/* ==================== 重置与基础 ==================== */
* { padding: 0; margin: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  color: #181818;
  background: #fff;
  min-width: 320px;
  overflow-x: hidden;
}
li { list-style: none; }
a { text-decoration: none; color: inherit; }
img { max-width: 100%; display: block; }

/* ==================== 变量 ==================== */
:root {
  --primary: #336DF4;
  --primary-light: #EEF2FF;
  --text-main: #181818;
  --text-desc: #6B738F;
  --footer-bg: #1A1D26;
  --max-width: 1400px;
  --header-height: 72px;
}

/* ==================== 容器 ==================== */
.container { max-width: var(--max-width); margin: 0 auto; }
.container-wide { max-width: 100%; }

/* ==================== 头部导航 ==================== */
.header {
  position: fixed; top: 0; left: 0; width: 100%; height: var(--header-height);
  background: rgba(255,255,255,0.97); backdrop-filter: blur(10px);
  z-index: 9999; box-shadow: 0 1px 4px rgba(0,0,0,0.06);
  transition: all 0.3s;
}
.header-inner {
  max-width: var(--max-width); margin: 0 auto;
  display: flex; align-items: center; justify-content: space-between; height: 100%;
}
.header-logo { display: flex; align-items: center; gap: 10px; flex-shrink: 0; }
.header-logo img { height: 36px; width: auto; }
.header-logo span { font-size: 20px; font-weight: 700; color: var(--text-main); }
#main-nav { display: flex; align-items: center; gap: 0; }
#main-nav a { display: flex; align-items: center; }
.nav-li {
  padding: 0 20px; line-height: var(--header-height); font-size: 15px;
  color: var(--text-main); cursor: pointer; position: relative; transition: color 0.3s;
}
.nav-li:hover { color: var(--primary); }
.nav-li.active { color: var(--primary); font-weight: 600; }
.nav-li.active::after {
  content: ''; position: absolute; bottom: 0; left: 20px; right: 20px;
  height: 3px; background: var(--primary); border-radius: 2px;
}
.header-right { display: flex; align-items: center; gap: 16px; flex-shrink: 0; }
#lang-toggle {
  padding: 6px 16px; border: 1px solid #ddd; border-radius: 20px;
  font-size: 14px; cursor: pointer; background: transparent; color: var(--text-main);
  transition: all 0.3s;
}
#lang-toggle:hover { border-color: var(--primary); color: var(--primary); }
#lang-toggle .lang-active { color: var(--primary); font-weight: 700; }
.btn-business {
  padding: 8px 24px; background: var(--primary); color: #fff; border: none;
  border-radius: 24px; font-size: 14px; cursor: pointer; transition: all 0.3s;
}
.btn-business:hover { background: #2558d4; transform: translateY(-1px); }

/* 移动端汉堡菜单 */
.hamburger { display: none; flex-direction: column; gap: 5px; cursor: pointer; padding: 8px; }
.hamburger span { width: 24px; height: 2px; background: var(--text-main); transition: all 0.3s; }

/* ==================== 页面 Banner ==================== */
.page-banner {
  position: relative; width: 100%; height: 320px;
  display: flex; align-items: center; justify-content: center;
  overflow: hidden; margin-top: var(--header-height);
}
.page-banner .banner-bg {
  position: absolute; inset: 0; width: 100%; height: 100%;
  object-fit: cover;
}
.page-banner .banner-overlay {
  position: absolute; inset: 0;
  background: linear-gradient(135deg, rgba(51,109,244,0.3), rgba(26,29,38,0.5));
}
.page-banner .banner-content {
  position: relative; z-index: 2; text-align: center; color: #fff;
}
.page-banner .banner-content h1 { font-size: 42px; font-weight: 700; margin-bottom: 16px; }
.page-banner .banner-content p { font-size: 16px; opacity: 0.9; max-width: 700px; margin: 0 auto; line-height: 1.6; }

/* ==================== 页脚 ==================== */
.footer {
  background: var(--footer-bg); color: #fff; padding: 60px 0 0;
}
.footer-inner {
  max-width: var(--max-width); margin: 0 auto;
  display: grid; grid-template-columns: 1.5fr 1fr 1fr 1.2fr; gap: 40px;
}
.footer-brand img#footer-brand-name { height: 36px; margin-bottom: 8px; }
.footer-brand .slogan { font-size: 13px; color: #ffffff; margin-bottom: 16px; }
.footer-brand .desc { font-size: 13px; color: #ffffff; line-height: 1.8; }
.footer-col h4 { font-size: 16px; font-weight: 600; margin-bottom: 20px; }
.footer-col ul li { margin-bottom: 12px; }
.footer-col ul li a { font-size: 14px; color: #ffffff; transition: color 0.3s; }
.footer-col ul li a:hover { color: var(--primary); }
.footer-contact p { font-size: 14px; color: #ffffff; margin-bottom: 10px; line-height: 1.6; }
.footer-bottom {
  max-width: var(--max-width); margin: 40px auto 0; padding: 20px 0;
  border-top: 1px solid rgba(255,255,255,0.08);
  display: flex; justify-content: space-between; align-items: center;
  font-size: 13px; color: #6B738F;
}

/* ==================== 通用 Section ==================== */
.section { padding: 80px 0; }
.section-light { background: var(--primary-light); }
.section-title { text-align: center; margin-bottom: 50px; }
.section-title h2 { font-size: 32px; font-weight: 700; color: var(--text-main); margin-bottom: 12px; }
.section-title p { font-size: 15px; color: var(--text-desc); }

/* ==================== 按钮 ==================== */
.btn-primary {
  display: inline-block; padding: 12px 32px; background: var(--primary); color: #fff;
  border: none; border-radius: 8px; font-size: 15px; cursor: pointer;
  transition: all 0.3s; text-decoration: none;
}
.btn-primary:hover { background: #2558d4; transform: translateY(-2px); box-shadow: 0 4px 12px rgba(51,109,244,0.3); }
.btn-outline {
  display: inline-block; padding: 12px 32px; background: transparent; color: #fff;
  border: 2px solid #fff; border-radius: 8px; font-size: 15px; cursor: pointer;
  transition: all 0.3s; text-decoration: none;
}
.btn-outline:hover { background: #fff; color: var(--primary); }

/* ==================== 响应式 ==================== */
@media (max-width: 1400px) {
  .container { padding: 0 40px; }
  .header-inner { padding: 0 40px; }
  .footer-inner { padding: 0 40px; }
}

@media (max-width: 1200px) {
  .container { padding: 0 24px; }
  .header-inner { padding: 0 24px; }
  .footer-inner { padding: 0 24px; }
  .footer-bottom { padding: 20px 24px; }
}

@media (max-width: 992px) {
  .nav-li { padding: 0 12px; font-size: 14px; }
  .footer-inner { grid-template-columns: 1fr 1fr; gap: 30px; }
  .page-banner { height: 260px; }
  .page-banner .banner-content h1 { font-size: 32px; }
}

@media (max-width: 768px) {
  :root { --header-height: 60px; }
  .hamburger { display: flex; }
  #main-nav {
    display: none; position: fixed; top: var(--header-height); left: 0; right: 0;
    background: #fff; flex-direction: column; box-shadow: 0 4px 12px rgba(0,0,0,0.1);
    z-index: 9998;
  }
  #main-nav.open { display: flex; }
  .nav-li { line-height: 48px; width: 100%; text-align: center; }
  .nav-li.active::after { left: 50%; transform: translateX(-50%); width: 40px; }
  .header-right .btn-business { display: none; }
  .page-banner { height: 220px; }
  .page-banner .banner-content h1 { font-size: 26px; }
  .page-banner .banner-content p { font-size: 14px; padding: 0 20px; }
  .section { padding: 50px 0; }
  .section-title h2 { font-size: 24px; }
  .footer-inner { grid-template-columns: 1fr; gap: 24px; }
  .footer-bottom { flex-direction: column; gap: 8px; text-align: center; }
}

@media (max-width: 480px) {
  .page-banner { height: 180px; }
  .page-banner .banner-content h1 { font-size: 22px; }
}


/* ==================== 页脚底部 ==================== */
.footer-bottom {
  max-width: var(--max-width); margin: 0 auto; padding: 20px 0;
  border-top: 1px solid rgba(255,255,255,0.08);
  display: flex; justify-content: space-between; align-items: center;
  font-size: 13px; color: #6B738F;
}
.footer-bottom span { margin: 0 8px; }

/* ==================== 联系表单容器 ==================== */
.contact-form-wrapper {
  display: flex; align-items: flex-start; justify-content: flex-end;
}
.contact-form {
  background: var(--primary-light); border-radius: 16px; padding: 40px 36px;
  width: 100%; max-width: 520px;
}

/* ==================== 联系信息项 ==================== */
.contact-items { display: flex; flex-direction: column; }
.contact-item {
  display: flex; align-items: center; gap: 16px; padding: 16px 0;
  border-bottom: 1px solid #F3F4F6;
}
.contact-item img { width: 40px; height: 40px; flex-shrink: 0; }
.contact-detail { display: flex; flex-direction: column; gap: 4px; }
.contact-label { font-size: 13px; color: var(--text-desc); }
.contact-value { font-size: 16px; font-weight: 600; color: var(--text-main); }

/* ==================== 通用 section padding ==================== */
.section { padding: 80px 0; }
.section-title { text-align: center; margin-bottom: 50px; }
.section-title h2 { font-size: 32px; font-weight: 700; color: var(--text-main); margin-bottom: 12px; }
.section-title p { font-size: 15px; color: var(--text-desc); }