:root {
  --bg: #ffffff;
  --bg-alt: #f5f8fa;
  --ink: #10233a;
  --ink-soft: #4d6480;
  --line: #e2e9f0;
  --brand: #0f7c8a;
  --brand-deep: #0b5c68;
  --brand-soft: #e6f4f5;
  --radius: 14px;
  --shadow: 0 10px 30px rgba(16, 35, 58, .08);
  --max: 1140px;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: "Helvetica Neue", "PingFang SC", "Microsoft YaHei", sans-serif;
  font-size: 16px;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
}

img { max-width: 100%; display: block; }

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

h1, h2, h3 { line-height: 1.3; margin: 0 0 .6em; letter-spacing: -.02em; }
h1 { font-size: clamp(2rem, 4.2vw, 3.1rem); }
h2 { font-size: clamp(1.5rem, 2.8vw, 2.1rem); }
h3 { font-size: 1.15rem; }
p { margin: 0 0 1em; }

ul { margin: 0; padding: 0; list-style: none; }

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

.eyebrow {
  margin: 0 0 .8em;
  color: var(--brand);
  font-size: .82rem;
  font-weight: 700;
  letter-spacing: .16em;
  text-transform: uppercase;
}

/* 头部导航：滚动后加背景与阴影，由 JS 切换 .is-scrolled */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255, 255, 255, .88);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid transparent;
  transition: border-color .25s, box-shadow .25s;
}

.site-header.is-scrolled {
  border-bottom-color: var(--line);
  box-shadow: 0 4px 20px rgba(16, 35, 58, .06);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 68px;
}

.brand { display: flex; align-items: center; gap: 10px; }

.brand-mark {
  width: 38px;
  height: 38px;
  display: grid;
  place-items: center;
  border-radius: 10px;
  background: linear-gradient(135deg, var(--brand), var(--brand-deep));
  color: #fff;
  font-weight: 800;
  font-size: .95rem;
  letter-spacing: .04em;
}

.brand-text { display: flex; flex-direction: column; line-height: 1.2; }
.brand-text strong { font-size: 1.02rem; }
.brand-text em {
  font-style: normal;
  font-size: .68rem;
  color: var(--ink-soft);
  letter-spacing: .18em;
}

.nav { display: flex; align-items: center; gap: 28px; }

.nav a {
  font-size: .93rem;
  color: var(--ink-soft);
  transition: color .2s;
}

.nav a:hover { color: var(--brand); }

.nav .nav-cta {
  padding: 8px 18px;
  border-radius: 999px;
  background: var(--brand);
  color: #fff;
}

.nav .nav-cta:hover { background: var(--brand-deep); color: #fff; }

.nav-toggle {
  display: none;
  width: 42px;
  height: 42px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: #fff;
  cursor: pointer;
  padding: 11px 10px;
}

.nav-toggle span {
  display: block;
  height: 2px;
  background: var(--ink);
  border-radius: 2px;
}

.nav-toggle span + span { margin-top: 5px; }

/* 按钮 */
.btn {
  display: inline-block;
  padding: 12px 26px;
  border-radius: 999px;
  font-size: .95rem;
  font-weight: 600;
  transition: transform .2s, background .2s, color .2s;
}

.btn:hover { transform: translateY(-2px); }
.btn-primary { background: var(--brand); color: #fff; box-shadow: var(--shadow); }
.btn-primary:hover { background: var(--brand-deep); }
.btn-ghost { border: 1px solid var(--line); color: var(--ink); }
.btn-ghost:hover { border-color: var(--brand); color: var(--brand); }

/* 首屏 */
.hero {
  padding: 84px 0 72px;
  background:
    radial-gradient(900px 420px at 12% -10%, var(--brand-soft), transparent 70%),
    linear-gradient(180deg, #fbfdfe, #fff);
}

.hero-inner {
  display: grid;
  grid-template-columns: 1.05fr .95fr;
  gap: 56px;
  align-items: center;
}

.hero-copy .lead {
  font-size: 1.05rem;
  color: var(--ink-soft);
  max-width: 34em;
}

.hero-actions { display: flex; gap: 14px; flex-wrap: wrap; margin: 28px 0 36px; }

.hero-stats {
  display: flex;
  gap: 34px;
  flex-wrap: wrap;
  padding-top: 26px;
  border-top: 1px solid var(--line);
}

.hero-stats strong { display: block; font-size: 1.05rem; }
.hero-stats span { font-size: .84rem; color: var(--ink-soft); }

.hero-visual img {
  border-radius: 18px;
  box-shadow: var(--shadow);
}

/* 通用区块 */
.section { padding: 84px 0; }
.section-alt { background: var(--bg-alt); }

.section-head { max-width: 44em; margin-bottom: 48px; }
.section-desc { color: var(--ink-soft); margin: 0; }

.grid { display: grid; gap: 24px; }
.grid-3 { grid-template-columns: repeat(3, 1fr); }

.card {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 28px 24px;
  transition: transform .25s, box-shadow .25s, border-color .25s;
}

.card:hover {
  transform: translateY(-4px);
  border-color: transparent;
  box-shadow: var(--shadow);
}

.card-icon {
  width: 40px;
  height: 40px;
  display: grid;
  place-items: center;
  margin-bottom: 16px;
  border-radius: 10px;
  background: var(--brand-soft);
  color: var(--brand-deep);
  font-weight: 800;
  font-size: .85rem;
}

.card p { margin: 0; color: var(--ink-soft); font-size: .94rem; }

/* 产品 */
.product {
  display: grid;
  grid-template-columns: .95fr 1.05fr;
  gap: 48px;
  align-items: center;
  padding: 36px;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 18px;
}

.product + .product { margin-top: 28px; }

.product-media img { border-radius: 12px; box-shadow: var(--shadow); }

.tag {
  display: inline-block;
  margin: 0 0 12px;
  padding: 4px 12px;
  border-radius: 999px;
  background: var(--brand-soft);
  color: var(--brand-deep);
  font-size: .78rem;
  font-weight: 700;
}

.product-body > p { color: var(--ink-soft); }
.product-body h3 { font-size: 1.4rem; color: var(--ink); }

.feature-list { margin: 18px 0; }

.feature-list li {
  position: relative;
  padding-left: 22px;
  margin-bottom: 10px;
  font-size: .94rem;
  color: var(--ink-soft);
}

.feature-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: .62em;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--brand);
}

.stack-line {
  margin: 0;
  padding-top: 16px;
  border-top: 1px dashed var(--line);
  font-size: .84rem;
  color: var(--ink-soft);
}

/* 技术栈 */
.tech-groups { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }

.tech-group {
  padding: 26px 24px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--bg-alt);
}

.chips { display: flex; flex-wrap: wrap; gap: 8px; }

.chips li {
  padding: 6px 14px;
  border-radius: 999px;
  background: #fff;
  border: 1px solid var(--line);
  font-size: .85rem;
  color: var(--ink-soft);
}

/* 关于我们 */
.about-inner {
  display: grid;
  grid-template-columns: 1.1fr .9fr;
  gap: 56px;
  align-items: center;
}

.about-copy p { color: var(--ink-soft); }

.value-list { margin-top: 22px; }

.value-list li {
  padding: 14px 0;
  border-top: 1px solid var(--line);
  font-size: .94rem;
  color: var(--ink-soft);
}

.value-list strong { color: var(--ink); }

.about-visual img { border-radius: 18px; box-shadow: var(--shadow); }

/* 联系我们 */
.contact-card {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  padding: 48px;
  border-radius: 20px;
  background: linear-gradient(135deg, var(--brand-deep), var(--brand));
  color: #fff;
}

.contact-card h2 { margin-bottom: .4em; }
.contact-text p { margin: 0; color: rgba(255, 255, 255, .82); }

.contact-list li {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  padding: 13px 0;
  border-bottom: 1px solid rgba(255, 255, 255, .22);
  font-size: .94rem;
}

.contact-label { color: rgba(255, 255, 255, .75); }
.contact-value { font-weight: 600; text-align: right; }

/* 页脚 */
.site-footer {
  padding: 34px 0;
  border-top: 1px solid var(--line);
  background: var(--bg-alt);
}

.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  flex-wrap: wrap;
}

.footer-brand { display: flex; flex-direction: column; }
.footer-brand span { font-size: .8rem; color: var(--ink-soft); }
.footer-nav { display: flex; gap: 20px; font-size: .9rem; color: var(--ink-soft); }
.footer-nav a:hover { color: var(--brand); }
.copyright { margin: 0; font-size: .85rem; color: var(--ink-soft); }

/* 备案号：分别跳转公安备案与工信部备案系统 */
.copyright .beian {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  margin-left: 10px;
  transition: color .2s;
}

.copyright .beian:hover { color: var(--brand); text-decoration: underline; }
.copyright .beian img { width: 16px; height: 16px; }

/* 滚动进场动画，由 JS 添加 .is-visible */
.reveal {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity .6s ease, transform .6s ease;
}

.reveal.is-visible { opacity: 1; transform: none; }

@media (prefers-reduced-motion: reduce) {
  .reveal { opacity: 1; transform: none; transition: none; }
  html { scroll-behavior: auto; }
}

/* 响应式 */
@media (max-width: 1024px) {
  .grid-3 { grid-template-columns: repeat(2, 1fr); }
  .tech-groups { grid-template-columns: 1fr; }
}

@media (max-width: 860px) {
  .nav {
    position: absolute;
    top: 68px;
    left: 0;
    right: 0;
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 12px 24px 20px;
    background: #fff;
    border-bottom: 1px solid var(--line);
    box-shadow: var(--shadow);
  }

  .nav.is-open { display: flex; }
  .nav a { padding: 12px 0; }
  .nav .nav-cta { margin-top: 10px; text-align: center; }
  .nav-toggle { display: block; }

  .hero { padding: 56px 0 48px; }
  .hero-inner,
  .about-inner,
  .contact-card { grid-template-columns: 1fr; gap: 32px; }

  .section { padding: 56px 0; }
  .product { grid-template-columns: 1fr; gap: 26px; padding: 24px; }
  .contact-card { padding: 32px 24px; }
  .footer-inner { flex-direction: column; align-items: flex-start; }
}

@media (max-width: 560px) {
  .grid-3 { grid-template-columns: 1fr; }
  .hero-stats { gap: 20px; }
  .contact-list li { flex-direction: column; gap: 2px; }
  .contact-value { text-align: left; }
}