/* ============================================================
   七维教育 · 特教知识中心 — 样式表
   继承 products.css 的设计系统，扩展文章阅读体验
   ============================================================ */

:root {
  --ink: #18344f;
  --ink-strong: #102a43;
  --muted: #61758a;
  --subtle: #8a9caf;
  --line: #dce6ef;
  --surface: #ffffff;
  --surface-soft: #f5f8fb;
  --surface-blue: #eef7fd;
  --blue: #247ec2;
  --blue-dark: #17689f;
  --sky: #63b2e7;
  --green: #2f8f6b;
  --amber: #b77724;
  --coral: #c85f55;
  --shadow-sm: 0 8px 24px rgba(24, 52, 79, 0.08);
  --shadow-lg: 0 22px 58px rgba(24, 52, 79, 0.14);
  --content: 1200px;
  --reading: 780px;
  --header-height: 72px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: calc(var(--header-height) + 28px); }

body {
  margin: 0;
  background: var(--surface);
  color: var(--ink);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  font-size: 16px;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

a { color: inherit; text-decoration: none; }
button, input { font: inherit; }
button { cursor: pointer; }
img { max-width: 100%; }

a:focus-visible,
button:focus-visible { outline: 2px solid var(--sky); outline-offset: 2px; }

.skip-link {
  position: fixed; top: 8px; left: 8px; z-index: 200;
  padding: 8px 12px; transform: translateY(-150%);
  border-radius: 4px; background: var(--ink-strong); color: #fff;
}
.skip-link:focus { transform: translateY(0); }

/* ============================================================
   HEADER — 复用产品页导航
   ============================================================ */
.site-header {
  position: sticky; top: 0; z-index: 90;
  min-height: var(--header-height);
  border-bottom: 1px solid rgba(220, 230, 239, 0.9);
  background: rgba(255, 255, 255, 0.96);
  backdrop-filter: blur(14px);
}

.nav-wrap {
  width: min(var(--content), calc(100% - 40px));
  min-height: var(--header-height);
  margin: 0 auto;
  display: flex; align-items: center; justify-content: space-between; gap: 28px;
}

.brand {
  display: inline-flex; align-items: center; gap: 10px;
  flex: 0 0 auto; color: var(--ink-strong);
  font-size: 1.08rem; font-weight: 800;
}
.brand img { width: 38px; height: 38px; border-radius: 6px; object-fit: cover; }

.main-nav { display: flex; align-items: center; gap: 28px; }
.main-nav a {
  position: relative; padding: 22px 0 20px;
  color: #40576e; font-size: 0.92rem; font-weight: 650;
}
.main-nav a:hover,
.main-nav a[aria-current="page"] { color: var(--blue); }
.main-nav a[aria-current="page"]::after {
  content: ""; position: absolute; right: 0; bottom: 15px; left: 0;
  height: 2px; background: var(--sky);
}

.nav-contact {
  min-height: 38px; padding: 7px 15px !important;
  border: 1px solid #bed5e8; border-radius: 6px;
  color: var(--blue) !important;
}
.nav-contact::after { display: none !important; }

.nav-toggle {
  display: none; width: 42px; height: 42px;
  border: 1px solid var(--line); border-radius: 6px;
  background: #fff; color: var(--ink); font-size: 1.35rem;
}

.page-width {
  width: min(var(--content), calc(100% - 40px));
  margin: 0 auto;
}

.eyebrow {
  display: block; margin-bottom: 12px;
  color: var(--blue); font-size: 0.8rem; font-weight: 800;
  letter-spacing: 0.05em;
}

/* ============================================================
   BREADCRUMB
   ============================================================ */
.breadcrumb {
  display: flex; align-items: center; gap: 6px; flex-wrap: wrap;
  margin-bottom: 28px; color: var(--subtle);
  font-size: 0.82rem; font-weight: 500;
}
.breadcrumb a { color: var(--muted); }
.breadcrumb a:hover { color: var(--blue); }
.breadcrumb span[aria-current] { color: var(--ink); }

/* ============================================================
   ARTICLE HERO
   ============================================================ */
.article-hero {
  padding: 56px 0 48px;
  border-bottom: 1px solid var(--line);
  background: var(--surface-soft);
}

.article-hero .cluster-tag {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 5px 14px; margin-bottom: 18px;
  border-radius: 50px; background: var(--surface-blue);
  color: var(--blue-dark); font-size: 0.8rem; font-weight: 700;
}
.article-hero .cluster-tag svg { width: 14px; height: 14px; flex-shrink: 0; }

.article-hero h1 {
  margin: 0 0 22px;
  color: var(--ink-strong);
  font-size: clamp(1.8rem, 3.5vw, 2.6rem);
  line-height: 1.25;
  letter-spacing: -0.01em;
  text-wrap: balance;
}

.article-summary {
  max-width: var(--reading);
  margin: 0 0 24px;
  padding: 16px 20px;
  border-left: 3px solid var(--sky);
  border-radius: 0 8px 8px 0;
  background: rgba(99, 178, 231, 0.08);
  color: var(--ink);
  font-size: 0.98rem;
  line-height: 1.85;
}

.article-meta {
  display: flex; align-items: center; flex-wrap: wrap; gap: 20px;
  color: var(--subtle); font-size: 0.82rem;
}
.article-meta .author-badge {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 4px 14px 4px 4px;
  border-radius: 50px; background: var(--surface);
  border: 1px solid var(--line);
  color: var(--ink); font-weight: 600;
}
.article-meta .author-badge .avatar {
  width: 28px; height: 28px; border-radius: 50%;
  background: linear-gradient(135deg, var(--sky), var(--blue));
  color: #fff; font-size: 0.7rem; font-weight: 700;
  display: flex; align-items: center; justify-content: center;
}
.article-meta span { display: inline-flex; align-items: center; gap: 4px; }
.article-meta svg { width: 14px; height: 14px; color: var(--subtle); }

/* ============================================================
   ARTICLE READING AREA (main + sidebar)
   ============================================================ */
.article-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 260px;
  gap: 56px;
  padding: 48px 0 72px;
}

/* --- TOC Sidebar --- */
.toc-sidebar {
  position: sticky; top: calc(var(--header-height) + 28px);
  align-self: start;
  max-height: calc(100vh - var(--header-height) - 56px);
  overflow-y: auto;
  padding: 24px 0;
}

.toc-sidebar h2 {
  margin: 0 0 16px;
  color: var(--subtle);
  font-size: 0.75rem; font-weight: 800;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.toc-sidebar ol {
  list-style: none; margin: 0; padding: 0;
  border-left: 2px solid var(--line);
}
.toc-sidebar li { margin: 0; }
.toc-sidebar a {
  display: block; padding: 7px 0 7px 18px;
  margin-left: -2px;
  border-left: 2px solid transparent;
  color: var(--muted); font-size: 0.84rem; font-weight: 500;
  line-height: 1.5;
  transition: color 0.18s ease, border-color 0.18s ease;
}
.toc-sidebar a:hover { color: var(--ink); }
.toc-sidebar a.is-active {
  color: var(--blue-dark); border-left-color: var(--blue);
  font-weight: 650;
}

.toc-sidebar .toc-related {
  margin-top: 32px;
  padding-top: 24px;
  border-top: 1px solid var(--line);
}

.toc-sidebar .toc-related h3 {
  margin: 0 0 12px;
  color: var(--subtle); font-size: 0.75rem; font-weight: 800;
  letter-spacing: 0.08em;
}
.toc-sidebar .toc-related a {
  padding: 6px 0; border-left: none; margin-left: 0;
  color: var(--blue); font-size: 0.82rem;
}
.toc-sidebar .toc-related a:hover { color: var(--blue-dark); }
.toc-sidebar .toc-related .coming-link {
  display: block;
  padding: 6px 0;
  color: var(--muted);
  font-size: 0.82rem;
  line-height: 1.5;
}
.toc-sidebar .toc-related .coming-link small {
  color: var(--subtle);
  font-size: 0.72rem;
  white-space: nowrap;
}

/* ============================================================
   READING PROGRESS BAR
   ============================================================ */
.reading-progress {
  position: fixed; top: var(--header-height); left: 0; right: 0;
  height: 3px; z-index: 89; background: transparent;
}
.reading-progress .bar {
  height: 100%; width: 0;
  background: linear-gradient(90deg, var(--sky), var(--blue));
  transition: width 0.1s linear;
}

/* ============================================================
   ARTICLE BODY — 正文排版
   ============================================================ */
.article-body {
  max-width: var(--reading);
  min-width: 0;
}

.article-body h2 {
  margin: 48px 0 18px;
  padding-top: 32px;
  border-top: 1px solid var(--line);
  color: var(--ink-strong);
  font-size: 1.45rem;
  line-height: 1.35;
}
.article-body h2:first-child { margin-top: 0; padding-top: 0; border-top: none; }

.article-body h3 {
  margin: 32px 0 12px;
  color: var(--ink);
  font-size: 1.12rem;
  line-height: 1.4;
}

.article-body p {
  margin: 0 0 18px;
  color: var(--ink);
  font-size: 1rem;
  line-height: 1.85;
}

.article-body ul,
.article-body ol {
  margin: 0 0 20px;
  padding-left: 24px;
}
.article-body li {
  margin-bottom: 8px;
  line-height: 1.8;
}
.article-body li::marker { color: var(--blue); }

.article-body blockquote {
  margin: 24px 0;
  padding: 16px 20px;
  border-left: 3px solid var(--sky);
  border-radius: 0 8px 8px 0;
  background: var(--surface-blue);
  color: var(--ink);
  font-size: 0.96rem;
  line-height: 1.85;
}
.article-body blockquote p { margin: 0 0 8px; }
.article-body blockquote p:last-child { margin: 0; }

.article-body strong { font-weight: 700; color: var(--ink-strong); }

/* --- Tables --- */
.article-body table {
  width: 100%; margin: 24px 0;
  border-collapse: collapse;
  font-size: 0.92rem;
}
.article-body thead { background: var(--surface-soft); }
.article-body th {
  padding: 12px 16px;
  text-align: left;
  font-weight: 700;
  color: var(--ink-strong);
  border-bottom: 2px solid var(--line);
}
.article-body td {
  padding: 11px 16px;
  border-bottom: 1px solid var(--line);
  vertical-align: top;
  line-height: 1.65;
}
.article-body tr:hover td { background: rgba(238, 247, 253, 0.5); }

/* --- Inline links --- */
.article-body a {
  color: var(--blue);
  text-decoration: underline;
  text-decoration-color: rgba(36, 126, 194, 0.3);
  text-underline-offset: 3px;
  transition: text-decoration-color 0.18s ease;
}
.article-body a:hover { text-decoration-color: var(--blue); }

/* --- Key Takeaways box --- */
.key-takeaways {
  margin: 0 0 36px;
  padding: 24px 28px;
  border-radius: 12px;
  background: linear-gradient(135deg, #eef7fd 0%, #f5f8fb 100%);
  border: 1px solid #d4e8f5;
}
.key-takeaways h2 {
  margin: 0 0 14px !important;
  padding: 0 !important;
  border: none !important;
  color: var(--blue-dark);
  font-size: 1.1rem;
}
.key-takeaways ul {
  margin: 0; padding-left: 20px;
}
.key-takeaways li {
  margin-bottom: 6px;
  color: var(--ink);
  font-size: 0.95rem;
  line-height: 1.75;
}

/* --- Caution / Warning boxes --- */
.caution-box {
  margin: 24px 0;
  padding: 18px 22px;
  border-radius: 10px;
  border: 1px solid #f5dbd8;
  background: #fef8f7;
}
.caution-box .caution-title {
  display: flex; align-items: center; gap: 8px;
  margin-bottom: 10px;
  color: var(--coral); font-weight: 700; font-size: 0.92rem;
}
.caution-box .caution-title svg { width: 18px; height: 18px; }
.caution-box ul { margin: 0; padding-left: 20px; }
.caution-box li { margin-bottom: 4px; font-size: 0.92rem; line-height: 1.7; color: var(--ink); }

/* ============================================================
   FAQ ACCORDION
   ============================================================ */
.faq-section {
  margin: 48px 0 0;
  padding-top: 36px;
  border-top: 1px solid var(--line);
}

.faq-section h2 {
  margin: 0 0 20px !important;
  padding: 0 !important;
  border: none !important;
}

.faq-item {
  border: 1px solid var(--line);
  border-radius: 10px;
  margin-bottom: 10px;
  overflow: hidden;
  transition: border-color 0.2s ease;
}
.faq-item:hover { border-color: #bdd5e9; }

.faq-question {
  display: flex; align-items: center; justify-content: space-between;
  width: 100%; padding: 16px 20px;
  border: none; background: var(--surface-soft);
  color: var(--ink-strong); font-size: 0.96rem; font-weight: 650;
  text-align: left; cursor: pointer;
  transition: background 0.18s ease;
}
.faq-question:hover { background: var(--surface-blue); }

.faq-question .faq-icon {
  flex-shrink: 0; width: 20px; height: 20px;
  transition: transform 0.25s ease;
  color: var(--blue);
}
.faq-item.is-open .faq-icon { transform: rotate(45deg); }

.faq-answer {
  max-height: 0; overflow: hidden;
  transition: max-height 0.3s ease, padding 0.3s ease;
}
.faq-item.is-open .faq-answer {
  max-height: 400px;
}
.faq-answer-inner {
  padding: 0 20px 18px;
  color: var(--ink); font-size: 0.94rem; line-height: 1.8;
}

/* ============================================================
   REFERENCES
   ============================================================ */
.references-section {
  margin: 36px 0 0;
  padding-top: 28px;
  border-top: 1px solid var(--line);
}
.references-section h2 {
  margin: 0 0 14px !important; padding: 0 !important; border: none !important;
  font-size: 1.1rem;
}
.references-section ol {
  margin: 0; padding-left: 20px; counter-reset: ref;
}
.references-section li {
  margin-bottom: 10px; font-size: 0.88rem;
  line-height: 1.7; color: var(--muted);
}
.references-section li a { color: var(--blue); text-decoration: underline; text-underline-offset: 2px; }

/* ============================================================
   RELATED ARTICLES BAND
   ============================================================ */
.related-band {
  padding: 64px 0;
  background: var(--surface-soft);
  border-top: 1px solid var(--line);
}

.related-band h2 {
  margin: 0 0 8px;
  color: var(--ink-strong);
  font-size: 1.5rem;
}
.related-band .related-subtitle {
  margin: 0 0 32px;
  color: var(--muted); font-size: 0.96rem;
}

.related-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 20px;
}

.related-card {
  display: flex; flex-direction: column;
  padding: 24px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: var(--surface);
  transition: border-color 0.2s ease, box-shadow 0.2s ease, transform 0.2s ease;
}
.related-card:hover {
  border-color: #bdd5e9;
  box-shadow: var(--shadow-sm);
  transform: translateY(-3px);
}
.related-card.is-coming-soon {
  cursor: default;
}
.related-card.is-coming-soon:hover {
  border-color: var(--line);
  box-shadow: none;
  transform: none;
}

.related-card .card-cluster {
  display: inline-block;
  margin-bottom: 12px;
  padding: 3px 10px;
  border-radius: 50px;
  background: var(--surface-blue);
  color: var(--blue-dark);
  font-size: 0.72rem; font-weight: 700;
}

.related-card h3 {
  margin: 0 0 10px;
  color: var(--ink-strong);
  font-size: 1rem; font-weight: 700;
  line-height: 1.45;
}

.related-card p {
  flex: 1;
  margin: 0 0 16px;
  color: var(--muted); font-size: 0.86rem; line-height: 1.7;
}

.related-card .card-link {
  display: inline-flex; align-items: center; gap: 4px;
  color: var(--blue); font-size: 0.86rem; font-weight: 650;
}
.related-card.is-coming-soon .card-link { color: var(--subtle); }
.related-card .card-link span { transition: transform 0.2s ease; }
.related-card:hover .card-link span { transform: translateX(4px); }

/* ============================================================
   PRODUCT RECOMMENDATION (如文章关联产品)
   ============================================================ */
.product-rec {
  margin: 36px 0;
  padding: 24px 28px;
  border: 1px solid #d4e2ed;
  border-radius: 12px;
  background: linear-gradient(135deg, #f5f8fb 0%, #eef7fd 100%);
  display: flex; align-items: center; gap: 24px;
}
.product-rec .rec-icon {
  flex-shrink: 0; width: 48px; height: 48px;
  border-radius: 10px;
  background: var(--blue); color: #fff;
  display: flex; align-items: center; justify-content: center;
}
.product-rec .rec-icon svg { width: 24px; height: 24px; }
.product-rec .rec-body { flex: 1; }
.product-rec .rec-body strong {
  display: block; margin-bottom: 4px;
  color: var(--ink-strong); font-size: 0.96rem;
}
.product-rec .rec-body p { margin: 0; color: var(--muted); font-size: 0.88rem; line-height: 1.65; }
.product-rec .rec-link {
  flex-shrink: 0;
  padding: 8px 18px;
  border-radius: 6px;
  background: var(--blue);
  color: #fff;
  font-size: 0.86rem; font-weight: 650;
  transition: background 0.2s ease;
}
.product-rec .rec-link:hover { background: var(--blue-dark); text-decoration: none; }

/* ============================================================
   FOOTER — 复用产品页 footer
   ============================================================ */
.site-footer {
  border-top: 1px solid var(--line);
  background: var(--ink-strong);
  color: rgba(255, 255, 255, 0.7);
  padding: 48px 0 0;
}
.site-footer h2 {
  color: #fff; font-size: 1.15rem; margin: 0 0 10px;
}
.site-footer h3 {
  color: rgba(255, 255, 255, 0.5);
  font-size: 0.78rem; font-weight: 700;
  letter-spacing: 0.06em;
  margin: 0 0 14px;
}
.site-footer a {
  display: block; padding: 4px 0;
  color: rgba(255, 255, 255, 0.65);
  font-size: 0.88rem;
}
.site-footer a:hover { color: #fff; }

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr;
  gap: 40px;
  padding-bottom: 32px;
}

.footer-bottom {
  padding: 16px 0;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  font-size: 0.78rem;
  color: rgba(255, 255, 255, 0.4);
}

/* ============================================================
   CONTACT FLOATING BUTTON + MODAL
   ============================================================ */
.floating-contact {
  position: fixed; bottom: 28px; right: 28px; z-index: 80;
  min-height: 48px; padding: 0 24px;
  border: none; border-radius: 50px;
  background: var(--blue);
  color: #fff; font-size: 0.92rem; font-weight: 700;
  box-shadow: 0 8px 28px rgba(36, 126, 194, 0.35);
  transition: background 0.2s ease, transform 0.2s ease;
}
.floating-contact:hover { background: var(--blue-dark); transform: translateY(-2px); }

.modal-backdrop {
  position: fixed; inset: 0; z-index: 100;
  display: flex; align-items: center; justify-content: center;
  background: rgba(16, 42, 67, 0.5);
  backdrop-filter: blur(6px);
  opacity: 0; pointer-events: none;
  transition: opacity 0.25s ease;
}
.modal-backdrop.is-open { opacity: 1; pointer-events: auto; }

.contact-dialog {
  width: min(460px, calc(100% - 40px));
  max-height: 85vh; overflow-y: auto;
  border-radius: 16px; background: var(--surface);
  box-shadow: var(--shadow-lg);
}

.dialog-header {
  display: flex; align-items: flex-start; justify-content: space-between;
  padding: 24px 28px 0;
}
.dialog-header h2 { margin: 0 0 4px; color: var(--ink-strong); font-size: 1.2rem; }
.dialog-header p { margin: 0; color: var(--muted); font-size: 0.88rem; }

.icon-button {
  width: 36px; height: 36px; border: 1px solid var(--line); border-radius: 8px;
  background: var(--surface-soft); color: var(--ink);
  font-size: 1.2rem; display: flex; align-items: center; justify-content: center;
  transition: background 0.15s ease;
}
.icon-button:hover { background: var(--surface-blue); }

.contact-options {
  display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px;
  padding: 20px 28px 28px;
}
.contact-option {
  text-align: center; padding: 12px;
  border: 1px solid var(--line); border-radius: 10px;
  background: var(--surface-soft);
}
.contact-option img { width: 100%; max-width: 140px; margin: 0 auto 10px; border-radius: 6px; }
.contact-option strong { display: block; color: var(--ink-strong); font-size: 0.88rem; }
.contact-option span { display: block; color: var(--subtle); font-size: 0.75rem; margin-top: 2px; }

/* Lightbox */
.lightbox {
  position: fixed; inset: 0; z-index: 110;
  display: flex; align-items: center; justify-content: center;
  background: rgba(16, 42, 67, 0.75);
  backdrop-filter: blur(8px);
  opacity: 0; pointer-events: none;
  transition: opacity 0.25s ease;
}
.lightbox.is-open { opacity: 1; pointer-events: auto; }
.lightbox-inner { position: relative; max-width: 480px; width: 90%; }
.lightbox-inner img { width: 100%; border-radius: 12px; }
.lightbox-inner .icon-button {
  position: absolute; top: -16px; right: -16px;
  background: var(--surface); box-shadow: var(--shadow-sm);
}
.lightbox-caption {
  text-align: center; padding: 12px;
  color: rgba(255, 255, 255, 0.8); font-size: 0.86rem;
}

/* ============================================================
   KNOWLEDGE LISTING PAGE
   ============================================================ */
.listing-hero {
  padding: 56px 0 48px;
  border-bottom: 1px solid var(--line);
  background: var(--surface-soft);
}
.listing-hero h1 {
  margin: 0 0 14px; color: var(--ink-strong);
  font-size: clamp(2rem, 4vw, 3rem); line-height: 1.2;
}
.listing-hero p {
  max-width: 640px; margin: 0;
  color: var(--muted); font-size: 1.05rem; line-height: 1.8;
}

.listing-stats {
  display: flex; gap: 32px; margin-top: 24px;
}
.listing-stat {
  display: flex; align-items: baseline; gap: 6px;
}
.listing-stat .num {
  color: var(--blue); font-size: 1.6rem; font-weight: 800;
}
.listing-stat .label { color: var(--muted); font-size: 0.88rem; }

/* Cluster filter bar */
.cluster-bar {
  position: sticky; top: var(--header-height); z-index: 70;
  border-bottom: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.97);
  box-shadow: 0 12px 28px -22px rgba(24, 52, 79, 0.2);
}
.cluster-bar-inner {
  width: min(var(--content), calc(100% - 40px));
  margin: 0 auto;
  display: flex; align-items: center; gap: 6px;
  min-height: 58px;
  overflow-x: auto;
  scrollbar-width: none;
}
.cluster-bar-inner::-webkit-scrollbar { display: none; }

.cluster-btn {
  flex: 0 0 auto;
  min-height: 34px; padding: 5px 14px;
  border: 1px solid transparent; border-radius: 6px;
  background: transparent;
  color: #536a81; font-size: 0.85rem; font-weight: 650;
  transition: background 0.18s ease, color 0.18s ease, border-color 0.18s ease;
}
.cluster-btn:hover { background: var(--surface-soft); color: var(--ink); }
.cluster-btn.is-active {
  border-color: #a9cee9; background: var(--surface-blue);
  color: var(--blue-dark);
}

/* Article list */
.article-list {
  padding: 48px 0 72px;
}

.cluster-group { margin-bottom: 48px; }
.cluster-group:last-child { margin-bottom: 0; }

.cluster-group-title {
  display: flex; align-items: center; gap: 12px;
  margin: 0 0 6px;
  padding-bottom: 14px;
  border-bottom: 2px solid var(--line);
}
.cluster-group-title h2 {
  margin: 0; color: var(--ink-strong);
  font-size: 1.25rem;
}

/* Dense row list layout */
.article-dense-list {
  display: flex;
  flex-direction: column;
}

.article-row {
  display: grid;
  grid-template-columns: 48px 1fr 28px;
  gap: 14px;
  align-items: center;
  padding: 14px 16px;
  border-bottom: 1px solid var(--line);
  color: var(--ink);
  text-decoration: none;
  transition: background 0.15s ease, padding-left 0.15s ease;
}
.article-row:first-child { border-top: none; }
.article-row:hover {
  background: var(--surface-blue);
  padding-left: 22px;
}
.article-row.is-coming-soon {
  cursor: default;
}
.article-row.is-coming-soon:hover {
  background: transparent;
  padding-left: 16px;
}

.row-type {
  display: inline-flex; align-items: center; justify-content: center;
  min-width: 42px; height: 24px;
  padding: 0 8px;
  border-radius: 4px;
  font-size: 0.68rem; font-weight: 700;
  white-space: nowrap;
  flex-shrink: 0;
}
.row-type.pillar { background: #fef3e2; color: var(--amber); }
.row-type.guide { background: var(--surface-blue); color: var(--blue-dark); }
.row-type.comparison { background: #e8f5e9; color: var(--green); }
.row-type.checklist { background: #fce4ec; color: var(--coral); }
.row-type.opinion { background: #f3e5f5; color: #7b1fa2; }
.row-type.pillar[style] { background: linear-gradient(135deg, #e3f0ff 0%, #f0e6ff 100%); color: var(--blue-dark); }

.row-title {
  color: var(--ink); font-size: 0.94rem; font-weight: 600;
  line-height: 1.5;
  transition: color 0.15s ease;
}
.article-row:hover .row-title { color: var(--blue-dark); }
.article-row.is-coming-soon .row-title,
.article-row.is-coming-soon:hover .row-title { color: var(--muted); }
.row-coming {
  margin-left: 4px;
  color: var(--subtle);
  font-size: 0.78rem;
  font-weight: 500;
  white-space: nowrap;
}

.row-arrow {
  color: var(--subtle); font-size: 0.9rem;
  transition: color 0.15s ease, transform 0.15s ease;
  justify-self: end;
}
.article-row:hover .row-arrow { color: var(--blue); transform: translateX(3px); }

/* ============================================================
   RESPONSIVE — 移动端
   ============================================================ */
@media (max-width: 900px) {
  .article-layout {
    grid-template-columns: 1fr;
    gap: 0;
  }

  .toc-sidebar {
    position: relative; top: 0;
    max-height: none;
    padding: 0 0 24px;
    border-bottom: 1px solid var(--line);
    margin-bottom: 32px;
  }

  .toc-sidebar ol {
    display: flex; flex-wrap: wrap; gap: 6px;
    border-left: none;
  }
  .toc-sidebar a {
    padding: 6px 14px; margin: 0;
    border: 1px solid var(--line); border-left: 1px solid var(--line);
    border-radius: 50px;
    font-size: 0.78rem;
  }
  .toc-sidebar a.is-active {
    background: var(--surface-blue);
    border-color: #a9cee9;
  }

  .toc-sidebar .toc-related { display: none; }
}

@media (max-width: 768px) {
  .nav-toggle { display: flex; align-items: center; justify-content: center; }

  .main-nav {
    position: fixed; top: var(--header-height); left: 0; right: 0;
    flex-direction: column; align-items: stretch; gap: 0;
    padding: 8px 20px 16px;
    border-bottom: 1px solid var(--line);
    background: var(--surface);
    box-shadow: var(--shadow-sm);
    transform: translateY(-120%);
    transition: transform 0.25s ease;
  }
  .main-nav.is-open { transform: translateY(0); }

  .main-nav a {
    padding: 14px 0; border-bottom: 1px solid var(--line);
    font-size: 0.95rem;
  }
  .main-nav a:last-child { border-bottom: none; }
  .nav-contact { text-align: center; margin-top: 8px; }

  .article-hero h1 { font-size: 1.6rem; }

  .article-row { grid-template-columns: 42px 1fr 20px; gap: 10px; padding: 12px 10px; }
  .row-type { font-size: 0.62rem; min-width: 36px; }
  .row-title { font-size: 0.88rem; }

  .footer-grid { grid-template-columns: 1fr; gap: 24px; }

  .contact-options { grid-template-columns: 1fr; }
  .floating-contact { bottom: 20px; right: 20px; }

  .product-rec { flex-direction: column; text-align: center; }
  .product-rec .rec-link { width: 100%; text-align: center; }

  .related-grid { grid-template-columns: 1fr; }
}

@media (max-width: 480px) {
  .article-hero { padding: 36px 0 32px; }
  .article-hero h1 { font-size: 1.4rem; }
  .article-summary { padding: 12px 16px; font-size: 0.92rem; }
  .listing-hero h1 { font-size: 1.6rem; }
  .row-arrow { display: none; }
  .article-row { grid-template-columns: 38px 1fr; }
}