/* ============ 基础变量（老徐：改这里即可换主题色） ============ */
:root {
  --bg: #0a0e1a;
  --bg-alt: #0f1525;
  --surface: #131a2e;
  --surface-2: #1a2440;
  --primary: #00d4ff;      /* 科技青蓝 */
  --accent: #7b61ff;       /* 赛博紫 */
  --text: #e8ecf4;
  --text-dim: #9aa6c0;
  --border: rgba(255, 255, 255, 0.08);
  --radius: 16px;
  --maxw: 1120px;
  --shadow: 0 10px 40px rgba(0, 0, 0, 0.45);
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html { scroll-behavior: smooth; scroll-padding-top: 72px; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Microsoft YaHei", "Hiragino Sans GB", sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

a { color: inherit; text-decoration: none; }

.container { width: 100%; max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }

/* ============ 顶部导航 ============ */
.site-header {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  background: rgba(10, 14, 26, 0.72);
  backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--border);
  transition: box-shadow .3s ease;
}
.nav-inner { display: flex; align-items: center; justify-content: space-between; height: 64px; }
.brand { display: flex; align-items: center; gap: 10px; font-weight: 700; }
.brand-mark {
  width: 34px; height: 34px; display: grid; place-items: center;
  border-radius: 9px; font-size: 18px; color: #04121a; font-weight: 800;
  background: linear-gradient(135deg, var(--primary), var(--accent));
}
.brand-text { letter-spacing: .5px; }
.nav-links { display: flex; gap: 28px; }
.nav-links a { color: var(--text-dim); font-size: 15px; transition: color .2s; }
.nav-links a:hover { color: var(--primary); }
.nav-toggle { display: none; flex-direction: column; gap: 5px; background: none; border: 0; cursor: pointer; padding: 8px; }
.nav-toggle span { width: 24px; height: 2px; background: var(--text); border-radius: 2px; transition: .3s; }

/* ============ Hero ============ */
.hero { position: relative; padding: 160px 0 100px; text-align: center; overflow: hidden; }
.hero-inner { position: relative; z-index: 2; }
.eyebrow {
  display: inline-block; color: var(--primary); font-size: 14px; letter-spacing: 3px;
  text-transform: uppercase; margin-bottom: 18px; padding: 6px 14px;
  border: 1px solid var(--border); border-radius: 999px; background: rgba(0, 212, 255, 0.06);
}
.hero h1 { font-size: clamp(34px, 6vw, 60px); line-height: 1.15; font-weight: 800; }
.grad {
  background: linear-gradient(120deg, var(--primary), var(--accent));
  -webkit-background-clip: text; background-clip: text; color: transparent;
}
.lead { max-width: 680px; margin: 22px auto 34px; color: var(--text-dim); font-size: 18px; }
.hero-cta { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; }
.btn { display: inline-block; padding: 13px 28px; border-radius: 999px; font-weight: 600; transition: transform .2s, box-shadow .2s; }
.btn-primary { background: linear-gradient(135deg, var(--primary), var(--accent)); color: #04121a; }
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 12px 30px rgba(0, 212, 255, 0.3); }
.btn-ghost { border: 1px solid var(--border); color: var(--text); }
.btn-ghost:hover { border-color: var(--primary); color: var(--primary); }
.hero-stats { list-style: none; display: flex; gap: 48px; justify-content: center; margin-top: 56px; flex-wrap: wrap; }
.hero-stats li { display: flex; flex-direction: column; }
.hero-stats strong { font-size: 30px; background: linear-gradient(120deg, var(--primary), var(--accent)); -webkit-background-clip: text; background-clip: text; color: transparent; }
.hero-stats span { color: var(--text-dim); font-size: 13px; }
.hero-glow {
  position: absolute; top: -10%; left: 50%; transform: translateX(-50%);
  width: 900px; height: 600px; z-index: 1; pointer-events: none;
  background: radial-gradient(circle, rgba(0, 212, 255, 0.18), transparent 60%);
  filter: blur(20px);
}

/* ============ 通用 section ============ */
.section { padding: 88px 0; }
.section-alt { background: var(--bg-alt); }
.section-title { font-size: clamp(26px, 4vw, 38px); font-weight: 800; text-align: center; margin-bottom: 12px; }
.section-sub { text-align: center; color: var(--text-dim); margin-bottom: 48px; }
.prose { max-width: 820px; margin: 0 auto 18px; color: var(--text-dim); font-size: 17px; }

/* ============ 卡片网格 ============ */
.card-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 22px; }
.card {
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 28px; transition: transform .25s, border-color .25s;
}
.card:hover { transform: translateY(-6px); border-color: rgba(0, 212, 255, 0.4); }
.card-icon { font-size: 30px; margin-bottom: 14px; }
.card h3 { font-size: 19px; margin-bottom: 10px; }
.card p { color: var(--text-dim); font-size: 15px; }
/* ============ 核心业务：大类容器 + 子产品网格（数量不限，可无限扩展） ============ */
.biz-category { margin-bottom: 44px; }
.biz-category:last-child { margin-bottom: 0; }
.biz-cat-head { display: flex; align-items: flex-start; gap: 16px; margin-bottom: 20px; }
.biz-cat-icon { font-size: 34px; line-height: 1; flex: none; }
.biz-cat-title { font-size: 22px; margin-bottom: 4px; }
.biz-cat-desc { color: var(--text-dim); font-size: 15px; max-width: 760px; }
.subproduct-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(230px, 1fr)); gap: 16px; }
.subproduct {
  display: block; text-decoration: none; color: inherit; cursor: pointer;
  background: var(--surface); border: 1px solid var(--border); border-radius: 12px;
  padding: 20px; transition: transform .25s, border-color .25s;
}
.subproduct:hover { transform: translateY(-4px); border-color: rgba(0, 212, 255, 0.4); }
.subproduct h4 { font-size: 16px; margin-bottom: 8px; color: var(--primary); }
.subproduct p { color: var(--text-dim); font-size: 14px; line-height: 1.65; }

/* ============ 三档产品定价（首页/产品页通用） ============ */
.pricing-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 20px; }
.pricing-card {
  position: relative; display: flex; flex-direction: column;
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 28px 26px; transition: transform .25s, border-color .25s;
}
.pricing-card:hover { transform: translateY(-6px); border-color: rgba(0, 212, 255, 0.4); }
.pricing-card.featured {
  border-color: rgba(0, 212, 255, 0.5);
  background: linear-gradient(180deg, rgba(0, 212, 255, 0.06), var(--surface) 70%);
}
.pricing-tier {
  display: inline-block; font-size: 12px; font-weight: 600; letter-spacing: 0.4px;
  padding: 4px 10px; border-radius: 999px; margin-bottom: 14px;
  background: rgba(0, 212, 255, 0.1); color: var(--primary);
  border: 1px solid rgba(0, 212, 255, 0.35); align-self: flex-start;
}
.pricing-card.featured .pricing-tier {
  background: var(--primary); color: var(--bg); border-color: var(--primary);
}
.pricing-card h3 { font-size: 20px; margin-bottom: 6px; }
.pricing-tag { font-size: 14px; color: var(--text-dim); margin-bottom: 14px; }
.pricing-price { font-size: 26px; font-weight: 700; color: var(--text); margin-bottom: 16px; }
.pricing-price small { font-size: 13px; font-weight: 400; color: var(--text-dim); margin-left: 4px; }
.pricing-feats { list-style: none; margin: 0 0 20px; padding: 0; flex: 1; }
.pricing-feats li { position: relative; padding: 6px 0 6px 20px; color: var(--text-dim); font-size: 14px; line-height: 1.65; }
.pricing-feats li::before { content: "✓"; position: absolute; left: 0; top: 7px; color: var(--primary); font-weight: 700; }
.pricing-cta { display: block; text-align: center; padding: 11px 16px; border-radius: 8px; text-decoration: none; font-weight: 600; font-size: 15px; transition: all .2s; }
.pricing-cta.primary { background: var(--primary); color: var(--bg); }
.pricing-cta.primary:hover { background: #4be3ff; }
.pricing-cta.ghost { border: 1px solid var(--border); color: var(--text); }
.pricing-cta.ghost:hover { border-color: var(--primary); color: var(--primary); }

/* ============ 步骤 ============ */
.steps { list-style: none; display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 24px; counter-reset: s; }
.step {
  position: relative; background: var(--surface); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 32px 28px;
}
.step-num {
  font-size: 40px; font-weight: 800; line-height: 1;
  background: linear-gradient(120deg, var(--primary), var(--accent));
  -webkit-background-clip: text; background-clip: text; color: transparent; display: block; margin-bottom: 14px;
}
.step h3 { font-size: 20px; margin-bottom: 8px; }
.step p { color: var(--text-dim); font-size: 15px; }

/* ============ 案例 ============ */
.case-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 22px; }
.case { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 26px; transition: transform .25s, border-color .25s; }
.case:hover { transform: translateY(-6px); border-color: rgba(123, 97, 255, 0.4); }
.case-tag { display: inline-block; font-size: 12px; color: var(--accent); border: 1px solid rgba(123, 97, 255, 0.35); padding: 3px 10px; border-radius: 999px; margin-bottom: 12px; }
.case h3 { font-size: 18px; margin-bottom: 10px; }
.case p { color: var(--text-dim); font-size: 14px; margin-bottom: 16px; }
.case-metrics { list-style: none; display: flex; gap: 26px; }
.case-metrics strong { display: block; font-size: 22px; color: var(--primary); }
.case-metrics span { font-size: 12px; color: var(--text-dim); }

/* ============ 软文列表 ============ */
.post-list { display: grid; gap: 16px; max-width: 880px; margin: 0 auto; }
.post { display: block; background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 24px 26px; transition: border-color .25s, transform .25s; }
.post:hover { border-color: var(--primary); transform: translateX(4px); }
.post-date { font-size: 12px; color: var(--primary); letter-spacing: 1px; }
.post h3 { font-size: 19px; margin: 8px 0; }
.post p { color: var(--text-dim); font-size: 14px; }

/* ============ 联系方式 ============ */
.contact-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 20px; max-width: 900px; margin: 0 auto; }
.contact-item { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 24px; }
.contact-label { display: block; font-size: 13px; color: var(--text-dim); margin-bottom: 8px; }
.contact-value { font-size: 17px; font-weight: 600; color: var(--primary); word-break: break-all; }

/* ============ 页脚 ============ */
.site-footer { border-top: 1px solid var(--border); padding: 30px 0; background: var(--bg-alt); }
.footer-inner { display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: 10px; color: var(--text-dim); font-size: 14px; }
.beian a { color: var(--text-dim); }
.beian a:hover { color: var(--primary); }

/* ============ 滚动淡入 ============ */
.reveal { opacity: 0; transform: translateY(28px); transition: opacity .7s ease, transform .7s ease; }
.reveal.in { opacity: 1; transform: none; }

/* ============ 移动端 ============ */
@media (max-width: 820px) {
  .nav-links {
    position: fixed; top: 64px; left: 0; right: 0;
    flex-direction: column; gap: 0; background: var(--bg);
    border-bottom: 1px solid var(--border); padding: 0 24px;
    max-height: 0; overflow: hidden; transition: max-height .3s ease;
  }
  .nav-links.open { max-height: 320px; }
  .nav-links a { padding: 16px 0; border-bottom: 1px solid var(--border); }
  .nav-toggle { display: flex; }
  .hero-stats { gap: 28px; }
}