/* ===== 品牌故事 · 页面专属样式（作用域 .page-about） ===== */

.page-about {
  --about-aside-w: 15.5rem;
  --about-gap: clamp(1.5rem, 4vw, 3.5rem);
  --about-rule: rgba(10, 74, 85, .14);
  background: var(--paper);
  color: var(--ink);
  overflow-x: clip;
  padding-bottom: clamp(2.5rem, 6vw, 5rem);
}

.page-about .about-wrap {
  padding-block: clamp(1.15rem, 3vw, 2rem) 0;
}

/* ---------- 首屏：非对称双栏 ---------- */

.page-about .about-hero {
  margin-block: clamp(1.75rem, 5vw, 3.25rem) clamp(2.5rem, 7vw, 5.5rem);
}

.page-about .about-hero__grid {
  display: grid;
  gap: clamp(1.75rem, 5vw, 3rem);
}

.page-about .about-hero__title {
  font-size: var(--fs-h1);
  font-weight: 800;
  line-height: 1.05;
  letter-spacing: -.02em;
  color: var(--lake-deep);
  margin-block: .55rem 1.15rem;
  max-width: 18ch;
}

.page-about .about-hero__lede {
  max-width: 40rem;
  color: var(--ink-soft);
  font-size: clamp(1rem, 1.45vw, 1.18rem);
  line-height: 1.85;
}

.page-about .about-hero__actions {
  margin-top: 1.6rem;
  margin-bottom: 0;
}

/* ---------- 首屏右侧：章节索引 ---------- */

.page-about .about-index {
  align-self: start;
  border-top: 3px solid var(--sand);
  padding-top: .95rem;
}

.page-about .about-index__head {
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--ink-soft);
  margin-bottom: .7rem;
}

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

.page-about .about-index__item {
  border-bottom: 1px solid var(--about-rule);
}

.page-about .about-index__link {
  display: flex;
  align-items: baseline;
  gap: .8rem;
  padding: .55rem .3rem;
  color: var(--ink);
  text-decoration: none;
  transition: background-color 160ms var(--ease), transform 160ms var(--ease);
}

.page-about .about-index__link:hover,
.page-about .about-index__link:focus-visible {
  background: var(--grape-mist);
  transform: translateX(3px);
}

.page-about .about-index__num {
  font-size: .8125rem;
  color: var(--grape);
  flex: none;
}

.page-about .about-index__text {
  font-size: .95rem;
}

/* ---------- 章节外壳 ---------- */

.page-about .about-flow {
  display: block;
}

.page-about .about-chapter {
  padding-block: clamp(2rem, 5vw, 3.5rem);
}

.page-about .about-band {
  display: flex;
  align-items: center;
  gap: 1rem;
  padding: .55rem 1.15rem;
  margin-bottom: clamp(1.15rem, 3vw, 2rem);
  border-radius: var(--r-organic-alt);
  color: var(--highlight);
  font-size: 12px;
  letter-spacing: .08em;
  transition: width 320ms var(--ease);
}

.page-about .about-band--deep { background: var(--lake-deep); }
.page-about .about-band--mid { background: var(--lake); }
.page-about .about-band--grape { background: var(--grape); }

.page-about .about-band__num {
  font-size: .8125rem;
  opacity: .82;
}

.page-about .about-band__label {
  font-weight: 600;
  letter-spacing: .18em;
}

/* 章节色带宽度逐章收窄，形成向前的动势 */
.page-about .about-flow > .about-chapter:nth-of-type(1) .about-band { width: 100%; }
.page-about .about-flow > .about-chapter:nth-of-type(2) .about-band { width: 93%; }
.page-about .about-flow > .about-chapter:nth-of-type(3) .about-band { width: 86%; }
.page-about .about-flow > .about-chapter:nth-of-type(4) .about-band { width: 79%; }
.page-about .about-flow > .about-chapter:nth-of-type(5) .about-band { width: 72%; }
.page-about .about-flow > .about-chapter:nth-of-type(6) .about-band { width: 65%; }

/* ---------- 正文与旁注 ---------- */

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

.page-about .about-col {
  max-width: 42rem;
  min-width: 0;
}

.page-about .about-col h2 {
  font-size: var(--fs-h2);
  font-weight: 800;
  line-height: 1.14;
  letter-spacing: -.02em;
  color: var(--lake-deep);
  margin-bottom: 1rem;
}

.page-about .about-col p {
  font-size: 1.0625rem;
  line-height: 1.85;
  color: var(--ink);
  margin-bottom: 1rem;
  max-width: 38rem;
}

.page-about .about-link {
  color: var(--grape);
  text-decoration: underline;
  text-decoration-color: rgba(91, 42, 110, .35);
  text-underline-offset: 3px;
}

.page-about .about-link:hover {
  text-decoration-color: var(--grape);
}

/* 旁注栏 */
.page-about .about-aside {
  border-top: 2px solid var(--lake);
  padding-top: .85rem;
}

.page-about .about-aside__head {
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--ink-soft);
  margin-bottom: .85rem;
}

.page-about .about-aside__row {
  border-bottom: 1px solid var(--about-rule);
}

.page-about .about-aside__link {
  display: flex;
  flex-direction: column;
  gap: .2rem;
  padding: .6rem 0;
  color: inherit;
  text-decoration: none;
  transition: transform 160ms var(--ease), color 160ms var(--ease);
}

.page-about .about-aside__link:hover,
.page-about .about-aside__link:focus-visible {
  color: var(--grape);
  transform: translateX(3px);
}

.page-about .about-aside__num {
  font-size: 1.4rem;
  line-height: 1.15;
  color: var(--lake);
  font-variant-numeric: tabular-nums;
}

.page-about .about-aside__label {
  font-size: .8125rem;
  line-height: 1.65;
  color: var(--ink-soft);
}

/* ---------- 三代结构演进图 ---------- */

.page-about .about-evo-wrap {
  margin-block: clamp(1.5rem, 4vw, 2.25rem);
  padding: clamp(.9rem, 3vw, 1.6rem);
  background: var(--highlight);
  border-radius: var(--r-organic);
  box-shadow: var(--shadow-card);
}

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

.page-about .about-evo__cap {
  margin: .85rem 0 0;
  font-size: .8125rem;
  line-height: 1.7;
  color: var(--ink-soft);
}

.page-about .evo-label {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: .06em;
  fill: var(--lake-deep);
}

.page-about .evo-fill-a { fill: var(--lake-mist); }
.page-about .evo-fill-b { fill: var(--grape-mist); }
.page-about .evo-fill-accent { fill: var(--sand); }
.page-about .evo-fill-deep { fill: var(--grape); }

.page-about .evo-link {
  fill: none;
  stroke: var(--grape);
  stroke-width: 1.5;
  stroke-dasharray: 5 5;
}

/* ---------- 图片容器 ---------- */

.page-about .about-figure {
  margin-block: clamp(1.5rem, 4vw, 2.25rem) 0;
}

.page-about .about-figure img {
  max-width: 100%;
  height: auto;
  object-fit: cover;
}

/* ---------- 联系信息表 ---------- */

.page-about .about-contact {
  margin: 1.6rem 0 0;
  border-top: 1px solid var(--about-rule);
}

.page-about .about-contact__row {
  display: grid;
  gap: .15rem .9rem;
  padding: .7rem 0;
  border-bottom: 1px solid var(--about-rule);
}

.page-about .about-contact__key {
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--ink-soft);
}

.page-about .about-contact__val {
  margin: 0;
  font-size: .95rem;
  color: var(--ink);
  overflow-wrap: anywhere;
}

.page-about .about-contact__val--mono {
  font-family: var(--font-mono);
  font-size: .875rem;
}

/* ---------- 结尾三件事 ---------- */

.page-about .about-chapter--closing .about-col {
  max-width: 46rem;
}

.page-about .about-values {
  list-style: none;
  margin: 1.4rem 0 0;
  padding: 0;
  display: grid;
  gap: .85rem;
}

.page-about .about-value {
  display: grid;
  grid-template-columns: 2.4rem minmax(0, 1fr);
  gap: .15rem .85rem;
  padding: .9rem 1rem .95rem 1.05rem;
  border-left: 4px solid var(--lake-mist);
  border-radius: 0 var(--r-organic) var(--r-organic) 0;
  background: linear-gradient(90deg, rgba(203, 226, 230, .45), rgba(245, 239, 227, 0));
  transition: border-color 160ms var(--ease), transform 160ms var(--ease);
}

.page-about .about-value:hover {
  transform: translateX(3px);
}

.page-about .about-value:nth-child(1) { border-left-color: var(--lake); }
.page-about .about-value:nth-child(2) { border-left-color: var(--grape); }
.page-about .about-value:nth-child(3) { border-left-color: var(--sand); }

.page-about .about-value__num {
  grid-row: span 2;
  font-size: .875rem;
  color: var(--grape);
  padding-top: .3rem;
}

.page-about .about-value__title {
  margin: 0;
  font-size: 1.125rem;
  font-weight: 700;
  letter-spacing: -.01em;
  color: var(--lake-deep);
}

.page-about .about-value__text {
  margin: 0;
  font-size: .9375rem;
  line-height: 1.7;
  color: var(--ink-soft);
  max-width: 34rem;
}

.page-about .about-cta {
  margin-top: 1.75rem;
  margin-bottom: 0;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: .85rem 1.25rem;
}

.page-about .about-cta__alt {
  font-size: .9rem;
  color: var(--ink-soft);
}

/* ---------- 平板及以上 ---------- */

@media (min-width: 46rem) {
  .page-about .about-contact__row {
    grid-template-columns: 7rem minmax(0, 1fr);
    align-items: baseline;
  }
}

/* ---------- 桌面：正文窄栏居左，旁注成列 ---------- */

@media (min-width: 60rem) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.6fr) minmax(15rem, 1fr);
    align-items: start;
    gap: clamp(2rem, 5vw, 4.5rem);
  }

  .page-about .about-body {
    grid-template-columns: minmax(0, 1fr) var(--about-aside-w);
    align-items: start;
  }

  .page-about .about-aside {
    position: sticky;
    top: 2rem;
  }

  .page-about .about-value {
    grid-template-columns: 2.4rem minmax(0, 1fr);
  }
}

/* ---------- 窄屏保护 ---------- */

@media (max-width: 25rem) {
  .page-about .about-band {
    width: 100% !important;
    letter-spacing: .1em;
  }

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

  .page-about .about-value__num {
    grid-row: auto;
    padding-top: 0;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-band,
  .page-about .about-index__link,
  .page-about .about-aside__link,
  .page-about .about-value {
    transition: none;
  }
}