.page-about {
  --gauge-col: clamp(84px, 10vw, 132px);
  --about-gap: clamp(16px, 2.6vw, 36px);
  background: var(--field);
  color: var(--body);
}

.page-about .about-wrap {
  padding-block: clamp(18px, 2.6vw, 32px) clamp(48px, 7vw, 96px);
}

/* ---------- 首屏框景 ---------- */
.page-about .about-head {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(18px, 2.4vw, 28px);
  margin-top: clamp(16px, 2.2vw, 26px);
  padding: clamp(22px, 3.4vw, 46px);
  border: 2px solid var(--steel);
  background: var(--panel-2);
  box-shadow: var(--shadow-hard);
}

.page-about .about-head__kicker {
  margin: 0 0 14px;
  font-size: 12px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--cyan);
}

.page-about .about-head__title {
  margin: 0 0 16px;
  font-size: clamp(26px, 4vw, 52px);
  font-weight: 900;
  letter-spacing: -0.02em;
  line-height: 1.22;
  color: var(--headline);
  max-width: 20ch;
}

.page-about .about-head__lede {
  margin: 0;
  max-width: 62ch;
  font-size: clamp(15px, 1.05vw, 17px);
  line-height: 1.85;
  color: var(--body);
}

.page-about .about-head__gauge {
  display: flex;
  flex-direction: row;
  align-items: center;
  gap: 12px;
  padding-top: 14px;
  border-top: var(--line);
}

.page-about .about-head__gauge-mark {
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--note-dim);
}

.page-about .about-head__gauge-line {
  flex: 1;
  height: 8px;
  border-left: 1px solid var(--steel);
  background-image: repeating-linear-gradient(to right, var(--steel) 0 1px, transparent 1px 14px);
}

/* ---------- 数字锚点带 ---------- */
.page-about .about-facts {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  margin: clamp(24px, 3.4vw, 44px) 0 0;
  padding: 0;
  list-style: none;
  border-top: var(--line);
  border-bottom: var(--line);
}

.page-about .about-facts__item {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: clamp(16px, 2vw, 24px) clamp(12px, 1.6vw, 20px);
  border-right: var(--line);
  transition: background-color var(--t-fast);
}

.page-about .about-facts__item:last-child {
  border-right: 0;
}

.page-about .about-facts__item:hover {
  background: var(--panel);
}

.page-about .about-facts__num {
  font-size: clamp(28px, 3.6vw, 46px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--headline);
}

.page-about .about-facts__item:nth-child(2) .about-facts__num {
  color: var(--cyan);
}

.page-about .about-facts__item:nth-child(4) .about-facts__num {
  color: var(--violet);
}

.page-about .about-facts__txt {
  font-size: 13px;
  line-height: 1.6;
  color: var(--note);
}

/* ---------- 小节目录 ---------- */
.page-about .about-toc {
  margin-top: clamp(22px, 3vw, 38px);
  border-top: var(--line);
  border-bottom: var(--line);
  overflow-x: auto;
  scrollbar-width: thin;
}

.page-about .about-toc__list {
  display: flex;
  min-width: max-content;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-toc__item {
  display: flex;
}

.page-about .about-toc__link {
  display: inline-flex;
  align-items: center;
  gap: 0.6em;
  padding: 13px clamp(14px, 2vw, 24px);
  border-right: var(--line);
  font-size: 14px;
  white-space: nowrap;
  color: var(--note);
  text-decoration: none;
  transition: color var(--t-fast), background-color var(--t-fast), box-shadow var(--t-fast);
}

.page-about .about-toc__link .mono {
  font-size: 12px;
  color: var(--note-dim);
}

.page-about .about-toc__link:hover,
.page-about .about-toc__link[aria-current="true"] {
  color: var(--headline);
  background: var(--panel);
  box-shadow: inset 0 -2px 0 var(--cyan);
}

.page-about .about-toc__link:hover .mono,
.page-about .about-toc__link[aria-current="true"] .mono {
  color: var(--cyan);
}

/* ---------- 章节通用 ---------- */
.page-about .about-sec {
  margin-top: clamp(48px, 6.5vw, 92px);
}

.page-about .about-sec__lead {
  margin: 0 0 clamp(20px, 2.6vw, 32px);
  max-width: 66ch;
  font-size: clamp(15px, 1.05vw, 17px);
  line-height: 1.85;
  color: var(--body);
}

.page-about .about-sec__foot {
  margin: clamp(18px, 2.4vw, 28px) 0 0;
  max-width: 66ch;
  padding-left: 16px;
  border-left: 2px solid var(--cyan);
  font-size: 15px;
  line-height: 1.8;
  color: var(--body);
}

/* ---------- 时间轴 ---------- */
.page-about .tl {
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .tl__item {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
  padding-block: clamp(20px, 2.8vw, 34px);
  border-top: var(--line);
}

.page-about .tl__item:last-child {
  border-bottom: var(--line);
}

.page-about .tl__axis {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 8px 12px;
}

.page-about .tl__no {
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--note-dim);
}

.page-about .tl__year {
  font-size: 15px;
  letter-spacing: 0.02em;
  color: var(--headline);
}

.page-about .tl__label {
  align-self: center;
  padding: 2px 8px;
  border: 1px solid var(--grid);
  font-size: 12px;
  color: var(--cyan);
}

.page-about .tl__copy {
  align-self: center;
  margin-left: auto;
  padding: 3px 10px;
  border: 1px solid var(--grid);
  background: transparent;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.06em;
  color: var(--note-dim);
  cursor: pointer;
  transition: color var(--t-fast), border-color var(--t-fast), background-color var(--t-fast);
}

.page-about .tl__copy:hover,
.page-about .tl__copy:focus-visible {
  color: var(--field);
  border-color: var(--cyan);
  background: var(--cyan);
}

.page-about .tl__copy[data-copied] {
  color: var(--cyan);
  border-color: var(--cyan);
}

.page-about .tl__content {
  padding: clamp(16px, 2.4vw, 28px);
  border: 2px solid var(--steel);
  background: var(--panel);
  transition: box-shadow var(--t-fast), border-color var(--t-fast);
}

.page-about .tl__content:hover {
  border-color: var(--cyan);
  box-shadow: var(--shadow-mid);
}

.page-about .tl__title {
  margin: 0 0 10px;
  font-size: clamp(17px, 1.6vw, 21px);
  font-weight: 700;
  line-height: 1.5;
  letter-spacing: -0.01em;
  color: var(--headline);
}

.page-about .tl__content p {
  margin: 0 0 14px;
  font-size: 15px;
  line-height: 1.85;
}

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

.page-about .tl__media {
  margin: 16px 0;
}

.page-about .tl__media .media__img {
  width: 100%;
  height: auto;
  object-fit: cover;
}

/* ---------- 横向阶段对比条 ---------- */
.page-about .tl__item--band {
  padding-block: clamp(10px, 1.6vw, 20px);
  border-top: 0;
}

.page-about .stages {
  display: flex;
  overflow-x: auto;
  border: 2px solid var(--steel);
  background: var(--panel-2);
  scrollbar-width: thin;
}

.page-about .stages__seg {
  position: relative;
  flex: 1 0 clamp(140px, 19%, 260px);
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 20px 16px 18px;
  border-right: var(--line);
  transition: background-color var(--t-fast);
}

.page-about .stages__seg:last-child {
  border-right: 0;
}

.page-about .stages__seg::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 4px;
  background: var(--cyan);
}

.page-about .stages__seg--violet::before {
  background: var(--violet);
}

.page-about .stages__seg--amber::before {
  background: var(--amber);
}

.page-about .stages__seg:hover {
  background: var(--panel);
}

.page-about .stages__no {
  font-size: 12px;
  color: var(--note-dim);
}

.page-about .stages__name {
  font-size: 15px;
  font-weight: 700;
  color: var(--headline);
}

.page-about .stages__meta {
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--note);
}

/* ---------- 服务点体系 ---------- */
.page-about .net {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--about-gap);
  align-items: start;
}

.page-about .net__figure {
  margin: 0;
  border: 2px solid var(--steel);
  background: var(--panel);
}

.page-about .net__figure .media__img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

.page-about .net__side {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.page-about .net__stat {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 16px 18px;
  border: 2px solid var(--steel);
  background: var(--panel);
  box-shadow: var(--shadow-mid);
}

.page-about .net__stat .stat__num {
  font-family: var(--mono);
  font-size: clamp(34px, 4.4vw, 56px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--cyan);
}

.page-about .net__stat .stat__label {
  font-size: 13px;
  color: var(--note);
}

.page-about .net__kv {
  margin: 0;
  border-top: var(--line);
}

.page-about .net__kv .kv__row {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  padding: 10px 0;
  border-bottom: var(--line);
}

.page-about .net__kv .kv__key {
  font-size: 13px;
  color: var(--note);
}

.page-about .net__kv .kv__val {
  margin: 0;
  font-size: 13px;
  color: var(--headline);
}

.page-about .tiers {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--about-gap);
  margin-top: var(--about-gap);
}

.page-about .tier {
  padding: clamp(18px, 2.4vw, 28px);
  border-left: 3px solid var(--violet);
  background: var(--panel);
  transition: border-color var(--t-fast), background-color var(--t-fast);
}

.page-about .tier:hover {
  border-left-color: var(--cyan);
  background: var(--panel-2);
}

.page-about .tier__no {
  margin: 0 0 8px;
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--violet);
}

.page-about .tier:hover .tier__no {
  color: var(--cyan);
}

.page-about .tier__title {
  margin: 0 0 10px;
  font-size: 19px;
  font-weight: 700;
  color: var(--headline);
}

.page-about .tier__text {
  margin: 0;
  font-size: 15px;
  line-height: 1.85;
}

/* ---------- 行业场景 ---------- */
.page-about .sectors {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 0;
  border-top: var(--line);
}

.page-about .sector {
  position: relative;
  padding: clamp(18px, 2.4vw, 26px) clamp(16px, 2vw, 24px) clamp(18px, 2.4vw, 26px) clamp(18px, 2.6vw, 30px);
  border-bottom: var(--line);
  transition: background-color var(--t-fast), box-shadow var(--t-fast);
}

.page-about .sector::before {
  content: "";
  position: absolute;
  inset: 0 auto 0 0;
  width: 3px;
  background: transparent;
  transition: background-color var(--t-fast);
}

.page-about .sector:hover {
  background: var(--panel);
}

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

.page-about .sector__no {
  display: block;
  margin-bottom: 8px;
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--violet);
}

.page-about .sector__title {
  margin: 0 0 8px;
  font-size: 18px;
  font-weight: 700;
  color: var(--headline);
}

.page-about .sector__text {
  margin: 0;
  font-size: 15px;
  line-height: 1.8;
}

.page-about .sectors__figure {
  margin: clamp(24px, 3vw, 40px) 0 0;
  border: 2px solid var(--steel);
  background: var(--panel);
}

.page-about .sectors__figure .media__img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

/* ---------- 表格 ---------- */
.page-about .table-scroll {
  overflow-x: auto;
  border: 2px solid var(--steel);
  background: var(--panel);
  scrollbar-width: thin;
}

.page-about .data-table {
  width: 100%;
  min-width: 560px;
  border-collapse: collapse;
  font-size: 15px;
}

.page-about .data-table th,
.page-about .data-table td {
  text-align: left;
  padding: 14px 16px;
  border-bottom: var(--line);
  border-right: var(--line);
  vertical-align: top;
  line-height: 1.7;
}

.page-about .data-table thead th {
  font-size: 12px;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--note-dim);
  background: var(--panel-2);
}

.page-about .data-table tbody th {
  font-weight: 600;
  color: var(--headline);
  white-space: nowrap;
}

.page-about .data-table tbody tr {
  transition: background-color var(--t-fast), box-shadow var(--t-fast);
}

.page-about .data-table tbody tr:hover {
  background: var(--panel-2);
  box-shadow: inset 3px 0 0 var(--cyan);
}

.page-about .data-table tr:last-child th,
.page-about .data-table tr:last-child td {
  border-bottom: 0;
}

.page-about .data-table__num {
  font-family: var(--mono);
  color: var(--amber);
  white-space: nowrap;
}

/* ---------- 信息边界 ---------- */
.page-about .about-sec--narrow {
  max-width: 900px;
}

.page-about .bounds {
  margin: 0;
  padding: 0;
  list-style: none;
  border-top: var(--line);
}

.page-about .bounds__item {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 6px 20px;
  padding: 16px 0;
  border-bottom: var(--line);
}

.page-about .bounds__key {
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--cyan);
}

.page-about .bounds__item p {
  margin: 0;
  font-size: 15px;
  line-height: 1.85;
}

/* ---------- 相关入口 ---------- */
.page-about .about-next {
  margin-top: clamp(48px, 6.5vw, 92px);
  padding: clamp(20px, 2.8vw, 32px);
  border: 2px solid var(--steel);
  background: var(--panel-2);
}

.page-about .about-next__label {
  margin: 0 0 16px;
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--note-dim);
}

.page-about .about-next__links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

/* ---------- 响应式 ---------- */
@media (min-width: 720px) {
  .page-about .about-sec--narrow .bounds__item {
    grid-template-columns: 120px minmax(0, 1fr);
    align-items: baseline;
  }

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

  .page-about .sector {
    border-right: var(--line);
  }

  .page-about .sector:nth-child(2n) {
    border-right: 0;
  }

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

  .page-about .tl__item {
    grid-template-columns: var(--gauge-col) minmax(0, 1fr);
    gap: var(--about-gap);
  }

  .page-about .tl__item--band {
    grid-template-columns: minmax(0, 1fr);
  }

  .page-about .tl__axis {
    flex-direction: column;
    align-items: flex-start;
    gap: 8px;
    padding-left: 18px;
    border-left: 2px solid var(--steel);
    transition: border-color var(--t-fast);
  }

  .page-about .tl__item:hover .tl__axis,
  .page-about .tl__item:focus-within .tl__axis {
    border-left-color: var(--cyan);
  }

  .page-about .tl__copy {
    margin-left: 0;
    margin-top: 6px;
  }

  .page-about .about-head {
    grid-template-columns: minmax(0, 1fr) clamp(64px, 8vw, 104px);
    align-items: stretch;
  }

  .page-about .about-head__gauge {
    flex-direction: column;
    justify-content: space-between;
    align-items: center;
    padding-top: 0;
    padding-left: 14px;
    border-top: 0;
    border-left: var(--line);
  }

  .page-about .about-head__gauge-line {
    width: 8px;
    height: auto;
    flex: 1;
    min-height: 90px;
    border-left: 1px solid var(--steel);
    background-image: repeating-linear-gradient(to bottom, var(--steel) 0 1px, transparent 1px 12px);
  }

  .page-about .net {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
  }
}

@media (min-width: 1100px) {
  .page-about .sectors {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .sector {
    border-right: var(--line);
  }

  .page-about .sector:last-child {
    border-right: 0;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about * {
    transition: none !important;
  }
}