.page-about {
  --about-line: rgba(11, 42, 74, 0.14);
  --about-hl: rgba(242, 184, 75, 0.6);
  background: linear-gradient(180deg, var(--paper) 0%, var(--mist) 100%);
  color: var(--ink);
  overflow-x: hidden;
}

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

.page-about .about-crumbs .breadcrumbs__list {
  font-size: 12px;
  letter-spacing: 0.02em;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding: 20px 0 40px;
}

.page-about .about-hero__inner {
  display: grid;
  gap: 28px;
}

.page-about .about-hero__title {
  margin: 12px 0 0;
  font-family: var(--font-title);
  font-weight: 900;
  font-size: clamp(32px, 8vw, 64px);
  line-height: 1.08;
  letter-spacing: -0.02em;
  color: var(--deep);
  max-width: 15ch;
}

.page-about .about-hl {
  background: linear-gradient(transparent 62%, var(--about-hl) 62%);
}

.page-about .about-hero__lead {
  margin: 18px 0 0;
  max-width: 46ch;
  font-size: 16px;
  line-height: 1.8;
  color: var(--ink);
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 24px;
}

.page-about .about-hero__figure {
  margin: 0;
  overflow: hidden;
  background: linear-gradient(150deg, var(--deep), var(--tide) 55%, var(--water));
  border-radius: var(--radius-card);
}

.page-about .about-hero__figure img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
  mix-blend-mode: luminosity;
  opacity: 0.92;
}

.page-about .about-hero__caption {
  padding: 14px 20px 18px;
  font-family: var(--font-mono);
  font-size: 12px;
  line-height: 1.6;
  color: var(--paper);
  letter-spacing: 0.02em;
}

/* ---------- 章节锚点条 ---------- */
.page-about .about-anchors {
  border-top: 1px solid var(--about-line);
  border-bottom: 1px solid var(--about-line);
  background: rgba(251, 248, 242, 0.7);
}

.page-about .about-anchors__inner {
  display: flex;
  gap: 8px;
  padding-top: 10px;
  padding-bottom: 10px;
  overflow-x: auto;
  scrollbar-width: none;
}

.page-about .about-anchors__inner::-webkit-scrollbar {
  display: none;
}

.page-about .about-anchors__link {
  flex: 0 0 auto;
  padding: 7px 14px;
  border: 1px solid var(--about-line);
  border-radius: var(--radius-pill);
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--deep);
  text-decoration: none;
  transition: border-color 160ms var(--ease), background-color 160ms var(--ease), color 160ms var(--ease);
}

.page-about .about-anchors__link:hover,
.page-about .about-anchors__link:focus-visible {
  background: var(--deep);
  border-color: var(--deep);
  color: var(--paper);
}

/* ---------- 章节通用骨架 ---------- */
.page-about .about-chapter {
  padding: 44px 0;
  scroll-margin-top: 96px;
}

.page-about .about-chapter--alt {
  background: rgba(234, 243, 248, 0.75);
  border-top: 1px solid var(--about-line);
  border-bottom: 1px solid var(--about-line);
}

.page-about .about-chapter__inner {
  display: grid;
  gap: 18px;
}

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

.page-about .about-num {
  font-size: 34px;
  font-weight: 700;
  line-height: 1;
  color: var(--coral);
  letter-spacing: -0.04em;
}

.page-about .about-vertical {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.3em;
  color: var(--slate);
  padding-left: 10px;
  border-left: 1px solid var(--about-line);
}

.page-about .about-chapter__title {
  margin: 0 0 16px;
  font-family: var(--font-title);
  font-weight: 900;
  font-size: clamp(24px, 5vw, 38px);
  line-height: 1.2;
  letter-spacing: -0.01em;
  color: var(--deep);
  max-width: 18ch;
}

.page-about .about-chapter__body p {
  margin: 0 0 16px;
  max-width: 60ch;
  font-size: 15.5px;
  line-height: 1.85;
}

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

/* ---------- 要点列表 ---------- */
.page-about .about-points {
  list-style: none;
  margin: 22px 0 0;
  padding: 0;
  display: grid;
  gap: 12px;
  max-width: 60ch;
}

.page-about .about-points li {
  padding: 14px 16px;
  border-left: 3px solid var(--water);
  background: var(--paper);
  border-radius: 0 var(--radius-tag) var(--radius-tag) 0;
  font-size: 14.5px;
  line-height: 1.75;
}

.page-about .about-points strong {
  color: var(--deep);
  font-weight: 700;
  margin-right: 4px;
}

/* ---------- 文档方向卡 ---------- */
.page-about .about-doc-grid {
  display: grid;
  gap: 14px;
  margin-top: 24px;
}

.page-about .about-doc {
  padding: 20px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.page-about .about-doc__title {
  margin: 0;
  font-family: var(--font-title);
  font-size: 17px;
  font-weight: 700;
  color: var(--deep);
}

.page-about .about-doc p {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--ink);
}

.page-about .about-aside {
  margin-top: 20px !important;
  padding: 12px 16px;
  border: 1px dashed var(--about-line);
  border-radius: var(--radius-tag);
  font-size: 13.5px !important;
  line-height: 1.7;
  color: var(--tide);
  max-width: 60ch;
}

.page-about .about-aside--link {
  border-style: solid;
  border-color: var(--coral);
  background: var(--paper);
}

.page-about .about-aside .mono {
  color: var(--coral);
  font-weight: 600;
}

/* ---------- 团队折叠档案 ---------- */
.page-about .about-team {
  display: grid;
  gap: 12px;
  margin-top: 22px;
  max-width: 62ch;
}

.page-about .about-folder {
  padding: 0;
  overflow: hidden;
}

.page-about .about-folder summary {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  padding: 16px 18px;
  cursor: pointer;
  list-style: none;
  border-radius: var(--radius-card);
  transition: background-color 160ms var(--ease);
}

.page-about .about-folder summary::-webkit-details-marker {
  display: none;
}

.page-about .about-folder summary:hover {
  background: var(--mist);
}

.page-about .about-folder summary::after {
  content: "＋";
  font-family: var(--font-mono);
  font-size: 14px;
  color: var(--coral);
}

.page-about .about-folder[open] summary::after {
  content: "－";
}

.page-about .about-folder__name {
  font-family: var(--font-title);
  font-size: 16px;
  font-weight: 700;
  color: var(--deep);
}

.page-about .about-folder p {
  margin: 0;
  padding: 0 18px 18px;
  font-size: 14px;
  line-height: 1.8;
  color: var(--ink);
}

/* ---------- 图 ---------- */
.page-about .about-figure {
  margin: 26px 0 0;
  border: 1px solid var(--about-line);
  border-radius: var(--radius-card);
  overflow: hidden;
  background: var(--paper);
  box-shadow: var(--shadow-paper);
}

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

.page-about .about-figure figcaption {
  padding: 12px 16px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.02em;
  color: var(--slate);
  border-top: 1px solid var(--about-line);
}

/* ---------- 深色网络区 ---------- */
.page-about .about-chapter--dark {
  background: linear-gradient(160deg, var(--deep), var(--tide) 70%, var(--water));
  color: var(--paper);
}

.page-about .about-chapter--dark .about-chapter__title {
  color: var(--paper);
}

.page-about .about-chapter--dark .about-chapter__body p {
  color: rgba(251, 248, 242, 0.86);
}

.page-about .about-chapter--dark .about-vertical {
  color: rgba(251, 248, 242, 0.6);
  border-left-color: rgba(251, 248, 242, 0.28);
}

.page-about .about-nodes {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 22px;
}

.page-about .about-node {
  padding: 8px 14px;
  border: 1px solid rgba(251, 248, 242, 0.34);
  border-radius: var(--radius-pill);
  font-size: 12px;
  color: var(--paper);
  transition: border-color 160ms var(--ease), background-color 160ms var(--ease);
}

.page-about .about-node:hover {
  border-color: var(--gold);
  background: rgba(242, 184, 75, 0.14);
}

.page-about .about-node--core {
  background: var(--coral);
  border-color: var(--coral);
  color: var(--paper);
  font-weight: 700;
}

/* ---------- 时间轴 ---------- */
.page-about .about-timeline {
  list-style: none;
  margin: 26px 0 0;
  padding: 0;
  position: relative;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 8px;
  top: 8px;
  bottom: 8px;
  width: 2px;
  background: linear-gradient(180deg, var(--coral), var(--gold) 55%, var(--water));
}

.page-about .about-timeline__item {
  position: relative;
  padding: 0 0 26px 34px;
}

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

.page-about .about-timeline__item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 4px;
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: var(--paper);
  border: 2px solid var(--coral);
  box-sizing: border-box;
}

.page-about .about-timeline__item:hover::before {
  background: var(--gold);
  border-color: var(--gold);
}

.page-about .about-year {
  display: inline-block;
  font-size: 20px;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--deep);
}

.page-about .about-timeline__title {
  margin: 6px 0 4px;
  font-family: var(--font-title);
  font-size: 16px;
  font-weight: 700;
  color: var(--tide);
}

.page-about .about-timeline__item p {
  margin: 0;
  max-width: 50ch;
  font-size: 14px;
  line-height: 1.75;
  color: var(--ink);
}

/* ---------- 品牌色块 ---------- */
.page-about .about-swatches {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 22px;
}

.page-about .about-swatch {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0 18px;
  border-radius: var(--radius-tag);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
}

.page-about .about-swatch--deep {
  background: var(--deep);
  color: var(--paper);
}

.page-about .about-swatch--coral {
  background: var(--coral);
  color: var(--deep);
}

.page-about .about-swatch--gold {
  background: var(--gold);
  color: var(--deep);
}

.page-about .about-swatch--felt {
  background: var(--felt);
  color: var(--paper);
}

.page-about .about-swatch--water {
  background: var(--water);
  color: var(--paper);
}

/* ---------- 底部入口 ---------- */
.page-about .about-cta {
  padding: 40px 0 56px;
  background: var(--paper);
  border-top: 3px solid var(--coral);
}

.page-about .about-cta__inner {
  display: grid;
  gap: 24px;
}

.page-about .about-cta__title {
  margin: 0 0 12px;
  font-family: var(--font-title);
  font-weight: 900;
  font-size: clamp(22px, 4.6vw, 32px);
  line-height: 1.25;
  color: var(--deep);
}

.page-about .about-cta__lead p {
  margin: 0;
  max-width: 52ch;
  font-size: 15px;
  line-height: 1.8;
}

.page-about .about-cta__links {
  display: grid;
  gap: 10px;
}

.page-about .about-cta__item {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 14px 18px;
  border: 1px solid var(--about-line);
  border-radius: var(--radius-tag);
  background: var(--mist);
  font-family: var(--font-title);
  font-size: 15px;
  font-weight: 700;
  color: var(--deep);
  text-decoration: none;
  transition: border-color 160ms var(--ease), transform 160ms var(--ease), background-color 160ms var(--ease);
}

.page-about .about-cta__item .mono {
  font-size: 12px;
  font-weight: 400;
  color: var(--coral);
}

.page-about .about-cta__item:hover,
.page-about .about-cta__item:focus-visible {
  border-color: var(--coral);
  background: var(--paper);
  transform: translateY(-2px);
}

/* ---------- 平板与桌面 ---------- */
@media (min-width: 720px) {
  .page-about .about-hero {
    padding: 28px 0 56px;
  }

  .page-about .about-hero__inner {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.75fr);
    gap: 40px;
    align-items: start;
  }

  .page-about .about-hero__lead {
    font-size: 17px;
  }

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

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

  .page-about .about-chapter {
    padding: 60px 0;
  }
}

@media (min-width: 960px) {
  .page-about .about-chapter__inner {
    grid-template-columns: 96px minmax(0, 1fr);
    gap: 32px;
    align-items: start;
  }

  .page-about .about-chapter__marker {
    flex-direction: column;
    align-items: flex-start;
    gap: 16px;
    position: sticky;
    top: 96px;
  }

  .page-about .about-num {
    font-size: 46px;
  }

  .page-about .about-vertical {
    writing-mode: vertical-rl;
    padding: 10px 0 0;
    border-left: 0;
    border-top: 1px solid var(--about-line);
    letter-spacing: 0.4em;
  }

  .page-about .about-chapter--dark .about-vertical {
    border-top-color: rgba(251, 248, 242, 0.28);
  }

  .page-about .about-doc-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .about-doc-grid .about-doc:first-child {
    grid-column: span 2;
  }

  .page-about .about-figure {
    max-width: 720px;
  }

  .page-about .about-cta__inner {
    grid-template-columns: minmax(0, 0.85fr) minmax(0, 1fr);
    gap: 48px;
    align-items: center;
  }

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

  .page-about .about-year {
    font-size: 24px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-anchors__link,
  .page-about .about-node,
  .page-about .about-cta__item,
  .page-about .about-folder summary {
    transition: none;
  }

  .page-about .about-cta__item:hover,
  .page-about .about-cta__item:focus-visible {
    transform: none;
  }
}