.page-about {
  --about-rail: 184px;
  --about-edge: clamp(1rem, 4vw, 3rem);
  background: var(--ink-900);
  color: var(--paper);
  overflow-x: hidden;
  padding-bottom: clamp(3rem, 8vw, 5rem);
}

.page-about .about-wrap {
  width: 100%;
  max-width: var(--shell);
  margin-inline: auto;
  padding-inline: var(--about-edge);
}

.page-about a:focus-visible,
.page-about summary:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 3px;
  border-radius: 4px;
}

.page-about .about-crumb {
  padding-top: 1.25rem;
}

/* 首屏 */
.page-about .about-hero {
  position: relative;
}

.page-about .about-hero__inner {
  display: grid;
  gap: clamp(1.2rem, 3vw, 1.8rem);
  padding-top: clamp(1.5rem, 4vw, 2.5rem);
}

.page-about .about-hero__head .eyebrow {
  margin: 0;
}

.page-about .about-hero__head h1 {
  margin: 0.55rem 0 0;
  font-size: clamp(2.1rem, 7vw, 4.1rem);
  font-weight: 900;
  line-height: 1.06;
  letter-spacing: -0.01em;
  text-wrap: balance;
}

.page-about .about-hero__lede {
  margin: 0;
  font-size: clamp(0.95rem, 2vw, 1.05rem);
  line-height: 1.85;
  color: var(--pale);
  max-width: 40rem;
}

.page-about .about-stats {
  list-style: none;
  margin: clamp(1.2rem, 3vw, 1.8rem) 0 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 1rem clamp(1.5rem, 4vw, 2.5rem);
}

.page-about .about-stats li {
  display: grid;
  gap: 0.25rem;
}

.page-about .about-stats__n {
  font-family: var(--font-mono);
  font-size: clamp(1.9rem, 4.5vw, 2.6rem);
  font-weight: 800;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--cyan);
}

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

.page-about .about-stats li:nth-child(3) .about-stats__n {
  color: var(--paper);
}

.page-about .about-stats__u {
  font-size: 0.5em;
  margin-left: 0.08em;
}

.page-about .about-stats__k {
  font-size: 0.78rem;
  letter-spacing: 0.06em;
  color: var(--mist);
}

.page-about .about-hero__cta {
  margin-top: clamp(1.2rem, 3vw, 1.6rem);
  justify-self: start;
}

.page-about .about-hero__figure {
  margin: clamp(2rem, 5vw, 3rem) 0 0;
  position: relative;
  overflow: hidden;
  border-top: 1px solid var(--line-soft);
  border-bottom: 1px solid var(--line-soft);
}

.page-about .about-hero__figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 10;
  object-fit: cover;
}

.page-about .about-hero__figure::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(8, 23, 38, 0.1), rgba(8, 23, 38, 0.88) 92%);
  pointer-events: none;
}

/* 主体两栏 */
.page-about .about-body {
  display: grid;
  gap: clamp(1.5rem, 4vw, 2.5rem);
  padding-top: clamp(2rem, 5vw, 3.5rem);
}

.page-about .about-index__title {
  margin: 0 0 0.6rem;
  font-size: 0.72rem;
  letter-spacing: 0.18em;
  color: var(--mist);
}

.page-about .about-index__list {
  list-style: none;
  margin: 0;
  padding: 0 0 0.5rem;
  display: flex;
  gap: 0.5rem;
  overflow-x: auto;
  scrollbar-width: thin;
}

.page-about .about-index__list a {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.4rem 0.72rem;
  border: 1px solid var(--line-soft);
  border-radius: 999px;
  color: var(--pale);
  text-decoration: none;
  font-size: 0.82rem;
  white-space: nowrap;
  transition: border-color 0.18s var(--ease), color 0.18s var(--ease), background-color 0.18s var(--ease);
}

.page-about .about-index__list a:hover,
.page-about .about-index__list a:focus-visible {
  border-color: var(--cyan-line);
  color: var(--cyan);
  background: var(--cyan-soft);
}

.page-about .about-index__n {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--orange);
}

/* 章节 */
.page-about .about-sec {
  margin-top: clamp(2.2rem, 5vw, 3.4rem);
  padding-top: clamp(1.8rem, 4vw, 2.6rem);
  border-top: 1px solid var(--line-soft);
  scroll-margin-top: 5rem;
}

.page-about .about-sec:first-of-type {
  margin-top: 0;
  padding-top: 0;
  border-top: 0;
}

.page-about .about-sec__head {
  margin-bottom: clamp(1.2rem, 3vw, 1.8rem);
}

.page-about .about-sec__n {
  display: block;
  margin-bottom: 0.5rem;
  font-family: var(--font-mono);
  font-size: clamp(2rem, 6vw, 3.2rem);
  font-weight: 800;
  line-height: 1;
  color: transparent;
  -webkit-text-stroke: 1px var(--ink-600);
}

.page-about .about-sec h2 {
  margin: 0;
  font-size: clamp(1.45rem, 3.6vw, 2.1rem);
  font-weight: 900;
  line-height: 1.22;
  letter-spacing: -0.005em;
}

.page-about .about-sec__lede {
  margin: 0.7rem 0 0;
  color: var(--pale);
  line-height: 1.75;
  max-width: 40rem;
}

.page-about .about-sec__body p {
  margin: 0 0 1rem;
  max-width: 42rem;
  line-height: 1.85;
  color: var(--pale);
}

/* 使命引言 */
.page-about .about-quote {
  margin: clamp(1.5rem, 4vw, 2.2rem) 0;
  padding: clamp(1.1rem, 3vw, 1.5rem) clamp(1.1rem, 3vw, 1.5rem) clamp(1.1rem, 3vw, 1.5rem) clamp(1.2rem, 4vw, 1.9rem);
  border-left: 3px solid var(--cyan);
  border-radius: 0 var(--r-m) var(--r-m) 0;
  background: linear-gradient(100deg, var(--teal-900), var(--ink-850) 72%);
}

.page-about .about-quote p {
  margin: 0;
  font-size: clamp(1.1rem, 2.6vw, 1.42rem);
  font-weight: 800;
  line-height: 1.55;
  color: var(--paper);
}

.page-about .about-quote footer {
  margin-top: 0.6rem;
  font-size: 0.78rem;
  letter-spacing: 0.08em;
  color: var(--mist);
}

.page-about .about-inline-cta {
  margin: clamp(1.2rem, 3vw, 1.6rem) 0 0;
}

.page-about .about-inline-cta .btn {
  justify-self: start;
}

/* 四条内容线 */
.page-about .about-lines {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0.9rem;
}

.page-about .about-line {
  position: relative;
  padding: 1.1rem 1.1rem 1.2rem 1.35rem;
  border: 1px solid var(--line-soft);
  border-radius: var(--r-m);
  background: linear-gradient(150deg, var(--ink-800), var(--ink-850) 72%);
  transition: border-color 0.2s var(--ease), transform 0.2s var(--ease), box-shadow 0.2s var(--ease);
}

.page-about .about-line::before {
  content: "";
  position: absolute;
  left: 0;
  top: 1.05rem;
  bottom: 1.05rem;
  width: 3px;
  border-radius: 3px;
  background: var(--cyan);
}

.page-about .about-line:nth-child(even)::before {
  background: var(--orange);
}

.page-about .about-line:hover {
  border-color: var(--cyan-line);
  transform: translateY(-2px);
  box-shadow: var(--shadow-lift);
}

.page-about .about-line__meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  margin-bottom: 0.55rem;
}

.page-about .about-line__n {
  font-family: var(--font-mono);
  font-size: 0.74rem;
  color: var(--mist);
  opacity: 0.7;
}

.page-about .about-line h3 {
  margin: 0 0 0.5rem;
  font-size: 1.03rem;
  font-weight: 800;
  line-height: 1.4;
}

.page-about .about-line p {
  margin: 0 0 0.5rem;
  font-size: 0.9rem;
  line-height: 1.75;
  color: var(--pale);
}

.page-about .about-line__use {
  margin: 0;
  font-size: 0.82rem;
  color: var(--cyan);
}

.page-about .about-line:nth-child(even) .about-line__use {
  color: var(--yellow);
}

/* 团队 */
.page-about .about-team {
  display: grid;
  gap: clamp(1.2rem, 3vw, 1.8rem);
}

.page-about .about-team__fig {
  margin: 0;
  border-radius: var(--r-m);
  overflow: hidden;
  border: 1px solid var(--line-soft);
}

.page-about .about-team__fig img {
  display: block;
  width: 100%;
  height: 100%;
  aspect-ratio: 3 / 2;
  object-fit: cover;
}

.page-about .about-team__copy p {
  margin: 0;
  line-height: 1.85;
  color: var(--pale);
}

.page-about .about-groups {
  display: grid;
  gap: 0.6rem;
  margin-top: 1rem;
}

.page-about .about-group {
  border: 1px solid var(--line-soft);
  border-radius: var(--r-s);
  background: var(--ink-850);
  padding: 0.8rem 0.95rem;
  transition: border-color 0.2s var(--ease), background-color 0.2s var(--ease);
}

.page-about .about-group:hover {
  border-color: var(--cyan-line);
}

.page-about .about-group[open] {
  background: var(--ink-800);
  border-color: var(--cyan-line);
}

.page-about .about-group summary {
  display: flex;
  align-items: baseline;
  gap: 0.6rem;
  list-style: none;
  cursor: pointer;
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--paper);
}

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

.page-about .about-group summary::after {
  content: "+";
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 1.05rem;
  color: var(--cyan);
}

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

.page-about .about-group p {
  margin: 0.6rem 0 0;
  font-size: 0.87rem;
  line-height: 1.75;
  color: var(--pale);
}

/* 发展历程 */
.page-about .about-band {
  margin: 0 0 clamp(1.5rem, 4vw, 2rem);
  border-radius: var(--r-m);
  overflow: hidden;
  border: 1px solid var(--line-soft);
  position: relative;
}

.page-about .about-band img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 12 / 5;
  object-fit: cover;
  filter: saturate(0.9);
}

.page-about .about-band::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(90deg, rgba(8, 23, 38, 0.7), rgba(8, 23, 38, 0.15));
  pointer-events: none;
}

.page-about .about-tl {
  list-style: none;
  margin: 0;
  padding: 0 0 0 1.7rem;
  position: relative;
  display: grid;
  gap: 1rem;
}

.page-about .about-tl::before {
  content: "";
  position: absolute;
  left: 0.4rem;
  top: 0.6rem;
  bottom: 0.6rem;
  width: 2px;
  background: linear-gradient(180deg, var(--cyan), var(--orange) 68%, rgba(255, 107, 44, 0));
}

.page-about .about-tl__item {
  position: relative;
}

.page-about .about-tl__item::before {
  content: "";
  position: absolute;
  left: -1.7rem;
  top: 0.6rem;
  width: 0.8rem;
  height: 0.8rem;
  border-radius: 50%;
  background: var(--ink-900);
  border: 2px solid var(--cyan);
  transition: background-color 0.2s var(--ease), transform 0.2s var(--ease);
}

.page-about .about-tl__item--product::before {
  border-color: var(--orange);
}

.page-about .about-tl__year {
  display: inline-block;
  margin-bottom: 0.25rem;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  letter-spacing: 0.06em;
  color: var(--cyan);
}

.page-about .about-tl__item--product .about-tl__year {
  color: var(--orange);
}

.page-about .about-tl__box {
  border: 1px solid var(--line-soft);
  border-radius: var(--r-s);
  padding: 0.85rem 1rem;
  background: var(--ink-850);
  transition: border-color 0.2s var(--ease), transform 0.2s var(--ease);
}

.page-about .about-tl__box h3 {
  margin: 0 0 0.35rem;
  font-size: 1rem;
  font-weight: 800;
}

.page-about .about-tl__box p {
  margin: 0;
  font-size: 0.87rem;
  line-height: 1.75;
  color: var(--pale);
}

.page-about .about-tl__item:hover .about-tl__box {
  border-color: var(--cyan-line);
  transform: translateY(-2px);
}

.page-about .about-tl__item:hover::before {
  background: var(--cyan);
}

.page-about .about-tl__item--product:hover::before {
  background: var(--orange);
}

/* 覆盖范围 */
.page-about .about-cov {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 1px;
  background: var(--line-soft);
  border: 1px solid var(--line-soft);
  border-radius: var(--r-m);
  overflow: hidden;
}

.page-about .about-cov li {
  background: var(--ink-850);
  padding: 1rem 1rem 1.1rem;
  display: grid;
  gap: 0.22rem;
  align-content: start;
  transition: background-color 0.2s var(--ease);
}

.page-about .about-cov li:hover {
  background: var(--ink-800);
}

.page-about .about-cov__n {
  font-family: var(--font-mono);
  font-size: clamp(1.6rem, 4vw, 2.1rem);
  font-weight: 800;
  line-height: 1;
  color: var(--cyan);
}

.page-about .about-cov li:nth-child(2) .about-cov__n,
.page-about .about-cov li:nth-child(5) .about-cov__n {
  color: var(--orange);
}

.page-about .about-cov__u {
  font-size: 0.5em;
  margin-left: 0.08em;
}

.page-about .about-cov__k {
  font-size: 0.82rem;
  font-weight: 700;
  color: var(--paper);
}

.page-about .about-cov__d {
  font-size: 0.78rem;
  line-height: 1.6;
  color: var(--mist);
}

.page-about .about-promise {
  margin-top: clamp(1.4rem, 4vw, 2rem);
  padding: clamp(1.1rem, 3vw, 1.5rem);
  border: 1px solid var(--line-soft);
  border-radius: var(--r-m);
  background: linear-gradient(120deg, var(--teal-900), var(--ink-800) 76%);
}

.page-about .about-promise h3 {
  margin: 0 0 0.8rem;
  font-size: 1rem;
  font-weight: 800;
}

.page-about .about-promise__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0.7rem;
}

.page-about .about-promise__list li {
  position: relative;
  padding-left: 1.1rem;
  font-size: 0.87rem;
  line-height: 1.78;
  color: var(--pale);
}

.page-about .about-promise__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.62em;
  width: 0.42rem;
  height: 0.42rem;
  background: var(--cyan);
  transform: rotate(45deg);
}

.page-about .about-promise__list strong {
  color: var(--paper);
}

/* 结尾入口 */
.page-about .about-cta {
  margin-top: clamp(2.2rem, 5vw, 3.4rem);
  padding-top: clamp(1.8rem, 4vw, 2.6rem);
  border-top: 1px solid var(--line-soft);
}

.page-about .about-cta h2 {
  margin: 0 0 1rem;
  font-size: clamp(1.3rem, 3vw, 1.7rem);
  font-weight: 900;
}

.page-about .about-cta__grid {
  display: grid;
  gap: 0.8rem;
}

.page-about .about-cta__card {
  display: grid;
  gap: 0.3rem;
  align-content: start;
  padding: 1rem 1.1rem 1.15rem;
  border: 1px solid var(--line-soft);
  border-radius: var(--r-m);
  background: var(--ink-850);
  text-decoration: none;
  transition: border-color 0.2s var(--ease), transform 0.2s var(--ease), background-color 0.2s var(--ease);
}

.page-about .about-cta__card:hover,
.page-about .about-cta__card:focus-visible {
  border-color: var(--cyan-line);
  background: var(--ink-800);
  transform: translateY(-2px);
}

.page-about .about-cta__k {
  font-size: 0.72rem;
  letter-spacing: 0.14em;
  color: var(--orange);
}

.page-about .about-cta__t {
  font-size: 1.05rem;
  font-weight: 800;
  color: var(--paper);
}

.page-about .about-cta__d {
  font-size: 0.82rem;
  line-height: 1.65;
  color: var(--mist);
}

/* 桌面布局 */
@media (min-width: 900px) {
  .page-about .about-hero__inner {
    grid-template-columns: minmax(0, 1.02fr) minmax(0, 0.98fr);
    gap: clamp(2rem, 5vw, 3.5rem);
    align-items: start;
  }

  .page-about .about-hero__figure img {
    aspect-ratio: 16 / 6;
  }

  .page-about .about-line:nth-child(even) {
    margin-left: clamp(1.5rem, 8vw, 5rem);
  }

  .page-about .about-line:nth-child(odd) {
    margin-right: clamp(1rem, 4vw, 2.5rem);
  }

  .page-about .about-team {
    grid-template-columns: minmax(0, 0.92fr) minmax(0, 1.08fr);
    align-items: start;
  }

  .page-about .about-tl__item:nth-child(even) {
    margin-left: clamp(1.5rem, 7vw, 4.5rem);
  }
}

@media (min-width: 1024px) {
  .page-about .about-body {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    gap: clamp(2rem, 5vw, 4rem);
    align-items: start;
  }

  .page-about .about-index {
    position: sticky;
    top: 5.5rem;
    border-left: 1px solid var(--line-soft);
    padding-left: 1rem;
  }

  .page-about .about-index__list {
    flex-direction: column;
    gap: 0.1rem;
    overflow: visible;
    padding-bottom: 0;
  }

  .page-about .about-index__list a {
    border: 0;
    border-radius: 0;
    padding: 0.35rem 0;
    background: none;
    color: var(--mist);
  }

  .page-about .about-index__list a:hover,
  .page-about .about-index__list a:focus-visible {
    color: var(--cyan);
    background: none;
  }
}

@media (min-width: 860px) {
  .page-about .about-cta__grid {
    grid-template-columns: 1.2fr 0.9fr 1.1fr;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-line:hover,
  .page-about .about-tl__item:hover .about-tl__box,
  .page-about .about-cta__card:hover {
    transform: none;
  }
}
<<<END>>>