/* ========== 基础 ========== */
:root {
  --primary: #0e5fd8;
  --primary-dark: #0a4aa8;
  --text: #2b3441;
  --text-light: #6b7686;
  --bg: #ffffff;
  --bg-alt: #f5f8fc;
  --border: #e4e9f0;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: "PingFang SC", "Microsoft YaHei", "Segoe UI", sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.7;
}

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

ul {
  list-style: none;
}

.container {
  width: min(1100px, 92%);
  margin: 0 auto;
}

/* ========== 顶部导航 ========== */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--border);
  transition: box-shadow 0.3s;
}

.header.scrolled {
  box-shadow: 0 2px 12px rgba(20, 40, 80, 0.08);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

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

.logo-mark {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border-radius: 10px;
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: #fff;
  font-size: 20px;
  font-weight: 700;
}

.logo-text {
  display: flex;
  flex-direction: column;
  line-height: 1.25;
}

.logo-text strong {
  font-size: 17px;
}

.logo-text small {
  font-size: 11px;
  color: var(--text-light);
  letter-spacing: 0.5px;
}

.nav {
  display: flex;
  gap: 28px;
}

.nav a {
  font-size: 15px;
  color: var(--text);
  transition: color 0.2s;
}

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

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 6px;
}

.nav-toggle span {
  width: 22px;
  height: 2px;
  background: var(--text);
  border-radius: 2px;
  transition: transform 0.3s, opacity 0.3s;
}

/* ========== 首屏 ========== */
.hero {
  display: flex;
  align-items: center;
  min-height: 640px;
  padding-top: 64px;
  background:
    radial-gradient(1000px 500px at 85% 10%, rgba(14, 95, 216, 0.12), transparent 60%),
    radial-gradient(800px 400px at 10% 90%, rgba(14, 95, 216, 0.08), transparent 60%),
    linear-gradient(180deg, #f8fbff 0%, #ffffff 100%);
}

.hero-content {
  max-width: 760px;
}

.hero-tag {
  display: inline-block;
  padding: 6px 14px;
  margin-bottom: 20px;
  border-radius: 999px;
  background: rgba(14, 95, 216, 0.08);
  color: var(--primary);
  font-size: 14px;
}

.hero h1 {
  font-size: clamp(30px, 5vw, 46px);
  line-height: 1.25;
  margin-bottom: 18px;
}

.hero-sub {
  font-size: 17px;
  color: var(--text-light);
  margin-bottom: 32px;
}

.hero-actions {
  display: flex;
  gap: 14px;
  flex-wrap: wrap;
}

.btn {
  display: inline-block;
  padding: 12px 30px;
  border-radius: 8px;
  font-size: 15px;
  transition: background 0.2s, color 0.2s, transform 0.2s;
}

.btn-primary {
  background: var(--primary);
  color: #fff;
}

.btn-primary:hover {
  background: var(--primary-dark);
  transform: translateY(-2px);
}

.btn-outline {
  border: 1px solid var(--primary);
  color: var(--primary);
}

.btn-outline:hover {
  background: rgba(14, 95, 216, 0.06);
}

/* ========== 通用 Section ========== */
.section {
  padding: 80px 0;
}

.section-alt {
  background: var(--bg-alt);
}

.section-head {
  text-align: center;
  margin-bottom: 48px;
}

.section-head h2 {
  font-size: 30px;
  margin-bottom: 6px;
}

.section-head p {
  font-size: 13px;
  letter-spacing: 3px;
  color: var(--text-light);
  text-transform: uppercase;
}

/* ========== 公司简介 ========== */
.about-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr;
  gap: 48px;
  align-items: center;
}

.about-text p {
  margin-bottom: 16px;
  color: var(--text-light);
}

.about-text strong {
  color: var(--primary);
}

.about-stats {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.stat {
  padding: 24px 16px;
  text-align: center;
  background: var(--bg-alt);
  border-radius: 12px;
  border: 1px solid var(--border);
}

.stat strong {
  display: block;
  font-size: 26px;
  color: var(--primary);
  margin-bottom: 4px;
}

.stat span {
  font-size: 13px;
  color: var(--text-light);
}

/* ========== 产品中心 ========== */
.product-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.card {
  background: #fff;
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 30px 26px;
  transition: transform 0.25s, box-shadow 0.25s;
}

.card:hover {
  transform: translateY(-6px);
  box-shadow: 0 14px 32px rgba(20, 40, 80, 0.1);
}

.card-icon {
  font-size: 34px;
  margin-bottom: 14px;
}

.card h3 {
  font-size: 19px;
  margin-bottom: 12px;
}

.card > p {
  font-size: 14.5px;
  color: var(--text-light);
  margin-bottom: 16px;
}

.card ul li {
  position: relative;
  padding-left: 18px;
  font-size: 14px;
  color: var(--text-light);
  margin-bottom: 6px;
}

.card ul li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.72em;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--primary);
}

.product-note {
  margin-top: 28px;
  text-align: center;
  font-size: 14px;
  color: var(--text-light);
}

.product-note a {
  color: var(--primary);
}

/* ========== 优势 ========== */
.grid-4 {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.feature {
  text-align: center;
  padding: 28px 18px;
  border-radius: 14px;
  border: 1px solid var(--border);
  transition: transform 0.25s, box-shadow 0.25s;
}

.feature:hover {
  transform: translateY(-4px);
  box-shadow: 0 10px 26px rgba(20, 40, 80, 0.08);
}

.feature-icon {
  font-size: 30px;
  margin-bottom: 12px;
}

.feature h3 {
  font-size: 17px;
  margin-bottom: 8px;
}

.feature p {
  font-size: 13.5px;
  color: var(--text-light);
}

/* ========== 联系我们 ========== */
.contact-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.contact-item {
  background: #fff;
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 28px 24px;
  text-align: center;
}

.contact-item h3 {
  font-size: 15px;
  color: var(--primary);
  margin-bottom: 8px;
}

.contact-item p {
  font-size: 15px;
  color: var(--text-light);
}

/* ========== 页脚 ========== */
.footer {
  background: #1c2430;
  color: #aab4c2;
  padding: 28px 0;
  font-size: 14px;
}

.footer-inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
  text-align: center;
}

.footer a:hover {
  color: #fff;
}

/* ========== 入场动画 ========== */
.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

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

/* ========== 响应式 ========== */
@media (max-width: 900px) {
  .about-grid {
    grid-template-columns: 1fr;
    gap: 32px;
  }

  .product-grid {
    grid-template-columns: 1fr;
  }

  .grid-4 {
    grid-template-columns: repeat(2, 1fr);
  }

  .contact-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 700px) {
  .nav {
    position: fixed;
    top: 64px;
    left: 0;
    right: 0;
    flex-direction: column;
    gap: 0;
    background: #fff;
    border-bottom: 1px solid var(--border);
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
  }

  .nav.open {
    max-height: 320px;
  }

  .nav a {
    padding: 14px 24px;
    border-top: 1px solid var(--border);
  }

  .nav-toggle {
    display: flex;
  }

  .nav-toggle.open span:nth-child(1) {
    transform: translateY(7px) rotate(45deg);
  }

  .nav-toggle.open span:nth-child(2) {
    opacity: 0;
  }

  .nav-toggle.open span:nth-child(3) {
    transform: translateY(-7px) rotate(-45deg);
  }

  .grid-4 {
    grid-template-columns: 1fr;
  }

  .hero {
    min-height: 560px;
  }
}