.page-about {
  padding-bottom: clamp(48px, 8vw, 96px);
}

.page-about .crumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin: 22px 0 26px;
  font-size: 13px;
  letter-spacing: 0.04em;
  color: var(--stone);
}

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

.page-about .crumbs a:hover,
.page-about .crumbs a:focus-visible {
  color: var(--bone);
  border-bottom-color: var(--accent);
}

.page-about .crumbs [aria-current="page"] {
  color: var(--accent);
}

/* ---------- 首屏 ---------- */

.page-about .about-masthead {
  position: relative;
  padding: clamp(22px, 4vw, 44px);
  padding-right: clamp(52px, 9vw, 108px);
  border: 2px solid var(--line-strong);
  background: linear-gradient(158deg, var(--ink-800) 0%, var(--ink-900) 68%);
  box-shadow: var(--shadow-hard);
  overflow: hidden;
}

.page-about .about-masthead::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: min(220px, 42%);
  height: 4px;
  background: var(--accent);
}

.page-about .about-masthead__note {
  position: absolute;
  top: clamp(20px, 3vw, 40px);
  right: clamp(14px, 3vw, 32px);
  writing-mode: vertical-rl;
  letter-spacing: 0.26em;
  font-size: 12px;
  color: var(--stone);
}

.page-about .about-masthead__kicker {
  margin: 0 0 14px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.18em;
  color: var(--accent);
}

.page-about .about-masthead h1 {
  margin: 0 0 18px;
  font-size: clamp(1.7rem, 5.2vw, 3.2rem);
  line-height: 1.2;
  letter-spacing: -0.015em;
  color: var(--bone);
  max-width: 22ch;
}

.page-about .about-masthead__lede {
  margin: 0;
  max-width: 60ch;
  font-size: clamp(0.95rem, 1.4vw, 1.05rem);
  line-height: 1.85;
  color: rgba(239, 234, 223, 0.84);
}

.page-about .about-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin-top: 30px;
  background: var(--line);
  border: 2px solid var(--line-strong);
}

.page-about .about-stat {
  background: var(--ink-900);
  padding: 14px 16px;
}

.page-about .about-stat__num {
  display: block;
  font-family: var(--font-mono);
  font-weight: 600;
  font-size: clamp(1.35rem, 4.4vw, 2.1rem);
  line-height: 1.1;
  color: var(--accent);
  letter-spacing: -0.01em;
}

.page-about .about-stat__label {
  display: block;
  margin-top: 6px;
  font-size: 12.5px;
  line-height: 1.5;
  color: var(--stone);
}

/* ---------- 布局 ---------- */

.page-about .about-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 26px;
  margin-top: clamp(30px, 5vw, 52px);
}

/* ---------- 目录 ---------- */

.page-about .about-toc {
  border-left: 2px solid var(--line-strong);
  padding-left: 16px;
}

.page-about .about-toc__title {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.2em;
  color: var(--stone);
}

.page-about .about-toc__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.page-about .about-toc__list a {
  display: block;
  padding: 6px 10px;
  border: 1px solid var(--line);
  font-size: 13px;
  line-height: 1.4;
  color: var(--stone);
  text-decoration: none;
  transition: color 0.2s ease, border-color 0.2s ease, background 0.2s ease;
}

.page-about .about-toc__list a:hover,
.page-about .about-toc__list a:focus-visible {
  color: var(--accent);
  border-color: var(--accent);
  background: var(--accent-soft);
}

/* ---------- 正文面板 ---------- */

.page-about .about-body {
  display: grid;
  gap: clamp(24px, 3.6vw, 44px);
  counter-reset: about-sec;
}

.page-about .about-panel {
  counter-increment: about-sec;
  position: relative;
  padding: clamp(20px, 3.4vw, 34px);
  border: 2px solid var(--line-strong);
  background: var(--ink-800);
}

.page-about .about-panel::before {
  content: "0" counter(about-sec);
  display: block;
  margin-bottom: 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.2em;
  color: var(--stone);
}

.page-about .about-panel h2 {
  margin: 0 0 16px;
  font-size: clamp(1.25rem, 3.2vw, 1.9rem);
  line-height: 1.28;
  letter-spacing: -0.012em;
  color: var(--bone);
  max-width: 26ch;
}

.page-about .about-panel p {
  margin: 0 0 14px;
  max-width: 68ch;
  font-size: clamp(0.94rem, 1.3vw, 1rem);
  line-height: 1.85;
  color: rgba(239, 234, 223, 0.82);
}

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

.page-about .about-panel a {
  color: var(--lake);
  text-decoration: none;
  border-bottom: 1px solid rgba(77, 208, 225, 0.45);
}

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

.page-about .about-note {
  margin-top: 18px !important;
  padding-top: 14px;
  border-top: 1px dashed var(--line);
  font-size: 13.5px !important;
  color: var(--stone) !important;
}

.page-about .round-divider {
  margin: 24px 0 20px;
}

/* ---------- 标签墙 ---------- */

.page-about .about-tags {
  list-style: none;
  margin: 20px 0 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.page-about .about-tags li {
  padding: 5px 11px;
  border: 1px solid var(--line-strong);
  background: var(--ink-900);
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: 0.02em;
  color: var(--bone);
}

.page-about .about-tags li.is-key {
  border-color: var(--accent);
  color: var(--accent);
  background: var(--accent-soft);
}

/* ---------- 图片 ---------- */

.page-about .about-figure {
  margin: 24px 0 0;
  border: 2px solid var(--line-strong);
  background: var(--ink-900);
}

.page-about .about-figure__img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 4 / 3;
  object-fit: cover;
}

.page-about .about-figure__img--venue {
  aspect-ratio: 10 / 7;
}

.page-about .about-figure__img--desk {
  aspect-ratio: 3 / 2;
}

.page-about .about-figure__cap {
  padding: 10px 14px;
  border-top: 1px solid var(--line);
  font-size: 13px;
  line-height: 1.65;
  color: var(--stone);
}

/* ---------- 信息表 ---------- */

.page-about .about-table-wrap {
  margin: 22px 0 0;
  overflow-x: auto;
  border: 2px solid var(--line-strong);
}

.page-about .about-table {
  width: 100%;
  min-width: 420px;
  border-collapse: collapse;
}

.page-about .about-table caption {
  padding: 12px 14px;
  text-align: left;
  font-size: 12.5px;
  letter-spacing: 0.08em;
  color: var(--stone);
  border-bottom: 1px solid var(--line);
}

.page-about .about-table th,
.page-about .about-table td {
  padding: 12px 14px;
  text-align: left;
  vertical-align: top;
  border: 1px solid var(--line);
  font-size: 14px;
  line-height: 1.7;
}

.page-about .about-table thead th {
  background: var(--ink-700);
  color: var(--bone);
  font-size: 13px;
  letter-spacing: 0.08em;
}

.page-about .about-table tbody tr:nth-child(odd) {
  background: rgba(239, 234, 223, 0.035);
}

.page-about .about-table tbody td {
  color: rgba(239, 234, 223, 0.82);
}

.page-about .about-table tbody td:first-child {
  font-family: var(--font-mono);
  font-size: 13.5px;
  color: var(--accent);
  white-space: nowrap;
}

/* ---------- 团队分工 ---------- */

.page-about .about-team {
  list-style: none;
  margin: 22px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--line);
  border: 2px solid var(--line-strong);
}

.page-about .about-team li {
  background: var(--ink-900);
  padding: 14px 16px;
}

.page-about .about-team__num {
  display: block;
  font-family: var(--font-mono);
  font-weight: 600;
  font-size: clamp(1.4rem, 3.6vw, 1.8rem);
  line-height: 1.1;
  color: var(--accent);
}

.page-about .about-team__label {
  display: block;
  margin-top: 5px;
  font-size: 12.5px;
  line-height: 1.55;
  color: var(--stone);
}

/* ---------- 时间线 ---------- */

.page-about .about-timeline {
  list-style: none;
  margin: 24px 0 0;
  padding: 0;
  display: grid;
  gap: 12px;
}

.page-about .about-timeline__item {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 6px;
  padding: 14px 16px;
  border: 1px solid var(--line);
  border-left: 3px solid var(--accent);
  background: var(--ink-900);
  transition: border-color 0.25s ease, background 0.25s ease;
}

.page-about .about-timeline__item:hover,
.page-about .about-timeline__item:focus-within {
  border-left-color: var(--signal);
  background: var(--ink-700);
}

.page-about .about-timeline__year {
  font-family: var(--font-mono);
  font-weight: 600;
  font-size: 1.15rem;
  letter-spacing: 0.06em;
  color: var(--accent);
}

.page-about .about-timeline__text h3 {
  margin: 0 0 6px;
  font-size: 1rem;
  line-height: 1.4;
  color: var(--bone);
}

.page-about .about-timeline__text p {
  margin: 0;
  font-size: 13.5px;
  line-height: 1.75;
  color: rgba(239, 234, 223, 0.76);
  max-width: 62ch;
}

/* ---------- 用户场景 ---------- */

.page-about .about-users {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
  margin-top: 22px;
}

.page-about .about-user {
  padding: 18px;
  border: 2px solid var(--line);
  background: var(--ink-900);
  border-top-width: 4px;
}

.page-about .about-user--fan {
  border-top-color: var(--moss);
}

.page-about .about-user--creator {
  border-top-color: var(--acid);
}

.page-about .about-user--analyst {
  border-top-color: var(--signal);
}

.page-about .about-user h3 {
  margin: 0 0 8px;
  font-size: 1rem;
  line-height: 1.4;
  color: var(--bone);
}

.page-about .about-user p {
  margin: 0;
  font-size: 13.5px;
  line-height: 1.75;
  color: rgba(239, 234, 223, 0.76);
}

/* ---------- 底部入口 ---------- */

.page-about .about-cta {
  padding: clamp(20px, 3.4vw, 32px);
  border: 2px solid var(--accent);
  background: var(--accent-soft);
}

.page-about .about-cta__title {
  margin: 0 0 16px;
  font-size: clamp(1.05rem, 2.4vw, 1.35rem);
  font-weight: 700;
  line-height: 1.4;
  color: var(--bone);
}

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

/* ---------- 响应式 ---------- */

@media (min-width: 720px) {
  .page-about .about-masthead h1 {
    max-width: 24ch;
  }

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

  .page-about .about-stat {
    padding: 18px 20px;
  }

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

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

  .page-about .about-timeline__item {
    grid-template-columns: 96px minmax(0, 1fr);
    gap: 18px;
    align-items: start;
    padding: 16px 20px;
  }
}

@media (min-width: 1000px) {
  .page-about .about-layout {
    grid-template-columns: 208px minmax(0, 1fr);
    gap: clamp(32px, 4vw, 56px);
    align-items: start;
  }

  .page-about .about-toc {
    position: sticky;
    top: calc(var(--topbar-h) + 28px);
    max-height: calc(100vh - var(--topbar-h) - 56px);
    overflow-y: auto;
  }

  .page-about .about-toc__list {
    display: block;
  }

  .page-about .about-toc__list li + li {
    border-top: 1px dashed var(--line);
  }

  .page-about .about-toc__list a {
    padding: 9px 0;
    border: 0;
    background: transparent;
  }

  .page-about .about-toc__list a:hover,
  .page-about .about-toc__list a:focus-visible {
    background: transparent;
    color: var(--accent);
  }

  .page-about .about-panel {
    padding: clamp(28px, 3vw, 40px);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-timeline__item,
  .page-about .about-toc__list a,
  .page-about .crumbs a {
    transition: none;
  }
}