/* ============================================================
   品牌档案 / page-about
   以时间轴为主轴，左侧编号与年份，右侧短段落加数据锚点
   ============================================================ */

.page-about {
  --about-axis: rgba(184, 121, 31, .4);
  --about-rule: rgba(47, 74, 102, .18);
  --about-tl-col: 118px;
  background: var(--paper-50);
  color: var(--text-900);
  overflow-x: hidden;
}

.page-about .container {
  width: 100%;
  max-width: var(--w-max);
  margin: 0 auto;
  padding-left: var(--gutter);
  padding-right: var(--gutter);
}

/* ---------- 首屏：深色档案区 ---------- */

.page-about .about-hero {
  position: relative;
  padding: calc(var(--head-h) + clamp(30px, 5vw, 62px)) 0 clamp(48px, 7vw, 88px);
  background:
    radial-gradient(120% 88% at 10% -10%, rgba(47, 74, 102, .62) 0%, rgba(10, 18, 27, 0) 64%),
    var(--ink-950);
  color: var(--paper-50);
  overflow: hidden;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(228, 192, 131, .055) 1px, transparent 1px),
    linear-gradient(90deg, rgba(228, 192, 131, .055) 1px, transparent 1px);
  background-size: 68px 68px;
  pointer-events: none;
}

.page-about .about-hero > .container {
  position: relative;
  z-index: 1;
}

.page-about .about-hero__crumbs {
  font-family: var(--font-mono);
  font-size: .74rem;
  letter-spacing: .1em;
  color: var(--on-ink-dim);
  margin-bottom: clamp(24px, 4vw, 44px);
}

.page-about .about-hero__crumbs a {
  color: var(--amber-300);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color .2s var(--ease);
}

.page-about .about-hero__crumbs a:hover {
  border-bottom-color: var(--amber-600);
}

.page-about .about-hero__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(22px, 4vw, 34px);
}

.page-about .about-hero__aside {
  border-left: 2px solid var(--amber-600);
  padding-left: 14px;
}

.page-about .about-hero__idx {
  font-size: .72rem;
  letter-spacing: .16em;
  color: var(--amber-600);
  margin: 0 0 10px;
}

.page-about .about-hero__stamp {
  font-size: .92rem;
  line-height: 1.7;
  color: var(--amber-300);
  margin: 0 0 12px;
}

.page-about .about-hero__note {
  font-size: .76rem;
  line-height: 1.9;
  color: var(--on-ink-dim);
  margin: 0;
}

.page-about .about-hero h1 {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.85rem, 5.6vw, 3.2rem);
  line-height: 1.2;
  letter-spacing: -.01em;
  color: var(--paper-50);
  margin: 0 0 clamp(18px, 2.4vw, 26px);
  max-width: 24ch;
}

.page-about .about-hero .lede {
  font-size: clamp(1rem, 1.25vw, 1.08rem);
  line-height: 1.9;
  color: var(--on-ink);
  max-width: 60ch;
  margin: 0;
}

/* 章节索引 */
.page-about .about-hero__toc {
  margin-top: clamp(32px, 5vw, 56px);
  border-top: 1px solid var(--line-amber);
  padding-top: clamp(18px, 2.6vw, 26px);
}

.page-about .about-hero__toc .toc__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px clamp(16px, 3vw, 30px);
}

.page-about .toc__link {
  display: flex;
  flex-direction: column;
  gap: 5px;
  font-size: .86rem;
  line-height: 1.5;
  color: var(--on-ink);
  text-decoration: none;
  padding-bottom: 7px;
  border-bottom: 1px solid transparent;
  transition: color .2s var(--ease), border-color .2s var(--ease);
}

.page-about .toc__link .mono {
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: .14em;
  color: var(--amber-600);
}

.page-about .toc__link:hover,
.page-about .toc__link:focus-visible,
.page-about .toc__link[data-active] {
  color: var(--amber-300);
  border-bottom-color: var(--amber-600);
  outline: none;
}

.page-about .toc__link[data-active] .mono {
  color: var(--amber-300);
}

/* 首屏通栏图 */
.page-about .about-hero__figure {
  margin: clamp(34px, 5vw, 56px) 0 0;
}

.page-about .about-hero__figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  border: 1px solid var(--line-amber);
  filter: saturate(.68) sepia(.16) contrast(1.02);
}

.page-about .img-frame__cap {
  display: block;
  margin-top: 12px;
  font-family: var(--font-mono);
  font-size: .74rem;
  line-height: 1.75;
  letter-spacing: .02em;
  color: var(--text-500);
}

.page-about .about-hero__figure .img-frame__cap {
  color: var(--on-ink-dim);
}

/* ---------- 分区底板 ---------- */

.page-about .about-block {
  padding: clamp(52px, 8vw, 104px) 0;
}

.page-about .about-block--paper {
  background: var(--paper-50);
  color: var(--text-900);
}

.page-about .about-block--paper2 {
  background: var(--paper-100);
  color: var(--text-900);
  border-top: 1px solid var(--line-300);
  border-bottom: 1px solid var(--line-300);
}

.page-about .about-block--ink {
  background: var(--ink-950);
  color: var(--paper-50);
}

/* 编号 + 内容 两栏 */
.page-about .about-sec {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(16px, 2.6vw, 22px);
}

.page-about .about-sec__num .mono {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: clamp(1.45rem, 2.6vw, 2rem);
  font-weight: 600;
  line-height: 1;
  letter-spacing: .06em;
  color: var(--amber-600);
  padding-left: 14px;
  border-left: 2px solid var(--amber-600);
}

.page-about .about-block--ink .about-sec__num .mono {
  color: var(--amber-300);
  border-left-color: var(--amber-300);
}

.page-about .about-sec__body h2 {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(1.4rem, 2.5vw, 2rem);
  line-height: 1.34;
  letter-spacing: -.005em;
  margin: 0 0 clamp(16px, 2.2vw, 24px);
  max-width: 26ch;
}

.page-about .about-sec__body > p {
  font-size: clamp(1rem, 1.1vw, 1.04rem);
  line-height: 1.9;
  margin: 0 0 1.1em;
  max-width: 68ch;
}

.page-about .about-block--ink .about-sec__body > p {
  color: var(--on-ink);
}

.page-about .about-sec__body > p:last-child {
  margin-bottom: 0;
}

/* ---------- 01 四块服务 ---------- */

.page-about .about-pillars {
  list-style: none;
  margin: clamp(28px, 4vw, 44px) 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: 0;
  border-top: 1px solid var(--line-300);
}

.page-about .about-pillars li {
  padding: 20px 0 22px;
  border-bottom: 1px solid var(--line-300);
}

.page-about .about-pillars__idx {
  display: block;
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: .14em;
  color: var(--amber-600);
  margin-bottom: 8px;
}

.page-about .about-pillars h3 {
  font-family: var(--font-display);
  font-size: 1.1rem;
  font-weight: 700;
  margin: 0 0 8px;
}

.page-about .about-pillars p {
  font-size: .95rem;
  line-height: 1.82;
  color: var(--text-500);
  margin: 0;
  max-width: 56ch;
}

/* ---------- 02 时间轴 ---------- */

.page-about .about-tl {
  list-style: none;
  margin: clamp(28px, 4vw, 46px) 0 0;
  padding: 0;
  position: relative;
}

.page-about .tl-item {
  position: relative;
  padding-left: 22px;
}

.page-about .tl-item::before {
  content: "";
  position: absolute;
  left: -4px;
  top: 9px;
  width: 8px;
  height: 8px;
  background: var(--amber-600);
  transform: rotate(45deg);
}

.page-about .tl-item__mark {
  display: flex;
  align-items: baseline;
  gap: 12px;
  flex-wrap: wrap;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--line-300);
  margin-bottom: 12px;
}

.page-about .tl-item__year {
  font-size: 1rem;
  font-weight: 600;
  letter-spacing: .02em;
  color: var(--amber-600);
}

.page-about .tl-item__no {
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: .16em;
  color: var(--text-500);
}

.page-about .tl-item__body {
  padding-bottom: clamp(28px, 3.6vw, 44px);
}

.page-about .tl-item:last-child .tl-item__body {
  padding-bottom: 0;
}

.page-about .tl-item h3 {
  font-family: var(--font-display);
  font-size: 1.16rem;
  font-weight: 700;
  line-height: 1.45;
  margin: 0 0 10px;
}

.page-about .tl-item__body > p {
  font-size: .97rem;
  line-height: 1.85;
  margin: 0 0 .9em;
  max-width: 64ch;
}

.page-about .tl-item__fact {
  display: inline-flex;
  align-items: baseline;
  flex-wrap: wrap;
  gap: 6px;
  margin: 4px 0 0;
  padding: 8px 14px;
  font-size: .85rem;
  line-height: 1.7;
  color: var(--text-500);
  background: var(--paper-50);
  border-left: 2px solid var(--amber-600);
}

.page-about .about-block--paper2 .tl-item__fact {
  background: var(--paper-50);
}

.page-about .tl-item__fact .mono {
  font-family: var(--font-mono);
  font-size: 1.08rem;
  font-weight: 600;
  color: var(--amber-600);
  letter-spacing: .02em;
}

/* ---------- 03 团队 ---------- */

.page-about .about-spread {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(26px, 4vw, 44px);
}

.page-about .about-team {
  list-style: none;
  margin: clamp(24px, 3.4vw, 38px) 0 0;
  padding: 0;
  border-top: 1px solid var(--line-300);
}

.page-about .about-team li {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 16px;
  padding: 20px 0 22px;
  border-bottom: 1px solid var(--line-300);
}

.page-about .about-team__num {
  font-family: var(--font-mono);
  font-size: clamp(1.6rem, 3.4vw, 2.1rem);
  font-weight: 600;
  line-height: 1;
  color: var(--amber-600);
  min-width: 2.6ch;
}

.page-about .about-team__text h3 {
  font-family: var(--font-display);
  font-size: 1.1rem;
  font-weight: 700;
  margin: 0 0 8px;
}

.page-about .about-team__text p {
  font-size: .95rem;
  line-height: 1.82;
  color: var(--text-500);
  margin: 0;
  max-width: 56ch;
}

.page-about .about-team__tail {
  font-size: .93rem;
  line-height: 1.85;
  color: var(--text-500);
  margin: 20px 0 0;
  padding-left: 14px;
  border-left: 2px solid var(--line-300);
  max-width: 62ch;
}

.page-about .about-spread__media {
  margin: 0;
}

.page-about .about-spread__media img,
.page-about .about-split__media img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  border: 1px solid var(--line-300);
  filter: saturate(.68) sepia(.16) contrast(1.02);
}

/* ---------- 04 规则维护 ---------- */

.page-about .about-split {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(26px, 4vw, 46px);
  margin-top: clamp(26px, 3.6vw, 40px);
}

.page-about .about-split__media {
  margin: 0;
  max-width: 420px;
}

.page-about .about-steps {
  list-style: none;
  counter-reset: step;
  margin: 0;
  padding: 0;
}

.page-about .about-steps li {
  counter-increment: step;
  position: relative;
  padding: 15px 0 15px 42px;
  border-top: 1px solid var(--line-300);
  font-size: .96rem;
  line-height: 1.85;
  color: var(--text-900);
  max-width: 62ch;
}

.page-about .about-steps li:last-child {
  border-bottom: 1px solid var(--line-300);
}

.page-about .about-steps li::before {
  content: counter(step, decimal-leading-zero);
  position: absolute;
  left: 0;
  top: 17px;
  font-family: var(--font-mono);
  font-size: .76rem;
  letter-spacing: .1em;
  color: var(--amber-600);
}

.page-about .about-steps strong {
  font-weight: 700;
  color: var(--text-900);
}

/* ---------- 05 服务能力（深色） ---------- */

.page-about .about-metrics {
  list-style: none;
  margin: clamp(26px, 3.6vw, 42px) 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: 0;
}

.page-about .about-metrics li {
  padding: 16px 0 18px;
  border-top: 1px solid var(--line-amber);
}

.page-about .about-metrics__num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(1.6rem, 3.6vw, 2.15rem);
  font-weight: 600;
  line-height: 1.15;
  color: var(--amber-300);
  letter-spacing: .01em;
}

.page-about .about-metrics__lbl {
  display: block;
  margin-top: 6px;
  font-size: .82rem;
  line-height: 1.7;
  color: var(--on-ink-dim);
}

.page-about .about-chart {
  margin: clamp(34px, 5vw, 56px) 0 0;
  padding: clamp(20px, 3vw, 30px) clamp(16px, 2.6vw, 28px) clamp(16px, 2.4vw, 24px);
  border: 1px solid var(--line-amber);
  background: rgba(20, 40, 60, .38);
}

.page-about .about-chart svg {
  display: block;
  width: 100%;
  height: auto;
}

.page-about .chart__grid line {
  stroke: rgba(228, 192, 131, .14);
  stroke-width: 1;
}

.page-about .chart__line {
  fill: none;
  stroke: var(--amber-600);
  stroke-width: 2.2;
  stroke-linejoin: round;
  stroke-linecap: round;
}

.page-about .chart__line--flat {
  stroke: rgba(240, 235, 225, .5);
  stroke-width: 1.6;
  stroke-dasharray: 7 6;
}

.page-about .chart__dots circle {
  fill: var(--ink-950);
  stroke: var(--amber-300);
  stroke-width: 2;
}

.page-about .about-chart__legend {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 26px;
  margin-top: 18px;
  font-family: var(--font-mono);
  font-size: .74rem;
  letter-spacing: .05em;
  color: var(--on-ink-dim);
}

.page-about .about-chart__key {
  display: inline-block;
  width: 20px;
  height: 2px;
  margin-right: 8px;
  vertical-align: middle;
}

.page-about .about-chart__key--amber {
  background: var(--amber-600);
}

.page-about .about-chart__key--flat {
  background: rgba(240, 235, 225, .5);
}

.page-about .about-chart .img-frame__cap {
  color: var(--on-ink-dim);
  margin-top: 14px;
}

/* ---------- 06 合作与入口 ---------- */

.page-about .about-next {
  margin-top: clamp(30px, 4.4vw, 48px);
  padding-top: clamp(22px, 3vw, 32px);
  border-top: 1px solid var(--line-300);
}

.page-about .about-next__lead {
  font-family: var(--font-mono);
  font-size: .78rem;
  letter-spacing: .08em;
  color: var(--text-500);
  margin: 0 0 16px;
}

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

.page-about .about-next__list .btn {
  text-decoration: none;
  font-size: .92rem;
  line-height: 1;
  padding: 12px 20px;
  white-space: nowrap;
}

/* ---------- 响应式 ---------- */

@media (min-width: 620px) {
  .page-about .about-hero__toc .toc__list {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .about-pillars {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    column-gap: clamp(20px, 3vw, 36px);
  }

  .page-about .about-metrics {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    column-gap: clamp(16px, 2.6vw, 30px);
  }

  .page-about .about-metrics li {
    border-top: none;
    border-left: 1px solid var(--line-amber);
    padding-left: clamp(14px, 2vw, 22px);
  }

  .page-about .about-metrics li:nth-child(3n + 1) {
    border-left: none;
    padding-left: 0;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(170px, 19%) minmax(0, 1fr);
    gap: clamp(34px, 5vw, 76px);
    align-items: start;
  }

  .page-about .about-hero__aside {
    position: sticky;
    top: calc(var(--head-h) + 26px);
  }

  .page-about .about-hero__toc .toc__list {
    grid-template-columns: repeat(6, minmax(0, 1fr));
  }

  .page-about .about-sec {
    grid-template-columns: minmax(78px, 8%) minmax(0, 1fr);
    gap: clamp(28px, 4vw, 62px);
  }

  .page-about .about-sec__num {
    position: sticky;
    top: calc(var(--head-h) + 30px);
    align-self: start;
  }

  .page-about .about-tl::before {
    content: "";
    position: absolute;
    left: var(--about-tl-col);
    top: 10px;
    bottom: 34px;
    width: 1px;
    background: linear-gradient(180deg, var(--amber-600) 0%, rgba(184, 121, 31, .12) 100%);
  }

  .page-about .tl-item {
    display: grid;
    grid-template-columns: var(--about-tl-col) minmax(0, 1fr);
    gap: clamp(26px, 3.6vw, 52px);
    padding-left: 0;
  }

  .page-about .tl-item::before {
    left: calc(var(--about-tl-col) - 4px);
  }

  .page-about .tl-item__mark {
    flex-direction: column;
    align-items: flex-end;
    text-align: right;
    gap: 6px;
    padding-bottom: 0;
    border-bottom: none;
    margin-bottom: 0;
  }
}

@media (min-width: 1040px) {
  .page-about .about-spread {
    grid-template-columns: minmax(0, 1fr) minmax(240px, 34%);
    gap: clamp(30px, 4vw, 56px);
    align-items: start;
  }

  .page-about .about-split {
    grid-template-columns: minmax(210px, 30%) minmax(0, 1fr);
    gap: clamp(28px, 4vw, 56px);
    align-items: start;
  }

  .page-about .about-pillars {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    column-gap: clamp(18px, 2.4vw, 30px);
  }

  .page-about .about-pillars li {
    padding-right: 10px;
  }
}

@media (min-width: 1200px) {
  .page-about .about-metrics {
    grid-template-columns: repeat(5, minmax(0, 1fr));
  }

  .page-about .about-metrics li:nth-child(3n + 1) {
    border-left: 1px solid var(--line-amber);
    padding-left: clamp(14px, 2vw, 22px);
  }

  .page-about .about-metrics li:first-child {
    border-left: none;
    padding-left: 0;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .toc__link,
  .page-about .about-hero__crumbs a {
    transition: none;
  }
}
<<<END>>>