/* ===========================================================
   AI 落地服务 · 主站样式（深色科技风 v2）
   与 hub.html 统一视觉语言：墨蓝底 + 网格 + 柔光 + 渐变字
   四页共用：index / services / cases / caliber-card(内联覆写)
   =========================================================== */

:root {
  --acc: 56 189 248;          /* 青 · 主色 */
  --acc2: 167 139 250;        /* 紫 · 副色 */
  --ink: #eaf4ff;             /* 标题 */
  --body: #a4b4ca;            /* 正文 */
  --muted: #6d7d95;           /* 弱化 */
  --line: rgba(255, 255, 255, .10);
  --line-soft: rgba(255, 255, 255, .055);
  --panel-a: rgba(255, 255, 255, .048);
  --panel-b: rgba(255, 255, 255, .016);
  --mono: ui-monospace, SFMono-Regular, Consolas, "Liberation Mono", monospace;
  --radius: 14px;
  --brand: rgb(var(--acc));
  --brand-deep: #eaf4ff;
  --brand-soft: rgba(56, 189, 248, .12);
  --soft: rgba(255, 255, 255, .04);
}

html { background: #070b12; }
* { box-sizing: border-box; }

body {
  margin: 0;
  background: transparent;
  color: var(--body);
  font-family: -apple-system, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  font-size: 16px;
  line-height: 1.78;
  -webkit-font-smoothing: antialiased;
  position: relative;
  overflow-x: hidden;
}

/* 网格底纹（固定层，位于内容之下） */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(122, 172, 242, .062) 1px, transparent 1px),
    linear-gradient(90deg, rgba(122, 172, 242, .062) 1px, transparent 1px);
  background-size: 46px 46px;
  -webkit-mask-image: radial-gradient(72% 62% at 50% 14%, #000 0%, transparent 82%);
  mask-image: radial-gradient(72% 62% at 50% 14%, #000 0%, transparent 82%);
}

/* 顶部柔光（多层渐变衰减，不用 blur —— 无 GPU 下 blur 会退化成硬边方块） */
body::after {
  content: "";
  position: fixed;
  left: 50%;
  top: -260px;
  width: 1180px;
  height: 660px;
  transform: translateX(-50%);
  z-index: -1;
  pointer-events: none;
  background:
    radial-gradient(closest-side, rgba(56, 189, 248, .17), transparent 76%),
    radial-gradient(closest-side at 72% 60%, rgba(167, 139, 250, .13), transparent 72%);
}

a { color: rgb(var(--acc)); text-decoration: none; transition: color .2s ease; }
a:hover { color: #bfe6ff; text-decoration: underline; }
.wrap { max-width: 880px; margin: 0 auto; padding: 0 22px; }

/* ---------- 顶栏 ---------- */
.site-nav {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(8, 13, 22, .72);
  backdrop-filter: blur(14px) saturate(150%);
  -webkit-backdrop-filter: blur(14px) saturate(150%);
  border-bottom: 1px solid var(--line);
}
.site-nav .wrap {
  display: flex; align-items: center; justify-content: space-between;
  height: 64px; gap: 16px;
}
.brand {
  font-size: 15px; font-weight: 700; color: var(--ink);
  letter-spacing: .01em; display: flex; align-items: center; gap: 9px;
  white-space: nowrap;
}
.brand::before {
  content: ""; width: 8px; height: 8px; border-radius: 50%;
  background: rgb(var(--acc));
  box-shadow: 0 0 12px rgba(56, 189, 248, .85);
  flex: none;
}
.nav-links { display: flex; gap: 20px; font-size: 14px; }
.nav-links a { color: var(--body); position: relative; white-space: nowrap; }
.nav-links a:hover { color: #fff; text-decoration: none; }
.nav-links a.active { color: rgb(var(--acc)); font-weight: 600; }
.nav-links a.active::after {
  content: ""; position: absolute; left: 0; right: 0; bottom: -20px;
  height: 2px; border-radius: 2px;
  background: linear-gradient(90deg, transparent, rgb(var(--acc)), transparent);
}

/* ---------- 文字 ---------- */
h1 {
  font-size: clamp(27px, 4.3vw, 41px);
  font-weight: 800; line-height: 1.32; letter-spacing: -.02em;
  margin: 0 0 18px;
  background: linear-gradient(118deg, #eaf4ff 0%, #c2dbff 40%, rgb(var(--acc)) 100%);
  -webkit-background-clip: text; background-clip: text;
  -webkit-text-fill-color: transparent;
  padding-bottom: 2px;
}
h2 {
  font-size: 21px; font-weight: 700; margin: 0 0 22px; color: var(--ink);
  display: flex; align-items: center; gap: 11px; letter-spacing: -.01em;
}
h2::before {
  content: ""; width: 4px; height: 18px; border-radius: 2px; flex: none;
  background: linear-gradient(180deg, rgb(var(--acc)), rgb(var(--acc2)));
  box-shadow: 0 0 14px rgba(56, 189, 248, .5);
}
h3 { font-size: 15px; font-weight: 650; margin: 0 0 8px; color: var(--ink); }
p { margin: 0 0 12px; }
.lede { font-size: 17px; color: var(--body); margin: 0 0 10px; }
.sub { font-size: 14px; color: var(--muted); margin: 0; }
strong, b { color: #dce9fa; font-weight: 650; }
code { font-family: var(--mono); font-size: .92em; color: #cfe6ff; }

/* ---------- Hero / 区块 ---------- */
header.hero {
  position: relative;
  padding: 78px 0 62px;
  border-bottom: 1px solid var(--line-soft);
  overflow: hidden;
}
header.hero::after {
  content: ""; position: absolute; inset: -40% -10% auto -10%; height: 150%;
  pointer-events: none; z-index: -1;
  background:
    radial-gradient(circle at 16% 34%, rgba(56, 189, 248, .21), transparent 54%),
    radial-gradient(circle at 86% 4%, rgba(167, 139, 250, .17), transparent 50%);
}
section {
  position: relative;
  padding: 54px 0;
  border-bottom: 1px solid var(--line-soft);
}

/* ---------- 卡片 ---------- */
.grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(232px, 1fr)); gap: 16px; }
.card {
  position: relative; overflow: hidden;
  border: 1px solid var(--line); border-radius: var(--radius);
  padding: 22px 22px 24px;
  background: linear-gradient(180deg, var(--panel-a), var(--panel-b));
  transition: transform .28s cubic-bezier(.2, .7, .3, 1), border-color .28s ease, box-shadow .28s ease;
}
.card::after {
  content: ""; position: absolute; top: 0; left: -62%; width: 42%; height: 100%;
  transform: skewX(-18deg); pointer-events: none;
  background: linear-gradient(100deg, transparent, rgba(255, 255, 255, .075), transparent);
  transition: left .62s ease;
}
.card:hover {
  transform: translateY(-4px);
  border-color: rgba(56, 189, 248, .42);
  box-shadow: 0 20px 44px -20px rgba(56, 189, 248, .5);
}
.card:hover::after { left: 122%; }
.card p { font-size: 14px; color: var(--body); margin: 0; }
.card .tag {
  display: inline-block; font-size: 12px; font-weight: 600; letter-spacing: .02em;
  color: rgb(var(--acc)); background: rgba(56, 189, 248, .12);
  border: 1px solid rgba(56, 189, 248, .28);
  border-radius: 999px; padding: 3px 11px; margin-bottom: 12px;
}

/* ---------- 软底区块 ---------- */
.soft {
  background: linear-gradient(180deg, var(--panel-a), var(--panel-b));
  border: 1px solid var(--line); border-radius: var(--radius);
  padding: 22px 26px;
}
.soft ul { margin: 0; padding-left: 20px; }
.soft li { margin: 8px 0; font-size: 15px; color: var(--body); }
.soft li::marker { color: rgb(var(--acc)); }

/* ---------- 数字卡 ---------- */
.stats { display: grid; grid-template-columns: repeat(auto-fit, minmax(168px, 1fr)); gap: 14px; }
.stat {
  background: linear-gradient(180deg, var(--panel-a), var(--panel-b));
  border: 1px solid var(--line); border-radius: var(--radius);
  padding: 18px 20px;
}
.stat .num {
  font-family: var(--mono);
  font-size: 26px; font-weight: 800; line-height: 1.25; letter-spacing: -.02em;
  background: linear-gradient(118deg, #eaf4ff, rgb(var(--acc)));
  -webkit-background-clip: text; background-clip: text;
  -webkit-text-fill-color: transparent;
}
.stat .cap { font-size: 13px; color: var(--muted); margin-top: 4px; line-height: 1.6; }

/* ---------- 表格 ---------- */
table { width: 100%; border-collapse: collapse; font-size: 14px; }
th, td { padding: 12px; text-align: left; border-bottom: 1px solid var(--line-soft); color: var(--body); }
th {
  font-weight: 600; font-size: 13px; letter-spacing: .02em; color: var(--ink);
  background: rgba(255, 255, 255, .04);
}
tbody tr { transition: background .2s ease; }
tbody tr:hover { background: rgba(255, 255, 255, .028); }
tbody tr:last-child td { border-bottom: none; }

/* ---------- 步骤 ---------- */
.steps { counter-reset: s; margin: 0; padding: 0; list-style: none; }
.steps li { counter-increment: s; position: relative; padding-left: 44px; margin-bottom: 20px; }
.steps li::before {
  content: counter(s); position: absolute; left: 0; top: 1px;
  width: 28px; height: 28px; border-radius: 50%;
  background: rgba(56, 189, 248, .13);
  border: 1px solid rgba(56, 189, 248, .32);
  color: rgb(var(--acc));
  font-family: var(--mono); font-size: 13px; font-weight: 700;
  text-align: center; line-height: 26px;
  box-shadow: 0 0 16px rgba(56, 189, 248, .22);
}
.steps strong { display: block; font-size: 15px; color: var(--ink); margin-bottom: 2px; }
.steps span { font-size: 14px; color: var(--body); }

/* ---------- CTA / 联系 ---------- */
.cta {
  position: relative; padding: 70px 0 86px; text-align: center;
  border-bottom: 1px solid var(--line-soft);
}
.cta h2 { justify-content: center; }
.cta h2::before { display: none; }
.cta::after {
  content: ""; position: absolute; left: 50%; bottom: -160px;
  width: 760px; height: 380px; transform: translateX(-50%);
  pointer-events: none; z-index: -1;
  background: radial-gradient(closest-side, rgba(167, 139, 250, .15), transparent 74%);
}
.contact {
  display: inline-block; margin-top: 10px;
  border: 1px solid var(--line); border-radius: 999px;
  padding: 14px 28px; background: rgba(255, 255, 255, .04);
  font-size: 14.5px; color: var(--body);
}
.note { font-size: 13px; color: var(--muted); margin-top: 14px; }
.btn {
  display: inline-block; margin-top: 6px;
  background: linear-gradient(118deg, rgb(var(--acc)), rgb(var(--acc2)));
  color: #06121f; font-weight: 700; font-size: 15px;
  border-radius: 999px; padding: 12px 28px;
  box-shadow: 0 16px 34px -16px rgba(56, 189, 248, .8);
  transition: transform .2s ease, box-shadow .2s ease;
}
.btn:hover {
  color: #06121f; text-decoration: none; transform: translateY(-2px);
  box-shadow: 0 22px 42px -16px rgba(56, 189, 248, .95);
}

/* ---------- 页脚 ---------- */
footer.site-foot {
  border-top: 1px solid var(--line-soft);
  padding: 30px 0 60px; font-size: 13px; color: var(--muted);
  position: relative;
}
footer.site-foot .wrap { display: flex; flex-wrap: wrap; gap: 16px; justify-content: space-between; }
footer.site-foot a { color: var(--muted); }
footer.site-foot a:hover { color: rgb(var(--acc)); }

/* ---------- 滚动进度条 ---------- */
.scroll-progress {
  position: fixed; top: 0; left: 0; height: 2px; width: 0; z-index: 100;
  pointer-events: none;
  background: linear-gradient(90deg, rgb(var(--acc)), rgb(var(--acc2)));
  box-shadow: 0 0 12px rgba(56, 189, 248, .8);
}

@media (max-width: 620px) {
  h1 { font-size: 25px; }
  header.hero { padding: 44px 0 34px; }
  section { padding: 40px 0; }
  .cta { padding: 52px 0 68px; }
  .site-nav .wrap { height: auto; padding: 12px 0; flex-direction: column; align-items: flex-start; gap: 10px; }
  .nav-links { flex-wrap: wrap; gap: 14px; }
  .nav-links a.active::after { display: none; }
  .soft { padding: 18px 18px; }
}

@media (prefers-reduced-motion: reduce) {
  * { transition: none !important; animation: none !important; }
}

/* ---------- 打印：回退浅色 ---------- */
@media print {
  html, body { background: #fff !important; color: #1f2328 !important; }
  body::before, body::after, .scroll-progress { display: none !important; }
  header.hero::after, .cta::after { display: none !important; }
  .site-nav { position: static; background: #fff; backdrop-filter: none; }
  h1, h2, h3, .stat .num, strong, b {
    background: none !important; -webkit-text-fill-color: #1f2328 !important; color: #1f2328 !important;
  }
  .lede, p, li, td, th { color: #374151 !important; }
  .card, .soft, .stat, th {
    background: #f6f7f9 !important; border-color: #e5e7eb !important;
    box-shadow: none !important;
  }
  .card::after { display: none !important; }
  .brand::before, h2::before { box-shadow: none !important; }
  footer.site-foot, .sub, .note { color: #6b7280 !important; }
}