 10;
}

.page-about .chapter__figcap {
  margin-top: 10px;
  font-size: 12px;
  color: var(--mute);
  letter-spacing: 0.02em;
}

/* ---------- 覆盖范围 ---------- */
.page-about .coverage-card {
  margin: var(--sp-4) 0;
  padding: var(--sp-4) var(--sp-3);
  background: var(--paper);
  color: var(--ink-900);
  -webkit-clip-path: polygon(0 0, 100% 0, 100% calc(100% - 26px), calc(100% - 26px) 100%, 0 100%);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 26px), calc(100% - 26px) 100%, 0 100%);
}

.page-about .coverage-card__grid {
  margin: 0;
  display: grid;
  gap: var(--sp-3);
}

.page-about .coverage-card dt {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.2em;
  color: #4E6A61;
  margin-bottom: 4px;
}

.page-about .coverage-card dd {
  margin: 0;
  font-size: 14px;
  line-height: 1.6;
  color: var(--ink-900);
}

.page-about .coverage-card__num {
  font-family: var(--font-mono);
  font-size: 20px;
  font-weight: 700;
  font-variant-numeric: tabular-nums;
  color: var(--ink-800);
  letter-spacing: -0.01em;
}

/* ---------- 结尾 ---------- */
.page-about .chapter--end {
  padding-bottom: 0;
}

.page-about .end-cta {
  margin-top: var(--sp-4);
  padding: var(--sp-4) var(--sp-3);
  border: 1px solid var(--line);
  background:
    radial-gradient(110% 140% at 100% 0%, rgba(0, 229, 192, 0.14), transparent 62%),
    var(--ink-800);
  display: grid;
  gap: var(--sp-3);
  justify-items: start;
}

.page-about .end-cta__text {
  margin: 0;
  max-width: 34ch;
  font-size: 15px;
  line-height: 1.7;
  color: var(--cool);
}

.page-about .end-cta .btn {
  position: relative;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 13px 26px;
  font-size: 15px;
  font-weight: 700;
  text-decoration: none;
  color: var(--ink-900);
  background: var(--cyan);
  border: 1px solid var(--cyan);
  transition: background 0.18s ease, color 0.18s ease;
}

.page-about .end-cta .btn:hover {
  background: var(--cyan-soft);
  border-color: var(--cyan-soft);
}

.page-about .end-cta .btn__ver {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  padding: 2px 6px;
  background: rgba(7, 19, 15, 0.16);
  color: var(--ink-900);
}

/* ---------- 响应式 ---------- */
@media (min-width: 640px) {
  .page-about .about-body {
    padding-block: var(--sp-7);
  }

  .page-about .about-hero__figure {
    margin-top: var(--sp-6);
  }

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

  .page-about .chapter__figure .media-frame img {
    aspect-ratio: 2 / 1;
  }
}

@media (min-width: 768px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.35fr) minmax(0, 1fr);
    gap: var(--sp-5);
    align-items: end;
  }

  .page-about .chapter__head {
    position: relative;
    padding-left: 44px;
  }

  .page-about .chapter__num {
    position: absolute;
    left: 2px;
    top: 8px;
    margin: 0;
    transform: rotate(90deg);
    transform-origin: left top;
    white-space: nowrap;
  }

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

  .page-about .flow__step::after {
    left: auto;
    right: -14px;
    bottom: auto;
    top: 50%;
    margin-top: -5px;
    transform: rotate(-45deg);
  }

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

  .page-about .end-cta {
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: center;
    justify-items: start;
    padding: var(--sp-4);
  }

  .page-about .coverage-card {
    padding: var(--sp-4);
  }
}

@media (min-width: 960px) {
  .page-about .about-body__grid {
    grid-template-columns: var(--about-toc-w) minmax(0, 1fr);
    column-gap: var(--sp-6);
  }

  .page-about .about-toc {
    position: sticky;
    top: calc(var(--header-h) + var(--sp-3));
    align-self: start;
  }

  .page-about .about-hero__figure {
    margin-top: var(--sp-7);
  }

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

  .page-about .tl-node {
    width: 200px;
  }
}

@media (min-width: 1200px) {
  .page-about .about-hero {
    padding-bottom: var(--sp-6);
  }

  .page-about .about-facts__num {
    font-size: 38px;
  }
}
<<<END>>>