.page-about {
  --about-line: rgba(233, 241, 236, 0.14);
  --about-line-lime: rgba(200, 245, 60, 0.28);
  --about-pad: clamp(18px, 4vw, 42px);
  --about-sticky: 88px;
  background: var(--ink);
  color: var(--fog);
  overflow-x: clip;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding: clamp(20px, 4vw, 40px) 0 clamp(36px, 6vw, 72px);
  background:
    radial-gradient(circle at 78% -10%, rgba(200, 245, 60, 0.10), transparent 58%),
    radial-gradient(circle at 8% 110%, rgba(88, 182, 232, 0.08), transparent 52%),
    var(--ink);
}

.page-about .about-crumb {
  display: flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-num);
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--moss);
  margin-bottom: clamp(20px, 4vw, 36px);
}

.page-about .about-crumb a {
  color: var(--moss);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color 0.2s var(--ease), border-color 0.2s var(--ease);
}

.page-about .about-crumb a:hover,
.page-about .about-crumb a:focus-visible {
  color: var(--lime-soft);
  border-bottom-color: var(--line-lime-strong);
}

.page-about .about-crumb__sep {
  color: rgba(233, 241, 236, 0.24);
}

.page-about .about-hero__frame {
  position: relative;
  border: 1px solid var(--about-line);
  padding: clamp(22px, 4.4vw, 56px);
  border-radius: var(--radius);
  background: linear-gradient(180deg, rgba(22, 56, 47, 0.55), rgba(10, 14, 13, 0.2));
}

.page-about .about-hero__frame::before,
.page-about .about-hero__frame::after {
  content: "";
  position: absolute;
  height: 2px;
  width: 72px;
  background: var(--lime);
}

.page-about .about-hero__frame::before {
  top: -1px;
  left: -1px;
}

.page-about .about-hero__frame::after {
  bottom: -1px;
  right: -1px;
}

.page-about .about-eyebrow {
  margin: 0 0 14px;
  font-family: var(--font-num);
  font-size: 11px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--lime);
}

.page-about .about-hero__title {
  margin: 0 0 clamp(16px, 2.6vw, 26px);
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(34px, 7.4vw, 78px);
  line-height: 1.02;
  letter-spacing: -0.02em;
  color: var(--fog);
}

.page-about .about-hero__lead {
  margin: 0;
  max-width: 60ch;
  font-size: clamp(14px, 1.6vw, 17px);
  line-height: 1.8;
  color: rgba(233, 241, 236, 0.82);
}

.page-about .about-stats {
  list-style: none;
  margin: clamp(26px, 4vw, 44px) 0 0;
  padding: 1px;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--about-line);
  border: 1px solid var(--about-line);
}

.page-about .about-stats li {
  background: var(--ink-2);
  padding: 14px 16px;
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.page-about .about-stats__num {
  font-family: var(--font-num);
  font-size: clamp(22px, 3.2vw, 32px);
  letter-spacing: 0.04em;
  color: var(--lime);
  line-height: 1.1;
}

.page-about .about-stats__num em {
  font-style: normal;
  font-size: 0.62em;
  margin-left: 2px;
  color: var(--lime-soft);
}

.page-about .about-stats__k {
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--moss);
}

/* ---------- 主体分栏 ---------- */
.page-about .about-body {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(18px, 3vw, 28px);
  padding: clamp(24px, 4vw, 48px) 0 clamp(48px, 8vw, 96px);
  align-items: start;
}

.page-about .about-flow {
  display: grid;
  gap: clamp(16px, 2.4vw, 26px);
  min-width: 0;
}

/* ---------- 左侧章节导航 ---------- */
.page-about .about-nav {
  border: 1px solid var(--about-line);
  border-radius: var(--radius);
  background: rgba(15, 43, 36, 0.8);
  padding: 12px 14px;
  overflow-x: auto;
  scrollbar-width: thin;
}

.page-about .about-nav__label {
  margin: 0 0 10px;
  font-family: var(--font-num);
  font-size: 10px;
  letter-spacing: 0.2em;
  color: var(--moss);
  white-space: nowrap;
}

.page-about .about-nav__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  gap: 14px;
}

.page-about .about-nav__list li {
  flex: 0 0 auto;
}

.page-about .about-nav__list a {
  display: inline-flex;
  align-items: baseline;
  gap: 6px;
  font-size: 13px;
  line-height: 1.5;
  color: var(--fog);
  text-decoration: none;
  white-space: nowrap;
  padding-bottom: 3px;
  border-bottom: 1px solid transparent;
  transition: color 0.2s var(--ease), border-color 0.2s var(--ease);
}

.page-about .about-nav__list a:hover,
.page-about .about-nav__list a:focus-visible {
  color: var(--lime);
  border-bottom-color: var(--lime);
}

.page-about .about-nav__no {
  font-family: var(--font-num);
  font-size: 10px;
  letter-spacing: 0.14em;
  color: var(--moss);
}

.page-about .about-nav__back {
  display: none;
}

/* ---------- 章节通用 ---------- */
.page-about .about-chapter {
  border: 1px solid var(--about-line);
  border-radius: var(--radius);
  padding: var(--about-pad);
  min-width: 0;
}

.page-about .about-chapter--dark {
  background: var(--ink-2);
  color: var(--fog);
}

.page-about .about-chapter--paper {
  background: var(--paper);
  color: var(--ink-text);
  border-color: var(--paper-line);
}

.page-about .about-chapter__title {
  margin: 0 0 clamp(14px, 2vw, 20px);
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(23px, 3.4vw, 38px);
  line-height: 1.14;
  letter-spacing: -0.015em;
}

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

.page-about .about-chapter p {
  margin: 0 0 14px;
  max-width: 64ch;
  font-size: 14.5px;
  line-height: 1.8;
}

.page-about .about-chapter--dark p {
  color: rgba(233, 241, 236, 0.84);
}

.page-about .about-chapter--paper p {
  color: rgba(18, 26, 23, 0.84);
}

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

/* ---------- 展签 ---------- */
.page-about .about-tag {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 16px;
  padding: 5px 10px;
  border: 1px solid var(--about-line-lime);
  border-radius: var(--radius);
  font-family: var(--font-num);
  font-size: 10.5px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--lime);
}

.page-about .about-tag__no {
  color: var(--lime-soft);
}

.page-about .about-tag--paper {
  border-color: rgba(18, 26, 23, 0.28);
  background: rgba(217, 208, 190, 0.5);
  color: var(--ink-text);
}

.page-about .about-tag--paper .about-tag__no {
  color: rgba(18, 26, 23, 0.55);
}

/* ---------- 版本时间线 ---------- */
.page-about .about-track {
  position: relative;
  border: 1px solid var(--about-line);
  border-radius: var(--radius);
  background: linear-gradient(160deg, var(--ink-2), var(--ink) 72%);
  overflow: hidden;
}

.page-about .about-track__figure {
  margin: 0;
  position: relative;
  height: clamp(96px, 16vw, 150px);
  overflow: hidden;
  border-bottom: 1px solid var(--about-line);
}

.page-about .about-track__figure::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(10, 14, 13, 0.25), rgba(10, 14, 13, 0.92));
}

.page-about .about-track__figure img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.6;
}

.page-about .about-track__list {
  list-style: none;
  margin: 0;
  padding: clamp(18px, 3vw, 30px) var(--about-pad) clamp(20px, 3.4vw, 34px);
  display: grid;
  gap: 12px;
  grid-template-columns: minmax(0, 1fr);
}

.page-about .about-node {
  border-left: 2px solid rgba(200, 245, 60, 0.35);
  padding-left: 14px;
}

.page-about .about-node summary {
  cursor: pointer;
  list-style: none;
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 4px 0;
}

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

.page-about .about-node summary::marker {
  content: "";
}

.page-about .about-node__ver {
  font-family: var(--font-num);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--lime);
  flex: 0 0 auto;
}

.page-about .about-node__name {
  font-size: 14px;
  font-weight: 600;
  color: var(--fog);
  transition: color 0.2s var(--ease);
}

.page-about .about-node summary:hover .about-node__name,
.page-about .about-node summary:focus-visible .about-node__name {
  color: var(--lime-soft);
}

.page-about .about-node[open] {
  border-left-color: var(--lime);
}

.page-about .about-node p {
  margin: 4px 0 6px;
  font-size: 13.5px;
  line-height: 1.75;
  color: rgba(233, 241, 236, 0.78);
  max-width: 52ch;
}

/* ---------- 三件事 ---------- */
.page-about .about-list {
  list-style: none;
  margin: 6px 0 0;
  padding: 0;
  border-top: 1px solid var(--paper-line);
}

.page-about .about-list li {
  display: grid;
  grid-template-columns: 30px minmax(0, 1fr);
  column-gap: 12px;
  padding: clamp(16px, 2.4vw, 22px) 0;
  border-bottom: 1px solid var(--paper-line);
}

.page-about .about-list__no {
  font-family: var(--font-num);
  font-size: 12px;
  letter-spacing: 0.12em;
  color: #6b7a73;
  padding-top: 5px;
}

.page-about .about-list h3 {
  margin: 0 0 6px;
  font-size: clamp(16px, 2vw, 20px);
  font-weight: 700;
  line-height: 1.35;
  color: var(--ink-text);
}

.page-about .about-list p {
  grid-column: 2;
  margin: 0;
  font-size: 14px;
  line-height: 1.78;
  color: rgba(18, 26, 23, 0.82);
}

/* ---------- 团队 ---------- */
.page-about .about-team {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(20px, 3vw, 34px);
  align-items: start;
}

.page-about .about-crews {
  list-style: none;
  margin: 18px 0 0;
  padding: 0;
  display: grid;
  gap: 16px;
}

.page-about .about-crews li {
  border-top: 1px solid var(--about-line);
  padding-top: 12px;
}

.page-about .about-crews h3 {
  margin: 0 0 6px;
  font-size: 15px;
  font-weight: 700;
  letter-spacing: 0.02em;
  color: var(--lime-soft);
}

.page-about .about-crews p {
  margin: 0;
  font-size: 13.8px;
  line-height: 1.78;
  color: rgba(233, 241, 236, 0.8);
}

/* ---------- 图片 ---------- */
.page-about .about-figure {
  margin: 0;
}

.page-about .about-figure__frame {
  border: 1px solid var(--paper-line);
  background: var(--paper);
  padding: 10px;
  border-radius: var(--radius);
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  border-radius: 1px;
}

.page-about .about-figure--slant .about-figure__frame {
  clip-path: polygon(0 0, 100% 4%, 100% 100%, 0 96%);
}

.page-about .about-figure--slant img {
  aspect-ratio: 14 / 9;
}

.page-about .about-figure__cap {
  margin: 10px 0 0;
  font-family: var(--font-num);
  font-size: 10.5px;
  letter-spacing: 0.1em;
  line-height: 1.6;
  color: var(--moss);
}

.page-about .about-figure--wide {
  margin-bottom: clamp(18px, 3vw, 26px);
  border: 1px solid var(--about-line);
  background: var(--ink);
  padding: 8px;
  border-radius: var(--radius);
}

.page-about .about-figure--wide img {
  aspect-ratio: 3 / 2;
  max-height: 300px;
}

/* ---------- 数据节奏 ---------- */
.page-about .about-chapter--data {
  background:
    linear-gradient(180deg, rgba(22, 56, 47, 0.9), rgba(15, 43, 36, 0.96)),
    var(--ink-2);
}

.page-about .about-metrics {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--about-line);
  border: 1px solid var(--about-line);
  margin: 0 0 clamp(16px, 2.6vw, 24px);
}

.page-about .about-metrics__item {
  background: rgba(10, 14, 13, 0.55);
  padding: 14px 14px 16px;
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.page-about .about-metrics__num {
  font-family: var(--font-num);
  font-size: clamp(19px, 2.6vw, 26px);
  letter-spacing: 0.04em;
  line-height: 1.1;
  color: var(--lime);
}

.page-about .about-metrics__num em {
  font-style: normal;
  font-size: 0.55em;
  margin-left: 3px;
  letter-spacing: 0.08em;
  color: var(--lime-soft);
}

.page-about .about-metrics__item--warm .about-metrics__num {
  color: var(--orange);
}

.page-about .about-metrics__item--warm .about-metrics__num em {
  color: #ffc79c;
}

.page-about .about-metrics__k {
  font-size: 12px;
  line-height: 1.6;
  color: var(--moss);
}

/* ---------- 覆盖条形图 ---------- */
.page-about .about-chapter--coverage {
  background: var(--ink);
}

.page-about .about-bars {
  list-style: none;
  margin: clamp(16px, 2.6vw, 24px) 0 0;
  padding: 0;
  display: grid;
  gap: 2px;
}

.page-about .about-bars__item {
  display: grid;
  grid-template-columns: 76px minmax(0, 1fr);
  grid-template-areas:
    "name track"
    "tip  tip";
  gap: 6px 12px;
  align-items: center;
  padding: 10px 0;
  border-bottom: 1px solid var(--about-line);
}

.page-about .about-bars__name {
  grid-area: name;
  font-size: 13px;
  font-weight: 600;
  color: var(--fog);
  letter-spacing: 0.02em;
}

.page-about .about-bars__track {
  grid-area: track;
  display: block;
  height: 7px;
  background: rgba(233, 241, 236, 0.1);
  border-radius: 1px;
  overflow: hidden;
}

.page-about .about-bars__fill {
  display: block;
  height: 100%;
  background: linear-gradient(90deg, rgba(200, 245, 60, 0.55), var(--lime));
  transition: filter 0.2s var(--ease), transform 0.35s var(--ease);
  transform-origin: left center;
}

.page-about .about-bars__fill--1 { width: 94%; }
.page-about .about-bars__fill--2 { width: 80%; }
.page-about .about-bars__fill--3 { width: 63%; }
.page-about .about-bars__fill--4 { width: 52%; }
.page-about .about-bars__fill--5 { width: 44%; }
.page-about .about-bars__fill--6 {
  width: 31%;
  background: linear-gradient(90deg, rgba(126, 143, 136, 0.6), var(--moss));
}

.page-about .about-bars__tip {
  grid-area: tip;
  font-size: 12px;
  line-height: 1.6;
  color: var(--moss);
  transition: color 0.2s var(--ease);
}

.page-about .about-bars__item:hover .about-bars__tip,
.page-about .about-bars__item:focus-within .about-bars__tip {
  color: var(--lime-soft);
}

.page-about .about-bars__item:hover .about-bars__fill {
  filter: brightness(1.16);
}

.page-about .about-coverage__note {
  margin-top: clamp(14px, 2.2vw, 20px);
  font-size: 13.5px;
  line-height: 1.8;
  color: rgba(233, 241, 236, 0.74);
  max-width: 60ch;
}

/* ---------- 支持 ---------- */
.page-about .about-support {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  background: var(--paper-line);
  border: 1px solid var(--paper-line);
  margin: 4px 0 clamp(14px, 2.2vw, 20px);
}

.page-about .about-support__block {
  background: rgba(243, 238, 228, 0.6);
  padding: 14px 16px;
}

.page-about .about-support__num {
  display: block;
  font-family: var(--font-num);
  font-size: clamp(18px, 2.4vw, 24px);
  letter-spacing: 0.05em;
  color: var(--ink-text);
  margin-bottom: 6px;
}

.page-about .about-support__block p {
  margin: 0;
  font-size: 13px;
  line-height: 1.7;
  color: rgba(18, 26, 23, 0.78);
}

.page-about .about-link {
  display: inline-block;
  margin-top: clamp(12px, 2vw, 18px);
  font-size: 14px;
  font-weight: 600;
  color: var(--ink-text);
  text-decoration: none;
  border-bottom: 2px solid var(--orange);
  padding-bottom: 3px;
  transition: color 0.2s var(--ease), border-color 0.2s var(--ease);
}

.page-about .about-link:hover,
.page-about .about-link:focus-visible {
  color: #a24a08;
  border-bottom-color: var(--ink-text);
}

/* ---------- 尾部入口 ---------- */
.page-about .about-next {
  padding: clamp(36px, 6vw, 76px) 0 clamp(48px, 8vw, 96px);
  background:
    linear-gradient(180deg, var(--ink-2), var(--ink) 60%),
    var(--ink);
  border-top: 1px solid var(--about-line);
}

.page-about .about-next__title {
  margin: 0 0 clamp(20px, 3.4vw, 34px);
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(24px, 4vw, 42px);
  line-height: 1.16;
  letter-spacing: -0.015em;
  color: var(--fog);
  max-width: 20ch;
}

.page-about .about-next__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
}

.page-about .about-next__card {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: clamp(16px, 2.4vw, 24px);
  border: 1px solid var(--about-line);
  border-radius: var(--radius);
  background: rgba(22, 56, 47, 0.42);
  color: var(--fog);
  text-decoration: none;
  transition: border-color 0.2s var(--ease), background 0.2s var(--ease), transform 0.2s var(--ease);
}

.page-about .about-next__card:hover,
.page-about .about-next__card:focus-visible {
  border-color: var(--line-lime-strong);
  background: rgba(22, 56, 47, 0.82);
  transform: translateY(-2px);
}

.page-about .about-next__no {
  font-family: var(--font-num);
  font-size: 10.5px;
  letter-spacing: 0.18em;
  color: var(--lime);
}

.page-about .about-next__card strong {
  font-size: clamp(16px, 2vw, 19px);
  font-weight: 700;
  letter-spacing: 0.01em;
}

.page-about .about-next__card span:last-child {
  font-size: 13.5px;
  line-height: 1.72;
  color: rgba(233, 241, 236, 0.76);
}

/* ---------- 平板 ---------- */
@media (min-width: 640px) {
  .page-about .about-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

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

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

  .page-about .about-track__list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 16px 20px;
  }

  .page-about .about-bars__item {
    grid-template-columns: 88px minmax(0, 1fr) minmax(0, 1.1fr);
    grid-template-areas: "name track tip";
    gap: 12px;
  }
}

/* ---------- 桌面：展签长廊 ---------- */
@media (min-width: 920px) {
  .page-about .about-body {
    grid-template-columns: 208px minmax(0, 1fr);
    gap: clamp(28px, 4vw, 56px);
  }

  .page-about .about-nav {
    position: sticky;
    top: var(--about-sticky);
    overflow: visible;
    background: transparent;
    border: 0;
    border-top: 1px solid var(--line-lime-strong);
    border-radius: 0;
    padding: 16px 0 0;
  }

  .page-about .about-nav__label {
    color: var(--lime);
    margin-bottom: 14px;
  }

  .page-about .about-nav__list {
    display: grid;
    gap: 2px;
  }

  .page-about .about-nav__list a {
    display: flex;
    width: 100%;
    padding: 6px 0 6px 10px;
    border-bottom: 1px solid transparent;
    border-left: 2px solid transparent;
    font-size: 13px;
  }

  .page-about .about-nav__list a:hover,
  .page-about .about-nav__list a:focus-visible {
    border-bottom-color: transparent;
    border-left-color: var(--lime);
    color: var(--lime);
  }

  .page-about .about-nav__back {
    display: inline-block;
    margin-top: 20px;
    font-family: var(--font-num);
    font-size: 10.5px;
    letter-spacing: 0.16em;
    text-transform: uppercase;
    color: var(--moss);
    text-decoration: none;
    border-bottom: 1px solid var(--about-line);
    padding-bottom: 4px;
    transition: color 0.2s var(--ease), border-color 0.2s var(--ease);
  }

  .page-about .about-nav__back:hover,
  .page-about .about-nav__back:focus-visible {
    color: var(--lime);
    border-bottom-color: var(--lime);
  }

  .page-about .about-team {
    grid-template-columns: 1.1fr 0.9fr;
  }

  .page-about .about-figure--wide img {
    aspect-ratio: 3 / 1;
    max-height: 260px;
  }

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

  .page-about .about-chapter {
    padding: clamp(28px, 3.4vw, 48px);
  }
}

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

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