/* ============================================================
   随方信息 WebModeler 官网 v2
   现代企业风 · 默认亮色 · 可切换暗色
   ============================================================ */

/* ---- 主题变量 ---- */
:root, [data-theme="light"] {
  --bg:           #FFFFFF;
  --bg-soft:      #F7F8FA;
  --bg-muted:     #EFF2F6;

  --primary:      #1E5BB8;
  --primary-hover:#1A4E9E;
  --primary-soft: #EDF2FB;
  --accent:       #C97A2E;

  --text:         #1A2233;
  --text-mid:     #4A5468;
  --text-mute:    #6B7689;
  --text-faint:   #98A1B0;
  --text-on-primary: #FFFFFF;

  --line:         #E3E7ED;
  --line-strong:  #CDD3DC;

  --shadow-sm: 0 1px 2px rgba(20,30,50,0.04);
  --shadow:    0 2px 8px rgba(20,30,50,0.06);
  --shadow-lg: 0 12px 32px rgba(20,30,50,0.08);
}

[data-theme="dark"] {
  --bg:           #0F1419;
  --bg-soft:      #161C24;
  --bg-muted:     #1E2731;

  --primary:      #5B8EE8;
  --primary-hover:#7AA6F0;
  --primary-soft: #1A2438;
  --accent:       #D89058;

  --text:         #E4E8EE;
  --text-mid:     #ADB6C2;
  --text-mute:    #7E8898;
  --text-faint:   #5A6371;
  --text-on-primary: #0F1419;

  --line:         #28313D;
  --line-strong:  #394453;

  --shadow-sm: 0 1px 2px rgba(0,0,0,0.3);
  --shadow:    0 2px 8px rgba(0,0,0,0.4);
  --shadow-lg: 0 12px 32px rgba(0,0,0,0.5);
}

:root {
  --font-sans: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", "Helvetica Neue", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "微软雅黑", sans-serif;
}

/* ---- 重置 ---- */
* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
  font-family: var(--font-sans);
  background: var(--bg);
  color: var(--text);
  font-size: 15px;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  transition: background-color 0.2s ease, color 0.2s ease;
}
a {
  color: var(--primary);
  text-decoration: none;
  transition: color 0.15s ease;
}
a:hover { color: var(--primary-hover); }
img, svg { max-width: 100%; display: block; }
h1, h2, h3, h4 {
  font-family: var(--font-sans);
  font-weight: 600;
  color: var(--text);
  letter-spacing: -0.01em;
  line-height: 1.25;
}
h1 { font-weight: 700; letter-spacing: -0.02em; }
button {
  font-family: inherit;
  cursor: pointer;
  border: none;
  background: transparent;
  color: inherit;
}
::selection { background: var(--primary); color: var(--text-on-primary); }

/* ---- 布局 ---- */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 32px;
}
.section { padding: 100px 0; }

/* ---- 导航 ---- */
.nav {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255,255,255,0.85);
  backdrop-filter: saturate(180%) blur(12px);
  -webkit-backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid var(--line);
  transition: background-color 0.2s ease, border-color 0.2s ease;
}
[data-theme="dark"] .nav { background: rgba(15,20,25,0.85); }
.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 32px;
}
.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  color: var(--text);
  font-weight: 600;
  font-size: 17px;
  letter-spacing: -0.01em;
}
.brand:hover { color: var(--text); }
.brand-mark { width: 28px; height: 28px; flex-shrink: 0; }
.nav-links {
  display: flex;
  gap: 4px;
  list-style: none;
  align-items: center;
}
.nav-links a {
  color: var(--text-mid);
  padding: 8px 14px;
  font-size: 14px;
  font-weight: 500;
  border-radius: 6px;
  transition: all 0.15s ease;
}
.nav-links a:hover { color: var(--text); background: var(--bg-soft); }
.nav-links a.active { color: var(--primary); background: var(--primary-soft); }

.nav-actions { display: flex; align-items: center; gap: 12px; }
.theme-toggle {
  width: 36px;
  height: 36px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--line);
  border-radius: 6px;
  color: var(--text-mid);
  transition: all 0.15s ease;
  background: var(--bg);
}
.theme-toggle:hover { color: var(--text); border-color: var(--line-strong); }
.theme-toggle svg { width: 18px; height: 18px; }
.theme-toggle .icon-moon { display: none; }
.theme-toggle .icon-sun { display: block; }
[data-theme="dark"] .theme-toggle .icon-sun { display: none; }
[data-theme="dark"] .theme-toggle .icon-moon { display: block; }

.nav-phone { font-size: 13.5px; color: var(--text-mid); font-variant-numeric: tabular-nums; }
.nav-toggle {
  display: none;
  width: 36px; height: 36px;
  border: 1px solid var(--line);
  border-radius: 6px;
  align-items: center;
  justify-content: center;
  color: var(--text);
}

/* ---- 按钮 ---- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 11px 22px;
  font-size: 14px;
  font-weight: 500;
  border-radius: 6px;
  transition: all 0.15s ease;
  border: 1px solid transparent;
  background: var(--bg-soft);
  color: var(--text);
  white-space: nowrap;
}
.btn:hover { background: var(--bg-muted); color: var(--text); }
.btn-primary {
  background: var(--primary);
  color: var(--text-on-primary);
  border-color: var(--primary);
}
.btn-primary:hover {
  background: var(--primary-hover);
  border-color: var(--primary-hover);
  color: var(--text-on-primary);
}
.btn-outline {
  background: transparent;
  color: var(--text);
  border-color: var(--line-strong);
}
.btn-outline:hover {
  background: var(--bg-soft);
  border-color: var(--text-faint);
  color: var(--text);
}
.btn .arrow { transition: transform 0.15s ease; }
.btn:hover .arrow { transform: translateX(3px); }

/* ---- Hero ---- */
.hero { padding: 96px 0 64px; position: relative; }
.hero-inner {
  max-width: 880px;
  margin: 0 auto;
  padding: 0 32px;
}
.hero-eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-size: 13px;
  font-weight: 500;
  color: var(--primary);
  margin-bottom: 24px;
  padding: 5px 14px;
  background: var(--primary-soft);
  border-radius: 100px;
}
.hero-eyebrow::before {
  content: "";
  width: 6px; height: 6px;
  border-radius: 50%;
  background: var(--primary);
}
.hero-title {
  font-size: clamp(36px, 5vw, 60px);
  line-height: 1.1;
  letter-spacing: -0.025em;
  margin-bottom: 28px;
  font-weight: 700;
  color: var(--text);
}
.hero-title .accent { color: var(--primary); }
.hero-desc {
  font-size: 18px;
  line-height: 1.65;
  color: var(--text-mid);
  margin-bottom: 36px;
  max-width: 60ch;
}
.hero-actions { display: flex; gap: 12px; flex-wrap: wrap; }
.hero-facts {
  margin-top: 80px;
  max-width: 880px;
  margin-left: auto;
  margin-right: auto;
  padding: 40px 32px 0;
  display: flex;
  flex-wrap: wrap;
  gap: 40px 64px;
  border-top: 1px solid var(--line);
}
.hero-fact {
  flex: 0 0 auto;
  min-width: 120px;
}
.hero-fact .v {
  font-size: 28px;
  font-weight: 600;
  color: var(--text);
  line-height: 1;
  letter-spacing: -0.02em;
  margin-bottom: 8px;
  font-variant-numeric: tabular-nums;
  white-space: nowrap;
}
.hero-fact .k {
  font-size: 13px;
  color: var(--text-mute);
  white-space: nowrap;
}

/* ---- section 标题 ---- */
.section-head {
  max-width: 720px;
  margin: 0 auto 64px;
  text-align: center;
}
.section-head.left { margin-left: 0; text-align: left; }
.section-head .eyebrow {
  font-size: 13px;
  font-weight: 500;
  color: var(--primary);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 14px;
  display: block;
}
.section-head h2 {
  font-size: clamp(28px, 3.5vw, 40px);
  line-height: 1.2;
  margin-bottom: 16px;
  letter-spacing: -0.02em;
  font-weight: 700;
}
.section-head p {
  font-size: 17px;
  color: var(--text-mid);
  line-height: 1.6;
  max-width: 60ch;
  margin: 0 auto;
}
.section-head.left p { margin: 0; }

/* ---- 能力区 ---- */
.cap-section { background: var(--bg-soft); }
.cap-grid { display: flex; flex-wrap: wrap; gap: 24px; }
.cap {
  flex: 1 1 280px;
  min-width: 260px;
  padding: 32px;
  background: var(--bg);
  border: 1px solid var(--line);
  border-radius: 12px;
  transition: all 0.2s ease;
}
.cap:hover {
  border-color: var(--line-strong);
  box-shadow: var(--shadow);
  transform: translateY(-2px);
}
.cap-icon {
  width: 44px; height: 44px;
  border-radius: 8px;
  background: var(--primary-soft);
  color: var(--primary);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
}
.cap-icon svg { width: 22px; height: 22px; stroke-width: 1.75; }
.cap h3 { font-size: 18px; margin-bottom: 10px; font-weight: 600; }
.cap p {
  color: var(--text-mid);
  font-size: 14.5px;
  line-height: 1.65;
}

/* ---- 架构区 ---- */
.arch-row {
  display: flex;
  flex-wrap: wrap;
  gap: 64px;
  align-items: center;
}
.arch-text { flex: 1 1 380px; min-width: 0; }
.arch-visual { flex: 1 1 380px; min-width: 0; }
.arch-text h2 {
  font-size: clamp(28px, 3vw, 36px);
  margin-bottom: 20px;
  line-height: 1.2;
  letter-spacing: -0.02em;
}
.arch-text p {
  font-size: 16px;
  color: var(--text-mid);
  line-height: 1.7;
  margin-bottom: 20px;
}
.arch-text ul { list-style: none; margin: 24px 0; }
.arch-text ul li {
  padding: 10px 0;
  padding-left: 28px;
  position: relative;
  color: var(--text);
  font-size: 15px;
}
.arch-text ul li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 18px;
  width: 16px;
  height: 2px;
  background: var(--primary);
}

.arch-stack {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 24px;
  background: var(--bg-soft);
  border-radius: 12px;
  border: 1px solid var(--line);
}
.arch-layer {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 18px 20px;
  background: var(--bg);
  border-radius: 8px;
  border: 1px solid var(--line);
  transition: all 0.2s ease;
}
.arch-layer:hover {
  border-color: var(--primary);
  transform: translateX(4px);
}
.arch-layer .layer-tag {
  font-size: 11px;
  font-weight: 600;
  color: var(--primary);
  letter-spacing: 0.05em;
  width: 28px;
  flex-shrink: 0;
}
.arch-layer .layer-name {
  font-weight: 500;
  color: var(--text);
  flex: 1;
  font-size: 15px;
}
.arch-layer .layer-meta {
  font-size: 12px;
  color: var(--text-mute);
}

/* ---- 场景卡片 ---- */
.scenarios { background: var(--bg-soft); }
.scenario-grid { display: flex; flex-wrap: wrap; gap: 24px; }
.scenario-card {
  flex: 1 1 380px;
  min-width: 280px;
  padding: 36px 32px;
  background: var(--bg);
  border: 1px solid var(--line);
  border-radius: 12px;
  display: flex;
  flex-direction: column;
  transition: all 0.2s ease;
  text-decoration: none;
  color: inherit;
}
.scenario-card:hover {
  border-color: var(--line-strong);
  box-shadow: var(--shadow-lg);
  transform: translateY(-3px);
  color: inherit;
}
.scenario-tag {
  font-size: 12px;
  font-weight: 500;
  color: var(--primary);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 14px;
}
.scenario-card h3 {
  font-size: 22px;
  margin-bottom: 12px;
  font-weight: 600;
  letter-spacing: -0.01em;
}
.scenario-card > p {
  color: var(--text-mid);
  font-size: 15px;
  line-height: 1.65;
  margin-bottom: 24px;
  flex: 1;
}
.scenario-footer {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-top: 16px;
  border-top: 1px solid var(--line);
}
.scenario-keys { display: flex; gap: 8px; flex-wrap: wrap; }
.scenario-keys span {
  font-size: 12.5px;
  color: var(--text-mute);
  display: inline-flex;
  align-items: center;
}
.scenario-keys span + span::before {
  content: "·";
  margin-right: 8px;
  color: var(--text-faint);
}
.scenario-arrow {
  color: var(--text-mute);
  font-size: 18px;
  transition: all 0.15s ease;
}
.scenario-card:hover .scenario-arrow {
  color: var(--primary);
  transform: translateX(2px);
}

/* ---- CTA ---- */
.cta {
  text-align: center;
  padding: 100px 0;
  background: var(--bg-soft);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}
.cta h2 {
  font-size: clamp(28px, 3.5vw, 40px);
  margin-bottom: 16px;
  letter-spacing: -0.02em;
}
.cta p {
  font-size: 17px;
  color: var(--text-mid);
  margin-bottom: 36px;
  max-width: 56ch;
  margin-left: auto;
  margin-right: auto;
}
.cta-actions {
  display: flex;
  gap: 12px;
  justify-content: center;
  flex-wrap: wrap;
}

/* ---- 页脚 ---- */
.footer {
  background: var(--bg);
  padding: 64px 0 32px;
  border-top: 1px solid var(--line);
  font-size: 14px;
  color: var(--text-mid);
}
.footer-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 56px;
  margin-bottom: 56px;
}
.footer-brand { flex: 2 1 320px; min-width: 240px; }
.footer-brand .brand { margin-bottom: 20px; }
.footer-brand p {
  color: var(--text-mid);
  max-width: 38ch;
  line-height: 1.7;
  font-size: 14px;
}
.footer-col { flex: 1 1 160px; min-width: 140px; }
.footer-col h4 {
  font-size: 13px;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 16px;
}
.footer-col ul { list-style: none; }
.footer-col li { margin-bottom: 10px; }
.footer-col a {
  color: var(--text-mid);
  font-size: 14px;
}
.footer-col a:hover { color: var(--text); }

.footer-contact { font-size: 14px; }
.footer-contact div { margin-bottom: 8px; color: var(--text-mid); }
.footer-contact .v { color: var(--text); }

.footer-bottom {
  padding-top: 24px;
  border-top: 1px solid var(--line);
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
  font-size: 13px;
  color: var(--text-mute);
}
.footer-bottom a { color: var(--text-mute); }
.footer-bottom a:hover { color: var(--text-mid); }
.footer-icp { display: flex; gap: 20px; flex-wrap: wrap; }

/* ---- 二级页头 ---- */
.page-header {
  padding: 80px 0 64px;
  border-bottom: 1px solid var(--line);
  background: var(--bg);
}
.breadcrumb {
  font-size: 13px;
  color: var(--text-mute);
  margin-bottom: 28px;
}
.breadcrumb a { color: var(--text-mute); }
.breadcrumb a:hover { color: var(--text); }
.breadcrumb .sep { margin: 0 8px; color: var(--text-faint); }
.breadcrumb .current { color: var(--text); }
.page-header .eyebrow {
  font-size: 13px;
  font-weight: 500;
  color: var(--primary);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 16px;
  display: block;
}
.page-header h1 {
  font-size: clamp(36px, 5vw, 56px);
  line-height: 1.1;
  letter-spacing: -0.025em;
  margin-bottom: 20px;
  max-width: 20ch;
}
.page-header .page-desc {
  color: var(--text-mid);
  font-size: 18px;
  max-width: 60ch;
  line-height: 1.6;
}

/* ---- 规格指标 ---- */
.spec-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 0;
  border: 1px solid var(--line);
  border-radius: 12px;
  overflow: hidden;
  background: var(--bg);
}
.spec-item {
  flex: 1 1 240px;
  min-width: 220px;
  padding: 32px;
  border-right: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}
.spec-key {
  font-size: 13px;
  color: var(--text-mute);
  margin-bottom: 12px;
  font-weight: 500;
}
.spec-value {
  font-size: 36px;
  font-weight: 700;
  color: var(--text);
  letter-spacing: -0.02em;
  line-height: 1;
  margin-bottom: 10px;
  font-variant-numeric: tabular-nums;
}
.spec-value .unit {
  font-size: 16px;
  color: var(--text-mute);
  font-weight: 400;
  margin-left: 4px;
}
.spec-desc {
  color: var(--text-mid);
  font-size: 13.5px;
  line-height: 1.5;
}

/* ---- 模块详解 ---- */
.module {
  display: flex;
  flex-wrap: wrap;
  gap: 64px;
  margin-bottom: 96px;
  align-items: center;
}
.module:last-child { margin-bottom: 0; }
.module > * { flex: 1 1 380px; min-width: 0; }
.module.reverse { flex-direction: row-reverse; }
.module-info .eyebrow {
  font-size: 12px;
  font-weight: 500;
  color: var(--primary);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 14px;
  display: block;
}
.module-info h2 {
  font-size: clamp(26px, 3vw, 34px);
  line-height: 1.2;
  margin-bottom: 18px;
  letter-spacing: -0.02em;
}
.module-info p {
  color: var(--text-mid);
  font-size: 16px;
  line-height: 1.7;
  margin-bottom: 20px;
}
.module-info ul { list-style: none; margin: 20px 0; }
.module-info ul li {
  padding: 10px 0;
  padding-left: 26px;
  position: relative;
  font-size: 15px;
  color: var(--text);
  line-height: 1.65;
}
.module-info ul li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 18px;
  width: 14px;
  height: 2px;
  background: var(--primary);
}

.module-visual {
  background: var(--bg-soft);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 28px;
}
.flow-step {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 14px 18px;
  background: var(--bg);
  border: 1px solid var(--line);
  border-radius: 8px;
  margin-bottom: 8px;
  font-size: 14.5px;
  color: var(--text);
}
.flow-step:last-child { margin-bottom: 0; }
.flow-step .step-tag {
  font-size: 11px;
  font-weight: 600;
  color: var(--primary);
  letter-spacing: 0.05em;
  min-width: 44px;
}

/* ---- 关于页 ---- */
.about-layout { display: flex; flex-wrap: wrap; gap: 64px; }
.about-main { flex: 2 1 500px; min-width: 0; }
.about-side { flex: 1 1 280px; min-width: 240px; }
.about-main h2 {
  font-size: clamp(24px, 2.5vw, 30px);
  margin: 48px 0 16px;
  letter-spacing: -0.01em;
}
.about-main h2:first-of-type { margin-top: 0; }
.about-main p {
  color: var(--text);
  font-size: 16px;
  line-height: 1.8;
  margin-bottom: 16px;
}
.about-main blockquote {
  border-left: 3px solid var(--primary);
  padding: 12px 24px;
  margin: 32px 0;
  font-size: 17px;
  color: var(--text-mid);
  line-height: 1.7;
}
.about-main blockquote em {
  font-style: normal;
  color: var(--text);
  font-weight: 500;
}

.info-card {
  background: var(--bg-soft);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 28px;
  margin-bottom: 16px;
}
.info-card h4 {
  font-size: 13px;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 18px;
}
.info-list { list-style: none; }
.info-list li {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  padding: 10px 0;
  border-bottom: 1px solid var(--line);
  font-size: 14px;
}
.info-list li:last-child { border-bottom: none; }
.info-list .k { color: var(--text-mute); }
.info-list .v {
  color: var(--text);
  font-weight: 500;
  font-variant-numeric: tabular-nums;
}
.info-card .quote-cn {
  font-size: 17px;
  font-weight: 500;
  color: var(--text);
  line-height: 1.7;
  margin-bottom: 6px;
}
.info-card .quote-en {
  font-size: 12px;
  color: var(--text-mute);
}
.info-card .product-name {
  font-size: 22px;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 4px;
  letter-spacing: -0.01em;
}
.info-card .product-sub {
  font-size: 13.5px;
  color: var(--text-mute);
}

/* ---- 联系页 ---- */
.contact-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 20px;
  margin-bottom: 80px;
}
.contact-item {
  flex: 1 1 260px;
  min-width: 240px;
  padding: 32px;
  background: var(--bg);
  border: 1px solid var(--line);
  border-radius: 12px;
}
.contact-item .ct-label {
  font-size: 13px;
  color: var(--text-mute);
  margin-bottom: 12px;
  font-weight: 500;
}
.contact-item .ct-value {
  font-size: 20px;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 10px;
  letter-spacing: -0.01em;
  font-variant-numeric: tabular-nums;
}
.contact-item .ct-sub {
  color: var(--text-mid);
  font-size: 13.5px;
  line-height: 1.5;
}

.services-grid { display: flex; flex-wrap: wrap; gap: 24px; }
.service-item {
  flex: 1 1 280px;
  min-width: 240px;
  padding: 28px;
  background: var(--bg-soft);
  border: 1px solid var(--line);
  border-radius: 12px;
}
.service-icon {
  width: 36px; height: 36px;
  border-radius: 8px;
  background: var(--primary-soft);
  color: var(--primary);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 16px;
}
.service-icon svg { width: 18px; height: 18px; }
.service-item h3 {
  font-size: 16px;
  margin-bottom: 8px;
  font-weight: 600;
}
.service-item p {
  color: var(--text-mid);
  font-size: 14px;
  line-height: 1.6;
}

/* ---- 响应式 ---- */
@media (max-width: 768px) {
  .container { padding: 0 20px; }
  .nav-inner { padding: 0 20px; }
  .nav-links { display: none; }
  .nav-toggle { display: inline-flex; }
  .nav-phone { display: none; }
  .section { padding: 64px 0; }
  .hero { padding: 48px 0; }
  .hero-inner, .hero-facts { padding: 0 20px; }
  .hero-facts { gap: 24px 40px; padding-top: 32px; }
  .hero-actions .btn { flex: 1; justify-content: center; }
  .section-head { margin-bottom: 40px; }
  .arch-row, .module { gap: 40px; }
  .module.reverse { flex-direction: column; }
  .footer-grid { gap: 40px; }
  .footer-bottom { flex-direction: column; }
  .spec-item { border-right: none; }
}

.nav-links.open {
  display: flex;
  flex-direction: column;
  position: absolute;
  top: 64px;
  left: 0;
  right: 0;
  background: var(--bg);
  border-bottom: 1px solid var(--line);
  padding: 16px;
  gap: 4px;
}
.nav-links.open li { width: 100%; }
.nav-links.open a { display: block; padding: 12px 16px; }

/* ============================================================
   图片样式
   ============================================================ */
.brand-logo {
  width: 28px;
  height: 28px;
  object-fit: contain;
  flex-shrink: 0;
  display: block;
}

/* 通用图片包装(占位 + fallback)*/
.media {
  display: block;
  width: 100%;
  background: var(--bg-soft);
  border-radius: 12px;
  overflow: hidden;
  position: relative;
  border: 1px solid var(--line);
}
.media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
  transition: opacity 0.2s ease;
}
[data-theme="dark"] .media img {
  filter: brightness(0.92);
}

/* 比例容器 — 16:10 用于场景卡 */
.media-16-10 { aspect-ratio: 16 / 10; }
.media-16-9  { aspect-ratio: 16 / 9; }
.media-4-3   { aspect-ratio: 4 / 3; }
.media-3-2   { aspect-ratio: 3 / 2; }

/* 没有 aspect-ratio 支持时的兜底 */
@supports not (aspect-ratio: 1) {
  .media-16-10::before { content: ""; display: block; padding-top: 62.5%; }
  .media-16-9::before  { content: ""; display: block; padding-top: 56.25%; }
  .media-4-3::before   { content: ""; display: block; padding-top: 75%; }
  .media-3-2::before   { content: ""; display: block; padding-top: 66.67%; }
  .media img { position: absolute; top: 0; left: 0; }
}

/* Hero 新版双栏布局 */
.hero-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 56px;
  align-items: center;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 32px;
}
.hero-grid .hero-text {
  flex: 1 1 460px;
  min-width: 0;
}
.hero-grid .hero-media {
  flex: 1 1 460px;
  min-width: 0;
}
.hero-grid .hero-eyebrow { margin-bottom: 24px; }

/* 场景卡顶部图 */
.scenario-card .scene-media {
  margin: -36px -32px 24px;
  border-radius: 0;
  border-left: none;
  border-right: none;
  border-top: none;
  border-bottom: 1px solid var(--line);
}
.scenario-card .scene-media img {
  transition: transform 0.4s ease;
}
.scenario-card:hover .scene-media img {
  transform: scale(1.03);
}

/* 模块详解的图(替换原 module-visual 流程框)*/
.module-visual.media {
  padding: 0;
  background: var(--bg-soft);
  border: 1px solid var(--line);
}

/* 产品页 header 大图 */
.product-hero-media {
  margin-top: 40px;
  border-radius: 12px;
  overflow: hidden;
  border: 1px solid var(--line);
}

/* 架构页大图 */
.arch-full-media {
  margin: 48px auto 0;
  max-width: 100%;
  background: var(--bg-soft);
  border: 1px solid var(--line);
  border-radius: 12px;
  overflow: hidden;
}

/* About 页面图 */
.about-media {
  margin-bottom: 48px;
  border-radius: 12px;
  overflow: hidden;
  border: 1px solid var(--line);
}

/* Contact 页地图 */
.contact-media {
  margin-bottom: 80px;
  border-radius: 12px;
  overflow: hidden;
  border: 1px solid var(--line);
  background: var(--bg-soft);
}

/* 产品页 header logo + 标题排版 */
.product-header-row {
  display: flex;
  align-items: center;
  gap: 32px;
}

/* 首页 Hero 区:产品 logo + 名称组合 */
.hero-product-brand {
  display: inline-flex;
  align-items: center;
  gap: 16px;
  margin-bottom: 24px;
}
.hero-product-logo {
  flex-shrink: 0;
  width: 56px;
  height: 56px;
  border-radius: 12px;
  background: linear-gradient(135deg, #EDF2FB 0%, #DCE7F5 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 6px;
  box-shadow:
    0 1px 2px rgba(20, 30, 50, 0.04),
    0 4px 12px rgba(30, 91, 184, 0.08);
  border: 1px solid rgba(30, 91, 184, 0.08);
  box-sizing: border-box;
}
[data-theme="dark"] .hero-product-logo {
  background: linear-gradient(135deg, #1A2438 0%, #243352 100%);
  box-shadow:
    0 1px 2px rgba(0, 0, 0, 0.3),
    0 4px 12px rgba(91, 142, 232, 0.15);
  border: 1px solid rgba(91, 142, 232, 0.15);
}
.hero-product-logo img {
  width: 100%;
  height: 100%;
  object-fit: contain;
  display: block;
}
.hero-product-name {
  display: flex;
  flex-direction: column;
  gap: 2px;
  line-height: 1.2;
}
.hero-product-name .name {
  font-size: 18px;
  font-weight: 700;
  color: var(--text);
  letter-spacing: -0.01em;
}
.hero-product-name .tagline {
  font-size: 13px;
  color: var(--text-mute);
  font-weight: 500;
}

.product-logo {
  flex-shrink: 0;
  width: 180px;
  height: 180px;
  border-radius: 20px;
  background: linear-gradient(135deg, #EDF2FB 0%, #DCE7F5 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 14px;
  box-shadow:
    0 1px 2px rgba(20, 30, 50, 0.04),
    0 8px 24px rgba(30, 91, 184, 0.08);
  border: 1px solid rgba(30, 91, 184, 0.08);
  box-sizing: border-box;
}
[data-theme="dark"] .product-logo {
  background: linear-gradient(135deg, #1A2438 0%, #243352 100%);
  box-shadow:
    0 1px 2px rgba(0, 0, 0, 0.3),
    0 8px 24px rgba(91, 142, 232, 0.15);
  border: 1px solid rgba(91, 142, 232, 0.15);
}
.product-logo img {
  width: 100%;
  height: 100%;
  object-fit: contain;
  display: block;
  margin: 0;
}
.product-header-content {
  flex: 1;
  min-width: 0;
}
.product-header-content .eyebrow { margin-bottom: 12px; }
.product-header-content h1 { margin-top: 0; }

@media (max-width: 640px) {
  .product-header-row {
    flex-direction: column;
    gap: 20px;
    align-items: flex-start;
  }
  .product-logo {
    width: 96px;
    height: 96px;
    border-radius: 16px;
    padding: 10px;
  }
}

/* 暗色模式下 logo 反相处理 — 如果用户上传深色 logo 在白底上可读,
   暗色背景下读不清,可以通过 CSS 反相;但更好的方案是用户传 logo-dark.png。
   这里不做强制反相,保持原图 */