/* ============================================================
   备案静态页【大数据智能分析】 样式
   设计风格：深色科技感，参考阿里云大数据 / 腾讯云大数据 / Databricks
   兼容性：纯 CSS3，无 webfont 外链，无外部依赖（备案巡检最优解）
   ============================================================ */

/* 重置 */
* { margin: 0; padding: 0; box-sizing: border-box; }
html, body {
  height: 100%;
  font-family: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  font-size: 15px;
  line-height: 1.6;
  color: #d8def0;
  background: #0a0e1a;
  -webkit-font-smoothing: antialiased;
}
a { color: inherit; text-decoration: none; }
a:hover { color: #5eead4; }
img { vertical-align: middle; }

/* ───── 顶部导航栏 ───── */
.topbar {
  position: sticky; top: 0; z-index: 100;
  backdrop-filter: blur(10px);
  background: rgba(10, 14, 26, 0.78);
  border-bottom: 1px solid rgba(99, 102, 241, 0.12);
}
.topbar-inner {
  max-width: 1200px; margin: 0 auto;
  height: 64px; padding: 0 28px;
  display: flex; align-items: center; justify-content: space-between;
}
.brand { display: flex; align-items: center; gap: 10px; }
.brand-logo { display: inline-flex; }
.brand-name {
  font-size: 18px; font-weight: 600; letter-spacing: 0.5px;
  background: linear-gradient(90deg, #5eead4 0%, #6366f1 60%, #c084fc 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.topnav { display: flex; gap: 28px; }
.topnav a {
  font-size: 14px; color: #a1a8c0;
  transition: color .2s ease;
}
.topnav a:hover { color: #fff; }

/* ───── 主视觉区 ───── */
.hero {
  position: relative;
  padding: 84px 28px 64px;
  text-align: center;
  overflow: hidden;
}
.hero-bg {
  position: absolute; inset: 0;
  background:
    radial-gradient(circle at 20% 30%, rgba(99, 102, 241, 0.18) 0%, transparent 45%),
    radial-gradient(circle at 80% 60%, rgba(94, 234, 212, 0.14) 0%, transparent 45%),
    radial-gradient(circle at 50% 90%, rgba(192, 132, 252, 0.10) 0%, transparent 50%);
  pointer-events: none;
}
.hero-bg::after {
  /* 网格点阵覆盖层，营造大数据感 */
  content: '';
  position: absolute; inset: 0;
  background-image: radial-gradient(rgba(99, 102, 241, 0.08) 1px, transparent 1px);
  background-size: 28px 28px;
  mask-image: radial-gradient(circle at 50% 40%, #000 0%, transparent 70%);
  -webkit-mask-image: radial-gradient(circle at 50% 40%, #000 0%, transparent 70%);
}
.hero-inner {
  position: relative; z-index: 1;
  max-width: 1100px; margin: 0 auto;
}
.badge {
  display: inline-block;
  padding: 6px 18px;
  font-size: 12px; letter-spacing: 3px;
  color: #8b9bd1;
  background: rgba(99, 102, 241, 0.10);
  border: 1px solid rgba(99, 102, 241, 0.30);
  border-radius: 24px;
  margin-bottom: 28px;
}
.hero-title {
  font-size: 56px; line-height: 1.18;
  font-weight: 700; letter-spacing: 1px;
  margin-bottom: 24px;
  background: linear-gradient(120deg, #ffffff 0%, #c5d1ff 50%, #5eead4 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.hero-sub {
  font-size: 26px; font-weight: 400;
  color: #a8b3d8;
  -webkit-text-fill-color: #a8b3d8;
}
.hero-desc {
  font-size: 16px; color: #a1a8c0;
  max-width: 720px; margin: 0 auto 36px;
}

/* 开发中提示卡片：用户明确要求 */
.building-card {
  display: inline-flex; align-items: center; gap: 14px;
  padding: 14px 24px;
  background: linear-gradient(135deg, rgba(94, 234, 212, 0.10), rgba(99, 102, 241, 0.10));
  border: 1px solid rgba(94, 234, 212, 0.35);
  border-radius: 12px;
  margin-bottom: 56px;
  text-align: left;
}
.building-icon {
  color: #5eead4;
  display: inline-flex; align-items: center;
  animation: spin 6s linear infinite;
}
@keyframes spin {
  from { transform: rotate(0deg); }
  to   { transform: rotate(360deg); }
}
.building-text strong {
  display: block; font-size: 16px; color: #5eead4;
  margin-bottom: 2px;
}
.building-text span {
  display: block; font-size: 13px; color: #8b9bd1;
}

/* 主视觉数据区 */
.hero-stats {
  display: flex; justify-content: center; gap: 60px;
  flex-wrap: wrap;
}
.stat { text-align: center; }
.stat-num {
  font-size: 36px; font-weight: 700;
  background: linear-gradient(120deg, #5eead4, #6366f1);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  font-feature-settings: "tnum"; /* 等宽数字 */
}
.stat-label {
  font-size: 13px; color: #8b9bd1;
  margin-top: 4px; letter-spacing: 1px;
}

/* ───── 通用 section ───── */
.section {
  padding: 80px 28px;
  border-top: 1px solid rgba(99, 102, 241, 0.06);
}
.section-alt { background: rgba(99, 102, 241, 0.025); }
.section-inner {
  max-width: 1200px; margin: 0 auto;
}
.section-title {
  font-size: 32px; font-weight: 700;
  color: #f0f3ff;
  text-align: center;
  margin-bottom: 12px;
}
.section-desc {
  font-size: 15px; color: #8b9bd1;
  text-align: center; margin-bottom: 48px;
}

/* ───── 4 列卡片 ───── */
.grid-4 {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 24px;
}
.card {
  padding: 32px 24px;
  background: rgba(99, 102, 241, 0.04);
  border: 1px solid rgba(99, 102, 241, 0.12);
  border-radius: 12px;
  transition: all .25s ease;
}
.card:hover {
  border-color: rgba(94, 234, 212, 0.45);
  background: rgba(94, 234, 212, 0.04);
  transform: translateY(-4px);
}
.card h3 {
  font-size: 17px; color: #f0f3ff;
  margin-bottom: 10px;
}
.card p {
  font-size: 14px; color: #a1a8c0;
}
.card-icon {
  width: 44px; height: 44px;
  border-radius: 10px;
  margin-bottom: 18px;
  background: linear-gradient(135deg, rgba(99, 102, 241, 0.20), rgba(94, 234, 212, 0.20));
  display: flex; align-items: center; justify-content: center;
}
.card-icon::before {
  font-size: 22px; line-height: 1;
}
.i-collect::before { content: "\2630"; color: #5eead4; }   /* ☰ */
.i-clean::before   { content: "\26A1"; color: #fbbf24; }   /* ⚡ */
.i-model::before   { content: "\2206"; color: #c084fc; }   /* ∆ */
.i-visual::before  { content: "\2316"; color: #6366f1; }   /* ⌖ */

/* ───── 3 列场景卡片 ───── */
.grid-3 {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 24px;
}
.scene-card {
  padding: 28px 24px;
  background: linear-gradient(135deg, rgba(99, 102, 241, 0.08), rgba(94, 234, 212, 0.04));
  border: 1px solid rgba(99, 102, 241, 0.15);
  border-radius: 12px;
}
.scene-card h3 {
  font-size: 18px; color: #f0f3ff; margin-bottom: 10px;
}
.scene-card p { font-size: 14px; color: #a1a8c0; }

/* ───── 技术体系 chips ───── */
.stack-row {
  display: flex; flex-wrap: wrap; justify-content: center; gap: 12px;
}
.chip {
  padding: 8px 18px;
  font-size: 13px;
  background: rgba(99, 102, 241, 0.08);
  border: 1px solid rgba(99, 102, 241, 0.25);
  border-radius: 999px;
  color: #c5d1ff;
}

/* ───── 关于我们 ───── */
.about-inner { max-width: 880px; margin: 0 auto; text-align: center; }
.about-text {
  font-size: 15px; color: #a8b3d8;
  margin: 0 auto 16px; max-width: 760px;
}
.about-text.muted { color: #6b7299; font-size: 14px; }

/* ───── 底部备案 ───── */
.footer {
  padding: 24px 28px;
  background: #060914;
  border-top: 1px solid rgba(99, 102, 241, 0.08);
}
.footer-inner {
  max-width: 1200px; margin: 0 auto;
  text-align: center;
  font-size: 12px; color: #6b7299;
  display: flex; flex-wrap: wrap; justify-content: center; align-items: center;
  gap: 8px;
}
.footer-inner a {
  color: #8b9bd1;
  display: inline-flex; align-items: center; gap: 4px;
  transition: color .2s ease;
}
.footer-inner a:hover { color: #5eead4; }
.footer-sep { color: #2c3450; }
.mps-icon { width: 14px; height: 14px; vertical-align: -2px; }

/* ───── 响应式 ───── */
@media (max-width: 768px) {
  .hero { padding: 56px 20px 40px; }
  .hero-title { font-size: 36px; }
  .hero-sub { font-size: 18px; }
  .hero-stats { gap: 36px; }
  .stat-num { font-size: 28px; }
  .topnav { display: none; }
  .section { padding: 56px 20px; }
  .section-title { font-size: 24px; }
}