.page-about {
  --about-green-deep: #1f5c42;
  --about-blue-deep: #1c5571;
  --about-orange-soft: #ffb27d;
  --device-android: #5b7a2d;
  --brown-card: #f7e9da;
  --blue-card: #dfeef3;
  background: var(--page-bg);
  color: var(--text-body);
  font-family: var(--font-body);
  line-height: 1.7;
  scroll-behavior: smooth;
}

.page-about .container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 24px 20px 72px;
}

.page-about .breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-size: 14px;
  margin-bottom: 18px;
  background: rgba(255, 243, 224, 0.65);
  border-radius: var(--radius-pill);
  padding: 8px 16px;
  width: fit-content;
}

.page-about .breadcrumb__item {
  color: var(--text-dark);
  text-decoration: none;
  font-weight: 700;
}

.page-about .breadcrumb__item[aria-current="page"] {
  color: var(--section-green);
}

.page-about .breadcrumb__sep {
  color: var(--border);
}

.page-about .about-hero {
  position: relative;
  overflow: hidden;
  background:
    radial-gradient(circle at 90% 10%, rgba(255, 178, 125, 0.35) 0, transparent 38%),
    linear-gradient(135deg, var(--section-green) 0%, var(--about-green-deep) 100%);
  color: #fdf8f0;
  border-radius: var(--radius-lg);
  padding: 40px 28px 36px;
  margin-bottom: 22px;
  box-shadow: var(--shadow-lift);
}

.page-about .about-hero::after {
  content: "PROFILE";
  position: absolute;
  right: 18px;
  top: 18px;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.32em;
  color: rgba(255, 255, 255, 0.42);
  writing-mode: vertical-rl;
}

.page-about .about-hero__kicker {
  display: inline-block;
  background: var(--accent-orange);
  color: #fff;
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.14em;
  padding: 6px 14px;
  border-radius: var(--radius-pill);
  margin-bottom: 18px;
}

.page-about .about-hero h1 {
  font-family: var(--font-title);
  font-size: 30px;
  line-height: 1.28;
  font-weight: 900;
  margin: 0 0 14px;
  max-width: 820px;
  letter-spacing: 0.01em;
  color: #fff;
}

.page-about .about-hero__lead {
  font-size: 16px;
  color: rgba(255, 248, 240, 0.92);
  max-width: 860px;
  margin: 0;
}

.page-about .hero-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
  margin: 28px 0 0;
  padding: 20px 22px;
  background: rgba(255, 255, 255, 0.12);
  border-radius: var(--radius-md);
  border: 1px solid rgba(255, 255, 255, 0.22);
  max-width: 620px;
}

.page-about .hero-stats div {
  display: flex;
  flex-direction: column;
}

.page-about .hero-stats dt {
  font-family: var(--font-mono);
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.14em;
  color: rgba(255, 248, 240, 0.75);
}

.page-about .hero-stats dd {
  font-family: var(--font-mono);
  font-size: 30px;
  font-weight: 700;
  color: #fff;
  margin: 2px 0 0;
  line-height: 1.1;
}

.page-about .hero-chart {
  margin: 0 0 44px;
  background: var(--card-cream);
  border-radius: var(--radius-md);
  padding: 10px 10px 12px;
  box-shadow: var(--shadow-soft);
  border: 1px solid var(--border);
}

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

.page-about .hero-chart__cap {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--text-dark);
  text-align: center;
  margin: 10px 0 0;
  letter-spacing: 0.04em;
}

.page-about .about-layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: 32px;
  align-items: start;
}

.page-about .about-toc {
  position: sticky;
  top: 20px;
  background: var(--card-warm);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 20px;
}

.page-about .about-toc__title {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--text-dark);
  margin: 0 0 12px;
}

.page-about .about-toc nav {
  display: flex;
  gap: 10px;
  overflow-x: auto;
  padding-bottom: 4px;
}

.page-about .about-toc a {
  white-space: nowrap;
  text-decoration: none;
  font-family: var(--font-title);
  font-weight: 700;
  font-size: 15px;
  color: var(--text-dark);
  background: var(--card-cream);
  border-radius: var(--radius-pill);
  padding: 8px 16px;
  border: 1px solid var(--border);
  transition: background 0.25s ease, color 0.25s ease, transform 0.25s ease;
}

.page-about .about-toc a:hover,
.page-about .about-toc a:focus {
  background: var(--accent-orange);
  color: #fff;
  transform: translateY(-2px);
  border-color: var(--accent-orange);
}

.page-about .about-main {
  display: flex;
  flex-direction: column;
  gap: 44px;
}

.page-about .about-section {
  border-radius: var(--radius-lg);
  padding: 28px 24px;
  box-shadow: var(--shadow-soft);
}

.page-about .about-section__head {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 20px;
}

.page-about .about-section__num {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 15px;
  padding: 6px 14px;
  border-radius: var(--radius-pill);
  color: #fff;
  background: var(--section-green);
  line-height: 1.4;
  flex-shrink: 0;
}

.page-about .about-section h2 {
  font-family: var(--font-title);
  font-size: 26px;
  font-weight: 900;
  color: var(--text-dark);
  margin: 0;
  letter-spacing: 0.01em;
}

.page-about .about-section__lead {
  font-size: 16px;
  margin: 0 0 20px;
  color: var(--text-body);
}

/* 分区背景色与文字适配 */
.page-about .about-section--green {
  background: linear-gradient(180deg, var(--card-light-green) 0%, #f6fbf3 100%);
  border: 1px solid #d3e8d0;
}

.page-about .about-section--green .about-section__num {
  background: var(--section-green);
}

.page-about .about-section--brown {
  background: linear-gradient(135deg, var(--section-brown) 0%, #6e4228 100%);
  border: 1px solid rgba(255, 255, 255, 0.16);
  color: rgba(255, 248, 240, 0.92);
}

.page-about .about-section--brown .about-section__head h2,
.page-about .about-section--blue .about-section__head h2 {
  color: #fff;
}

.page-about .about-section--brown .about-section__lead,
.page-about .about-section--blue .about-section__lead {
  color: rgba(255, 248, 240, 0.9);
}

.page-about .about-section--brown .about-section__num {
  background: var(--card-warm);
  color: var(--text-dark);
}

.page-about .about-section--blue {
  background: linear-gradient(135deg, var(--section-blue) 0%, var(--about-blue-deep) 100%);
  border: 1px solid rgba(255, 255, 255, 0.16);
  color: rgba(255, 248, 240, 0.92);
}

.page-about .about-section--blue .about-section__num {
  background: var(--accent-orange);
}

.page-about .about-section--warm {
  background: linear-gradient(180deg, #fff3e0 0%, #fff8ef 100%);
  border: 1px solid #f0d9b8;
}

.page-about .about-section--warm .about-section__num {
  background: var(--accent-orange);
}

.page-about .about-section--cream {
  background: var(--card-cream);
  border: 1px solid var(--border);
}

.page-about .about-section--cream .about-section__num {
  background: var(--section-brown);
}

.page-about .about-section--cream .devices-table-wrap,
.page-about .about-section--cream .devices-summary {
  background: var(--card-warm);
}

/* 收录范围 */
.page-about .scope-grid {
  display: grid;
  gap: 20px;
  grid-template-columns: 1fr;
}

.page-about .scope-total {
  position: relative;
  overflow: hidden;
  background: linear-gradient(145deg, var(--section-green), var(--about-green-deep));
  color: #fff;
  border-radius: var(--radius-md);
  padding: 32px 28px;
  display: flex;
  flex-direction: column;
  justify-content: center;
  min-height: 226px;
}

.page-about .scope-total::after {
  content: "2416";
  position: absolute;
  right: -12px;
  bottom: -30px;
  font-family: var(--font-mono);
  font-size: 110px;
  font-weight: 700;
  line-height: 1;
  color: rgba(255, 255, 255, 0.06);
  letter-spacing: -0.04em;
}

.page-about .scope-total__num {
  font-family: var(--font-mono);
  font-size: 64px;
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.02em;
  position: relative;
  z-index: 1;
}

.page-about .scope-total__label {
  font-family: var(--font-title);
  font-size: 16px;
  font-weight: 700;
  margin-top: 8px;
  position: relative;
  z-index: 1;
}

.page-about .scope-total p {
  font-size: 14px;
  color: rgba(255, 255, 255, 0.82);
  margin: 18px 0 0;
  max-width: 320px;
  position: relative;
  z-index: 1;
}

.page-about .scope-structure {
  background: var(--card-warm);
  border-radius: var(--radius-md);
  border: 1px solid var(--border);
  padding: 24px;
}

.page-about .scope-structure h3 {
  font-family: var(--font-title);
  font-size: 18px;
  font-weight: 800;
  margin: 0 0 18px;
  color: var(--text-dark);
}

.page-about .scope-structure ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.page-about .scope-structure li {
  display: grid;
  grid-template-columns: 88px 1fr auto;
  align-items: center;
  gap: 12px;
  border-bottom: 1px dashed var(--border);
  padding-bottom: 12px;
}

.page-about .scope-structure li:last-child {
  border-bottom: 0;
  padding-bottom: 0;
}

.page-about .season-tag {
  background: var(--card-light-green);
  border-radius: var(--radius-sm);
  font-family: var(--font-title);
  font-weight: 700;
  font-size: 13px;
  color: var(--section-green);
  padding: 6px 10px;
  text-align: center;
}

.page-about .season-count {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 16px;
  color: var(--text-dark);
}

.page-about .season-status {
  font-size: 12px;
  color: var(--state-done);
  font-weight: 700;
  background: #ededed;
  border-radius: var(--radius-pill);
  padding: 4px 10px;
  white-space: nowrap;
}

.page-about .season-status.is-live {
  color: var(--state-updating);
  background: #fff0db;
}

/* 分类体系 */
.page-about .taxonomy-wrap {
  display: grid;
  grid-template-columns: 1fr;
  gap: 20px;
}

.page-about .taxonomy-card-img {
  background: var(--card-cream);
  border-radius: var(--radius-md);
  padding: 10px;
  border: 1px solid rgba(255, 248, 240, 0.35);
  margin: 0;
}

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

.page-about .taxonomy-card-img figcaption {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--text-dark);
  text-align: center;
  margin: 10px 0 2px;
}

.page-about .taxonomy-tree {
  display: grid;
  gap: 12px;
}

.page-about .taxonomy-tree details {
  background: var(--brown-card);
  border-radius: var(--radius-sm);
  border: 1px solid rgba(255, 248, 240, 0.4);
  padding: 12px 16px;
}

.page-about .taxonomy-tree summary {
  list-style: none;
  cursor: pointer;
  font-family: var(--font-title);
  font-weight: 800;
  font-size: 15px;
  color: var(--text-dark);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  padding: 2px 0;
}

.page-about .taxonomy-tree summary::-webkit-details-marker {
  display: none;
}

.page-about .taxonomy-tree summary::after {
  content: "+";
  font-family: var(--font-mono);
  font-size: 18px;
  font-weight: 700;
  color: var(--accent-orange);
}

.page-about .taxonomy-tree details[open] summary::after {
  content: "−";
}

.page-about .taxonomy-tree ul {
  list-style: none;
  margin: 12px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 8px;
}

.page-about .taxonomy-tree li {
  font-size: 14px;
  background: var(--card-cream);
  border-radius: var(--radius-sm);
  padding: 8px 12px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  color: var(--text-dark);
}

.page-about .taxonomy-tree li strong {
  font-family: var(--font-mono);
  font-size: 14px;
  font-weight: 700;
  color: var(--accent-blue);
}

.page-about .taxonomy-tree .taxonomy-langs {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
}

.page-about .taxonomy-note {
  margin: 12px 0 0;
  font-size: 14px;
  color: var(--text-dark);
}

/* 更新机制 */
.page-about .timeline {
  display: flex;
  flex-direction: column;
  gap: 20px;
  position: relative;
  margin: 28px 0;
  padding-left: 24px;
}

.page-about .timeline::before {
  content: "";
  position: absolute;
  left: 7px;
  top: 8px;
  bottom: 8px;
  width: 3px;
  background: rgba(255, 255, 255, 0.3);
  border-radius: var(--radius-pill);
}

.page-about .timeline__item {
  position: relative;
}

.page-about .timeline__dot {
  position: absolute;
  left: -22px;
  top: 14px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--card-warm);
  border: 3px solid var(--section-blue);
  z-index: 1;
}

.page-about .timeline__item.is-current .timeline__dot {
  background: var(--accent-orange);
  border-color: #fff;
  box-shadow: 0 0 0 5px rgba(242, 122, 43, 0.25);
}

.page-about .timeline__card {
  background: rgba(255, 255, 255, 0.12);
  border: 1px solid rgba(255, 255, 255, 0.22);
  border-radius: var(--radius-md);
  padding: 18px 22px;
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 6px 16px;
  align-items: center;
}

.page-about .timeline__badge {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  color: var(--section-blue);
  background: var(--card-warm);
  border-radius: var(--radius-pill);
  padding: 5px 12px;
  display: inline-block;
  width: fit-content;
}

.page-about .timeline__count {
  font-family: var(--font-mono);
  font-size: 18px;
  font-weight: 700;
  color: var(--accent-orange);
  justify-self: end;
}

.page-about .timeline__desc {
  font-size: 14px;
  color: rgba(255, 255, 255, 0.85);
  grid-column: 1 / -1;
  margin: 4px 0 0;
}

.page-about .timeline-figure {
  margin: 26px 0 0;
  background: rgba(255, 255, 255, 0.12);
  border-radius: var(--radius-md);
  padding: 10px;
  border: 1px solid rgba(255, 255, 255, 0.2);
}

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

.page-about .timeline-figure figcaption {
  font-family: var(--font-mono);
  font-size: 12px;
  color: rgba(255, 255, 255, 0.75);
  text-align: center;
  margin: 10px 0 2px;
}

.page-about .updates-cta {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 20px;
}

.page-about .updates-cta .btn {
  margin: 0;
}

.page-about .btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-title);
  font-weight: 800;
  font-size: 15px;
  line-height: 1.2;
  text-decoration: none;
  padding: 12px 24px;
  border-radius: var(--radius-pill);
  border: 2px solid transparent;
  transition: background 0.25s ease, border-color 0.25s ease, transform 0.25s ease;
}

.page-about .btn--orange {
  background: var(--accent-orange);
  border-color: var(--accent-orange);
  color: #fff;
}

.page-about .btn--orange:hover,
.page-about .btn--orange:focus {
  background: #d9620f;
  border-color: #d9620f;
  transform: translateY(-2px);
}

.page-about .btn--outline {
  background: transparent;
  border-color: rgba(255, 255, 255, 0.7);
  color: #fff;
}

.page-about .btn--outline:hover,
.page-about .btn--outline:focus {
  background: rgba(255, 255, 255, 0.14);
  border-color: #fff;
  transform: translateY(-2px);
}

/* 检索与浏览方式 */
.page-about .steps-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 18px;
}

.page-about .step-card {
  background: var(--card-cream);
  border-radius: var(--radius-md);
  border: 1px solid var(--border);
  padding: 24px;
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.page-about .step-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lift);
}

.page-about .step-card__num {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--accent-orange);
  color: #fff;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 18px;
  margin-bottom: 16px;
}

.page-about .step-card--green .step-card__num {
  background: var(--section-green);
}

.page-about .step-card--orange .step-card__num {
  background: var(--accent-orange);
}

.page-about .step-card--blue .step-card__num {
  background: var(--accent-blue);
}

.page-about .step-card h3 {
  font-family: var(--font-title);
  font-size: 18px;
  font-weight: 800;
  margin: 0 0 10px;
  color: var(--text-dark);
}

.page-about .step-card p {
  font-size: 15px;
  color: var(--text-body);
  margin: 0 0 14px;
}

.page-about .step-card a {
  color: var(--accent-blue);
  font-weight: 700;
  text-decoration: none;
  border-bottom: 2px solid transparent;
  transition: border-color 0.2s ease;
}

.page-about .step-card a:hover,
.page-about .step-card a:focus {
  border-bottom-color: var(--accent-blue);
}

/* 终端适配 */
.page-about .devices-table-wrap {
  overflow-x: auto;
  background: var(--card-cream);
  border-radius: var(--radius-md);
  border: 1px solid var(--border);
}

.page-about .devices-table {
  width: 100%;
  min-width: 640px;
  border-collapse: collapse;
}

.page-about .devices-table th {
  font-family: var(--font-mono);
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--text-dark);
  text-align: left;
  padding: 14px 16px;
  border-bottom: 2px solid var(--border);
  background: var(--card-warm);
}

.page-about .devices-table td {
  padding: 14px 16px;
  border-bottom: 1px solid #efe4d2;
  font-size: 15px;
  color: var(--text-body);
  vertical-align: middle;
}

.page-about .devices-table tr:last-child td {
  border-bottom: 0;
}

.page-about .device-badge {
  display: inline-block;
  font-family: var(--font-title);
  font-weight: 800;
  font-size: 13px;
  padding: 6px 14px;
  border-radius: var(--radius-pill);
  white-space: nowrap;
}

.page-about .device-badge--web {
  background: var(--card-light-green);
  color: var(--section-green);
}

.page-about .device-badge--ios {
  background: #e1f5f2;
  color: var(--section-blue);
}

.page-about .device-badge--android {
  background: #eaf1e0;
  color: var(--device-android);
}

.page-about .device-badge--tv {
  background: var(--card-warm);
  color: var(--section-brown);
}

.page-about .devices-summary {
  margin: 16px 0 0;
  font-size: 14px;
  color: var(--text-body);
  background: var(--card-warm);
  border-radius: var(--radius-sm);
  padding: 16px 18px;
}

/* 底部联络 */
.page-about .about-end-cta {
  background: linear-gradient(135deg, #f27a2b 0%, #d9620f 100%);
  border-radius: var(--radius-lg);
  padding: 32px 28px;
  color: #fff;
  display: flex;
  flex-direction: column;
  gap: 20px;
  align-items: flex-start;
  box-shadow: var(--shadow-lift);
}

.page-about .about-end-cta__mark {
  display: inline-block;
  background: rgba(255, 255, 255, 0.2);
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  border-radius: var(--radius-pill);
  padding: 5px 12px;
  margin-bottom: 10px;
}

.page-about .about-end-cta h2 {
  font-family: var(--font-title);
  font-size: 22px;
  font-weight: 900;
  margin: 0 0 8px;
  color: #fff;
}

.page-about .about-end-cta p {
  font-size: 15px;
  color: rgba(255, 255, 255, 0.9);
  margin: 0;
}

.page-about .about-end-cta .btn {
  background: #fff;
  border-color: #fff;
  color: var(--accent-orange);
}

.page-about .about-end-cta .btn:hover,
.page-about .about-end-cta .btn:focus {
  background: rgba(255, 255, 255, 0.88);
  border-color: rgba(255, 255, 255, 0.88);
  transform: translateY(-2px);
}

.page-about a:focus-visible,
.page-about summary:focus-visible {
  outline: 3px solid var(--focus-ring);
  outline-offset: 2px;
}

@media (min-width: 900px) {
  .page-about .about-hero {
    padding: 64px 56px 52px;
  }

  .page-about .about-hero h1 {
    font-size: 44px;
    line-height: 1.2;
  }

  .page-about .about-hero__lead {
    font-size: 18px;
  }

  .page-about .hero-stats {
    padding: 24px 28px;
  }

  .page-about .hero-stats dd {
    font-size: 36px;
  }

  .page-about .about-layout {
    grid-template-columns: 220px 1fr;
    gap: 40px;
  }

  .page-about .about-toc nav {
    flex-direction: column;
    gap: 10px;
    overflow: visible;
  }

  .page-about .about-toc a {
    text-align: left;
    padding: 10px 14px;
  }

  .page-about .about-main {
    gap: 56px;
  }

  .page-about .about-section {
    padding: 40px 36px;
  }

  .page-about .about-section h2 {
    font-size: 30px;
  }

  .page-about .scope-grid {
    grid-template-columns: 360px 1fr;
    gap: 24px;
  }

  .page-about .taxonomy-wrap {
    grid-template-columns: 300px 1fr;
    gap: 28px;
    align-items: start;
  }

  .page-about .steps-grid {
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
  }

  .page-about .about-end-cta {
    flex-direction: row;
    align-items: center;
    justify-content: space-between;
    gap: 32px;
    padding: 40px 44px;
  }

  .page-about .about-end-cta__text {
    max-width: 640px;
  }

  .page-about .about-end-cta h2 {
    font-size: 26px;
  }
}