/* 元鼎(北京)科技有限公司官网 - 公共样式 */

*, *::before, *::after { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
  font-family: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Helvetica, Arial, sans-serif;
  font-size: 14px;
  color: #4d5a6e;
  background: #fff;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}
img { max-width: 100%; display: inline-block; }
a { text-decoration: none; color: inherit; }
ul, ol { list-style: none; padding: 0; margin: 0; }
h1, h2, h3, h4, h5, h6 { margin: 0; font-weight: 600; color: #282f38; }
p { margin: 0; }
button { font-family: inherit; cursor: pointer; }

.container { max-width: 1200px; margin: 0 auto; padding: 0 20px; }

/* ===== 顶部导航 ===== */
.header {
  position: sticky; top: 0; z-index: 100;
  background: rgba(255, 255, 255, 0.96);
  backdrop-filter: saturate(180%) blur(8px);
  border-bottom: 1px solid #eef0f4;
}
.header-inner {
  max-width: 1200px; margin: 0 auto;
  display: flex; align-items: center; justify-content: space-between;
  height: 64px; padding: 0 20px;
}
.logo {
  display: flex; align-items: center; gap: 10px;
  font-size: 18px; font-weight: 600; color: #282f38;
}
.logo-mark {
  width: 34px; height: 34px;
  display: inline-flex; align-items: center; justify-content: center;
  background: linear-gradient(135deg, #3a6cf0, #1e3a9a);
  color: #fff; border-radius: 7px;
  font-weight: 700; font-size: 18px;
}
.nav { display: flex; gap: 36px; }
.nav a {
  font-size: 15px; color: #4d5a6e;
  position: relative; padding: 4px 0;
  transition: color 0.2s;
}
.nav a:hover, .nav a.active { color: #1e3a9a; }
.nav a.active::after {
  content: ""; position: absolute; left: 0; right: 0; bottom: -22px;
  height: 2px; background: #1e3a9a; border-radius: 2px;
}
.nav-cta {
  padding: 7px 18px; border-radius: 999px;
  background: transparent;
  color: #1e3a9a !important; font-size: 14px; font-weight: 500;
  border: 1px solid #c9d4f5;
  transition: all 0.2s;
}
.nav-cta:hover {
  background: #1e3a9a; color: #fff !important; border-color: #1e3a9a;
}

.mobile-toggle { display: none; background: none; border: 0; font-size: 22px; color: #4d5a6e; }

@media (max-width: 768px) {
  .nav { display: none; position: absolute; top: 64px; left: 0; right: 0;
         flex-direction: column; gap: 0; background: #fff;
         border-bottom: 1px solid #eef0f4; padding: 8px 0; }
  .nav.open { display: flex; }
  .nav a { padding: 12px 20px; }
  .nav a.active::after { display: none; }
  .nav-cta { margin: 8px 20px; text-align: center; }
  .mobile-toggle { display: block; }
}

/* ===== Banner ===== */
.banner {
  background: linear-gradient(180deg, #f0f4ff 0%, #ffffff 100%);
  padding: 80px 0 60px;
}
.banner-inner {
  max-width: 1200px; margin: 0 auto; padding: 0 20px;
  display: flex; align-items: center; gap: 60px;
}
.banner-content { flex: 1; }
.banner-eyebrow {
  display: inline-block;
  padding: 4px 12px; border-radius: 20px;
  background: #e3e9ff; color: #1e3a9a;
  font-size: 13px; font-weight: 500;
  margin-bottom: 20px;
}
.banner h1 {
  font-size: 44px; line-height: 1.3; color: #282f38;
  margin-bottom: 20px; letter-spacing: 0.5px;
}
.banner .lead {
  font-size: 17px; color: #4d5a6e; line-height: 1.8; margin-bottom: 32px;
}
.banner-ctas { display: flex; gap: 12px; flex-wrap: wrap; }
.btn {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 12px 28px; border-radius: 4px;
  font-size: 15px; font-weight: 500;
  transition: all 0.2s; border: 0;
}
.btn-primary {
  background: linear-gradient(135deg, #3a6cf0, #1e3a9a);
  color: #fff;
}
.btn-primary:hover { opacity: 0.92; transform: translateY(-1px); }
.btn-ghost {
  background: #fff; color: #1e3a9a;
  border: 1px solid #1e3a9a;
}
.btn-ghost:hover { background: #f0f4ff; }
.banner-visual {
  flex: 1; display: flex; justify-content: center; align-items: center;
  min-height: 320px;
}
.banner-visual .visual-card {
  width: 100%; max-width: 460px; aspect-ratio: 4/3;
  background: linear-gradient(135deg, #ffffff 0%, #e9efff 100%);
  border-radius: 16px; box-shadow: 0 20px 60px rgba(30, 58, 154, 0.18);
  display: flex; align-items: center; justify-content: center;
  position: relative; overflow: hidden;
}
.banner-visual .visual-card::before {
  content: "元"; font-size: 180px; font-weight: 700;
  background: linear-gradient(135deg, #3a6cf0, #1e3a9a);
  -webkit-background-clip: text; background-clip: text;
  -webkit-text-fill-color: transparent;
}
.banner-visual .visual-card::after {
  content: ""; position: absolute; right: -40px; top: -40px;
  width: 160px; height: 160px; border-radius: 50%;
  background: #e3e9ff;
}

@media (max-width: 900px) {
  .banner-inner { flex-direction: column; gap: 40px; text-align: center; }
  .banner h1 { font-size: 32px; }
  .banner-ctas { justify-content: center; }
  .banner-visual .visual-card { max-width: 300px; }
}

/* ===== 通用区段 ===== */
section { padding: 80px 0; }
.section-light { background: #f7f9fc; }
.section-title {
  text-align: center; margin-bottom: 56px;
}
.section-title .eyebrow {
  font-size: 14px; color: #1e3a9a; letter-spacing: 2px;
  text-transform: uppercase; margin-bottom: 12px;
}
.section-title h2 {
  font-size: 32px; color: #282f38; margin-bottom: 12px;
}
.section-title p { color: #7a8599; font-size: 16px; }

/* ===== 卡片网格 ===== */
.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.grid-4 { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.grid-2 { display: grid; grid-template-columns: repeat(2, 1fr); gap: 24px; }
@media (max-width: 900px) {
  .grid-3, .grid-4 { grid-template-columns: 1fr; }
  .grid-2 { grid-template-columns: 1fr; }
}
.card {
  background: #fff; border-radius: 10px; padding: 32px 28px;
  box-shadow: 0 2px 16px rgba(0, 0, 0, 0.04);
  border: 1px solid #eef0f4;
  transition: transform 0.2s, box-shadow 0.2s;
}
.card:hover { transform: translateY(-4px); box-shadow: 0 8px 30px rgba(30, 58, 154, 0.12); }
.card .icon {
  width: 48px; height: 48px; border-radius: 10px;
  background: #e3e9ff; color: #1e3a9a;
  display: flex; align-items: center; justify-content: center;
  font-size: 22px; font-weight: 700; margin-bottom: 20px;
}
.card h3 { font-size: 18px; color: #282f38; margin-bottom: 12px; }
.card p { color: #6e7480; font-size: 14px; line-height: 1.8; }
.card ul { margin-top: 12px; }
.card li {
  position: relative; padding-left: 18px;
  color: #6e7480; font-size: 14px; line-height: 2;
}
.card li::before {
  content: ""; position: absolute; left: 0; top: 13px;
  width: 6px; height: 6px; border-radius: 50%;
  background: #1e3a9a;
}

/* ===== 数据指标 ===== */
.metric {
  text-align: center; padding: 32px 20px;
  background: linear-gradient(180deg, #f0f4ff 0%, #ffffff 100%);
  border-radius: 10px;
}
.metric .num {
  font-size: 42px; font-weight: 700;
  background: linear-gradient(135deg, #3a6cf0, #1e3a9a);
  -webkit-background-clip: text; background-clip: text;
  -webkit-text-fill-color: transparent;
  line-height: 1.2;
}
.metric .label {
  font-size: 15px; color: #354052; margin-top: 8px; font-weight: 500;
}
.metric .desc { font-size: 13px; color: #7a8599; margin-top: 6px; }

/* ===== 关于页 / 时间线 ===== */
.about-grid {
  display: grid; grid-template-columns: 1fr 1fr; gap: 60px;
  align-items: center;
}
@media (max-width: 900px) { .about-grid { grid-template-columns: 1fr; } }
.about-grid h2 { font-size: 32px; margin-bottom: 20px; }
.about-grid p { color: #4d5a6e; line-height: 1.9; margin-bottom: 14px; }

.info-list { display: grid; grid-template-columns: 1fr 1fr; gap: 16px 32px; }
.info-item { padding: 14px 0; border-bottom: 1px solid #eef0f4; }
.info-item .k { color: #7a8599; font-size: 13px; margin-bottom: 4px; }
.info-item .v { color: #282f38; font-size: 15px; font-weight: 500; }

/* ===== 联系页 ===== */
.contact-grid {
  display: grid; grid-template-columns: 1fr; gap: 24px;
  align-items: start;
  max-width: 720px;
}
@media (max-width: 900px) { .contact-grid { grid-template-columns: 1fr; } }
.contact-card {
  background: #fff; border-radius: 12px; padding: 36px;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.05);
  border: 1px solid #eef0f4;
}
.contact-card h3 { font-size: 20px; margin-bottom: 24px; }
.contact-row {
  display: flex; gap: 16px; padding: 16px 0;
  border-bottom: 1px solid #eef0f4;
}
.contact-row:last-child { border-bottom: 0; }
.contact-row .ico {
  flex-shrink: 0; width: 40px; height: 40px; border-radius: 8px;
  background: #e3e9ff; color: #1e3a9a;
  display: flex; align-items: center; justify-content: center;
  font-weight: 700; font-size: 16px;
}
.contact-row .label { color: #7a8599; font-size: 13px; margin-bottom: 4px; }
.contact-row .value { color: #282f38; font-size: 15px; line-height: 1.6; }

/* ===== 产品 / 服务页 ===== */
.product-hero {
  background: linear-gradient(180deg, #f0f4ff 0%, #ffffff 100%);
  padding: 80px 0 60px; text-align: center;
}
.product-hero h1 { font-size: 38px; margin-bottom: 16px; }
.product-hero p { color: #4d5a6e; font-size: 16px; max-width: 720px; margin: 0 auto; }

.scope-section { padding: 60px 0; }
.scope-section + .scope-section { padding-top: 0; }
.scope-header {
  display: flex; align-items: center; gap: 16px; margin-bottom: 32px;
}
.scope-header .num {
  flex-shrink: 0; width: 56px; height: 56px; border-radius: 12px;
  background: linear-gradient(135deg, #3a6cf0, #1e3a9a);
  color: #fff; font-size: 22px; font-weight: 700;
  display: flex; align-items: center; justify-content: center;
}
.scope-header h2 { font-size: 24px; }
.scope-header p { color: #7a8599; font-size: 14px; margin-top: 4px; }

/* ===== 页脚 ===== */
.footer {
  background: #1a2236; color: #a8b0c0;
  padding: 60px 0 24px; margin-top: 0;
}
.footer-grid {
  display: grid; grid-template-columns: 1.4fr repeat(4, 1fr); gap: 40px;
  margin-bottom: 40px;
}
@media (max-width: 900px) { .footer-grid { grid-template-columns: 1fr 1fr; } }
@media (max-width: 600px) { .footer-grid { grid-template-columns: 1fr; } }
.footer-brand .logo { color: #fff; margin-bottom: 12px; }
.footer-brand p { color: #8a93a6; font-size: 13px; line-height: 1.8; }
.footer-col h4 { color: #fff; font-size: 15px; margin-bottom: 16px; font-weight: 500; }
.footer-col li { margin-bottom: 10px; }
.footer-col a { color: #a8b0c0; font-size: 13px; transition: color 0.2s; }
.footer-col a:hover { color: #fff; }
.footer-col .li-text { font-size: 13px; line-height: 1.9; }
.footer-bottom {
  border-top: 1px solid #2a3349; padding-top: 24px;
  display: flex; justify-content: space-between; align-items: center;
  font-size: 13px; color: #8a93a6; flex-wrap: wrap; gap: 12px;
}
.footer-bottom a { color: #8a93a6; }
.footer-bottom a:hover { color: #fff; }
.footer-bottom .links { display: flex; gap: 16px; }
.footer-bottom .links a { display: inline-flex; align-items: center; gap: 6px; }
.police-icon { width: 6px; height: 6px; vertical-align: middle; }

/* ===== 工具类 ===== */
.mt-12 { margin-top: 12px; } .mt-24 { margin-top: 24px; } .mt-32 { margin-top: 32px; }
.mb-12 { margin-bottom: 12px; } .mb-24 { margin-bottom: 24px; }
.text-center { text-align: center; }
.fade-in { animation: fadeIn 0.6s ease-out; }
@keyframes fadeIn { from { opacity: 0; transform: translateY(10px); } to { opacity: 1; transform: none; } }