/* ===== 品牌自述页 · 页面专属样式 ===== */

.page-about {
  display: block;
}

/* ---------- 首屏：报头式开场 ---------- */

.page-about .about-mast {
  position: relative;
  isolation: isolate;
  padding: clamp(22px, 4.6vw, 48px) 0 clamp(30px, 5.4vw, 64px);
}

.page-about .about-mast::before {
  content: "";
  position: absolute;
  z-index: -1;
  inset: -70px -35% auto -35%;
  height: 440px;
  background:
    radial-gradient(52% 78% at 22% 0%, rgba(20, 224, 176, .18), transparent 66%),
    radial-gradient(44% 66% at 88% 10%, rgba(255, 90, 46, .13), transparent 70%);
  pointer-events: none;
}

.page-about .about-title {
  margin: 16px 0 0;
  max-width: 20ch;
  font-family: var(--font-display);
  font-style: italic;
  font-weight: 900;
  font-size: clamp(33px, 7vw, 64px);
  line-height: 1.04;
  letter-spacing: -.02em;
  color: var(--paper);
}

.page-about .about-title span {
  font-family: var(--font-mono);
  font-style: normal;
  color: var(--cyan);
  letter-spacing: -.04em;
}

.page-about .about-lede {
  margin: clamp(16px, 2.4vw, 24px) 0 0;
  max-width: 38ch;
  font-size: 17px;
  line-height: 1.85;
  color: var(--cyan-soft);
}

.page-about .about-stats {
  margin-top: clamp(22px, 3.6vw, 34px);
  padding-top: clamp(16px, 3vw, 26px);
  border-top: 1px solid var(--line);
}

/* ---------- 章节索引 ---------- */

.page-about .about-toc {
  margin-top: clamp(20px, 3.4vw, 32px);
}

.page-about .about-toc .toc-title {
  margin: 0 0 10px;
  font-size: 13px;
  letter-spacing: .16em;
  color: var(--muted);
}

.page-about .about-toc .toc-list {
  display: flex;
  flex-wrap: wrap;
  gap: 6px 18px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-toc .toc-link {
  display: inline-block;
  padding-bottom: 2px;
  font-size: 13px;
  letter-spacing: .06em;
  color: var(--muted);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color .2s var(--ease), border-color .2s var(--ease);
}

.page-about .about-toc .toc-link:hover,
.page-about .about-toc .toc-link:focus-visible {
  color: var(--cyan-soft);
}

.page-about .about-toc .toc-link[aria-current="true"] {
  color: var(--cyan);
  border-bottom-color: var(--cyan);
}

/* ---------- 章节标题尺寸收敛 ---------- */

.page-about .section-index {
  font-size: clamp(54px, 12vw, 112px);
}

.page-about .section-title {
  font-size: clamp(26px, 5vw, 40px);
}

/* ---------- 竖向时间线 ---------- */

.page-about .timeline {
  position: relative;
  margin: 0;
  padding: 0 0 0 44px;
  list-style: none;
}

.page-about .timeline::before {
  content: "";
  position: absolute;
  left: 13px;
  top: 10px;
  bottom: 10px;
  width: 1px;
  background: linear-gradient(180deg, rgba(20, 224, 176, .85), rgba(20, 224, 176, .1));
}

.page-about .tline-item {
  position: relative;
  padding-bottom: clamp(20px, 3.6vw, 34px);
}

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

.page-about .tline-item::before {
  content: "";
  position: absolute;
  left: -35px;
  top: 7px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--amber);
  box-shadow: 0 0 0 4px rgba(255, 194, 74, .14);
}

.page-about .tline-year {
  display: block;
  margin-bottom: 6px;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: .1em;
  color: var(--amber);
}

.page-about .tline-title {
  margin: 0 0 6px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 20px;
  letter-spacing: -.01em;
  color: var(--paper);
}

.page-about .tline-body p,
.page-about .tline-details .disclosure-body p {
  margin: 0;
  max-width: 48ch;
  font-size: 16px;
  line-height: 1.85;
  color: var(--muted);
}

.page-about .tline-details > .disclosure-summary {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 20px;
  letter-spacing: -.01em;
  color: var(--paper);
}

/* ---------- 九个观察角度 ---------- */

.page-about .dim-list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0 0 clamp(22px, 4vw, 36px);
  padding: 0;
  list-style: none;
}

.page-about .dim-notes {
  margin-top: 4px;
}

.page-about .dim-notes .card-body p {
  margin: 0;
  font-size: 16px;
  line-height: 1.85;
  color: var(--muted);
}

/* ---------- 制作流程图 ---------- */

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

.page-about .media img {
  display: block;
  width: 100%;
  height: auto;
  border-radius: var(--radius);
}

.page-about .media-caption {
  margin-top: 10px;
  font-size: 13px;
  line-height: 1.7;
  letter-spacing: .04em;
  color: var(--muted);
}

.page-about .flow-figure {
  margin-bottom: clamp(24px, 4vw, 38px);
}

/* ---------- 五步分段切换 ---------- */

.page-about .flow-tabs .tabs-list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0 0 18px;
}

.page-about .flow-tabs .tab {
  padding: 8px 14px;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: .06em;
  color: var(--muted);
  background: transparent;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  cursor: pointer;
  transition: color .2s var(--ease), border-color .2s var(--ease), background-color .2s var(--ease);
}

.page-about .flow-tabs .tab:hover,
.page-about .flow-tabs .tab:focus-visible {
  color: var(--cyan-soft);
  border-color: var(--cyan);
}

.page-about .flow-tabs .tab[aria-selected="true"] {
  color: var(--ink);
  background: var(--cyan);
  border-color: var(--cyan);
}

.page-about .flow-tabs .tab-panel {
  display: block;
  padding: clamp(20px, 3.4vw, 30px);
  background: var(--panel);
  border: 1px solid var(--line);
  border-left: 3px solid var(--flare);
  border-radius: var(--radius);
}

.page-about .flow-tabs .tab-panel[hidden] {
  display: none;
}

.page-about .flow-tabs .tab-panel + .tab-panel {
  margin-top: 12px;
}

.page-about .step-num {
  display: block;
  margin-bottom: 10px;
  font-family: var(--font-mono);
  font-size: 30px;
  line-height: 1;
  color: var(--flare);
}

.page-about .step-title {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 21px;
  letter-spacing: -.01em;
  color: var(--paper);
}

.page-about .flow-tabs .tab-panel p {
  margin: 0;
  max-width: 54ch;
  font-size: 16px;
  line-height: 1.85;
  color: var(--muted);
}

/* ---------- 团队三张错落卡片 ---------- */

.page-about .team-grid {
  display: grid;
  gap: 16px;
  margin-bottom: clamp(26px, 4.4vw, 44px);
}

.page-about .team-card {
  transition: transform .28s var(--ease), border-color .28s var(--ease);
}

.page-about .team-card:hover,
.page-about .team-card:focus-within {
  transform: translateY(-3px);
  border-color: var(--cyan);
}

.page-about .team-card .card-body p {
  margin: 0;
  font-size: 16px;
  line-height: 1.85;
  color: var(--muted);
}

.page-about .team-foot {
  display: flex;
  justify-content: space-between;
  gap: 10px;
  margin: 16px 0 0;
  padding-top: 12px;
  border-top: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .06em;
  color: var(--muted);
  transition: color .28s var(--ease);
}

.page-about .team-card:hover .team-foot,
.page-about .team-card:focus-within .team-foot {
  color: var(--cyan);
}

/* ---------- 三级内容分类阶梯 ---------- */

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

.page-about .ladder-item {
  padding: clamp(18px, 3vw, 26px) clamp(18px, 3vw, 28px);
  background: linear-gradient(90deg, rgba(20, 224, 176, .1), rgba(10, 35, 27, .92) 46%);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.page-about .ladder-num {
  display: block;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: .18em;
  color: var(--cyan);
}

.page-about .ladder-title {
  margin: 8px 0 6px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 20px;
  letter-spacing: -.01em;
  color: var(--paper);
}

.page-about .ladder-item p {
  margin: 0;
  max-width: 50ch;
  font-size: 16px;
  line-height: 1.85;
  color: var(--muted);
}

/* ---------- 周更节奏 ---------- */

.page-about .cadence {
  display: grid;
  gap: 16px;
  margin-bottom: clamp(24px, 4vw, 38px);
}

.page-about .cadence-card {
  padding: clamp(20px, 3.2vw, 28px);
  background: var(--panel-2);
  border: 1px solid var(--line);
  border-top: 2px solid var(--amber);
  border-radius: var(--radius);
}

.page-about .cadence-card:nth-child(2) {
  border-top-color: var(--cyan);
}

.page-about .cadence-day {
  display: block;
  font-family: var(--font-mono);
  font-size: 26px;
  letter-spacing: .04em;
  color: var(--amber);
}

.page-about .cadence-card:nth-child(2) .cadence-day {
  color: var(--cyan);
}

.page-about .cadence-title {
  margin: 10px 0 8px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 20px;
  letter-spacing: -.01em;
  color: var(--paper);
}

.page-about .cadence-card p {
  margin: 0;
  max-width: 46ch;
  font-size: 16px;
  line-height: 1.85;
  color: var(--muted);
}

.page-about .cadence-figure {
  margin-bottom: clamp(20px, 3.4vw, 30px);
}

.page-about .cadence-note {
  margin: 0;
  max-width: 56ch;
  font-size: 16px;
  line-height: 1.9;
  color: var(--muted);
}

.page-about .cadence-note a {
  color: var(--cyan);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.page-about .cadence-note a:hover,
.page-about .cadence-note a:focus-visible {
  color: var(--cyan-soft);
}

/* ---------- 读者画像收尾 ---------- */

.page-about .reader-list {
  margin: 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--line);
}

.page-about .reader-item {
  display: grid;
  gap: 8px;
  padding: clamp(18px, 3vw, 26px) 0;
  border-bottom: 1px solid var(--line);
}

.page-about .reader-title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 19px;
  letter-spacing: -.01em;
  color: var(--paper);
}

.page-about .reader-item p {
  margin: 0;
  max-width: 56ch;
  font-size: 16px;
  line-height: 1.85;
  color: var(--muted);
}

.page-about .reader-cta {
  margin: clamp(24px, 4vw, 38px) 0 0;
  padding-left: 16px;
  max-width: 58ch;
  border-left: 2px solid var(--cyan);
  font-size: 16px;
  line-height: 1.9;
  color: var(--cyan-soft);
}

.page-about .reader-cta a {
  color: var(--cyan);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.page-about .reader-cta a:hover,
.page-about .reader-cta a:focus-visible {
  color: var(--cyan-soft);
}

/* ---------- 窄屏与宽屏适配 ---------- */

@media (max-width: 480px) {
  .page-about .timeline {
    padding-left: 34px;
  }

  .page-about .timeline::before {
    left: 10px;
  }

  .page-about .tline-item::before {
    left: -28px;
  }

  .page-about .flow-tabs .tab {
    padding: 7px 10px;
    font-size: 12px;
  }
}

@media (min-width: 720px) {
  .page-about .tline-item {
    display: grid;
    grid-template-columns: 96px minmax(0, 1fr);
    gap: 22px;
    align-items: start;
  }

  .page-about .tline-item::before {
    top: 14px;
  }

  .page-about .tline-year {
    margin: 0;
    padding-top: 9px;
    text-align: right;
  }

  .page-about .cadence {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 18px;
  }
}

@media (min-width: 780px) {
  .page-about .team-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    align-items: start;
  }

  .page-about .team-card:nth-child(1) {
    margin-top: 42px;
  }

  .page-about .team-card:nth-child(3) {
    margin-top: 18px;
  }

  .page-about .ladder-item:nth-child(2) {
    margin: 0 7% 0 5%;
  }

  .page-about .ladder-item:nth-child(3) {
    margin: 0 14% 0 10%;
  }

  .page-about .reader-item {
    grid-template-columns: minmax(0, 230px) minmax(0, 1fr);
    gap: 28px;
    align-items: baseline;
  }
}

/* ---------- 动效降级 ---------- */

@media (prefers-reduced-motion: reduce) {
  .page-about .team-card,
  .page-about .team-foot,
  .page-about .flow-tabs .tab,
  .page-about .about-toc .toc-link {
    transition: none;
  }

  .page-about .team-card:hover,
  .page-about .team-card:focus-within {
    transform: none;
  }
}