.page-about {
  background-color: var(--ink);
  color: var(--paper);
  font-family: var(--font-body);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  isolation: isolate;
  overflow: hidden;
  padding: clamp(104px, 16vw, 156px) 0 clamp(44px, 7vw, 72px);
  border-bottom: 2px solid var(--line);
  background:
    repeating-linear-gradient(90deg, rgba(245, 241, 232, 0.035) 0 1px, transparent 1px 88px),
    linear-gradient(158deg, #1c1714 0%, var(--ink) 54%, #0d0c0b 100%);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  z-index: -1;
  top: -180px;
  right: -200px;
  width: clamp(320px, 56vw, 660px);
  height: clamp(320px, 56vw, 660px);
  background: linear-gradient(135deg, var(--flame) 0%, #a8320b 100%);
  opacity: 0.2;
  clip-path: polygon(0 0, 100% 0, 100% 70%, 26% 100%);
  transform: rotate(14deg);
  pointer-events: none;
}

.page-about .about-hero .breadcrumbs {
  margin-bottom: 26px;
}

.page-about .about-kicker {
  display: inline-block;
  margin: 0 0 18px;
  padding: 6px 12px;
  font-size: 11.5px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--flame);
  background: rgba(255, 90, 31, 0.1);
  border-left: 3px solid var(--flame);
}

.page-about .about-hero h1 {
  margin: 0;
  max-width: 16em;
  font-family: var(--font-display);
  font-size: clamp(32px, 6.2vw, 68px);
  font-weight: 900;
  line-height: 1.08;
  letter-spacing: -0.015em;
  color: var(--paper);
}

.page-about .about-hero h1 .hl {
  color: var(--flame);
  background: linear-gradient(transparent 62%, rgba(255, 90, 31, 0.22) 62%);
}

.page-about .about-lead {
  max-width: 36em;
  margin: 24px 0 0;
  font-size: clamp(15px, 2.3vw, 17.5px);
  line-height: 1.85;
  color: var(--mist);
}

.page-about .about-stat-strip {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 40px 0 0;
  padding: 0;
  list-style: none;
  background: var(--line);
  border: 2px solid var(--line);
}

.page-about .about-stat-strip li {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 18px 16px;
  background: var(--ink-panel);
}

.page-about .stat-num {
  font-family: var(--font-mono);
  font-size: clamp(26px, 4.4vw, 38px);
  font-weight: 700;
  line-height: 1;
  color: var(--flame);
}

.page-about .about-stat-strip li:nth-child(even) .stat-num {
  color: var(--cyan);
}

.page-about .stat-label {
  font-size: 12.5px;
  line-height: 1.55;
  color: var(--mist);
}

@media (min-width: 720px) {
  .page-about .about-stat-strip {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

/* ---------- 年份索引 + 章节 ---------- */
.page-about .about-story-section {
  padding-block: clamp(52px, 8vw, 96px);
}

.page-about .about-story {
  display: grid;
  gap: 36px;
}

.page-about .about-rail {
  padding-top: 18px;
  border-top: 2px solid var(--flame);
}

.page-about .rail-title {
  margin: 0 0 14px;
  font-size: 11px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--mist);
}

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

.page-about .rail-item {
  display: grid;
  grid-template-columns: 1fr auto;
  align-items: center;
  gap: 6px 10px;
  padding: 12px 14px;
  background: var(--ink-panel);
  border-left: 3px solid var(--line);
  transition: border-color 0.2s ease, background-color 0.2s ease;
}

.page-about .rail-item:hover,
.page-about .rail-item:focus-within {
  background: #24201d;
  border-left-color: var(--flame);
}

.page-about .rail-year {
  font-size: 19px;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--paper);
  transition: color 0.2s ease;
}

.page-about .rail-item:hover .rail-year,
.page-about .rail-item:focus-within .rail-year {
  color: var(--flame);
}

.page-about .rail-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--flame);
}

.page-about .rail-item[data-year="2023"] .rail-dot {
  background: var(--cyan);
}

.page-about .rail-event {
  grid-column: 1 / -1;
  max-height: 0;
  overflow: hidden;
  opacity: 0;
  font-size: 12px;
  line-height: 1.55;
  color: var(--mist);
  transition: max-height 0.24s ease, opacity 0.24s ease, margin-top 0.24s ease;
}

.page-about .rail-item:hover .rail-event,
.page-about .rail-item:focus-within .rail-event {
  max-height: 70px;
  margin-top: 4px;
  opacity: 1;
}

@media (hover: none) {
  .page-about .rail-event {
    max-height: none;
    margin-top: 4px;
    opacity: 1;
  }
}

.page-about .about-chapters {
  display: grid;
  gap: clamp(34px, 5.5vw, 60px);
}

.page-about .about-chapter {
  position: relative;
  padding-left: 18px;
  border-left: 2px solid var(--line);
}

.page-about .about-chapter:first-child {
  border-left-color: var(--flame);
}

.page-about .chapter-head {
  display: flex;
  align-items: baseline;
  gap: 12px;
  margin-bottom: 14px;
}

.page-about .chapter-index {
  flex: none;
  font-size: 12.5px;
  font-weight: 700;
  letter-spacing: 0.12em;
  color: var(--flame);
}

.page-about .chapter-title {
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(21px, 3.6vw, 32px);
  font-weight: 900;
  line-height: 1.22;
  letter-spacing: -0.01em;
  color: var(--paper);
}

.page-about .chapter-body {
  display: grid;
  gap: 22px;
}

.page-about .chapter-text p {
  margin: 0 0 14px;
  font-size: clamp(14.5px, 1.7vw, 16.5px);
  line-height: 1.85;
  color: #d8d2c8;
}

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

.page-about .inline-link {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(45, 226, 230, 0.45);
}

.page-about .inline-link:hover,
.page-about .inline-link:focus-visible {
  border-bottom-color: var(--cyan);
}

.page-about .chapter-media {
  margin: 0;
}

.page-about .chapter-media img,
.page-about .work-media img,
.page-about .partner-media img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
}

.page-about .chapter-media figcaption,
.page-about .work-media figcaption,
.page-about .partner-media figcaption {
  margin-top: 10px;
  padding-left: 10px;
  font-size: 12.5px;
  line-height: 1.6;
  color: var(--mist);
  border-left: 2px solid var(--flame);
}

@media (min-width: 780px) {
  .page-about .chapter-body {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    align-items: start;
    gap: 32px;
  }
}

@media (min-width: 980px) {
  .page-about .about-story {
    grid-template-columns: 208px minmax(0, 1fr);
    gap: 60px;
  }

  .page-about .about-rail {
    position: sticky;
    top: 112px;
    align-self: start;
  }
}

/* ---------- 日常工作 ---------- */
.page-about .about-work {
  padding-block: clamp(52px, 8vw, 96px);
  background: var(--ink-deep);
  border-top: 2px solid var(--line);
  border-bottom: 2px solid var(--line);
}

.page-about .about-eyebrow {
  margin: 0 0 12px;
  font-size: 11.5px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--flame);
}

.page-about .work-row {
  display: grid;
  gap: 32px;
}

.page-about .work-row + .work-row {
  margin-top: clamp(48px, 8vw, 88px);
  padding-top: clamp(40px, 6vw, 72px);
  border-top: 1px solid var(--line);
}

.page-about .work-text h2,
.page-about .about-section-head h2,
.page-about .about-next h2 {
  margin: 0 0 18px;
  font-family: var(--font-display);
  font-size: clamp(23px, 4vw, 40px);
  font-weight: 900;
  line-height: 1.16;
  letter-spacing: -0.012em;
  color: var(--paper);
}

.page-about .work-text p {
  margin: 0 0 16px;
  font-size: clamp(14.5px, 1.7vw, 16.5px);
  line-height: 1.85;
  color: #d8d2c8;
}

.page-about .work-list {
  display: grid;
  gap: 1px;
  margin: 22px 0;
  padding: 0;
  list-style: none;
  background: var(--line);
  border: 2px solid var(--line);
}

.page-about .work-list li {
  display: grid;
  gap: 4px;
  padding: 13px 15px;
  font-size: 13.5px;
  line-height: 1.7;
  color: var(--mist);
  background: var(--ink-panel);
}

.page-about .work-list-key {
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.08em;
  color: var(--flame);
}

.page-about .work-footnote {
  margin: 0;
  padding: 12px 14px;
  font-size: 13px;
  line-height: 1.7;
  color: var(--amber);
  background: rgba(255, 200, 87, 0.08);
  border-left: 3px solid var(--amber);
}

.page-about .work-note {
  align-self: start;
  padding: 22px 20px 24px;
  background: var(--ink-panel);
  border: 2px solid var(--line);
  box-shadow: var(--shadow-hard);
}

.page-about .note-title {
  margin: 0 0 14px;
  font-size: 11px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--mist);
}

.page-about .note-list {
  margin: 0 0 20px;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 12px;
}

.page-about .note-list li {
  display: grid;
  grid-template-columns: 76px minmax(0, 1fr);
  gap: 10px;
  align-items: baseline;
  font-size: 13.5px;
  line-height: 1.65;
  color: #d8d2c8;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--line);
}

.page-about .note-list li:last-child {
  padding-bottom: 0;
  border-bottom: none;
}

.page-about .note-list .mono {
  font-size: 12.5px;
  font-weight: 700;
  color: var(--cyan);
}

.page-about .work-media {
  margin: 0;
  width: 100%;
  max-width: 460px;
}

.page-about .work-meters {
  display: grid;
  gap: 14px;
  margin-top: 22px;
  padding: 18px 16px;
  background: var(--ink-panel);
  border: 2px solid var(--line);
}

.page-about .meter-row {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 8px 12px;
  align-items: center;
}

.page-about .meter-label {
  font-size: 12.5px;
  color: var(--mist);
}

.page-about .meter-num {
  font-size: 12.5px;
  font-weight: 700;
  color: var(--cyan);
}

.page-about .meter-row .meter {
  grid-column: 1 / -1;
}

@media (min-width: 880px) {
  .page-about .work-row {
    grid-template-columns: minmax(0, 1.12fr) minmax(0, 0.88fr);
    gap: 56px;
    align-items: start;
  }

  .page-about .work-row--flip {
    grid-template-columns: minmax(0, 0.88fr) minmax(0, 1.12fr);
  }

  .page-about .work-row--flip .work-text {
    order: 2;
  }

  .page-about .work-row--flip .work-media {
    order: 1;
  }

  .page-about .work-note {
    position: sticky;
    top: 112px;
  }
}

/* ---------- 覆盖范围 ---------- */
.page-about .about-coverage {
  padding-block: clamp(52px, 8vw, 96px);
}

.page-about .about-section-head {
  max-width: 46em;
}

.page-about .about-section-head--tight {
  margin-top: clamp(32px, 5vw, 56px);
}

.page-about .about-section-note {
  margin: 0;
  font-size: clamp(14px, 1.7vw, 16px);
  line-height: 1.85;
  color: var(--mist);
}

.page-about .coverage-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
  margin: 30px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .coverage-card {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 18px 16px 20px;
  background: var(--ink-panel);
  border: 2px solid var(--line);
  border-top: 3px solid var(--line);
  transition: border-color 0.2s ease, transform 0.2s ease;
}

.page-about .coverage-card:hover {
  border-top-color: var(--flame);
  transform: translateY(-3px);
}

.page-about .coverage-count {
  font-family: var(--font-mono);
  font-size: clamp(30px, 4.6vw, 44px);
  font-weight: 700;
  line-height: 1;
  color: var(--cyan);
}

.page-about .coverage-name {
  font-size: 15px;
  font-weight: 700;
  color: var(--paper);
}

.page-about .coverage-desc {
  font-size: 12.5px;
  line-height: 1.6;
  color: var(--mist);
}

@media (min-width: 760px) {
  .page-about .coverage-grid {
    grid-template-columns: repeat(5, minmax(0, 1fr));
  }
}

/* ---------- 团队 ---------- */
.page-about .about-team {
  padding-block: clamp(52px, 8vw, 96px);
  background:
    repeating-linear-gradient(0deg, rgba(245, 241, 232, 0.03) 0 1px, transparent 1px 32px),
    var(--ink-deep);
  border-top: 2px solid var(--line);
  border-bottom: 2px solid var(--line);
}

.page-about .team-grid {
  display: grid;
  gap: 16px;
  margin-top: 30px;
}

.page-about .team-card {
  background: var(--ink-panel);
  border: 2px solid var(--line);
  box-shadow: var(--shadow-soft);
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.page-about .team-card:hover {
  border-color: var(--flame-soft);
}

.page-about .team-card[open] {
  border-color: var(--flame);
  box-shadow: var(--shadow-hard);
}

.page-about .team-card summary {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px 10px;
  padding: 16px 18px;
  cursor: pointer;
  list-style: none;
}

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

.page-about .team-card summary::after {
  content: "+";
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 18px;
  line-height: 1;
  color: var(--flame);
}

.page-about .team-card[open] summary::after {
  content: "–";
}

.page-about .team-index {
  flex: none;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 26px;
  height: 26px;
  font-size: 12px;
  font-weight: 700;
  color: var(--ink);
  background: var(--flame);
  clip-path: polygon(0 0, 100% 0, 100% 72%, 72% 100%, 0 100%);
}

.page-about .team-name {
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 900;
  letter-spacing: 0.01em;
  color: var(--paper);
}

.page-about .team-tag {
  width: 100%;
  padding-left: 36px;
  font-size: 11.5px;
  letter-spacing: 0.1em;
  color: var(--cyan);
}

.page-about .team-body {
  padding: 2px 18px 20px;
  border-top: 1px solid var(--line);
}

.page-about .team-body p {
  margin: 14px 0 0;
  font-size: 13.5px;
  line-height: 1.8;
  color: var(--mist);
}

@media (min-width: 800px) {
  .page-about .team-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    align-items: start;
  }

  .page-about .team-card:nth-child(2) {
    margin-top: 26px;
  }

  .page-about .team-card:nth-child(3) {
    margin-top: 52px;
  }

  .page-about .team-tag {
    padding-left: 0;
  }
}

/* ---------- 合作生态 ---------- */
.page-about .about-partners {
  padding-block: clamp(52px, 8vw, 96px);
}

.page-about .partner-media {
  margin: 0 0 clamp(30px, 5vw, 48px);
}

.page-about .partner-strip {
  display: grid;
  gap: 1px;
  margin-top: 28px;
  background: var(--line);
  border: 2px solid var(--line);
}

.page-about .partner-cell {
  padding: 24px 20px 26px;
  background: var(--ink-panel);
}

.page-about .partner-num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(38px, 6vw, 56px);
  font-weight: 700;
  line-height: 1;
  color: var(--flame);
}

.page-about .partner-num--cyan {
  color: var(--cyan);
}

.page-about .partner-name {
  display: block;
  margin-top: 8px;
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 900;
  color: var(--paper);
}

.page-about .partner-cell p {
  margin: 12px 0 0;
  font-size: 13.5px;
  line-height: 1.8;
  color: var(--mist);
}

@media (min-width: 760px) {
  .page-about .partner-strip {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

/* ---------- 下一步 ---------- */
.page-about .about-next {
  padding-block: clamp(56px, 9vw, 104px);
  background:
    linear-gradient(135deg, rgba(255, 90, 31, 0.16) 0%, rgba(255, 90, 31, 0) 46%),
    var(--ink);
  border-top: 2px solid var(--flame);
}

.page-about .next-inner {
  max-width: 52em;
}

.page-about .about-next p {
  margin: 0 0 26px;
  font-size: clamp(14.5px, 1.7vw, 16.5px);
  line-height: 1.85;
  color: #d8d2c8;
}

.page-about .next-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

@media (max-width: 420px) {
  .page-about .next-actions .btn {
    width: 100%;
    text-align: center;
  }
}