.page-about {
  --about-sheet: rgba(11, 16, 32, .9);
  --about-inset: rgba(5, 6, 10, .55);
  display: block;
  padding-bottom: 4rem;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  display: grid;
  gap: 2rem;
  padding: 1.6rem 0 3rem;
  overflow: hidden;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  top: -30%;
  right: -12%;
  width: min(72vw, 560px);
  height: min(72vw, 560px);
  background: radial-gradient(circle at 32% 32%, rgba(47, 107, 255, .3), rgba(139, 92, 246, .14) 46%, transparent 72%);
  filter: blur(12px);
  pointer-events: none;
  z-index: 0;
}

.page-about .about-hero__copy {
  position: relative;
  z-index: 2;
}

.page-about .about-hero h1 {
  font-family: var(--font-display);
  font-size: clamp(2rem, 6.4vw, 3.9rem);
  line-height: 1.1;
  letter-spacing: -.02em;
  margin: .9rem 0 1rem;
  color: var(--text);
  text-wrap: balance;
}

.page-about .about-hero .lede {
  max-width: 46ch;
  color: var(--muted);
}

.page-about .about-facts {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(130px, 1fr));
  gap: 1rem;
  margin-top: 1.9rem;
  max-width: 560px;
}

.page-about .about-fact {
  border-left: 2px solid var(--line-soft);
  padding-left: .85rem;
  display: flex;
  flex-direction: column;
  gap: .25rem;
}

.page-about .about-fact .data-value {
  font-size: clamp(1.5rem, 4vw, 2.1rem);
}

.page-about .about-fact .data-label {
  font-size: .8rem;
  letter-spacing: .04em;
}

.page-about .about-hero__media {
  position: relative;
  z-index: 1;
  border: 1px solid var(--line-soft);
  clip-path: polygon(0 0, 100% 0, 100% 84%, 86% 100%, 0 100%);
  box-shadow: var(--shadow-card);
}

.page-about .about-hero__media img,
.page-about .media-frame img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.page-about .about-hero .v-note {
  position: absolute;
  right: .4rem;
  bottom: 1.2rem;
  z-index: 3;
}

/* ---------- 章节导航 ---------- */
.page-about .about-index {
  display: flex;
  gap: .5rem;
  overflow-x: auto;
  padding: .85rem 0;
  border-top: 1px solid var(--line-hair);
  border-bottom: 1px solid var(--line-hair);
  scrollbar-width: none;
}

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

.page-about .about-index a {
  flex: 0 0 auto;
  font-family: var(--font-data);
  font-size: .78rem;
  letter-spacing: .05em;
  color: var(--muted);
  text-decoration: none;
  padding: .38rem .78rem;
  border: 1px solid var(--line-hair);
  border-radius: 999px;
  transition: color .25s var(--ease), border-color .25s var(--ease), background .25s var(--ease);
}

.page-about .about-index a:hover,
.page-about .about-index a:focus-visible {
  color: var(--text);
  border-color: var(--blue);
  background: rgba(47, 107, 255, .14);
}

/* ---------- 章节骨架 ---------- */
.page-about .about-chapter {
  position: relative;
  display: grid;
  gap: 1.5rem;
  padding: 3rem 0;
  border-bottom: 1px solid var(--line-hair);
  scroll-margin-top: 6rem;
}

.page-about .about-chapter--last {
  border-bottom: 0;
}

.page-about .about-chapter__aside {
  display: flex;
  flex-direction: column;
  gap: .5rem;
}

.page-about .about-chapter__aside .chapter-index {
  font-family: var(--font-data);
  font-weight: 700;
  font-size: clamp(2.8rem, 9vw, 4.4rem);
  line-height: .9;
  color: rgba(47, 107, 255, .38);
  letter-spacing: -.03em;
}

.page-about .about-chapter__body > p {
  max-width: 68ch;
  color: var(--text);
}

.page-about .about-chapter__body > p + p {
  margin-top: 1rem;
}

.page-about .about-chapter__body > * + * {
  margin-top: 1.35rem;
}

.page-about .about-chapter .section-title {
  font-family: var(--font-display);
  font-size: clamp(1.5rem, 3.4vw, 2.3rem);
  line-height: 1.22;
  letter-spacing: -.01em;
  color: var(--text);
  margin: 0;
  text-wrap: balance;
}

.page-about .about-links {
  display: flex;
  flex-wrap: wrap;
  gap: .7rem;
}

/* ---------- 纸张叠层组件 ---------- */
.page-about .sheet {
  position: relative;
  background: var(--about-sheet);
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  padding: 1.3rem 1.25rem;
  box-shadow: var(--shadow-card);
}

.page-about .sheet::after {
  content: "";
  position: absolute;
  top: 9px;
  left: 9px;
  right: -9px;
  bottom: -9px;
  border: 1px dashed var(--line-hair);
  border-radius: var(--radius);
  pointer-events: none;
}

.page-about .sheet__inner {
  position: relative;
  z-index: 1;
}

.page-about .sheet__title {
  font-family: var(--font-data);
  font-size: .84rem;
  letter-spacing: .08em;
  text-transform: uppercase;
  color: var(--cyan);
  margin: 0 0 .9rem;
}

.page-about .ratio-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: .55rem;
}

.page-about .ratio-list li {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: .68rem .9rem;
  border: 1px solid var(--line-hair);
  border-radius: var(--radius-s);
  background: var(--about-inset);
  font-size: .95rem;
}

/* ---------- 三档区间 ---------- */
.page-about .range-block {
  border: 1px solid var(--line-hair);
  border-radius: var(--radius);
  padding: 1.2rem 1.15rem;
  background: linear-gradient(150deg, rgba(11, 16, 32, .92), rgba(5, 6, 10, .92));
}

.page-about .range-row {
  display: grid;
  gap: .7rem;
}

.page-about .range-item {
  display: flex;
  flex-direction: column;
  gap: .3rem;
  padding: .85rem 1rem;
  border-radius: var(--radius-s);
  border-left: 3px solid var(--blue);
  background: var(--about-inset);
}

.page-about .range-item--base {
  border-left-color: var(--blue);
}

.page-about .range-item--mid {
  border-left-color: var(--violet);
}

.page-about .range-item--high {
  border-left-color: var(--amber);
}

.page-about .range-item__name {
  font-family: var(--font-data);
  font-weight: 600;
  letter-spacing: .03em;
  color: var(--text);
}

.page-about .range-item__desc {
  font-size: .87rem;
  color: var(--muted);
  line-height: 1.6;
}

/* ---------- 六位编码拆解 ---------- */
.page-about .code-split {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: .6rem;
}

.page-about .code-split__seg {
  display: flex;
  flex-direction: column;
  gap: .35rem;
  padding: 1rem .8rem;
  border: 1px solid var(--line-soft);
  border-radius: var(--radius-s);
  background: var(--about-inset);
  font-family: var(--font-data);
  font-size: .78rem;
  color: var(--muted);
  text-align: center;
}

.page-about .code-split__seg b {
  font-size: .92rem;
  color: var(--text);
  letter-spacing: .02em;
}

.page-about .code-split__seg--season {
  border-top: 2px solid var(--blue);
}

.page-about .code-split__seg--area {
  border-top: 2px solid var(--violet);
}

.page-about .code-split__seg--table {
  border-top: 2px solid var(--cyan);
}

/* ---------- 运营坐标信息行 ---------- */
.page-about .meta-line {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: .6rem;
  padding: .8rem 1rem;
  border: 1px solid var(--line-hair);
  border-radius: var(--radius-s);
  background: var(--about-inset);
}

.page-about .meta-key {
  font-size: .8rem;
  letter-spacing: .06em;
  color: var(--muted);
  min-width: 5rem;
}

.page-about .meta-val {
  font-family: var(--font-data);
  font-size: .92rem;
  color: var(--amber);
  word-break: break-all;
}

/* ---------- 归档章节双列 ---------- */
.page-about .about-chapter__cols {
  display: grid;
  gap: 1.6rem;
}

.page-about .about-chapter__cols .media-frame {
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--about-inset);
}

.page-about .archive-accordion {
  display: grid;
  gap: .6rem;
}

.page-about .archive-accordion .accordion {
  border: 1px solid var(--line-hair);
  border-radius: var(--radius-s);
  background: var(--about-inset);
  padding: .2rem .9rem;
}

/* ---------- 合作生态 ---------- */
.page-about .eco-layout {
  display: grid;
  gap: 1.6rem;
}

.page-about .eco-grid {
  display: grid;
  gap: .85rem;
}

.page-about .eco-node {
  position: relative;
  border: 1px solid var(--line-hair);
  border-radius: var(--radius);
  background: linear-gradient(160deg, rgba(11, 16, 32, .92), rgba(5, 6, 10, .92));
  padding: 1.15rem 1.15rem 1.2rem;
  transition: transform .3s var(--ease), border-color .3s var(--ease), box-shadow .3s var(--ease);
}

.page-about .eco-node:hover,
.page-about .eco-node:focus-within {
  transform: translateY(-5px);
  border-color: var(--blue);
  box-shadow: var(--shadow-glow);
}

.page-about .eco-node__idx {
  display: block;
  font-family: var(--font-data);
  font-size: .82rem;
  letter-spacing: .16em;
  color: var(--amber);
  margin-bottom: .5rem;
}

.page-about .eco-node h3 {
  font-family: var(--font-display);
  font-size: 1.05rem;
  margin: 0 0 .45rem;
  color: var(--text);
}

.page-about .eco-node p {
  margin: 0;
  font-size: .89rem;
  line-height: 1.65;
  color: var(--muted);
}

.page-about .eco-figure {
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--about-inset);
}

/* ---------- 结尾行动区 ---------- */
.page-about .about-cta {
  margin-top: 2.6rem;
  display: grid;
  gap: 1.4rem;
  padding: 1.7rem 1.4rem;
  border: 1px solid var(--line-soft);
  border-radius: var(--radius-l);
  background:
    radial-gradient(circle at 12% 20%, rgba(47, 107, 255, .2), transparent 58%),
    linear-gradient(140deg, rgba(11, 16, 32, .96), rgba(5, 6, 10, .96));
}

.page-about .about-cta h2 {
  font-family: var(--font-display);
  font-size: clamp(1.4rem, 3.2vw, 2rem);
  line-height: 1.24;
  margin: .55rem 0 .6rem;
  color: var(--text);
}

.page-about .about-cta p {
  margin: 0;
  color: var(--muted);
  max-width: 52ch;
}

.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: .7rem;
}

/* ---------- 响应式 ---------- */
@media (max-width: 700px) {
  .page-about .about-hero .v-note {
    display: none;
  }

  .page-about .about-hero__media {
    clip-path: none;
  }

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

@media (min-width: 760px) {
  .page-about .about-hero {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, .95fr);
    align-items: center;
    gap: 2.6rem;
    padding: 2.6rem 0 4.2rem;
  }

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

  .page-about .about-chapter__cols {
    grid-template-columns: minmax(0, 1fr) minmax(0, .85fr);
    align-items: start;
  }

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

  .page-about .about-cta {
    grid-template-columns: minmax(0, 1.2fr) minmax(0, .8fr);
    align-items: center;
    padding: 2.2rem 2rem;
  }
}

@media (min-width: 1000px) {
  .page-about .about-chapter {
    grid-template-columns: 190px minmax(0, 1fr);
    gap: 3rem;
    padding: 4.2rem 0;
  }

  .page-about .eco-layout {
    grid-template-columns: minmax(0, 1.35fr) minmax(0, .65fr);
    align-items: start;
  }

  .page-about .about-chapter__aside {
    position: sticky;
    top: 6.5rem;
    align-self: start;
  }
}