.page-about {
  --about-max: 1240px;
  --about-pad: 20px;
  --about-line: rgba(21, 106, 138, 0.42);
  --about-line-soft: rgba(21, 106, 138, 0.26);
  background-color: var(--night);
  color: var(--cool);
  font-family: var(--font-sans);
  overflow-x: hidden;
}

/* ---------- 封面 ---------- */
.page-about .about-cover {
  position: relative;
  overflow: hidden;
  padding: 34px 0 42px;
  border-bottom: 1px solid var(--about-line);
  background:
    radial-gradient(120% 92% at 84% 4%, rgba(79, 209, 224, 0.20), transparent 58%),
    radial-gradient(92% 78% at 2% 104%, rgba(255, 106, 43, 0.16), transparent 64%),
    linear-gradient(158deg, #071A24 0%, #0E3A4F 58%, #071A24 100%);
}

.page-about .about-cover::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 1px;
  background: repeating-linear-gradient(90deg, rgba(185, 242, 39, 0.55) 0 2px, transparent 2px 26px);
  opacity: 0.45;
}

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

.page-about .about-crumbs {
  display: flex;
  flex-wrap: wrap;
  gap: 6px 10px;
  margin: 0 0 20px;
  font-family: var(--font-narrow);
  font-size: var(--step-12);
  letter-spacing: 0.08em;
  color: var(--cool-mid);
}

.page-about .about-crumbs .crumbs__item + .crumbs__item::before {
  content: "/";
  margin-right: 8px;
  color: var(--ridge);
}

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

.page-about .about-crumbs a:hover {
  color: var(--signal);
  border-bottom-color: var(--signal);
}

.page-about .about-cover__eyebrow {
  margin: 0;
  color: var(--signal);
}

.page-about .about-h1 {
  margin: 14px 0 0;
  font-family: var(--font-serif);
  font-size: clamp(2.05rem, 7.6vw, 4.35rem);
  line-height: 1.08;
  letter-spacing: -0.012em;
  color: var(--cool);
  max-width: 16em;
}

.page-about .about-lead {
  margin: 20px 0 0;
  max-width: 46em;
  font-size: var(--step-16);
  line-height: 1.75;
  color: var(--cool-mid);
}

.page-about .about-facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 34px 0 0;
  padding: 0;
  background: var(--about-line);
  border: 1px solid var(--about-line);
}

.page-about .about-facts__cell {
  background: rgba(7, 26, 36, 0.74);
  padding: 14px 14px 16px;
}

.page-about .about-facts__label {
  margin: 0;
  font-family: var(--font-narrow);
  font-size: var(--step-12);
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--cool-mid);
}

.page-about .about-facts__value {
  margin: 8px 0 0;
  font-family: var(--font-mono);
  font-size: 30px;
  line-height: 1;
  color: var(--amber);
}

.page-about .about-facts__unit {
  font-family: var(--font-sans);
  font-size: var(--step-14);
  color: var(--cool-mid);
}

.page-about .about-cover__foot {
  margin: 18px 0 0;
  font-family: var(--font-mono);
  font-size: var(--step-12);
  letter-spacing: 0.06em;
  color: var(--ridge);
}

/* ---------- 外壳与左侧刻度索引 ---------- */
.page-about .about-shell {
  max-width: var(--about-max);
  margin: 0 auto;
  padding: 0 var(--about-pad) 64px;
}

.page-about .about-index {
  padding: 20px 0 0;
}

.page-about .about-index__title {
  margin: 0;
  font-family: var(--font-narrow);
  font-size: var(--step-12);
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--cool-mid);
}

.page-about .about-index__list {
  display: flex;
  gap: 8px;
  margin: 12px 0 0;
  padding: 0 0 8px;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: thin;
}

.page-about .about-index__link {
  display: inline-flex;
  align-items: baseline;
  gap: 7px;
  white-space: nowrap;
  padding: 7px 11px;
  font-family: var(--font-narrow);
  font-size: var(--step-12);
  letter-spacing: 0.06em;
  color: var(--cool-mid);
  text-decoration: none;
  background: rgba(14, 58, 79, 0.55);
  border: 1px solid var(--about-line);
  border-radius: var(--radius);
  transition: color 0.2s, border-color 0.2s, background-color 0.2s;
}

.page-about .about-index__no {
  font-family: var(--font-mono);
  color: var(--ridge);
}

.page-about .about-index__link:hover {
  color: var(--signal);
  border-color: rgba(79, 209, 224, 0.6);
}

.page-about .about-index__link[aria-current="true"] {
  color: var(--amber);
  border-color: rgba(255, 106, 43, 0.65);
  background: rgba(255, 106, 43, 0.1);
}

/* ---------- 章节通用 ---------- */
.page-about .about-sec {
  padding: 48px 0 10px;
  border-top: 1px solid var(--about-line-soft);
}

.page-about .about-sec:first-child {
  border-top: none;
  padding-top: 34px;
}

.page-about .about-sec__head {
  margin: 0 0 26px;
}

.page-about .about-sec__head .eyebrow {
  margin: 0 0 10px;
  color: var(--signal);
}

.page-about .about-sec__title {
  margin: 0;
  font-family: var(--font-serif);
  font-size: clamp(1.5rem, 5.4vw, 2.4rem);
  line-height: 1.22;
  letter-spacing: -0.008em;
  color: var(--cool);
  max-width: 20em;
}

.page-about .about-sec__note {
  margin: 14px 0 0;
  max-width: 44em;
  font-size: var(--step-14);
  line-height: 1.75;
  color: var(--cool-mid);
}

/* ---------- 起点与定位 ---------- */
.page-about .about-cols {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 24px;
}

.page-about .about-cols__main p {
  margin: 0 0 16px;
  max-width: 40em;
  font-size: var(--step-16);
  line-height: 1.78;
  color: var(--cool);
}

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

.page-about .about-cols__side {
  padding: 18px 18px 20px;
  border-left: 2px solid rgba(185, 242, 39, 0.55);
  background: rgba(14, 58, 79, 0.44);
}

.page-about .about-cols__side-label {
  margin: 0;
  font-family: var(--font-narrow);
  font-size: var(--step-12);
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--lime);
}

.page-about .about-cols__side-text {
  margin: 10px 0 0;
  font-size: var(--step-14);
  line-height: 1.78;
  color: var(--cool-mid);
}

.page-about .about-cols__side-text a {
  color: var(--signal);
  text-decoration: none;
  border-bottom: 1px solid rgba(79, 209, 224, 0.45);
}

.page-about .about-cols__side-text a:hover {
  border-bottom-color: var(--amber);
  color: var(--amber);
}

/* ---------- 时间轴 ---------- */
.page-about .about-tl-media {
  margin: 0 0 30px;
}

.page-about .about-tl-media img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  border: 1px solid var(--about-line);
}

.page-about .about-tl-media .media__caption {
  margin-top: 10px;
  font-size: var(--step-12);
  color: var(--cool-mid);
}

.page-about .about-timeline {
  position: relative;
  margin: 0;
  padding: 4px 0 0 34px;
  list-style: none;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 11px;
  top: 8px;
  bottom: 12px;
  width: 1px;
  background: linear-gradient(180deg, var(--signal), var(--ridge) 55%, rgba(21, 106, 138, 0.1));
}

.page-about .tl-item {
  position: relative;
  padding: 0 0 26px;
}

.page-about .tl-item::before {
  content: "";
  position: absolute;
  left: -34px;
  margin-left: 7px;
  top: 6px;
  width: 9px;
  height: 9px;
  border: 1px solid var(--signal);
  border-radius: 50%;
  background: var(--night);
  transition: background-color 0.24s ease-out, border-color 0.24s ease-out, box-shadow 0.24s ease-out;
}

.page-about .tl-item[data-visible]::before {
  background: var(--amber);
  border-color: var(--amber);
  box-shadow: 0 0 0 4px rgba(255, 106, 43, 0.14);
}

.page-about .tl-item__head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 6px 12px;
  margin: 0 0 7px;
}

.page-about .tl-item__idx {
  font-family: var(--font-mono);
  font-size: var(--step-14);
  color: var(--ridge);
}

.page-about .tl-item__era {
  font-family: var(--font-narrow);
  font-size: var(--step-16);
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--cool);
}

.page-about .tl-item .tag {
  font-size: 11px;
}

.page-about .tl-item__text {
  margin: 0;
  max-width: 44em;
  font-size: var(--step-14);
  line-height: 1.78;
  color: var(--cool-mid);
}

/* ---------- 编辑原则 ---------- */
.page-about .about-rule-media {
  margin: 0 0 28px;
}

.page-about .about-rule-media img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  border: 1px solid var(--about-line);
}

.page-about .about-rule-media .media__caption {
  margin-top: 10px;
  font-size: var(--step-12);
  color: var(--cool-mid);
}

.page-about .prin-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 18px;
}

.page-about .prin-card {
  position: relative;
  padding: 20px 18px 22px;
  background: rgba(14, 58, 79, 0.42);
  border-top: 2px solid rgba(79, 209, 224, 0.5);
}

.page-about .prin-card__no {
  margin: 0;
  font-family: var(--font-mono);
  font-size: var(--step-12);
  letter-spacing: 0.1em;
  color: var(--amber);
}

.page-about .prin-card__title {
  margin: 10px 0 0;
  font-family: var(--font-narrow);
  font-size: var(--step-20);
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--cool);
}

.page-about .prin-card__body {
  margin: 10px 0 0;
  font-size: var(--step-14);
  line-height: 1.78;
  color: var(--cool-mid);
}

.page-about .prin-card__how {
  margin: 14px 0 0;
  padding-left: 12px;
  border-left: 1px solid rgba(185, 242, 39, 0.45);
  font-size: var(--step-12);
  line-height: 1.7;
  color: var(--lime);
}

.page-about .prin-card__how a {
  color: var(--lime);
  text-decoration: none;
  border-bottom: 1px solid rgba(185, 242, 39, 0.5);
}

.page-about .prin-card__how a:hover {
  color: var(--amber);
  border-bottom-color: var(--amber);
}

/* ---------- 团队编制 ---------- */
.page-about .about-team-media {
  margin: 0 0 26px;
}

.page-about .about-team-media img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  border: 1px solid var(--about-line);
}

.page-about .about-team-media .media__caption {
  margin-top: 10px;
  font-size: var(--step-12);
  color: var(--cool-mid);
}

.page-about .about-team-table__caption {
  padding: 0 0 12px;
  text-align: left;
  font-family: var(--font-narrow);
  font-size: var(--step-12);
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--cool-mid);
}

.page-about .about-team-table tbody tr {
  transition: background-color 0.2s ease-out;
}

.page-about .about-team-table tbody tr:hover {
  background: rgba(79, 209, 224, 0.08);
}

.page-about .about-team-table__task {
  color: var(--cool-mid);
  transition: color 0.2s ease-out;
}

.page-about .about-team-table tbody tr:hover .about-team-table__task {
  color: var(--cool);
}

.page-about .about-team-note {
  margin: 18px 0 0;
  max-width: 44em;
  font-size: var(--step-14);
  line-height: 1.78;
  color: var(--cool-mid);
}

/* ---------- 合作生态与荣誉（纸面区） ---------- */
.page-about .eco-paper {
  background: var(--paper);
  color: var(--deep);
  border-radius: var(--radius-organic);
  padding: 24px 20px 26px;
}

.page-about .eco-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 20px;
}

.page-about .eco-cell {
  padding-bottom: 18px;
  border-bottom: 1px solid rgba(14, 58, 79, 0.22);
}

.page-about .eco-cell:last-child {
  border-bottom: none;
  padding-bottom: 0;
}

.page-about .eco-cell__num {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 40px;
  line-height: 1;
  color: var(--amber);
}

.page-about .eco-cell__name {
  margin: 10px 0 0;
  font-family: var(--font-narrow);
  font-size: var(--step-16);
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--deep);
}

.page-about .eco-cell__text {
  margin: 8px 0 0;
  font-size: var(--step-14);
  line-height: 1.75;
  color: #2C5568;
}

.page-about .eco-honor {
  margin: 24px 0 0;
  padding-top: 20px;
  border-top: 2px solid var(--deep);
}

.page-about .eco-honor__label {
  margin: 0;
  font-family: var(--font-narrow);
  font-size: var(--step-12);
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: #2C5568;
}

.page-about .eco-honor__list {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 12px;
  margin: 14px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .eco-honor__list li {
  padding: 7px 13px;
  font-family: var(--font-narrow);
  font-size: var(--step-14);
  letter-spacing: 0.04em;
  color: var(--deep);
  border: 1px solid rgba(14, 58, 79, 0.35);
  border-left: 3px solid var(--amber);
  border-radius: var(--radius);
  background: rgba(14, 58, 79, 0.05);
}

.page-about .eco-honor__note {
  margin: 16px 0 0;
  font-size: var(--step-12);
  line-height: 1.7;
  color: #2C5568;
}

/* ---------- 栏目关系 ---------- */
.page-about .map-list {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  margin: 0;
  padding: 0;
  list-style: none;
  background: var(--about-line-soft);
  border: 1px solid var(--about-line-soft);
}

.page-about .map-list__item {
  background: var(--night);
}

.page-about .map-list__link {
  display: flex;
  flex-direction: column;
  gap: 7px;
  padding: 18px 18px 20px;
  text-decoration: none;
  transition: background-color 0.2s ease-out, box-shadow 0.2s ease-out;
  box-shadow: inset 2px 0 0 transparent;
}

.page-about .map-list__link:hover {
  background: rgba(14, 58, 79, 0.6);
  box-shadow: inset 2px 0 0 var(--amber);
}

.page-about .map-list__name {
  font-family: var(--font-narrow);
  font-size: var(--step-20);
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--signal);
}

.page-about .map-list__link:hover .map-list__name {
  color: var(--amber);
}

.page-about .map-list__desc {
  font-size: var(--step-14);
  line-height: 1.7;
  color: var(--cool-mid);
}

.page-about .about-close {
  margin: 24px 0 0;
  max-width: 46em;
  padding-top: 18px;
  border-top: 1px solid var(--about-line-soft);
  font-size: var(--step-14);
  line-height: 1.78;
  color: var(--cool-mid);
}

/* ---------- 平板 ---------- */
@media (min-width: 700px) {
  .page-about .about-pad,
  .page-about .about-shell {
    --about-pad: 32px;
  }

  .page-about .about-cover {
    padding: 48px 0 56px;
  }

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

  .page-about .about-cols {
    grid-template-columns: minmax(0, 1.6fr) minmax(0, 1fr);
    gap: 32px;
    align-items: start;
  }

  .page-about .eco-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 26px;
  }

  .page-about .eco-cell {
    border-bottom: none;
    border-left: 1px solid rgba(14, 58, 79, 0.22);
    padding: 0 0 0 18px;
  }

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

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

  .page-about .prin-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 22px 26px;
    align-items: start;
  }

  .page-about .prin-card:nth-child(even) {
    margin-top: 34px;
  }

  .page-about .prin-grid {
    padding-bottom: 34px;
  }
}

/* ---------- 桌面 ---------- */
@media (min-width: 1024px) {
  .page-about .about-shell {
    display: grid;
    grid-template-columns: 182px minmax(0, 1fr);
    gap: 44px;
    padding-bottom: 96px;
  }

  .page-about .about-index {
    position: sticky;
    top: calc(var(--header-h) + 24px);
    align-self: start;
    padding-top: 40px;
  }

  .page-about .about-index__list {
    display: block;
    overflow: visible;
    padding-bottom: 0;
  }

  .page-about .about-index__list li + li {
    margin-top: 2px;
  }

  .page-about .about-index__link {
    width: 100%;
    padding: 9px 0 9px 14px;
    background: none;
    border: none;
    border-left: 2px solid var(--about-line);
    border-radius: 0;
  }

  .page-about .about-index__link[aria-current="true"] {
    background: none;
    border-left-color: var(--amber);
  }

  .page-about .about-index__link:hover {
    border-left-color: var(--signal);
  }

  .page-about .about-sec {
    padding: 62px 0 14px;
  }

  .page-about .about-sec:first-child {
    padding-top: 40px;
  }

  .page-about .about-cover {
    padding: 62px 0 74px;
  }

  .page-about .about-timeline {
    padding-left: 40px;
  }

  .page-about .tl-item::before {
    left: -40px;
    margin-left: 7px;
  }

  .page-about .about-timeline::before {
    left: 11px;
  }

  .page-about .about-facts__value {
    font-size: 34px;
  }

  .page-about .about-rule-media {
    float: right;
    width: 42%;
    margin: 4px 0 22px 32px;
  }

  .page-about .about-team-media {
    width: 62%;
    margin-bottom: 30px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-index__link,
  .page-about .tl-item::before,
  .page-about .about-team-table tbody tr,
  .page-about .about-team-table__task,
  .page-about .map-list__link {
    transition: none;
  }
}