/* ===== 四个核心服务页共享基础（主色一致，风格各异） ===== */
:root {
  --blue: #2563eb;
  --blue-700: #1d4ed8;
  --blue-950: #142554;
  --cyan: #0891b2;
  --green: #16a34a;
  --amber: #f59e0b;
  --gold: #fbbf24;
  --purple: #7c3aed;
  --teal: #0d9488;
  --red: #dc2626;
  --ink: #0f172a;
  --text: #334155;
  --muted: #64748b;
  --line: #dbe7fb;
  --surface: #ffffff;
  --soft: #f4f8ff;
  --soft-blue: #eaf3ff;
  --dark: #0a1733;
  --dark-2: #122244;
  --radius: 8px;
  --shadow: 0 22px 60px rgba(30, 64, 175, 0.12);
  --shadow-card: 0 12px 36px rgba(30, 64, 175, 0.06);
}

* { box-sizing: border-box; }
body {
  margin: 0;
  color: var(--ink);
  font-family: "PingFang SC", "Microsoft YaHei", "Noto Sans SC", Inter, Arial, sans-serif;
  line-height: 1.7;
}
a { color: inherit; text-decoration: none; }
.container { width: min(1180px, calc(100% - 64px)); margin: 0 auto; }

/* 跑马灯 + 导航 + 页脚（与其他页一致） */
.topline {
  height: 34px; background: #1459d9; color: #eaf3ff; font-size: 13px;
  display: flex; align-items: center; overflow: hidden; position: relative; white-space: nowrap;
}
.topline-track {
  display: inline-flex; align-items: center; white-space: nowrap;
  position: absolute; left: 0; animation: topline-pingpong 38s ease-in-out infinite;
}
.topline-track span { opacity: 0.92; display: inline-flex; align-items: center; }
.topline-track span::after { content: "\00a0\00a0\00a0"; opacity: 0.5; }
.topline-track span:last-child::after { content: ""; }
.topline:hover .topline-track { animation-play-state: paused; }
@keyframes topline-pingpong {
  0% { left: 0; }
  45% { left: calc(100% - var(--track-w, 400px)); }
  55% { left: calc(100% - var(--track-w, 400px)); }
  100% { left: 0; }
}
      .nav {
        height: 76px;
        background: rgba(255, 255, 255, 0.78);
        backdrop-filter: blur(20px) saturate(180%);
        -webkit-backdrop-filter: blur(20px) saturate(180%);
        border-bottom: 1px solid rgba(219, 231, 251, 0.7);
        position: sticky; top: 0; z-index: 20;
        box-shadow: 0 1px 0 rgba(15, 23, 42, 0.02);
      }
      .nav-inner {
        height: 76px;
        display: flex; align-items: center; justify-content: space-between;
        gap: 24px;
      }
      .brand { display: flex; align-items: center; gap: 12px; flex-shrink: 0; }
      .brand-logo {
        width: 44px; height: 44px; border-radius: 50%;
        background: linear-gradient(135deg, #1d4ed8, #0891b2);
        display: grid; place-items: center;
        color: #fff; font-weight: 800; font-size: 20px;
        box-shadow: 0 6px 16px rgba(37, 99, 235, 0.28);
        flex: 0 0 auto;
      }
      .brand-name { font-weight: 800; font-size: 21px; line-height: 1.05; display: block; }
      .brand-sub { color: var(--muted); font-size: 12px; margin-top: 4px; display: block; }
      .nav-links {
        display: flex; align-items: center; gap: 4px;
        background: rgba(241, 245, 249, 0.7);
        border: 1px solid rgba(226, 232, 240, 0.8);
        padding: 5px;
        border-radius: 999px;
        color: #475569; font-size: 14px; font-weight: 600;
        flex: 1; justify-content: center; max-width: 760px;
        margin: 0 auto;
      }
      .nav-links a {
        position: relative;
        display: inline-flex; align-items: center;
        padding: 8px 16px; border-radius: 999px;
        color: #475569; text-decoration: none; white-space: nowrap;
        line-height: 1.2;
        transition: color 0.2s, background 0.2s;
      }
      .nav-links a:hover {
        color: #1d4ed8; background: rgba(37, 99, 235, 0.06);
      }
      .nav-links a.active {
        color: #fff;
        background: linear-gradient(135deg, #1d4ed8 0%, #2563eb 100%);
        box-shadow: 0 4px 12px rgba(37, 99, 235, 0.28);
      }
      .nav-links a.active:hover {
        color: #fff; background: linear-gradient(135deg, #1d4ed8 0%, #2563eb 100%);
      }
      .nav-actions { display: flex; align-items: center; gap: 10px; flex-shrink: 0; }
.btn {
  min-height: 44px; padding: 0 22px; border-radius: 999px;
  display: inline-flex; align-items: center; justify-content: center;
  font-weight: 700; font-size: 14px; border: 1px solid transparent; cursor: pointer; white-space: nowrap;
  transition: transform 0.2s, box-shadow 0.2s;
}
.btn-primary { color: #fff; background: var(--blue); box-shadow: 0 12px 28px rgba(37,99,235,0.26); }
.btn-secondary { color: var(--blue-700); background: #fff; border-color: #bfd6ff; }
.btn-gold { color: var(--dark); background: var(--gold); box-shadow: 0 12px 28px rgba(251,191,36,0.3); }
.btn-outline { color: #dbeafe; background: transparent; border-color: rgba(219,234,254,0.4); }
.btn:hover { transform: translateY(-2px); }

.breadcrumb { padding: 18px 0 0; font-size: 13px; color: var(--muted); }
.breadcrumb a:hover { color: var(--blue); }
.breadcrumb .sep { margin: 0 8px; opacity: 0.5; }
.breadcrumb .current { color: var(--ink); font-weight: 600; }

.footer { background: #0d2a5f; color: #dbeafe; padding: 34px 0; }
.footer-inner { display: flex; align-items: center; justify-content: space-between; gap: 30px; }
.footer .brand-name { color: #fff; }
.footer .brand-sub { color: #bfdbfe; }
.footer-links { display: flex; gap: 22px; font-size: 13px; color: #bfdbfe; }
.footer-links a:hover { color: #fff; }

/* 通用 section */
section { padding: 72px 0; }
.section-head-center { text-align: center; margin-bottom: 40px; }
.section-head-center .kicker { color: var(--blue); font-weight: 800; font-size: 13px; margin-bottom: 10px; letter-spacing: 1px; }
.section-head-center .kicker.light { color: var(--gold); }
.section-head-center h2 { font-size: 34px; margin: 0 0 12px; line-height: 1.2; }
.section-head-center h2.light { color: #fff; }
.section-head-center .section-desc { color: var(--muted); font-size: 15px; max-width: 560px; margin: 0 auto; }

/* 科技感网格背景（通用） */
.tech-grid-bg {
  position: relative; overflow: hidden;
}
.tech-grid-bg::before {
  content: ""; position: absolute; inset: 0;
  background-image:
    linear-gradient(rgba(37,99,235,0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(37,99,235,0.05) 1px, transparent 1px);
  background-size: 40px 40px;
  mask-image: radial-gradient(ellipse at center, #000 0%, transparent 70%);
  pointer-events: none;
}

/* AI 粒子装饰（通用） */
.ai-particles {
  position: absolute; top: 0; right: 0; width: 300px; height: 300px;
  pointer-events: none; opacity: 0.5;
}
.ai-particles::before, .ai-particles::after {
  content: ""; position: absolute; border-radius: 50%;
}
.ai-particles::before {
  width: 200px; height: 200px; top: 20px; right: 20px;
  background: radial-gradient(circle, var(--accent-glow, rgba(37,99,235,0.2)), transparent 65%);
  animation: pulse 4s ease-in-out infinite;
}
.ai-particles::after {
  width: 120px; height: 120px; top: 80px; right: 80px;
  background: radial-gradient(circle, var(--accent-glow2, rgba(8,145,178,0.15)), transparent 65%);
  animation: pulse 4s ease-in-out infinite 2s;
}
@keyframes pulse {
  0%, 100% { transform: scale(1); opacity: 0.5; }
  50% { transform: scale(1.2); opacity: 0.8; }
}

/* 响应式 */
@media (max-width: 900px) {
  .container { width: min(100% - 32px, 1180px); }
  .nav-links { display: none; }
  .footer-inner { flex-direction: column; align-items: flex-start; }
}