.page-about {
  --about-paper-ink: #0B1714;
  --about-paper-muted: #5D6159;
  --about-paper-line: #DCD3C2;
}

/* ---------- 首屏 ---------- */

.page-about .about-hero {
  padding: 24px 0 40px;
  border-bottom: 1px solid var(--ink-line);
}

.page-about .about-hero__grid {
  display: grid;
  gap: 30px;
  margin-top: 26px;
}

.page-about .about-hero__title {
  margin: 12px 0 0;
  font-size: clamp(30px, 7vw, 54px);
  line-height: 1.06;
  letter-spacing: -0.01em;
  font-weight: 900;
  color: var(--white-000);
}

.page-about .about-hero__lead {
  margin: 18px 0 0;
  max-width: 34em;
  font-size: 16px;
  line-height: 1.75;
  color: var(--text-body);
}

.page-about .about-hero__actions {
  margin-top: 26px;
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.page-about .about-hero__board {
  padding: 22px;
  border-radius: var(--radius-panel);
}

.page-about .about-steps {
  list-style: none;
  margin: 14px 0 0;
  padding: 0;
  display: grid;
  gap: 10px;
}

.page-about .about-steps__row {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  align-items: center;
  gap: 12px;
  padding: 12px 14px;
  border: 1px solid var(--ink-line);
  border-radius: var(--radius-sm);
  background: var(--ink-950);
  transition: background var(--ease), border-color var(--ease);
}

.page-about .about-steps__row:hover {
  background: var(--ink-800);
  border-color: var(--cyan-400);
}

.page-about .about-steps__ver {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  padding: 4px 10px;
  border-radius: var(--radius-pill);
  border: 1px solid var(--ink-line);
  background: var(--ink-800);
  color: var(--cyan-400);
  white-space: nowrap;
}

.page-about .about-steps__name {
  font-size: 14px;
  line-height: 1.6;
  color: var(--text-body);
}

.page-about .about-hero__note {
  margin: 16px 0 0;
  font-size: 13px;
  line-height: 1.6;
  color: var(--slate-400);
}

/* ---------- 主体骨架 ---------- */

.page-about .about-shell {
  display: grid;
  gap: 36px;
  padding: 40px 0 72px;
}

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

.page-about .about-index__list {
  list-style: none;
  margin: 12px 0 0;
  padding: 0;
  display: grid;
  gap: 2px;
}

.page-about .about-index__link {
  display: block;
  padding: 9px 12px;
  font-size: 13px;
  line-height: 1.5;
  color: var(--slate-400);
  text-decoration: none;
  border-left: 2px solid var(--ink-line);
  transition: color var(--ease), border-color var(--ease), background var(--ease);
}

.page-about .about-index__link:hover,
.page-about .about-index__link:focus-visible {
  color: var(--cyan-400);
  border-left-color: var(--cyan-400);
  background: var(--ink-800);
}

.page-about .about-main {
  min-width: 0;
}

/* ---------- 章节 ---------- */

.page-about .about-section {
  padding-top: 52px;
  margin-top: 52px;
  border-top: 1px solid var(--ink-line);
  scroll-margin-top: calc(var(--topbar-h) + 24px);
}

.page-about .about-section--first {
  padding-top: 0;
  margin-top: 0;
  border-top: 0;
}

.page-about .about-section__title {
  margin: 10px 0 0;
  font-size: clamp(22px, 4.4vw, 30px);
  line-height: 1.18;
  letter-spacing: -0.01em;
  font-weight: 800;
  color: var(--white-000);
}

.page-about .about-section__lead {
  margin: 14px 0 0;
  max-width: 42em;
  font-size: 16px;
  line-height: 1.75;
  color: var(--text-body);
}

.page-about .about-p {
  margin: 18px 0 0;
  max-width: 68ch;
  font-size: 16px;
  line-height: 1.75;
  color: var(--text-body);
}

/* ---------- 日常三件事 ---------- */

.page-about .about-daily {
  margin-top: 24px;
  display: grid;
  gap: 14px;
}

.page-about .about-daily__item {
  padding: 20px;
  border: 1px solid var(--ink-line);
  border-radius: var(--radius-sm);
  background: var(--ink-800);
  transition: border-color var(--ease), background var(--ease);
}

.page-about .about-daily__item:hover {
  border-color: var(--cyan-400);
}

.page-about .about-daily__idx {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--amber-400);
}

.page-about .about-daily__title {
  margin: 10px 0 0;
  font-size: 17px;
  line-height: 1.4;
  color: var(--white-000);
}

.page-about .about-daily__text {
  margin: 8px 0 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--slate-400);
}

/* ---------- 图片 ---------- */

.page-about .about-figure {
  margin: 24px 0 0;
}

.page-about .about-figure .media {
  border-radius: var(--radius-panel);
  overflow: hidden;
}

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

.page-about .about-figure__cap {
  margin: 10px 0 0;
  font-size: 13px;
  line-height: 1.6;
  color: var(--slate-400);
}

/* ---------- 层级时间线 ---------- */

.page-about .about-flow {
  list-style: none;
  margin: 28px 0 0;
  padding: 0 0 0 22px;
  position: relative;
}

.page-about .about-flow::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 8px;
  bottom: 8px;
  width: 1px;
  background: var(--ink-line);
}

.page-about .about-flow__item {
  position: relative;
  padding: 0 0 26px 10px;
}

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

.page-about .about-flow__node {
  position: absolute;
  left: -22px;
  top: 5px;
  width: 11px;
  height: 11px;
  border-radius: 50%;
  background: var(--amber-400);
  box-shadow: 0 0 0 4px rgba(255, 180, 84, 0.14);
}

.page-about .about-flow__title {
  margin: 0;
  font-size: 17px;
  line-height: 1.45;
  color: var(--white-000);
}

.page-about .about-flow__text {
  margin: 8px 0 0;
  font-size: 15px;
  line-height: 1.75;
  color: var(--text-body);
  max-width: 62ch;
}

.page-about .about-flow__metric {
  margin: 10px 0 0;
  font-family: var(--font-mono);
  font-size: 14px;
  letter-spacing: 0.04em;
  color: var(--cyan-400);
}

/* ---------- 暖纸编年面板 ---------- */

.page-about .about-chrono {
  padding: 24px;
  border: 1px solid var(--about-paper-line);
  border-radius: var(--radius-panel);
  background: var(--paper-100);
}

.page-about .about-chrono .meta-label {
  color: var(--about-paper-muted);
}

.page-about .about-chrono .about-section__title {
  color: var(--about-paper-ink);
}

.page-about .about-chrono__lead {
  margin: 14px 0 0;
  max-width: 42em;
  font-size: 16px;
  line-height: 1.75;
  color: var(--about-paper-muted);
}

.page-about .about-chrono .about-figure .media {
  border-radius: var(--radius-sm);
}

.page-about .about-chrono__list {
  list-style: none;
  margin: 22px 0 0;
  padding: 0;
  display: grid;
  gap: 10px;
}

.page-about .about-chrono__item {
  border: 1px solid var(--about-paper-line);
  border-radius: var(--radius-sm);
  background: rgba(255, 255, 255, 0.55);
  overflow: hidden;
}

.page-about .about-chrono__sum {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 14px 16px;
  cursor: pointer;
  list-style: none;
  font-weight: 700;
  color: var(--about-paper-ink);
}

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

.page-about .about-chrono__sum::after {
  content: "＋";
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 14px;
  color: var(--about-paper-muted);
}

.page-about .about-chrono__item[open] .about-chrono__sum::after {
  content: "－";
}

.page-about .about-chrono__ver {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  padding: 3px 9px;
  border-radius: var(--radius-pill);
  background: var(--ink-950);
  color: var(--cyan-400);
  white-space: nowrap;
}

.page-about .about-chrono__name {
  font-size: 15px;
  line-height: 1.45;
}

.page-about .about-chrono__body {
  margin: 0;
  padding: 0 16px 16px;
  font-size: 14px;
  line-height: 1.75;
  color: var(--about-paper-muted);
}

/* ---------- 轮值表 ---------- */

.page-about .about-shift {
  list-style: none;
  margin: 22px 0 0;
  padding: 0;
  border: 1px solid var(--ink-line);
  border-radius: var(--radius-sm);
  overflow: hidden;
}

.page-about .about-shift__row {
  display: grid;
  gap: 4px;
  padding: 14px 16px;
  border-top: 1px solid var(--ink-line);
  transition: background var(--ease), box-shadow var(--ease);
}

.page-about .about-shift__row:first-child {
  border-top: 0;
}

.page-about .about-shift__row:hover {
  background: var(--ink-800);
  box-shadow: inset 3px 0 0 var(--cyan-400);
}

.page-about .about-shift__time {
  font-family: var(--font-mono);
  font-size: 14px;
  letter-spacing: 0.02em;
  color: var(--cyan-400);
}

.page-about .about-shift__label {
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--amber-400);
}

.page-about .about-shift__note {
  font-size: 14px;
  line-height: 1.7;
  color: var(--slate-400);
}

/* ---------- 规模数字 ---------- */

.page-about .about-stats {
  margin-top: 24px;
  display: grid;
  gap: 1px;
  background: var(--ink-line);
  border: 1px solid var(--ink-line);
  border-radius: var(--radius-panel);
  overflow: hidden;
}

.page-about .about-stat {
  padding: 22px 20px;
  background: var(--ink-950);
}

.page-about .about-stat__num {
  margin: 0;
  font-family: var(--font-mono);
  font-size: clamp(28px, 6vw, 38px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--white-000);
}

.page-about .about-stat__num em {
  font-style: normal;
  margin-left: 4px;
  font-size: 0.48em;
  color: var(--cyan-400);
}

.page-about .about-stat__label {
  margin: 10px 0 0;
  font-size: 13px;
  line-height: 1.65;
  color: var(--slate-400);
}

/* ---------- 合作 ---------- */

.page-about .about-partners {
  margin-top: 24px;
  display: grid;
  gap: 14px;
}

.page-about .about-partner {
  padding: 20px;
  border: 1px solid var(--ink-line);
  border-left: 3px solid var(--amber-400);
  border-radius: var(--radius-sm);
  background: var(--ink-800);
  transition: border-color var(--ease), background var(--ease);
}

.page-about .about-partner:hover {
  background: var(--ink-700);
  border-color: var(--cyan-400);
  border-left-color: var(--cyan-400);
}

.page-about .about-partner__title {
  margin: 0;
  font-size: 16px;
  line-height: 1.4;
  color: var(--white-000);
}

.page-about .about-partner__text {
  margin: 9px 0 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--slate-400);
}

.page-about .about-actions {
  margin-top: 22px;
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

/* ---------- 收藏夹 ---------- */

.page-about .about-fav {
  padding: 24px;
  border-radius: var(--radius-panel);
}

.page-about .about-fav__text {
  margin: 14px 0 0;
  max-width: 56ch;
  font-size: 15px;
  line-height: 1.75;
  color: var(--text-body);
}

/* ---------- 响应式 ---------- */

@media (min-width: 700px) {
  .page-about .about-daily {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .about-shift__row {
    grid-template-columns: 168px 96px minmax(0, 1fr);
    align-items: center;
    gap: 16px;
  }

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

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

  .page-about .about-chrono {
    padding: 32px;
  }

  .page-about .about-fav {
    padding: 32px;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero {
    padding: 32px 0 52px;
  }

  .page-about .about-hero__grid {
    grid-template-columns: 1.08fr 0.92fr;
    gap: 48px;
    align-items: center;
    margin-top: 34px;
  }
}

@media (min-width: 1024px) {
  .page-about .about-shell {
    grid-template-columns: 200px minmax(0, 1fr);
    gap: 44px;
    padding: 52px 0 88px;
  }

  .page-about .about-index {
    display: block;
    position: sticky;
    top: calc(var(--topbar-h) + 28px);
    align-self: start;
  }

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

  .page-about .about-section {
    padding-top: 64px;
    margin-top: 64px;
  }

  .page-about .about-section--first {
    padding-top: 0;
    margin-top: 0;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about * {
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
  }
}