.page-about {
  --about-w: 64ch;
  --about-hair: rgba(16, 24, 32, 0.14);
  padding-bottom: clamp(40px, 7vw, 88px);
}

.page-about .about-hero {
  display: grid;
  gap: clamp(24px, 4vw, 40px);
  padding: clamp(22px, 4vw, 48px) 0 clamp(24px, 4vw, 44px);
}

.page-about .about-hero__lead h1 {
  margin: 12px 0 0;
  max-width: 17ch;
  font-family: var(--font-display);
  font-size: clamp(32px, 7.4vw, 62px);
  line-height: 1.05;
  letter-spacing: -0.012em;
  color: var(--paper);
}

.page-about .about-hero .lede {
  margin: 18px 0 0;
  max-width: var(--about-w);
  font-size: clamp(15px, 1.6vw, 17px);
  line-height: 1.85;
  color: var(--paper-dim);
}

.page-about .about-hero .btn-group {
  margin-top: 26px;
}

.page-about .about-hero__side {
  display: flex;
  flex-direction: column;
  gap: 12px;
  padding: 20px;
  border: 1px solid var(--line);
  background: linear-gradient(162deg, rgba(12, 38, 57, 0.92), rgba(6, 24, 38, 0.86));
  border-radius: var(--radius);
}

.page-about .about-hero__side-label {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--cyan);
}

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

.page-about .about-mini li {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 4px 8px;
  padding: 11px 0;
  border-bottom: 1px solid var(--line-soft);
}

.page-about .about-mini li:last-child {
  border-bottom: 0;
  padding-bottom: 0;
}

.page-about .about-mini .data-unit {
  font-size: 12px;
  color: var(--muted);
}

.page-about .about-jump {
  display: flex;
  flex-wrap: wrap;
  gap: 6px 24px;
  padding: 13px 0;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.page-about .about-jump a {
  color: var(--muted);
  text-decoration: none;
  padding: 2px 0;
  border-bottom: 1px solid transparent;
  transition: color 0.2s var(--ease), border-color 0.2s var(--ease);
}

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

.page-about .about-jump a:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 3px;
  color: var(--cyan);
}

.page-about .about-section {
  padding-top: clamp(36px, 6vw, 72px);
  scroll-margin-top: calc(var(--topbar-h) + 18px);
}

.page-about .about-head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 8px 18px;
  padding-bottom: 14px;
  margin-bottom: clamp(22px, 3.5vw, 40px);
  border-bottom: 1px solid var(--line);
}

.page-about .about-head__index {
  margin: 0;
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--cyan);
}

.page-about .about-head__title {
  flex: 1 1 300px;
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(23px, 3.4vw, 37px);
  line-height: 1.16;
  letter-spacing: -0.01em;
  color: var(--paper);
}

.page-about .about-head__note {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--muted);
}

/* ---------- 时间线 ---------- */
.page-about .about-history {
  display: grid;
  gap: clamp(24px, 3.5vw, 44px);
}

.page-about .timeline {
  list-style: none;
  margin: 0;
  padding: 0;
  position: relative;
}

.page-about .timeline::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 6px;
  bottom: 10px;
  width: 1px;
  background: linear-gradient(to bottom, rgba(53, 226, 210, 0.75), rgba(30, 64, 89, 0.4) 55%, rgba(30, 64, 89, 0.1));
}

.page-about .timeline__item {
  position: relative;
  padding: 0 0 clamp(20px, 3vw, 30px) 30px;
}

.page-about .timeline__item:last-child {
  padding-bottom: 0;
}

.page-about .timeline__node {
  position: absolute;
  left: 0;
  top: 6px;
  width: 11px;
  height: 11px;
  border-radius: 50%;
  border: 1px solid var(--line);
  background: var(--ink-900);
  transition: border-color 0.25s var(--ease), background-color 0.25s var(--ease), box-shadow 0.25s var(--ease);
}

.page-about .timeline__item:hover .timeline__node {
  border-color: var(--cyan);
  background: var(--cyan);
  box-shadow: 0 0 0 4px rgba(53, 226, 210, 0.14);
}

.page-about .timeline__meta {
  margin: 0 0 5px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--muted);
}

.page-about .timeline__meta .data-num {
  font-size: 12px;
  color: var(--cyan);
}

.page-about .timeline__title {
  margin: 0 0 6px;
  font-size: clamp(16px, 2vw, 19px);
  font-weight: 600;
  letter-spacing: 0.01em;
  color: var(--paper);
}

.page-about .timeline__text {
  margin: 0;
  max-width: 52ch;
  font-size: 15px;
  line-height: 1.82;
  color: var(--paper-dim);
}

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

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

/* ---------- 数据能力 ---------- */
.page-about .about-data {
  display: grid;
  gap: clamp(20px, 3vw, 32px);
}

.page-about .about-data__panel {
  padding: clamp(20px, 3vw, 34px);
}

.page-about .about-data__panel .prose {
  margin: 0 0 22px;
  max-width: 58ch;
  font-size: 15px;
  line-height: 1.85;
  color: var(--text);
}

.page-about .shift-list {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: 1px solid var(--about-hair);
}

.page-about .shift {
  display: grid;
  gap: 6px 16px;
  padding: 16px 0;
  border-bottom: 1px solid var(--about-hair);
}

.page-about .shift:last-child {
  border-bottom: 0;
  padding-bottom: 0;
}

.page-about .shift__tag {
  justify-self: start;
  align-self: start;
  padding: 3px 8px;
  border: 1px solid currentColor;
  border-radius: 2px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  color: #0F7C74;
}

.page-about .shift__tag--yellow {
  color: #8A6A05;
}

.page-about .shift__tag--red {
  color: #B02A34;
}

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

.page-about .shift__title {
  margin: 0 0 4px;
  font-size: 15px;
  font-weight: 600;
  color: var(--text);
}

.page-about .shift__text {
  margin: 0;
  font-size: 14px;
  line-height: 1.78;
  color: #3A4550;
}

.page-about .about-side {
  display: grid;
  gap: 14px;
  align-content: start;
}

.page-about .about-side .figure {
  margin: 0;
}

.page-about .about-side__note {
  margin: 0;
  padding-left: 14px;
  border-left: 2px solid var(--orange);
  font-size: 13px;
  line-height: 1.75;
  color: var(--muted);
}

/* ---------- 覆盖范围 ---------- */
.page-about .reach-grid {
  display: grid;
  gap: 1px;
  margin-bottom: clamp(20px, 3vw, 32px);
  border: 1px solid var(--line);
  background: var(--line);
}

.page-about .reach-stat {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: clamp(18px, 2.6vw, 28px);
  background: var(--ink-900);
}

.page-about .reach-stat .data-num {
  line-height: 1;
}

.page-about .reach-stat .data-unit {
  font-size: 12px;
  color: var(--muted);
  margin-top: -2px;
}

.page-about .reach-stat__label {
  margin: 6px 0 0;
  font-size: 14px;
  font-weight: 600;
  color: var(--paper);
}

.page-about .reach-stat__text {
  margin: 0;
  font-size: 13px;
  line-height: 1.75;
  color: var(--muted);
}

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

/* ---------- 服务承诺 ---------- */
.page-about .promise {
  display: grid;
  gap: clamp(22px, 3vw, 36px);
}

.page-about .promise__body .prose {
  margin: 0 0 20px;
  max-width: 58ch;
  font-size: 15px;
  line-height: 1.85;
  color: var(--paper-dim);
}

.page-about .promise__list {
  list-style: none;
  display: grid;
  gap: 12px;
  margin: 0 0 26px;
  padding: 0;
}

.page-about .promise__list li {
  position: relative;
  padding-left: 20px;
  font-size: 14.5px;
  line-height: 1.82;
  color: var(--paper-dim);
}

.page-about .promise__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 11px;
  width: 7px;
  height: 1px;
  background: var(--cyan);
}

.page-about .promise__card {
  align-self: start;
  padding: clamp(18px, 2.6vw, 26px);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: linear-gradient(165deg, rgba(12, 38, 57, 0.95), rgba(6, 24, 38, 0.7));
}

.page-about .promise__card-title {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--cyan);
}

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

.page-about .promise__card-list li {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 12px;
  padding: 11px 0;
  border-bottom: 1px solid var(--line-soft);
  font-size: 13px;
  color: var(--paper-dim);
}

.page-about .promise__card-list li:last-child {
  border-bottom: 0;
  padding-bottom: 0;
}

.page-about .promise__card-list .data-num {
  font-size: 13px;
  color: var(--orange);
  white-space: nowrap;
}

@media (min-width: 560px) {
  .page-about .shift {
    grid-template-columns: 68px minmax(0, 1fr);
  }
}

@media (min-width: 760px) {
  .page-about .reach-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

@media (min-width: 900px) {
  .page-about .about-hero {
    grid-template-columns: minmax(0, 1.4fr) minmax(240px, 0.62fr);
    align-items: end;
  }

  .page-about .promise {
    grid-template-columns: minmax(0, 1.42fr) minmax(0, 1fr);
    align-items: start;
  }
}

@media (min-width: 980px) {
  .page-about .about-history,
  .page-about .about-data {
    grid-template-columns: minmax(0, 1.5fr) minmax(0, 1fr);
    align-items: start;
  }

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

@media (prefers-reduced-motion: reduce) {
  .page-about .about-jump a,
  .page-about .timeline__node {
    transition: none;
  }

  .page-about .timeline__item:hover .timeline__node {
    box-shadow: none;
  }
}