.page-about {
  --about-gap: clamp(16px, 3vw, 32px);
}

.page-about .about-top {
  padding-block: 18px 0;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  display: grid;
  gap: var(--about-gap);
  align-items: end;
  padding-block: clamp(22px, 4vw, 44px) clamp(26px, 4vw, 48px);
}

.page-about .about-hero__title {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(2.2rem, 8vw, 4.6rem);
  line-height: 1.04;
  letter-spacing: -0.02em;
  color: var(--text-hi);
  margin: 12px 0 18px;
}

.page-about .about-hero__lede {
  max-width: 62ch;
  color: var(--text-dim);
  font-size: clamp(1rem, 1.6vw, 1.125rem);
  margin: 0;
}

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

.page-about .about-note {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.08em;
  color: var(--text-dim);
  background: var(--ink-800);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 8px 12px;
  white-space: nowrap;
}

.page-about .about-note--hot {
  color: var(--orange);
  background: var(--orange-deep);
  border-color: var(--orange);
}

/* ---------- 数字条 ---------- */
.page-about .about-facts {
  padding-block: 0 clamp(20px, 3vw, 34px);
}

.page-about .about-facts__list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 0;
  padding: 0;
  list-style: none;
  background: var(--line);
  border: 2px solid var(--line);
}

.page-about .about-facts__item {
  display: flex;
  flex-direction: column;
  gap: 4px;
  background: var(--ink-800);
  padding: 16px 18px;
}

.page-about .about-facts__num {
  font-size: 1.55rem;
  font-weight: 700;
  line-height: 1.1;
  color: var(--cyan);
}

.page-about .about-facts__label {
  font-size: 0.8rem;
  color: var(--text-dim);
}

/* ---------- 服务范围 ---------- */
.page-about .scope-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
  margin-top: 26px;
}

.page-about .scope-card {
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: 20px;
  border-left-width: 4px;
  border-left-color: var(--cyan);
}

.page-about .scope-card:nth-child(2) {
  border-left-color: var(--orange);
}

.page-about .scope-card:nth-child(4) {
  border-left-color: var(--orange);
}

.page-about .scope-card h3 {
  margin: 0;
  font-size: 1.05rem;
  color: var(--text-hi);
  line-height: 1.4;
}

.page-about .scope-card p {
  margin: 0;
  font-size: 0.9rem;
  color: var(--text-dim);
}

.page-about .scope-card__for {
  margin-top: auto;
  padding-top: 12px;
  border-top: 1px dashed var(--line);
  font-size: 0.76rem;
  color: var(--text-hi);
}

/* ---------- 时间线 ---------- */
.page-about .tl-figure {
  margin: 26px 0 30px;
}

.page-about .tl {
  display: grid;
  gap: var(--about-gap);
}

.page-about .tl__years {
  display: flex;
  gap: 8px;
  margin: 0;
  padding: 0 0 6px;
  list-style: none;
  overflow-x: auto;
  scroll-snap-type: x proximity;
}

.page-about .tl__year {
  display: flex;
  flex-direction: column;
  gap: 2px;
  padding: 10px 14px;
  border: 2px solid var(--line);
  border-radius: var(--radius);
  background: var(--ink-800);
  color: var(--text-dim);
  text-decoration: none;
  white-space: nowrap;
  scroll-snap-align: start;
  transition: border-color 0.2s var(--ease), color 0.2s var(--ease);
}

.page-about .tl__year span {
  font-family: var(--font-mono);
  font-size: 1rem;
  color: var(--cyan);
}

.page-about .tl__year small {
  font-size: 0.72rem;
}

.page-about .tl__year:hover,
.page-about .tl__year:focus-visible {
  border-color: var(--cyan);
  color: var(--text-hi);
  outline: none;
}

.page-about .tl__list {
  display: grid;
  gap: 20px;
}

.page-about .tl__item {
  position: relative;
  padding-left: 22px;
  padding-bottom: 4px;
  border-left: 2px solid var(--line);
}

.page-about .tl__item::before {
  content: "";
  position: absolute;
  left: -8px;
  top: 16px;
  width: 12px;
  height: 12px;
  background: var(--ink-900);
  border: 2px solid var(--cyan);
}

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

.page-about .tl__card {
  padding: clamp(16px, 2.4vw, 24px);
}

.page-about .tl__stage {
  margin: 0 0 8px;
  font-size: 0.72rem;
  letter-spacing: 0.12em;
  color: var(--orange);
}

.page-about .tl__title {
  margin: 0 0 10px;
  font-size: clamp(1.1rem, 2vw, 1.35rem);
  line-height: 1.4;
  color: var(--text-hi);
}

.page-about .tl__card > p {
  margin: 0 0 12px;
  font-size: 0.94rem;
  color: var(--text-dim);
}

/* 折叠档案细节 */
.page-about .acc {
  border-top: 1px solid var(--line-soft);
  margin-top: 4px;
}

.page-about .acc__trigger {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  width: 100%;
  padding: 12px 0 10px;
  border: 0;
  background: none;
  color: var(--cyan);
  font-family: var(--font-body);
  font-size: 0.85rem;
  text-align: left;
  cursor: pointer;
}

.page-about .acc__trigger:hover {
  color: var(--text-hi);
}

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

.page-about .acc__icon {
  font-family: var(--font-mono);
  font-size: 1rem;
  transition: transform 0.2s var(--ease);
}

.page-about .acc__trigger[aria-expanded="true"] .acc__icon {
  transform: rotate(45deg);
}

.page-about .acc__panel {
  padding-bottom: 12px;
  font-size: 0.88rem;
  color: var(--text-dim);
}

.page-about .acc__panel ul {
  display: grid;
  gap: 6px;
  margin: 0;
  padding-left: 18px;
}

/* ---------- 移动端阅读 ---------- */
.page-about .reader {
  display: grid;
  gap: var(--about-gap);
  margin-top: 26px;
}

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

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

.page-about .reader__item {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 14px;
  padding: 14px 16px;
  background: var(--ink-800);
  border: 2px solid var(--line);
  border-left: 4px solid var(--cyan);
}

.page-about .reader__item:nth-child(2) {
  border-left-color: var(--text-dim);
}

.page-about .reader__item:nth-child(3) {
  border-left-color: var(--orange);
}

.page-about .reader__idx {
  font-size: 0.9rem;
  color: var(--cyan);
  padding-top: 2px;
}

.page-about .reader__item h3 {
  margin: 0 0 5px;
  font-size: 1rem;
  color: var(--text-hi);
}

.page-about .reader__item p {
  margin: 0;
  font-size: 0.88rem;
  color: var(--text-dim);
}

/* ---------- 四步路径 ---------- */
.page-about .steps {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
  margin: 26px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .step {
  padding: 22px 18px 18px;
  background: var(--ink-800);
  border: 2px solid var(--line);
  box-shadow: var(--shadow-hard);
}

.page-about .step__num {
  display: block;
  margin-bottom: 10px;
  font-size: 2rem;
  line-height: 1;
  color: var(--orange);
}

.page-about .step h3 {
  margin: 0 0 8px;
  font-size: 1rem;
  line-height: 1.4;
  color: var(--text-hi);
}

.page-about .step p {
  margin: 0;
  font-size: 0.87rem;
  color: var(--text-dim);
}

/* ---------- 服务分流 ---------- */
.page-about .support {
  display: grid;
  gap: var(--about-gap);
  margin-top: 26px;
}

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

.page-about .flow__box {
  fill: var(--ink-800);
  stroke: var(--line);
  stroke-width: 2;
  transition: stroke 0.2s var(--ease);
}

.page-about .flow__box--dst {
  fill: var(--ink-700);
}

.page-about .flow__node:hover .flow__box,
.page-about .flow__node:focus-within .flow__box {
  stroke: var(--cyan);
}

.page-about .flow__text {
  fill: var(--text-hi);
  font-family: var(--font-body);
  font-size: 18px;
  font-weight: 600;
}

.page-about .flow__sub {
  fill: var(--text-dim);
  font-family: var(--font-body);
  font-size: 14px;
}

.page-about .flow__line {
  fill: none;
  stroke: var(--orange);
  stroke-width: 2;
}

.page-about .flow__dot {
  fill: var(--cyan);
}

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

.page-about .support__item {
  padding: 4px 0 4px 14px;
  border-left: 3px solid var(--line);
}

.page-about .support__item strong {
  display: block;
  margin-bottom: 4px;
  font-size: 0.96rem;
  color: var(--text-hi);
}

.page-about .support__item span {
  font-size: 0.87rem;
  color: var(--text-dim);
}

.page-about .support__note {
  margin: 18px 0 0;
  padding-top: 14px;
  border-top: 1px dashed var(--line);
  font-size: 0.87rem;
  color: var(--text-dim);
}

/* ---------- 下一步 ---------- */
.page-about .about-next {
  padding-block: clamp(28px, 5vw, 56px);
}

.page-about .about-next__panel {
  display: grid;
  gap: 22px;
  padding: clamp(20px, 3.4vw, 36px);
  border-left: 4px solid var(--cyan);
}

.page-about .about-next__title {
  margin: 8px 0 10px;
  font-family: var(--font-display);
  font-size: clamp(1.35rem, 2.6vw, 2rem);
  line-height: 1.3;
  color: var(--text-hi);
}

.page-about .about-next__panel p {
  margin: 0;
  font-size: 0.93rem;
  color: var(--text-dim);
}

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

/* ---------- 响应式 ---------- */
@media (min-width: 720px) {
  .page-about .about-facts__list {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

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

@media (min-width: 900px) {
  .page-about .about-hero {
    grid-template-columns: minmax(0, 1fr) 132px;
    gap: clamp(24px, 4vw, 48px);
  }

  .page-about .about-hero__side {
    flex-direction: column;
    align-items: flex-end;
    padding-bottom: 8px;
  }

  .page-about .about-note {
    writing-mode: vertical-rl;
    text-orientation: mixed;
    padding: 14px 8px;
  }

  .page-about .tl {
    grid-template-columns: 188px minmax(0, 1fr);
    gap: clamp(24px, 4vw, 56px);
  }

  .page-about .tl__axis {
    position: sticky;
    top: 96px;
    align-self: start;
  }

  .page-about .tl__years {
    flex-direction: column;
    overflow: visible;
    padding-bottom: 0;
  }

  .page-about .reader {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
    align-items: start;
  }

  .page-about .support {
    grid-template-columns: minmax(0, 1.1fr) minmax(0, 0.9fr);
    align-items: start;
  }

  .page-about .about-next__panel {
    grid-template-columns: minmax(0, 1.1fr) minmax(0, 0.9fr);
    align-items: center;
  }

  .page-about .about-next__actions {
    justify-content: flex-end;
  }
}

@media (min-width: 1080px) {
  .page-about .scope-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

@media (prefers-reduced-motion: reduce) {
  .page-about .tl__year,
  .page-about .acc__icon,
  .page-about .flow__box {
    transition: none;
  }
}