.page-about {
  --tm-idx: 172px;
  --tm-gap: clamp(20px, 3.4vw, 44px);
  --tm-soft: rgba(51, 230, 209, .12);
  background: var(--bg);
  color: var(--text);
  --placeholder: rgba(18, 34, 74, .9);
}

/* ---------- 首屏 ---------- */
.page-about .tm-hero {
  position: relative;
  isolation: isolate;
  padding-block: clamp(16px, 2.4vw, 32px) clamp(48px, 7vw, 96px);
}

.page-about .tm-hero::before {
  content: "";
  position: absolute;
  z-index: -1;
  inset: 0 0 auto auto;
  width: min(78%, 900px);
  height: 100%;
  background:
    radial-gradient(circle at 78% 18%, rgba(200, 255, 51, .16), transparent 58%),
    radial-gradient(circle at 30% 74%, rgba(51, 230, 209, .14), transparent 62%),
    linear-gradient(150deg, rgba(18, 34, 74, .92), rgba(4, 10, 24, 0) 72%);
  clip-path: polygon(18% 0, 100% 0, 100% 100%, 0 100%);
  pointer-events: none;
}

.page-about .tm-hero-grid {
  display: grid;
  gap: clamp(26px, 4vw, 52px);
  align-items: center;
}

.page-about .tm-hero h1 {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(2.1rem, 6.4vw, 4.4rem);
  line-height: 1.06;
  letter-spacing: -.03em;
  margin: 12px 0 0;
  max-width: 15em;
}

.page-about .tm-hero-lead {
  margin: 20px 0 0;
  max-width: 34em;
  color: var(--text-dim);
  font-size: clamp(15px, 1.6vw, 17px);
  line-height: 1.85;
}

.page-about .tm-hero-stats {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: clamp(18px, 3vw, 40px);
  margin: 28px 0 0;
  padding: 0;
}

.page-about .tm-hero-stats li {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding-left: 14px;
  border-left: 2px solid var(--accent);
}

.page-about .tm-hero-stats .num {
  font-family: var(--font-mono);
  font-size: clamp(1.35rem, 3vw, 1.9rem);
  font-weight: 700;
  color: var(--accent);
  letter-spacing: -.02em;
  line-height: 1.1;
}

.page-about .tm-stat-label {
  font-size: 12.5px;
  letter-spacing: .08em;
  color: var(--text-dim);
}

.page-about .tm-hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 30px;
}

.page-about .tm-hero-figure {
  position: relative;
  margin: 0;
  border: 1px solid var(--line-strong);
  background: var(--surface);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - var(--cut)), calc(100% - var(--cut)) 100%, 0 100%);
}

.page-about .tm-hero-figure::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(51, 230, 209, .10) 1px, transparent 1px),
    linear-gradient(90deg, rgba(51, 230, 209, .10) 1px, transparent 1px);
  background-size: 34px 34px;
  pointer-events: none;
}

.page-about .tm-hero-figure img,
.page-about .tm-flow-figure img,
.page-about .tm-partner-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
}

.page-about .figure-caption {
  font-size: 12.5px;
  color: var(--text-dim);
  line-height: 1.7;
}

/* ---------- 章节通用 ---------- */
.page-about .tm-chapter-head {
  max-width: 46em;
  margin-bottom: clamp(24px, 4vw, 48px);
}

.page-about .tm-chapter-head .section-title,
.page-about .tm-origin-body .section-title,
.page-about .tm-partners-copy .section-title {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.5rem, 3.6vw, 2.5rem);
  line-height: 1.18;
  letter-spacing: -.02em;
  margin: 10px 0 0;
}

.page-about .section-sub {
  color: var(--text-dim);
  line-height: 1.85;
  margin: 14px 0 0;
}

/* ---------- 01 起源 ---------- */
.page-about .tm-origin {
  display: grid;
  gap: var(--tm-gap);
  border-top: 1px solid var(--line);
  padding-top: clamp(28px, 4vw, 56px);
}

.page-about .tm-origin-aside {
  display: flex;
  align-items: baseline;
  gap: 12px;
}

.page-about .tm-chapter-no {
  font-family: var(--font-mono);
  font-size: clamp(2.4rem, 7vw, 4.4rem);
  font-weight: 700;
  line-height: .9;
  color: transparent;
  -webkit-text-stroke: 1.5px var(--lime-600);
  margin: 0;
}

.page-about .tm-aside-text {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--text-dim);
  white-space: nowrap;
}

.page-about .tm-origin-body p {
  line-height: 1.9;
  color: var(--text-dim);
  margin: 16px 0 0;
  max-width: 40em;
}

.page-about .tm-origin-body p:first-of-type {
  color: var(--text);
}

.page-about .tm-factline {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 26px 0 0;
  padding: 0;
}

.page-about .tm-factline li {
  font-size: 12.5px;
  letter-spacing: .04em;
  color: var(--text);
  background: var(--surface-2);
  border-left: 3px solid var(--accent-2);
  padding: 8px 12px;
}

.page-about .tm-factline .num {
  font-family: var(--font-mono);
  font-weight: 700;
  color: var(--accent-2);
}

/* ---------- 02 时间线 ---------- */
.page-about .tm-timeline {
  border-top: 1px solid var(--line);
}

.page-about .tm-timeline-body {
  display: grid;
  gap: var(--tm-gap);
}

.page-about .tm-index-title {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .16em;
  color: var(--text-dim);
  margin: 0 0 12px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--line-strong);
}

.page-about .tm-index ol {
  list-style: none;
  display: flex;
  gap: 10px;
  margin: 0;
  padding: 0;
  overflow-x: auto;
}

.page-about .tm-index li {
  flex: 0 0 auto;
}

.page-about .tm-index a {
  display: inline-flex;
  align-items: baseline;
  gap: 6px;
  padding: 7px 12px;
  font-size: 13px;
  color: var(--text-dim);
  text-decoration: none;
  border: 1px solid var(--line);
  background: var(--surface);
  clip-path: polygon(0 0, 100% 0, 100% 100%, 8px 100%, 0 calc(100% - 8px));
  transition: color .2s var(--ease), border-color .2s var(--ease), background .2s var(--ease);
}

.page-about .tm-index a .num {
  font-family: var(--font-mono);
  font-weight: 700;
  color: var(--accent);
}

.page-about .tm-index a:hover,
.page-about .tm-index a:focus-visible {
  color: var(--text);
  border-color: var(--accent);
  background: var(--surface-2);
}

.page-about .tm-track {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .tm-era {
  position: relative;
  padding: 0 0 clamp(26px, 4vw, 46px) 26px;
  border-left: 1px solid var(--line-strong);
}

.page-about .tm-era:last-child {
  padding-bottom: 0;
  border-left-color: transparent;
}

.page-about .tm-era-dot {
  position: absolute;
  left: -5px;
  top: 6px;
  width: 9px;
  height: 9px;
  background: var(--accent);
  transform: rotate(45deg);
  box-shadow: 0 0 0 4px rgba(200, 255, 51, .12);
}

.page-about .tm-era-year {
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: .1em;
  color: var(--accent-2);
  margin: 0;
}

.page-about .tm-era h3 {
  font-family: var(--font-display);
  font-size: clamp(1.05rem, 2.2vw, 1.3rem);
  font-weight: 700;
  letter-spacing: -.01em;
  margin: 8px 0 0;
}

.page-about .tm-era p:last-child {
  color: var(--text-dim);
  line-height: 1.9;
  margin: 10px 0 0;
  max-width: 40em;
  font-size: 15px;
}

/* ---------- 03 团队 ---------- */
.page-about .tm-roles-section {
  border-top: 1px solid var(--line);
}

.page-about .tm-role-filter {
  margin-bottom: 22px;
}

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

.page-about .tm-role {
  position: relative;
  padding: 22px 20px 24px;
  background: var(--surface);
  border: 1px solid var(--line);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 14px), calc(100% - 14px) 100%, 0 100%);
  transition: border-color .25s var(--ease), transform .25s var(--ease), background .25s var(--ease);
}

.page-about .tm-role:hover {
  transform: translateY(-3px);
  border-color: var(--accent);
  background: var(--surface-2);
}

.page-about .tm-role-count {
  font-family: var(--font-mono);
  font-size: clamp(1.9rem, 4vw, 2.5rem);
  font-weight: 700;
  line-height: 1;
  color: var(--accent);
  margin: 0;
}

.page-about .tm-role h3 {
  font-family: var(--font-display);
  font-size: 1.02rem;
  font-weight: 700;
  margin: 10px 0 0;
}

.page-about .tm-role p:last-child {
  font-size: 14px;
  line-height: 1.85;
  color: var(--text-dim);
  margin: 10px 0 0;
}

.page-about .tm-role:nth-child(2) .tm-role-count { color: var(--accent-2); }
.page-about .tm-role:nth-child(3) .tm-role-count { color: var(--white-50); }
.page-about .tm-role:nth-child(4) .tm-role-count { color: var(--orange-500); }

.page-about .filter-empty {
  font-size: 14px;
  color: var(--text-dim);
  padding: 18px;
  border: 1px dashed var(--line-strong);
}

/* ---------- 04 流程 ---------- */
.page-about .tm-flow {
  border-top: 1px solid var(--line);
}

.page-about .tm-flow-figure {
  margin: 0 0 clamp(20px, 3vw, 32px);
  background: var(--surface);
  border: 1px solid var(--line);
}

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

.page-about .tm-step {
  position: relative;
  padding: 20px 18px 22px;
  background: linear-gradient(160deg, var(--surface-2), var(--surface));
  border-top: 2px solid var(--accent-2);
  clip-path: polygon(0 0, 100% 0, 100% 100%, 12px 100%, 0 calc(100% - 12px));
  transition: border-color .25s var(--ease), background .25s var(--ease);
}

.page-about .tm-step:hover,
.page-about .tm-step:focus-within {
  border-top-color: var(--accent);
  background: linear-gradient(160deg, rgba(200, 255, 51, .12), var(--surface-2));
}

.page-about .tm-step-no {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .14em;
  color: var(--accent);
  margin: 0;
}

.page-about .tm-step h3 {
  font-family: var(--font-display);
  font-size: 1.05rem;
  font-weight: 700;
  margin: 8px 0 0;
}

.page-about .tm-step p:last-child {
  font-size: 14px;
  line-height: 1.85;
  color: var(--text-dim);
  margin: 10px 0 0;
}

/* ---------- 05 合作 ---------- */
.page-about .tm-partners {
  border-top: 1px solid var(--line);
}

.page-about .tm-partners-grid {
  display: grid;
  gap: clamp(24px, 4vw, 48px);
  align-items: start;
}

.page-about .tm-partners-copy > p {
  color: var(--text-dim);
  line-height: 1.9;
  margin: 16px 0 0;
  max-width: 34em;
}

.page-about .tm-partner-list {
  list-style: none;
  margin: 22px 0 26px;
  padding: 0;
  display: grid;
  gap: 14px;
}

.page-about .tm-partner-list li {
  position: relative;
  padding-left: 18px;
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--text-dim);
}

.page-about .tm-partner-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: .72em;
  width: 8px;
  height: 8px;
  background: var(--accent-2);
  transform: rotate(45deg);
}

.page-about .tm-partner-list strong {
  display: block;
  color: var(--text);
  font-family: var(--font-display);
  font-size: 15px;
  letter-spacing: .01em;
  margin-bottom: 2px;
}

.page-about .tm-partner-figure {
  margin: 0;
  background: var(--surface);
  border: 1px solid var(--line-strong);
  clip-path: polygon(14px 0, 100% 0, 100% 100%, 0 100%, 0 14px);
}

/* ---------- 06 原则 ---------- */
.page-about .tm-principles {
  border-top: 1px solid var(--line);
}

.page-about .tm-principle-list {
  display: grid;
  gap: 16px;
}

.page-about .tm-principle {
  position: relative;
  padding: 24px 20px;
  border-left: 3px solid var(--line-strong);
  background: var(--surface);
  transition: border-left-color .25s var(--ease), background .25s var(--ease);
}

.page-about .tm-principle:hover {
  border-left-color: var(--accent);
  background: var(--surface-2);
}

.page-about .tm-principle-no {
  font-family: var(--font-mono);
  font-size: clamp(2rem, 5vw, 3.2rem);
  font-weight: 700;
  line-height: .9;
  margin: 0;
  color: transparent;
  -webkit-text-stroke: 1.4px var(--lime-600);
}

.page-about .tm-principle h3 {
  font-family: var(--font-display);
  font-size: 1.15rem;
  font-weight: 800;
  letter-spacing: -.01em;
  margin: 12px 0 0;
}

.page-about .tm-principle p:last-child {
  font-size: 14.5px;
  line-height: 1.9;
  color: var(--text-dim);
  margin: 10px 0 0;
}

/* ---------- 收尾 ---------- */
.page-about .tm-outro {
  margin-top: clamp(40px, 6vw, 80px);
  padding-block: clamp(34px, 5vw, 64px);
  background:
    linear-gradient(100deg, rgba(18, 34, 74, .95), rgba(10, 21, 48, .6)),
    repeating-linear-gradient(-45deg, rgba(200, 255, 51, .10) 0 2px, transparent 2px 14px);
  border-top: 1px solid var(--line-strong);
  border-bottom: 1px solid var(--line-strong);
}

.page-about .tm-outro-inner {
  display: grid;
  gap: 24px;
}

.page-about .tm-outro h2 {
  font-family: var(--font-display);
  font-size: clamp(1.4rem, 3.4vw, 2.2rem);
  font-weight: 800;
  letter-spacing: -.02em;
  line-height: 1.2;
  margin: 0;
}

.page-about .tm-outro p {
  color: var(--text-dim);
  line-height: 1.85;
  margin: 12px 0 0;
  max-width: 38em;
  font-size: 15px;
}

.page-about .tm-outro-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  align-content: start;
}

/* ---------- 平板以上 ---------- */
@media (min-width: 720px) {
  .page-about .tm-roles {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

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

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

  .page-about .tm-principle:nth-child(2) {
    margin-top: 26px;
  }

  .page-about .tm-principle:nth-child(3) {
    margin-top: 52px;
  }

  .page-about .tm-outro-inner {
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: end;
  }

  .page-about .tm-outro-actions {
    justify-content: flex-end;
    max-width: 30em;
  }
}

/* ---------- 桌面 ---------- */
@media (min-width: 900px) {
  .page-about .tm-hero-grid {
    grid-template-columns: minmax(0, 1.08fr) minmax(0, .92fr);
  }

  .page-about .tm-origin {
    grid-template-columns: minmax(0, 190px) minmax(0, 1fr);
    gap: clamp(28px, 4vw, 64px);
  }

  .page-about .tm-origin-aside {
    flex-direction: column;
    align-items: flex-start;
    gap: 14px;
    position: sticky;
    top: calc(var(--header-h) + 24px);
    align-self: start;
  }

  .page-about .tm-timeline-body {
    grid-template-columns: var(--tm-idx) minmax(0, 1fr);
    gap: clamp(28px, 4vw, 64px);
  }

  .page-about .tm-index {
    position: sticky;
    top: calc(var(--header-h) + 24px);
    align-self: start;
  }

  .page-about .tm-index ol {
    flex-direction: column;
    overflow: visible;
  }

  .page-about .tm-index a {
    width: 100%;
    justify-content: flex-start;
  }

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

  .page-about .tm-role:nth-child(even) {
    margin-top: 28px;
  }

  .page-about .tm-steps {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 10px;
  }

  .page-about .tm-step:not(:last-child)::after {
    content: "";
    position: absolute;
    right: -7px;
    top: 50%;
    width: 4px;
    height: 24px;
    background: var(--accent);
    transform: translateY(-50%) skewX(-20deg);
    opacity: .55;
  }

  .page-about .tm-partners-grid {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, .95fr);
  }
}

@media (min-width: 1100px) {
  .page-about .tm-era {
    padding-left: 34px;
  }

  .page-about .tm-era p:last-child,
  .page-about .tm-origin-body p {
    font-size: 16px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .tm-role,
  .page-about .tm-step,
  .page-about .tm-principle,
  .page-about .tm-index a {
    transition: none;
  }

  .page-about .tm-role:hover {
    transform: none;
  }
}
<<<END>>>