/* ===== 全站基础变量 ===== */
:root {
  --c-bg: #ffffff;
  --c-bg-soft: #f6f8fc;
  --c-bg-section: #f9fafc;
  --c-ink: #0b1a2b;
  --c-ink-soft: #3c4a5c;
  --c-ink-muted: #6b7a8c;
  --c-line: #e6ebf2;
  --c-primary: #1e5bff;
  --c-primary-deep: #0038b8;
  --c-accent: #00c2a8;
  --c-warn: #ff7a1a;
  --c-card: #ffffff;
  --shadow-sm: 0 2px 8px rgba(11, 26, 43, 0.04);
  --shadow-md: 0 8px 24px rgba(11, 26, 43, 0.06);
  --shadow-lg: 0 20px 48px rgba(11, 26, 43, 0.10);
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 22px;
  --maxw: 1240px;
}
* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: 'Inter', 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'PingFang SC', 'Microsoft YaHei', sans-serif;
  color: var(--c-ink);
  background: var(--c-bg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}
img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
.container { max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }
.btn { display: inline-flex; align-items: center; justify-content: center; gap: 6px; padding: 10px 18px; border-radius: 10px; font-size: 14px; font-weight: 600; transition: all .2s; cursor: pointer; border: 1px solid transparent; }
.btn-primary { background: var(--c-primary); color: #fff; }
.btn-primary:hover { background: var(--c-primary-deep); transform: translateY(-1px); box-shadow: 0 8px 18px rgba(30, 91, 255, 0.25); }
.btn-outline { background: #fff; color: var(--c-ink); border-color: var(--c-line); }
.btn-outline:hover { border-color: var(--c-primary); color: var(--c-primary); }
.btn-ghost { background: transparent; color: var(--c-ink-soft); }
.btn-ghost:hover { color: var(--c-primary); }
.btn-lg { padding: 14px 26px; font-size: 15px; }

/* ===== 顶部导航 ===== */
.nav {
  position: sticky; top: 0; z-index: 100;
  background: rgba(255,255,255,0.92); backdrop-filter: saturate(180%) blur(12px);
  -webkit-backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid var(--c-line);
}
.nav-inner { display: flex; align-items: center; justify-content: space-between; height: 68px; }
.logo { display: flex; align-items: center; gap: 10px; font-weight: 700; font-size: 17px; }
.logo-mark {
  width: 32px; height: 32px; border-radius: 50%;
  background: url("logo-guoruan.png") center / contain no-repeat #fff;
  color: transparent; font-size: 0; display: grid; place-items: center;
  box-shadow: 0 2px 10px rgba(30, 91, 255, 0.22);
}
.nav-menu { display: flex; align-items: center; gap: 34px; }
.nav-menu > a, .nav-dd-trigger { color: var(--c-ink-soft); font-size: 15px; font-weight: 500; position: relative; padding: 6px 0; transition: color .2s ease; cursor: pointer; }
.nav-menu > a:hover, .nav-dd-trigger:hover { color: var(--c-primary); }
.nav-actions { display: flex; align-items: center; gap: 12px; }

/* ===== 导航下拉 ===== */
.nav-dd { position: relative; }
.nav-dd-trigger { display: inline-flex; align-items: center; gap: 4px; }
.caret { font-size: 11px; transition: transform .2s; }
.nav-dd.open .caret { transform: rotate(180deg); }
.nav-dd-panel {
  position: absolute; top: 100%; left: -16px; min-width: 320px;
  background: #fff; border: 1px solid var(--c-line); border-radius: var(--radius-md);
  box-shadow: var(--shadow-lg); padding: 8px; opacity: 0; visibility: hidden;
  transform: translateY(6px); transition: opacity .18s ease, transform .18s ease, visibility .18s;
  z-index: 99;
}
.nav-dd:hover .nav-dd-panel, .nav-dd.open .nav-dd-panel { opacity: 1; visibility: visible; transform: translateY(0); }
.nav-dd-panel a {
  display: flex; align-items: center; gap: 14px; padding: 12px 14px; border-radius: 10px;
  color: var(--c-ink); font-size: 14px; transition: background .15s ease;
}
.nav-dd-panel a:hover { background: var(--c-bg-soft); color: var(--c-primary); }
.nav-dd-panel a strong { display: block; font-size: 14px; font-weight: 600; }
.nav-dd-panel a small { display: block; color: var(--c-ink-muted); font-size: 12px; margin-top: 2px; font-weight: 400; }
.dd-icon {
  width: 36px; height: 36px; border-radius: 10px; flex-shrink: 0;
  display: flex; align-items: center; justify-content: center;
  font-weight: 700; font-size: 14px;
}

/* ===== 汉堡 ===== */
.hamburger {
  display: none; flex-direction: column; justify-content: center; gap: 5px;
  width: 40px; height: 40px; border: 1px solid var(--c-line); background: #fff;
  border-radius: 10px; cursor: pointer; padding: 0; align-items: center;
}
.hamburger span { display: block; width: 20px; height: 2px; background: var(--c-ink); border-radius: 1px; transition: transform .2s, opacity .2s; }
.hamburger.active span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.hamburger.active span:nth-child(2) { opacity: 0; }
.hamburger.active span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ===== 内页组件 ===== */
.page-hero { padding: 80px 0 48px; background: linear-gradient(180deg, var(--c-bg-soft), #fff); border-bottom: 1px solid var(--c-line); }
.breadcrumb { font-size: 13px; color: var(--c-ink-muted); margin-bottom: 18px; }
.breadcrumb a { color: var(--c-ink-muted); }
.breadcrumb a:hover { color: var(--c-primary); }
.breadcrumb span { color: var(--c-ink); font-weight: 500; }
.page-hero h1 { font-size: 44px; font-weight: 800; letter-spacing: -0.02em; line-height: 1.2; }
.page-hero .lead { color: var(--c-ink-soft); font-size: 17px; margin-top: 14px; max-width: 760px; }

.feature-list { display: grid; grid-template-columns: repeat(2, 1fr); gap: 18px; margin-top: 36px; }
.feature-item { padding: 22px; background: #fff; border: 1px solid var(--c-line); border-radius: var(--radius-md); transition: border-color .2s, transform .2s; }
.feature-item:hover { border-color: var(--c-primary); transform: translateY(-2px); }
.feature-item h4 { font-size: 16px; font-weight: 700; margin-bottom: 8px; display: flex; align-items: center; gap: 8px; }
.feature-item p { font-size: 14px; color: var(--c-ink-soft); line-height: 1.7; }
.feature-icon { width: 32px; height: 32px; border-radius: 8px; display: inline-flex; align-items: center; justify-content: center; background: #eef4ff; color: var(--c-primary); font-size: 14px; font-weight: 700; }
.feature-icon.green { background: #eaf8f5; color: var(--c-accent); }
.feature-icon.orange { background: #fff3e8; color: var(--c-warn); }

.related-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; margin-top: 36px; }
.related-card { padding: 20px; background: var(--c-bg-soft); border-radius: var(--radius-md); border: 1px solid var(--c-line); transition: all .2s; display: block; }
.related-card:hover { background: #fff; border-color: var(--c-primary); transform: translateY(-2px); box-shadow: var(--shadow-sm); }
.related-card .tag { font-size: 12px; color: var(--c-primary); font-weight: 600; margin-bottom: 8px; display: block; }
.related-card h5 { font-size: 15px; font-weight: 700; color: var(--c-ink); margin-bottom: 6px; }
.related-card p { font-size: 13px; color: var(--c-ink-soft); }

.page-section { padding: 64px 0; }
.page-section + .page-section { border-top: 1px solid var(--c-line); }
.page-section h2 { font-size: 32px; font-weight: 800; letter-spacing: -0.01em; }
.page-section h2 + .lead { color: var(--c-ink-soft); font-size: 16px; margin-top: 12px; max-width: 720px; }

.sub-nav { display: flex; flex-wrap: wrap; gap: 8px; margin-bottom: 32px; }
.sub-nav a { padding: 8px 14px; border-radius: 999px; background: var(--c-bg-soft); font-size: 13px; color: var(--c-ink-soft); border: 1px solid var(--c-line); }
.sub-nav a:hover, .sub-nav a.active { background: var(--c-primary); color: #fff; border-color: var(--c-primary); }

.quote-block { background: linear-gradient(135deg, #f6f8fc, #eaf1fa); border-left: 4px solid var(--c-primary); padding: 24px 28px; border-radius: 0 var(--radius-md) var(--radius-md) 0; margin: 28px 0; font-size: 15px; color: var(--c-ink-soft); font-style: italic; }
.quote-block cite { display: block; font-size: 13px; color: var(--c-ink-muted); font-style: normal; margin-top: 10px; }

.stat-strip { display: grid; grid-template-columns: repeat(4, 1fr); gap: 0; margin: 32px 0; background: #fff; border: 1px solid var(--c-line); border-radius: var(--radius-md); overflow: hidden; }
.stat-strip .cell { padding: 24px; text-align: center; border-right: 1px solid var(--c-line); }
.stat-strip .cell:last-child { border-right: none; }
.stat-strip .num { font-size: 32px; font-weight: 800; color: var(--c-primary); }
.stat-strip .lbl { font-size: 13px; color: var(--c-ink-muted); margin-top: 6px; }

.product-overview-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; margin-top: 36px; }
.product-overview-card { padding: 26px; background: #fff; border: 1px solid var(--c-line); border-radius: var(--radius-md); transition: all .25s; display: block; }
.product-overview-card:hover { border-color: var(--c-primary); transform: translateY(-2px); box-shadow: var(--shadow-md); }
.product-overview-card .icon-tag { display: inline-block; padding: 4px 10px; border-radius: 6px; font-size: 12px; font-weight: 600; margin-bottom: 14px; }
.product-overview-card h4 { font-size: 18px; font-weight: 700; margin-bottom: 8px; }
.product-overview-card p { color: var(--c-ink-soft); font-size: 14px; margin-bottom: 16px; }
.product-overview-card .arrow { color: var(--c-primary); font-size: 13px; font-weight: 600; }

.section-eyebrow { display: inline-block; padding: 5px 12px; background: rgba(30,91,255,0.08); color: var(--c-primary); font-size: 12px; font-weight: 700; border-radius: 999px; letter-spacing: 0.06em; text-transform: uppercase; margin-bottom: 14px; }
.section-head { text-align: center; max-width: 720px; margin: 0 auto 40px; }
.section-head h2 { font-size: 38px; font-weight: 800; letter-spacing: -0.02em; line-height: 1.2; }
.section-head .lead { color: var(--c-ink-soft); font-size: 16px; margin-top: 14px; }

.case-detail-hero { padding: 64px 0 32px; background: var(--c-bg-soft); border-bottom: 1px solid var(--c-line); }
.case-detail-hero .industry-tag { display: inline-block; padding: 5px 12px; background: rgba(30,91,255,0.10); color: var(--c-primary); border-radius: 6px; font-size: 12px; font-weight: 700; margin-bottom: 16px; }
.case-detail-hero h1 { font-size: 38px; font-weight: 800; letter-spacing: -0.02em; line-height: 1.25; }
.case-detail-hero .lead { color: var(--c-ink-soft); font-size: 16px; margin-top: 14px; max-width: 760px; }
.case-meta-strip { display: flex; flex-wrap: wrap; gap: 28px; margin-top: 24px; padding-top: 24px; border-top: 1px solid var(--c-line); }
.case-meta-strip .item { font-size: 13px; color: var(--c-ink-muted); }
.case-meta-strip .item strong { display: block; color: var(--c-ink); font-size: 18px; font-weight: 700; margin-top: 4px; }

.two-col { display: grid; grid-template-columns: 1fr 1fr; gap: 40px; align-items: start; }
.two-col.reverse > :first-child { order: 2; }

.module-list { list-style: none; margin-top: 24px; }
.module-list li { padding: 16px 0; border-bottom: 1px solid var(--c-line); display: flex; gap: 14px; align-items: flex-start; }
.module-list li::before { content: ''; flex-shrink: 0; width: 8px; height: 8px; border-radius: 50%; background: var(--c-primary); margin-top: 10px; }
.module-list li strong { display: block; margin-bottom: 4px; font-size: 15px; }
.module-list li span { color: var(--c-ink-soft); font-size: 14px; line-height: 1.7; }

.cta-banner {
  margin: 64px 0; padding: 48px;
  background: linear-gradient(135deg, #1e5bff 0%, #0038b8 100%);
  border-radius: var(--radius-lg); color: #fff; text-align: center;
}
.cta-banner h2 { font-size: 30px; font-weight: 800; margin-bottom: 12px; }
.cta-banner p { font-size: 15px; opacity: 0.9; max-width: 600px; margin: 0 auto 24px; }
.cta-banner .btn-primary { background: #fff; color: var(--c-primary); }
.cta-banner .btn-primary:hover { background: #f6f8fc; }
.cta-banner .btn-outline { background: transparent; color: #fff; border-color: rgba(255,255,255,0.4); margin-left: 8px; }
.cta-banner .btn-outline:hover { background: rgba(255,255,255,0.10); border-color: #fff; }

/* ===== 页脚 ===== */
.foot { background: #0b1a2b; color: #c8d2e0; padding: 64px 0 32px; }
.foot-grid { display: grid; grid-template-columns: 1.6fr 1fr 1fr 1fr 1fr; gap: 36px; margin-bottom: 48px; }
.foot-brand .logo { color: #fff; margin-bottom: 16px; }
.foot-brand p { color: #8b97a8; font-size: 13px; line-height: 1.7; }
.foot-col h6 { color: #fff; font-size: 14px; font-weight: 700; margin-bottom: 18px; }
.foot-col ul { list-style: none; }
.foot-col li { margin-bottom: 10px; }
.foot-col a { color: #8b97a8; font-size: 13px; transition: color .2s; }
.foot-col a:hover { color: #fff; }
.foot-bottom { padding-top: 28px; border-top: 1px solid rgba(255,255,255,0.08); display: flex; justify-content: space-between; flex-wrap: wrap; gap: 12px; font-size: 12px; color: #6b7a8c; }
.foot-bottom > div:last-child { white-space: nowrap; }
.foot-bottom img { display: inline; vertical-align: -3px; margin-right: 4px; }

/* ===== 响应式 ===== */
@media (max-width: 1024px) {
  .nav-menu { gap: 20px; }
  .nav-menu > a, .nav-dd-trigger { font-size: 14px; }
  .nav-actions .nav-login { display: none; }
  .product-overview-grid, .related-grid { grid-template-columns: repeat(2, 1fr); }
  .foot-grid { grid-template-columns: 1fr 1fr; gap: 32px; }
  .two-col { grid-template-columns: 1fr; gap: 24px; }
  .two-col.reverse > :first-child { order: 0; }
}
@media (max-width: 880px) {
  .page-hero h1 { font-size: 30px; }
  .page-hero { padding: 56px 0 36px; }
  .page-section { padding: 48px 0; }
  .feature-list, .product-overview-grid, .related-grid { grid-template-columns: 1fr; }
  .stat-strip { grid-template-columns: 1fr 1fr; }
  .stat-strip .cell { border-right: none; border-bottom: 1px solid var(--c-line); }
  .stat-strip .cell:nth-child(odd) { border-right: 1px solid var(--c-line); }
  .section-head h2 { font-size: 28px; }
  .cta-banner { padding: 32px 20px; margin: 40px 0; }
  .cta-banner h2 { font-size: 24px; }
  .case-detail-hero h1 { font-size: 26px; }
  .nav-menu { display: none; position: absolute; top: 68px; left: 0; right: 0; background: #fff; flex-direction: column; align-items: stretch; padding: 12px 0; gap: 0; border-top: 1px solid var(--c-line); box-shadow: var(--shadow-md); max-height: calc(100vh - 68px); overflow-y: auto; }
  .nav-menu.open { display: flex; }
  .nav-menu > a, .nav-dd-trigger { padding: 14px 24px; border-bottom: 1px solid var(--c-line); font-size: 16px; }
  .nav-dd-panel { position: static; opacity: 1; visibility: visible; transform: none; box-shadow: none; border: none; padding: 0 0 8px 24px; min-width: 0; background: var(--c-bg-soft); display: none; }
  .nav-dd.open .nav-dd-panel { display: block; }
  .nav-dd-panel a { padding: 12px 24px; gap: 12px; }
  .hamburger { display: flex; }
  .nav-cta { display: none; }
  .foot-grid { grid-template-columns: 1fr; gap: 32px; }
}

/* ===== FAQ 模块 ===== */
.faq-list { display: grid; grid-template-columns: repeat(2, 1fr); gap: 16px; margin-top: 32px; }
.faq-item { background: #fff; border: 1px solid var(--c-line); border-radius: var(--radius-md); padding: 22px 24px; transition: border-color .2s; }
.faq-item:hover { border-color: var(--c-primary); }
.faq-q { font-size: 15.5px; font-weight: 700; line-height: 1.55; margin: 0 0 10px; display: flex; gap: 10px; align-items: flex-start; color: var(--c-ink); }
.faq-q::before {
  content: 'Q'; flex: none; width: 22px; height: 22px; border-radius: 6px; margin-top: 2px;
  background: linear-gradient(135deg, var(--c-primary), var(--c-accent));
  color: #fff; font-size: 12px; font-weight: 800;
  display: flex; align-items: center; justify-content: center;
}
.faq-a { margin: 0; padding-left: 32px; color: var(--c-ink-soft); font-size: 14px; line-height: 1.85; }
.faq-a p { margin: 0 0 10px; }
.faq-a p:last-child { margin-bottom: 0; }

/* ===== 文章详情页 ===== */
.article-hero { padding: 72px 0 40px; background: linear-gradient(180deg, var(--c-bg-soft), #fff); border-bottom: 1px solid var(--c-line); }
.article-hero h1 { font-size: 38px; font-weight: 800; letter-spacing: -0.02em; line-height: 1.3; max-width: 880px; }
.article-hero .lead { color: var(--c-ink-soft); font-size: 16.5px; margin-top: 16px; max-width: 820px; line-height: 1.75; }
.article-cat { display: inline-block; padding: 5px 12px; border-radius: 6px; font-size: 12px; font-weight: 700; margin-bottom: 16px; }
.article-meta { display: flex; flex-wrap: wrap; gap: 20px; margin-top: 22px; padding-top: 20px; border-top: 1px solid var(--c-line); font-size: 13px; color: var(--c-ink-muted); }

.article-body { max-width: 820px; }
.article-body > h2 { font-size: 25px; font-weight: 800; letter-spacing: -0.01em; margin: 44px 0 6px; line-height: 1.4; }
.article-body > h2:first-child { margin-top: 0; }
.article-body > h3 { font-size: 18px; font-weight: 700; margin: 30px 0 10px; color: var(--c-ink); }
.article-body p { font-size: 15.5px; line-height: 1.9; color: var(--c-ink-soft); margin-bottom: 16px; }
.article-body strong { color: var(--c-ink); font-weight: 700; }
.article-body ul, .article-body ol { margin: 0 0 18px 22px; }
.article-body li { font-size: 15.5px; line-height: 1.85; color: var(--c-ink-soft); margin-bottom: 9px; }
.article-body a { color: var(--c-primary); text-decoration: underline; text-underline-offset: 3px; }
.article-body table { width: 100%; border-collapse: collapse; margin: 20px 0; font-size: 14px; }
.article-body th { background: var(--c-bg-soft); text-align: left; padding: 11px 14px; font-weight: 700; font-size: 13.5px; border: 1px solid var(--c-line); color: var(--c-ink); }
.article-body td { padding: 11px 14px; border: 1px solid var(--c-line); color: var(--c-ink-soft); vertical-align: top; }
.article-body .key-point {
  background: linear-gradient(135deg, #f6f8fc, #eef5ff);
  border-left: 4px solid var(--c-primary);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  padding: 20px 24px; margin: 24px 0;
}
.article-body .key-point h4 { font-size: 15px; font-weight: 700; margin-bottom: 10px; color: var(--c-ink); }
.article-body .key-point ul { margin-bottom: 0; }
.article-body .key-point li:last-child { margin-bottom: 0; }
.article-body .src-note { font-size: 13px; color: var(--c-ink-muted); line-height: 1.75; border-top: 1px dashed var(--c-line); padding-top: 16px; margin-top: 32px; }
.article-body .brand-note { margin-top: 40px; padding: 20px 22px; background: var(--c-bg-soft); border-left: 3px solid var(--c-primary); border-radius: 0 var(--radius-md) var(--radius-md) 0; }
.article-body .brand-note p { font-size: 13.5px; line-height: 1.8; color: var(--c-ink-muted); margin: 0; }
.article-body .brand-note p + p { margin-top: 10px; }
.article-body .brand-note strong { color: var(--c-ink); }
.article-body .brand-note a { color: var(--c-primary); font-size: 13.5px; text-decoration: none; margin-right: 16px; }
.article-body .brand-note a:hover { text-decoration: underline; }

/* ===== 资讯列表页 ===== */
.news-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; margin-top: 32px; }
.news-card { padding: 24px; background: #fff; border: 1px solid var(--c-line); border-radius: var(--radius-md); transition: all .25s; display: flex; flex-direction: column; }
.news-card:hover { border-color: var(--c-primary); transform: translateY(-2px); box-shadow: var(--shadow-md); }
.news-card .icon-tag { display: inline-block; padding: 4px 10px; border-radius: 6px; font-size: 12px; font-weight: 600; margin-bottom: 14px; align-self: flex-start; }
.news-card h4 { font-size: 16.5px; font-weight: 700; margin-bottom: 10px; line-height: 1.45; }
.news-card p { color: var(--c-ink-soft); font-size: 13.5px; line-height: 1.7; margin-bottom: 14px; flex: 1; }
.news-card .meta { display: flex; gap: 14px; color: var(--c-ink-muted); font-size: 12px; }

@media (max-width: 1024px) {
  .news-grid { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 880px) {
  .faq-list, .news-grid { grid-template-columns: 1fr; }
  .article-hero { padding: 52px 0 32px; }
  .article-hero h1 { font-size: 26px; }
  .article-body > h2 { font-size: 21px; margin-top: 34px; }
  .article-body p, .article-body li { font-size: 15px; }
}