/* ===================================================================
   云矩科技官网  ·  全局样式
   设计变量集中在 :root，改品牌色只需改这里。
   零外部依赖（无 CDN、无外部字体），可直接丢到国内服务器离线运行。
   =================================================================== */

:root {
  --brand: #2563eb;          /* 主品牌色：科技蓝 */
  --brand-2: #06b6d4;        /* 辅助色：青 */
  --brand-deep: #1e3a8a;     /* 深蓝，用于 hero 背景 */
  --ink: #0f172a;            /* 主文字 */
  --ink-2: #475569;          /* 次级文字 */
  --ink-3: #94a3b8;          /* 弱文字 */
  --line: #e2e8f0;           /* 分割线 */
  --bg: #ffffff;
  --bg-soft: #f8fafc;        /* 浅灰底 */
  --bg-card: #ffffff;
  --radius: 14px;
  --shadow: 0 10px 30px rgba(15, 23, 42, 0.08);
  --shadow-lg: 0 20px 50px rgba(15, 23, 42, 0.14);
  --maxw: 1160px;
  --header-h: 64px;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  color: var(--ink);
  background: var(--bg);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }

.container {
  width: 100%;
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 20px;
}

/* ---------------- 顶部导航 ---------------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  height: var(--header-h);
  background: rgba(255, 255, 255, 0.86);
  backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid var(--line);
}
.nav {
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 18px;
  letter-spacing: 0.5px;
}
.brand .logo-mark {
  width: 30px; height: 30px;
  border-radius: 8px;
  background: linear-gradient(135deg, var(--brand), var(--brand-2));
  display: grid;
  place-items: center;
  color: #fff;
  font-weight: 800;
  font-size: 16px;
}
.brand small {
  display: block;
  font-size: 11px;
  font-weight: 500;
  color: var(--ink-3);
  letter-spacing: 0;
}
.nav-links {
  display: flex;
  align-items: center;
  gap: 28px;
}
.nav-links a {
  font-size: 15px;
  color: var(--ink-2);
  font-weight: 500;
  transition: color 0.2s;
}
.nav-links a:hover,
.nav-links a.active { color: var(--brand); }

.nav-cta {
  background: linear-gradient(135deg, var(--brand), var(--brand-2));
  color: #fff !important;
  padding: 9px 18px;
  border-radius: 999px;
  font-weight: 600;
  box-shadow: 0 8px 20px rgba(37, 99, 235, 0.28);
}
.nav-toggle {
  display: none;
  background: none;
  border: 0;
  font-size: 26px;
  cursor: pointer;
  color: var(--ink);
}

/* ---------------- Hero ---------------- */
.hero {
  position: relative;
  overflow: hidden;
  color: #fff;
  background:
    radial-gradient(1200px 600px at 80% -10%, rgba(6,182,212,0.35), transparent 60%),
    radial-gradient(900px 500px at 0% 0%, rgba(37,99,235,0.45), transparent 55%),
    linear-gradient(160deg, var(--brand-deep), #0b1530);
}
.hero::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255,255,255,0.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.04) 1px, transparent 1px);
  background-size: 44px 44px;
  mask-image: radial-gradient(circle at 50% 30%, #000, transparent 75%);
}
.hero .container { position: relative; z-index: 1; padding: 96px 20px 84px; }
.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  letter-spacing: 1px;
  color: #cbd5e1;
  background: rgba(255,255,255,0.08);
  border: 1px solid rgba(255,255,255,0.16);
  padding: 6px 14px;
  border-radius: 999px;
}
.hero h1 {
  font-size: clamp(32px, 5vw, 54px);
  line-height: 1.18;
  margin: 20px 0 16px;
  font-weight: 800;
  letter-spacing: 0.5px;
}
.hero h1 .grad {
  background: linear-gradient(90deg, #7dd3fc, #38bdf8);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.hero p.lead {
  font-size: clamp(16px, 2vw, 19px);
  color: #dbeafe;
  max-width: 640px;
}
.hero-actions { margin-top: 30px; display: flex; gap: 14px; flex-wrap: wrap; }
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 13px 26px;
  border-radius: 999px;
  font-weight: 600;
  font-size: 15px;
  cursor: pointer;
  transition: transform 0.15s, box-shadow 0.2s;
  border: 1px solid transparent;
}
.btn:hover { transform: translateY(-2px); }
.btn-primary {
  background: #fff;
  color: var(--brand-deep);
  box-shadow: 0 12px 30px rgba(0,0,0,0.25);
}
.btn-ghost {
  background: rgba(255,255,255,0.06);
  color: #fff;
  border-color: rgba(255,255,255,0.25);
}

/* ---------------- 通用区块 ---------------- */
section { padding: 76px 0; }
.section-soft { background: var(--bg-soft); }
.section-head { text-align: center; max-width: 720px; margin: 0 auto 48px; }
.section-head .tag {
  color: var(--brand);
  font-weight: 700;
  letter-spacing: 2px;
  font-size: 13px;
}
.section-head h2 {
  font-size: clamp(26px, 3.4vw, 38px);
  margin: 10px 0 12px;
  font-weight: 800;
}
.section-head p { color: var(--ink-2); font-size: 16px; margin: 0; }

/* 卡片网格 */
.grid { display: grid; gap: 22px; }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

.card {
  background: var(--bg-card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 28px;
  box-shadow: var(--shadow);
  transition: transform 0.2s, box-shadow 0.2s, border-color 0.2s;
}
.card:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); border-color: #c7d2fe; }
.card .ico {
  width: 48px; height: 48px;
  border-radius: 12px;
  background: linear-gradient(135deg, var(--brand), var(--brand-2));
  display: grid; place-items: center;
  color: #fff;
  margin-bottom: 16px;
}
.card h3 { margin: 0 0 8px; font-size: 19px; }
.card p { margin: 0; color: var(--ink-2); font-size: 15px; }

/* 数据与优势 */
.stats { display: grid; grid-template-columns: repeat(4, 1fr); gap: 22px; text-align: center; }
.stat .num {
  font-size: 40px; font-weight: 800;
  background: linear-gradient(135deg, var(--brand), var(--brand-2));
  -webkit-background-clip: text; background-clip: text; color: transparent;
}
.stat .label { color: var(--ink-2); font-size: 14px; margin-top: 4px; }

/* 双栏图文 */
.split { display: grid; grid-template-columns: 1.1fr 0.9fr; gap: 48px; align-items: center; }
.split .visual {
  border-radius: 18px;
  min-height: 320px;
  background: linear-gradient(160deg, var(--brand-deep), #0b1530);
  position: relative;
  overflow: hidden;
  box-shadow: var(--shadow-lg);
}
.split .visual::before {
  content: "";
  position: absolute; inset: 0;
  background-image:
    linear-gradient(rgba(255,255,255,0.06) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.06) 1px, transparent 1px);
  background-size: 36px 36px;
}
.split h2 { font-size: clamp(24px, 3vw, 34px); margin: 0 0 14px; font-weight: 800; }
.split p { color: var(--ink-2); margin: 0 0 16px; }
.feature-list { list-style: none; padding: 0; margin: 0; }
.feature-list li { display: flex; gap: 12px; padding: 9px 0; color: var(--ink-2); }
.feature-list li svg { flex: none; margin-top: 4px; color: var(--brand); }

/* 时间线（协会背景） */
.timeline { border-left: 2px solid var(--line); margin-left: 8px; padding-left: 24px; }
.timeline .item { position: relative; padding-bottom: 22px; }
.timeline .item::before {
  content: ""; position: absolute; left: -31px; top: 6px;
  width: 12px; height: 12px; border-radius: 50%;
  background: var(--brand); box-shadow: 0 0 0 4px #dbeafe;
}
.timeline .item h4 { margin: 0 0 2px; font-size: 16px; }
.timeline .item p { margin: 0; color: var(--ink-2); font-size: 14px; }

/* 联系表单 */
.contact-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 40px; }
.form-row { margin-bottom: 16px; }
.form-row label { display: block; font-size: 14px; font-weight: 600; margin-bottom: 6px; }
.form-row input, .form-row textarea {
  width: 100%; padding: 12px 14px; border: 1px solid var(--line);
  border-radius: 10px; font: inherit; color: var(--ink); background: #fff;
  transition: border-color 0.2s, box-shadow 0.2s;
}
.form-row input:focus, .form-row textarea:focus {
  outline: none; border-color: var(--brand); box-shadow: 0 0 0 3px #dbeafe;
}
.form-row textarea { min-height: 120px; resize: vertical; }
.info-card { background: var(--bg-soft); border: 1px solid var(--line); border-radius: var(--radius); padding: 26px; }
.info-card h3 { margin-top: 0; }
.info-item { display: flex; gap: 12px; padding: 10px 0; border-bottom: 1px dashed var(--line); }
.info-item:last-child { border-bottom: 0; }
.info-item .k { color: var(--ink-3); font-size: 13px; width: 64px; flex: none; }
.info-item .v { color: var(--ink); font-size: 15px; }

/* CTA 横幅 */
.cta-band {
  background: linear-gradient(135deg, var(--brand), var(--brand-2));
  border-radius: 20px;
  padding: 48px;
  text-align: center;
  color: #fff;
  box-shadow: var(--shadow-lg);
}
.cta-band h2 { font-size: clamp(24px, 3vw, 34px); margin: 0 0 10px; }
.cta-band p { margin: 0 0 24px; opacity: 0.92; }
.cta-band .btn-primary { background: #fff; color: var(--brand-deep); }

/* 页脚 */
.site-footer {
  background: #0b1530;
  color: #cbd5e1;
  padding: 54px 0 26px;
}
.footer-grid { display: grid; grid-template-columns: 1.6fr 1fr 1fr 1fr; gap: 32px; }
.site-footer h4 { color: #fff; font-size: 15px; margin: 0 0 14px; }
.site-footer a { color: #cbd5e1; font-size: 14px; display: block; padding: 5px 0; }
.site-footer a:hover { color: #fff; }
.footer-brand p { font-size: 14px; color: #94a3b8; max-width: 280px; }
.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.1);
  margin-top: 36px; padding-top: 18px;
  display: flex; justify-content: space-between; flex-wrap: wrap; gap: 8px;
  font-size: 13px; color: #94a3b8;
}

/* 面包屑 */
.crumb { padding: 18px 0; font-size: 13px; color: var(--ink-3); }
.crumb a:hover { color: var(--brand); }

/* ---------------- 响应式 ---------------- */
@media (max-width: 920px) {
  .grid-3, .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .stats { grid-template-columns: repeat(2, 1fr); }
  .split { grid-template-columns: 1fr; gap: 28px; }
  .contact-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 640px) {
  .nav-links {
    position: absolute; top: var(--header-h); left: 0; right: 0;
    background: #fff; flex-direction: column; align-items: flex-start;
    gap: 0; padding: 8px 20px 16px; border-bottom: 1px solid var(--line);
    box-shadow: var(--shadow); display: none;
  }
  .nav-links.open { display: flex; }
  .nav-links a { padding: 12px 0; width: 100%; }
  .nav-toggle { display: block; }
  .grid-2, .grid-3, .grid-4, .stats { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; }
  .cta-band { padding: 32px 22px; }
  section { padding: 56px 0; }
}