/* ============================================================
   江苏单窗信息科技有限公司 · 官网样式
   风格：简约大气 / 科技蓝 / 大留白
   ============================================================ */

:root {
  --primary: #1652F0;
  --primary-dark: #0E3BC0;
  --primary-light: #EEF3FF;
  --ink: #17213A;
  --ink-soft: #4A5570;
  --ink-mute: #8B94AC;
  --line: #E6EAF2;
  --bg: #FFFFFF;
  --bg-soft: #F7F9FC;
  --radius: 14px;
  --shadow: 0 10px 40px rgba(23, 33, 58, .07);
  --shadow-hover: 0 16px 48px rgba(22, 82, 240, .14);
  --maxw: 1180px;
}

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

html { scroll-behavior: smooth; }

body {
  font-family: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  color: var(--ink);
  background: var(--bg);
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
}

a { text-decoration: none; color: inherit; }
ul { list-style: none; }
img, svg { display: block; max-width: 100%; }

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

/* ---------- 顶部导航 ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, .92);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--line);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}

.brand { display: flex; align-items: center; gap: 12px; }

.brand-mark {
  width: 40px; height: 40px;
  border-radius: 10px;
  background: linear-gradient(135deg, var(--primary) 0%, #6FA0FF 100%);
  display: flex; align-items: center; justify-content: center;
  color: #fff; font-weight: 700; font-size: 18px;
  letter-spacing: -1px;
  flex-shrink: 0;
}

.brand-logo { height: 40px; width: auto; flex-shrink: 0; }

.brand-name { font-size: 17px; font-weight: 700; letter-spacing: .5px; }
.brand-name small { display: block; font-size: 11px; font-weight: 400; color: var(--ink-mute); letter-spacing: 1.5px; }

.nav-links { display: flex; align-items: center; gap: 8px; }

.nav-links a {
  padding: 8px 18px;
  border-radius: 8px;
  font-size: 15px;
  color: var(--ink-soft);
  transition: all .2s;
}

.nav-links a:hover { color: var(--primary); background: var(--primary-light); }
.nav-links a.active { color: var(--primary); font-weight: 600; }

.nav-cta {
  margin-left: 16px;
  padding: 9px 22px !important;
  background: var(--primary) !important;
  color: #fff !important;
  border-radius: 8px;
  font-weight: 500;
}

.nav-cta:hover { background: var(--primary-dark) !important; box-shadow: var(--shadow-hover); }

.nav-toggle { display: none; flex-direction: column; gap: 5px; cursor: pointer; padding: 8px; }
.nav-toggle span { width: 22px; height: 2px; background: var(--ink); border-radius: 2px; transition: .2s; }

/* ---------- Hero 首屏 ---------- */
.hero {
  position: relative;
  overflow: hidden;
  background:
    radial-gradient(900px 420px at 85% -10%, rgba(22, 82, 240, .10), transparent 60%),
    radial-gradient(700px 380px at -5% 110%, rgba(111, 160, 255, .12), transparent 60%),
    var(--bg-soft);
  padding: 110px 0 100px;
}

.hero-inner { display: flex; align-items: center; gap: 60px; }
.hero-text { flex: 1.15; min-width: 0; }

.hero-tag {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 6px 16px;
  background: var(--primary-light);
  color: var(--primary);
  border: 1px solid rgba(22, 82, 240, .18);
  border-radius: 999px;
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 1px;
  margin-bottom: 26px;
}

.hero-tag i { width: 7px; height: 7px; border-radius: 50%; background: var(--primary); display: inline-block; }

.hero h1 {
  font-size: 46px;
  line-height: 1.28;
  font-weight: 700;
  letter-spacing: 1px;
  margin-bottom: 22px;
}

.hero h1 em { font-style: normal; color: var(--primary); }

/* 首屏标语轮播 */
.hero-slogan { display: grid; margin-bottom: 22px; }
.hero-slogan .slogan-item { grid-area: 1 / 1; opacity: 0; transition: opacity .9s ease; }
.hero-slogan .slogan-item.active { opacity: 1; }

.hero p.lead {
  font-size: 17px;
  color: var(--ink-soft);
  max-width: 540px;
  margin-bottom: 38px;
}

.hero-actions { display: flex; gap: 16px; flex-wrap: wrap; }

.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  padding: 13px 34px;
  border-radius: 10px;
  font-size: 15px;
  font-weight: 500;
  transition: all .25s;
  cursor: pointer;
  border: none;
}

.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-dark); box-shadow: var(--shadow-hover); transform: translateY(-1px); }

.btn-ghost { background: transparent; color: var(--ink); border: 1px solid var(--line); }
.btn-ghost:hover { border-color: var(--primary); color: var(--primary); }

.hero-stats {
  display: flex;
  gap: 48px;
  margin-top: 56px;
  flex-wrap: wrap;
}

.stat-num { font-size: 34px; font-weight: 700; color: var(--primary); font-variant-numeric: tabular-nums; }
.stat-num small { font-size: 16px; font-weight: 600; margin-left: 2px; }
.stat-label { font-size: 13px; color: var(--ink-mute); letter-spacing: .5px; }

.hero-visual { flex: 1; min-width: 0; }

/* ---------- 通用区块 ---------- */
.section { padding: 96px 0; }
.section.alt { background: var(--bg-soft); }

.section-head { text-align: center; max-width: 680px; margin: 0 auto 60px; }

.eyebrow {
  display: inline-block;
  font-size: 13px;
  font-weight: 600;
  color: var(--primary);
  letter-spacing: 4px;
  margin-bottom: 14px;
}

.section-head h2 { font-size: 34px; font-weight: 700; letter-spacing: 1px; margin-bottom: 16px; }
.section-head p { color: var(--ink-soft); font-size: 16px; }

/* ---------- 卡片网格 ---------- */
.grid { display: grid; gap: 28px; }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

.card {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 36px 30px;
  transition: all .25s;
}

.card:hover { box-shadow: var(--shadow-hover); border-color: rgba(22, 82, 240, .35); transform: translateY(-4px); }

.card-icon {
  width: 52px; height: 52px;
  border-radius: 12px;
  background: var(--primary-light);
  color: var(--primary);
  display: flex; align-items: center; justify-content: center;
  margin-bottom: 22px;
}

.card h3 { font-size: 19px; font-weight: 600; margin-bottom: 12px; letter-spacing: .5px; }
.card p { font-size: 14.5px; color: var(--ink-soft); }
.card .num { font-size: 13px; color: var(--ink-mute); letter-spacing: 2px; margin-bottom: 10px; }

/* ---------- 数字滚动带 ---------- */
.value-strip { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.value-item {
  text-align: center;
  padding: 40px 24px;
  border-radius: var(--radius);
  background: #fff;
  border: 1px solid var(--line);
  transition: all .25s;
}
.value-item:hover { transform: translateY(-4px); box-shadow: var(--shadow); }
.value-item .word { font-size: 30px; font-weight: 700; color: var(--primary); margin-bottom: 8px; letter-spacing: 4px; }
.value-item p { font-size: 14px; color: var(--ink-soft); }

/* ---------- 横幅 CTA ---------- */
.cta-band {
  background: linear-gradient(120deg, var(--primary-dark) 0%, var(--primary) 55%, #4E84FF 100%);
  border-radius: 20px;
  padding: 64px 56px;
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 40px;
  flex-wrap: wrap;
  position: relative;
  overflow: hidden;
}
.cta-band::after {
  content: "";
  position: absolute; right: -80px; top: -80px;
  width: 300px; height: 300px;
  border-radius: 50%;
  background: rgba(255, 255, 255, .08);
  pointer-events: none; /* 装饰圆不拦截点击，否则会挡住 CTA 按钮 */
}
.cta-band > * { position: relative; z-index: 1; }
.cta-band h2 { font-size: 30px; font-weight: 700; margin-bottom: 12px; letter-spacing: 1px; }
.cta-band p { opacity: .85; font-size: 15.5px; }
.cta-band .btn { background: #fff; color: var(--primary); }
.cta-band .btn:hover { transform: translateY(-2px); box-shadow: 0 12px 30px rgba(0,0,0,.2); }

/* ---------- 页面小标题（子页 hero） ---------- */
.page-hero {
  background:
    radial-gradient(700px 300px at 90% 0%, rgba(22, 82, 240, .10), transparent 60%),
    var(--bg-soft);
  border-bottom: 1px solid var(--line);
  padding: 78px 0 64px;
  text-align: center;
}
.page-hero .eyebrow { letter-spacing: 4px; }
.page-hero h1 { font-size: 38px; font-weight: 700; letter-spacing: 1px; margin-bottom: 16px; }
.page-hero p { color: var(--ink-soft); max-width: 620px; margin: 0 auto; font-size: 16px; }

/* ---------- 时间线 / 列表 ---------- */
.feature-row {
  display: flex;
  gap: 56px;
  align-items: center;
}
.feature-row + .feature-row { margin-top: 72px; }
.feature-row.reverse { flex-direction: row-reverse; }
.feature-text { flex: 1; }
.feature-visual { flex: 1; }

.feature-text h3 { font-size: 26px; font-weight: 700; margin-bottom: 18px; letter-spacing: .5px; }
.feature-text p { color: var(--ink-soft); font-size: 15.5px; margin-bottom: 20px; }
.feature-text ul li {
  position: relative;
  padding-left: 26px;
  margin-bottom: 10px;
  font-size: 15px;
  color: var(--ink-soft);
}
.feature-text ul li::before {
  content: "";
  position: absolute; left: 0; top: 9px;
  width: 8px; height: 8px;
  border-radius: 2px;
  background: var(--primary);
}

/* ---------- 表格类信息 ---------- */
.spec-table { width: 100%; border-collapse: collapse; background: #fff; border-radius: var(--radius); overflow: hidden; box-shadow: var(--shadow); }
.spec-table th, .spec-table td { padding: 18px 26px; text-align: left; font-size: 15px; border-bottom: 1px solid var(--line); }
.spec-table th { background: var(--bg-soft); color: var(--ink); font-weight: 600; white-space: nowrap; }
.spec-table td { color: var(--ink-soft); }
.spec-table tr:last-child td { border-bottom: none; }

/* ---------- 联系表单 ---------- */
.contact-wrap { display: grid; grid-template-columns: 1fr 1.3fr; gap: 48px; align-items: start; }

.contact-card {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 36px 32px;
}
.contact-card h3 { font-size: 18px; font-weight: 600; margin-bottom: 24px; }

.contact-item { display: flex; gap: 16px; margin-bottom: 24px; }
.contact-item:last-child { margin-bottom: 0; }
.contact-item .ci-icon {
  width: 44px; height: 44px; flex-shrink: 0;
  border-radius: 10px;
  background: var(--primary-light);
  color: var(--primary);
  display: flex; align-items: center; justify-content: center;
}
.contact-item .ci-label { font-size: 12.5px; color: var(--ink-mute); letter-spacing: 1px; }
.contact-item .ci-value { font-size: 15px; font-weight: 500; }

.form-card {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 40px 38px;
  box-shadow: var(--shadow);
}
.form-card h3 { font-size: 20px; font-weight: 700; margin-bottom: 8px; }
.form-card > p { font-size: 14px; color: var(--ink-mute); margin-bottom: 28px; }

.form-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; }
.form-field { display: flex; flex-direction: column; gap: 8px; }
.form-field.full { grid-column: 1 / -1; }
.form-field label { font-size: 13.5px; font-weight: 500; color: var(--ink-soft); }
.form-field input, .form-field select, .form-field textarea {
  padding: 12px 16px;
  border: 1px solid var(--line);
  border-radius: 10px;
  font-size: 14.5px;
  font-family: inherit;
  color: var(--ink);
  background: var(--bg-soft);
  transition: all .2s;
  outline: none;
}
.form-field input:focus, .form-field select:focus, .form-field textarea:focus {
  border-color: var(--primary);
  background: #fff;
  box-shadow: 0 0 0 3px rgba(22, 82, 240, .12);
}
.form-field textarea { min-height: 120px; resize: vertical; }
.form-card .btn { width: 100%; margin-top: 24px; font-size: 16px; padding: 14px; }
.form-tip { text-align: center; font-size: 13px; color: var(--ink-mute); margin-top: 16px; }

/* ---------- 页脚 ---------- */
.site-footer { background: #101733; color: #A7B0C8; padding: 72px 0 0; }

.footer-grid { display: grid; grid-template-columns: 1.6fr 1fr 1fr 1fr; gap: 48px; padding-bottom: 56px; }

.site-footer .brand-name { color: #fff; }

/* ---------- 页脚商务微信二维码 ---------- */
.footer-qr { margin-top: 20px; }
.footer-qr img {
  width: 96px; height: 96px;
  border-radius: 8px;
  background: #fff; padding: 5px;
}
.footer-qr span { display: block; margin-top: 8px; font-size: 12px; color: #A7B0C8; }
.site-footer .brand-name small { color: #6B7590; }
.site-footer .brand-mark { background: linear-gradient(135deg, #3D74FF, #6FA0FF); }
.site-footer .brand-logo { height: 36px; }

.footer-about { font-size: 14px; margin-top: 20px; max-width: 320px; }

.footer-col h4 { color: #fff; font-size: 15px; font-weight: 600; margin-bottom: 20px; letter-spacing: 1px; }
.footer-col ul li { margin-bottom: 12px; }
.footer-col ul li a { font-size: 14px; transition: color .2s; }
.footer-col ul li a:hover { color: #fff; }

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, .08);
  padding: 22px 0;
  display: flex;
  justify-content: space-between;
  gap: 12px;
  flex-wrap: wrap;
  font-size: 13px;
  color: #6B7590;
  align-items: center;
}

/* 页脚右侧信息组（ICP 备案号 + 产品标识） */
.footer-meta {
  display: inline-flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px;
}
.footer-meta .sep { color: #3D4760; }
.footer-meta a {
  color: #8A94AC;
  transition: color .2s;
  border-bottom: 1px solid transparent;
}
.footer-meta a:hover { color: #fff; border-bottom-color: rgba(255, 255, 255, .45); }

/* ---------- 插画容器 ---------- */
.illustration { width: 100%; }

/* ---------- 动画 ---------- */
.reveal { opacity: 0; transform: translateY(24px); transition: all .7s cubic-bezier(.2, .7, .3, 1); }
.reveal.visible { opacity: 1; transform: none; }

/* ---------- 响应式 ---------- */
@media (max-width: 1024px) {
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .hero h1 { font-size: 38px; }
}

@media (max-width: 860px) {
  .hero-inner { flex-direction: column; gap: 48px; }
  .hero { padding: 72px 0 64px; }
  .grid-3, .grid-2, .value-strip { grid-template-columns: 1fr; }
  .feature-row, .feature-row.reverse { flex-direction: column; gap: 32px; }
  .contact-wrap { grid-template-columns: 1fr; }
  .form-grid { grid-template-columns: 1fr; }

  .nav-toggle { display: flex; }
  .nav-links {
    display: none;
    position: absolute;
    top: 72px; left: 0; right: 0;
    background: #fff;
    border-bottom: 1px solid var(--line);
    flex-direction: column;
    padding: 16px 24px 24px;
    align-items: stretch;
    gap: 4px;
  }
  .nav-links.open { display: flex; }
  .nav-links a { padding: 12px 14px; }
  .nav-cta { margin-left: 0; margin-top: 8px; text-align: center; }
}