.page-about {
  --about-index-w: 152px;
  --about-pad: clamp(18px, 3.2vw, 40px);
  --about-gap: 14px;
  padding-block: clamp(14px, 2.4vw, 28px) clamp(48px, 7vw, 96px);
}

.page-about .about-shell {
  display: block;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  display: grid;
  gap: 22px;
  margin-top: 14px;
  padding-bottom: clamp(20px, 3vw, 34px);
  border-bottom: 1px solid var(--line-600);
}

.page-about .about-hero__main {
  min-width: 0;
}

.page-about .about-hero h1 {
  margin: 10px 0 0;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: clamp(34px, 6.4vw, 76px);
  line-height: 1.04;
  letter-spacing: -0.015em;
  color: var(--mist);
  text-wrap: balance;
}

.page-about .about-hl {
  color: var(--cyan);
}

.page-about .about-hero__lead {
  max-width: 38em;
  margin: 16px 0 0;
  font-size: clamp(15px, 1.5vw, 17px);
  line-height: 1.85;
  color: var(--mist);
  opacity: 0.84;
}

.page-about .stamps {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px 14px;
  margin: 0;
  padding: 16px 18px;
  list-style: none;
  border: 1px solid var(--line-600);
  border-radius: var(--r-md);
  background: var(--glass);
  -webkit-backdrop-filter: blur(8px);
  backdrop-filter: blur(8px);
}

.page-about .stamps li {
  min-width: 0;
}

.page-about .stamps b {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(20px, 2.2vw, 26px);
  font-weight: 600;
  line-height: 1.1;
  letter-spacing: -0.02em;
  color: var(--cyan);
}

.page-about .stamps li:nth-child(2) b {
  color: var(--orange);
}

.page-about .stamps span {
  display: block;
  margin-top: 4px;
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--slate);
}

/* ---------- 布局与章节索引 ---------- */
.page-about .about-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--about-gap);
  margin-top: clamp(18px, 2.8vw, 30px);
}

.page-about .about-index {
  position: sticky;
  top: 62px;
  z-index: 6;
  padding: 6px 0 8px;
  background: linear-gradient(180deg, var(--ink-900) 72%, rgba(7, 21, 33, 0));
}

.page-about .about-index ol {
  display: flex;
  gap: 8px;
  margin: 0;
  padding: 0 0 4px;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: thin;
  -webkit-overflow-scrolling: touch;
}

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

.page-about .about-index a {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 7px 12px;
  font-size: 12px;
  letter-spacing: 0.05em;
  color: var(--slate);
  text-decoration: none;
  white-space: nowrap;
  border: 1px solid var(--line-600);
  border-radius: 999px;
  background: rgba(14, 36, 54, 0.6);
  transition: color 180ms var(--ease), border-color 180ms var(--ease);
}

.page-about .about-index .ix {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--orange);
}

.page-about .about-index a:hover {
  color: var(--mist);
  border-color: var(--line-500);
}

.page-about .about-index a[aria-current] {
  color: var(--ink-900);
  border-color: var(--cyan);
  background: var(--cyan);
}

.page-about .about-index a[aria-current] .ix {
  color: var(--ink-800);
}

.page-about .about-body {
  display: grid;
  gap: var(--about-gap);
  min-width: 0;
}

/* ---------- 章节画板 ---------- */
.page-about .about-sec {
  position: relative;
  padding: var(--about-pad);
  overflow: hidden;
  border: 1px solid var(--line-600);
  border-radius: var(--r-lg);
  background: var(--glass);
  box-shadow: var(--shadow-panel);
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
}

.page-about .about-sec__num {
  position: absolute;
  top: calc(var(--about-pad) - 14px);
  right: calc(var(--about-pad) - 4px);
  font-family: var(--font-mono);
  font-size: clamp(46px, 8vw, 82px);
  font-weight: 700;
  line-height: 1;
  color: transparent;
  -webkit-text-stroke: 1px var(--line-500);
  opacity: 0.6;
  pointer-events: none;
  user-select: none;
}

.page-about .about-sec h2 {
  max-width: 24em;
  margin: 10px 0 0;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: clamp(24px, 3.2vw, 38px);
  line-height: 1.16;
  letter-spacing: -0.005em;
  color: var(--mist);
}

.page-about .about-sec__lead {
  max-width: 36em;
  margin: 14px 0 0;
  font-size: 15px;
  line-height: 1.85;
  color: var(--slate);
}

.page-about .about-sec__lead a,
.page-about .about-note a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(45, 226, 208, 0.4);
}

.page-about .about-sec__lead a:hover,
.page-about .about-note a:hover {
  border-bottom-color: var(--cyan);
}

/* ---------- 三问卡片 ---------- */
.page-about .about-cards {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
  margin-top: 20px;
}

.page-about .about-card {
  padding: 16px 16px 18px;
  border: 1px solid var(--line-600);
  border-top-width: 2px;
  border-radius: var(--r-md);
  background: rgba(10, 28, 43, 0.55);
}

.page-about .about-card--cyan {
  border-top-color: var(--cyan);
}

.page-about .about-card--orange {
  border-top-color: var(--orange);
}

.page-about .about-card--sage {
  border-top-color: var(--sage);
}

.page-about .about-card h3 {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-size: 19px;
  font-weight: 600;
  line-height: 1.3;
  color: var(--mist);
}

.page-about .about-card p {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--slate);
}

.page-about .about-note {
  margin-top: 16px;
  padding: 14px 16px;
  border-left: 3px solid var(--orange);
  border-radius: 0 var(--r-sm) var(--r-sm) 0;
  background: rgba(255, 155, 84, 0.07);
}

.page-about .about-note p {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--mist);
}

/* ---------- 时间线 ---------- */
.page-about .tl {
  position: relative;
  margin: 22px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .tl::before {
  content: "";
  position: absolute;
  left: 8px;
  top: 10px;
  bottom: 10px;
  width: 1px;
  background: linear-gradient(180deg, var(--cyan), var(--line-600) 70%);
}

.page-about .tl__item {
  position: relative;
  padding-left: 30px;
  margin-bottom: 10px;
}

.page-about .tl__item::before {
  content: "";
  position: absolute;
  left: 2px;
  top: 15px;
  width: 13px;
  height: 13px;
  border: 2px solid var(--line-500);
  border-radius: 50%;
  background: var(--ink-900);
}

.page-about .tl__item--current::before {
  border-color: var(--cyan);
  box-shadow: 0 0 0 4px rgba(45, 226, 208, 0.14);
}

.page-about .tl__item details {
  border: 1px solid var(--line-600);
  border-radius: var(--r-md);
  background: rgba(14, 36, 54, 0.55);
  transition: border-color 200ms var(--ease);
}

.page-about .tl__item details[open] {
  border-color: var(--line-500);
}

.page-about .tl__sum {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 8px 10px;
  padding: 12px 14px;
  cursor: pointer;
  list-style: none;
}

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

.page-about .tl__sum::after {
  content: "+";
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 15px;
  color: var(--slate);
  transition: transform 200ms var(--ease), color 200ms var(--ease);
}

.page-about .tl__item details[open] .tl__sum::after {
  transform: rotate(45deg);
  color: var(--cyan);
}

.page-about .tl__ver {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 600;
  color: var(--cyan);
}

.page-about .tl__item--current .tl__ver {
  color: var(--mint);
}

.page-about .tl__name {
  font-size: 14px;
  color: var(--mist);
}

.page-about .tl__body {
  padding: 0 14px 14px;
  font-size: 14px;
  line-height: 1.8;
  color: var(--slate);
}

/* ---------- 团队 ---------- */
.page-about .team-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
  margin-top: 20px;
}

.page-about .team-card {
  padding: 18px;
  border: 1px solid var(--line-600);
  border-radius: var(--r-md);
  background: rgba(14, 36, 54, 0.55);
  -webkit-backdrop-filter: blur(6px);
  backdrop-filter: blur(6px);
}

.page-about .team-card--solid {
  background: var(--ink-700);
  border-color: var(--line-500);
}

.page-about .team-card h3 {
  margin: 0 0 10px;
  font-family: var(--font-display);
  font-size: 20px;
  font-weight: 600;
  color: var(--mist);
}

.page-about .team-card p {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--slate);
}

/* ---------- 节奏列表 ---------- */
.page-about .rhythm {
  display: grid;
  gap: 12px;
  margin: 20px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .rhythm__item {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 8px;
  padding: 14px 16px;
  border: 1px solid var(--line-600);
  border-radius: var(--r-md);
  background: rgba(10, 28, 43, 0.5);
}

.page-about .rhythm__key {
  align-self: start;
  justify-self: start;
  padding: 3px 9px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--ink-900);
  background: var(--orange);
  border-radius: 999px;
}

.page-about .rhythm__item:nth-child(2) .rhythm__key {
  background: var(--cyan);
}

.page-about .rhythm__item:nth-child(3) .rhythm__key {
  background: var(--sage);
}

.page-about .rhythm__item:nth-child(4) .rhythm__key {
  background: var(--mint);
}

.page-about .rhythm__item h3 {
  margin: 0 0 6px;
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 600;
  color: var(--mist);
}

.page-about .rhythm__item p {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--slate);
}

/* ---------- 图 ---------- */
.page-about .about-figure {
  margin: 20px 0 0;
  overflow: hidden;
  border: 1px solid var(--line-600);
  border-radius: var(--r-md);
  background: var(--ink-800);
}

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

.page-about .about-figure figcaption {
  padding: 10px 14px;
  font-size: 12px;
  line-height: 1.6;
  letter-spacing: 0.04em;
  color: var(--slate);
  border-top: 1px solid var(--line-600);
}

/* ---------- 流程 ---------- */
.page-about .flow {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
  margin: 20px 0 0;
  padding: 0;
  list-style: none;
  counter-reset: none;
}

.page-about .flow__step {
  padding: 16px;
  border: 1px solid var(--line-600);
  border-radius: var(--r-md);
  background: rgba(14, 36, 54, 0.5);
}

.page-about .flow__no {
  display: block;
  margin-bottom: 8px;
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.06em;
  color: var(--cyan);
}

.page-about .flow__step h3 {
  margin: 0 0 6px;
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 600;
  color: var(--mist);
}

.page-about .flow__step p {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--slate);
}

/* ---------- 联络 ---------- */
.page-about .about-contact {
  display: grid;
  gap: 18px;
  margin-top: 20px;
  padding: clamp(16px, 2.4vw, 26px);
  border: 1px solid var(--line-500);
  border-radius: var(--r-md);
  background: var(--ink-700);
}

.page-about .about-contact__defs {
  display: grid;
  gap: 12px;
  margin: 0;
}

.page-about .about-contact__defs div {
  min-width: 0;
}

.page-about .about-contact__defs dt {
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--slate);
}

.page-about .about-contact__defs dd {
  margin: 4px 0 0;
  font-family: var(--font-mono);
  font-size: 14px;
  line-height: 1.6;
  color: var(--mist);
  overflow-wrap: anywhere;
}

.page-about .about-contact__acts {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

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

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

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

  .page-about .rhythm__item {
    grid-template-columns: 74px minmax(0, 1fr);
    align-items: start;
    gap: 14px;
  }

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

@media (min-width: 900px) {
  .page-about .about-hero {
    grid-template-columns: minmax(0, 1.6fr) minmax(0, 0.8fr);
    align-items: end;
    gap: 34px;
  }

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

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

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

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

@media (min-width: 1024px) {
  .page-about .about-layout {
    grid-template-columns: var(--about-index-w) minmax(0, 1fr);
    gap: 30px;
    align-items: start;
  }

  .page-about .about-index {
    top: 24px;
    padding: 0;
    background: none;
  }

  .page-about .about-index ol {
    flex-direction: column;
    gap: 2px;
    padding: 0;
    overflow: visible;
  }

  .page-about .about-index a {
    display: block;
    padding: 10px 0 10px 12px;
    font-size: 13px;
    line-height: 1.5;
    white-space: normal;
    border: 0;
    border-left: 1px solid var(--line-600);
    border-radius: 0;
    background: none;
  }

  .page-about .about-index a:hover {
    border-left-color: var(--line-500);
  }

  .page-about .about-index a[aria-current] {
    color: var(--mist);
    background: none;
    border-left: 2px solid var(--cyan);
  }

  .page-about .about-index a[aria-current] .ix {
    color: var(--cyan);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-index a,
  .page-about .tl__sum::after,
  .page-about .tl__item details {
    transition: none;
  }
}
<<<END>>>