:root { --header-offset: 122px; --primary: #2F6BFF; --secondary: #6FA3FF; --btn-gradient: linear-gradient(180deg, #4A8BFF 0%, #2F6BFF 100%); --text-main: #1F2D3D; --bg-light: #F4F7FB; --card-bg: #FFFFFF; --border: #D6E2FF; --glow: #A5C4FF; }
body { padding-top: var(--header-offset); margin: 0; font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif; overflow-x: hidden; }
.site-header { position: fixed; top: 0; left: 0; width: 100%; z-index: 1000; box-shadow: 0 4px 20px rgba(31, 45, 61, 0.12); background: var(--card-bg); }
.header-top { background: var(--card-bg); border-bottom: 1px solid var(--border); width: 100%; }
.header-container { max-width: 1200px; margin: 0 auto; display: flex; justify-content: space-between; align-items: center; padding: 12px 30px; min-height: 68px; box-sizing: border-box; }
.logo { font-size: 32px; font-weight: 900; color: var(--primary); text-decoration: none; letter-spacing: -0.5px; font-family: 'Inter', sans-serif; display: inline-block; line-height: 1.2; }
.logo:hover { color: var(--primary); opacity: 0.9; }
.desktop-nav-buttons { display: flex; gap: 12px; align-items: center; }
.btn { display: inline-flex; align-items: center; justify-content: center; padding: 10px 26px; border-radius: 50px; font-size: 15px; font-weight: 700; text-decoration: none; transition: all 0.3s ease; border: none; cursor: pointer; letter-spacing: 0.2px; box-shadow: 0 4px 12px rgba(47, 107, 255, 0.25); }
.btn:hover { transform: translateY(-2px); box-shadow: 0 8px 24px rgba(47, 107, 255, 0.35); }
.btn-register { background: var(--btn-gradient); color: #FFFFFF; }
.btn-download { background: #FFFFFF; color: var(--primary); border: 2px solid var(--primary); box-shadow: none; }
.btn-download:hover { background: var(--bg-light); box-shadow: 0 4px 12px rgba(47, 107, 255, 0.15); }
.main-nav { background: var(--card-bg); border-top: 1px solid var(--border); border-bottom: 1px solid var(--border); display: flex; width: 100%; }
.nav-container { max-width: 1200px; margin: 0 auto; display: flex; flex-direction: row; justify-content: center; align-items: center; padding: 10px 30px; box-sizing: border-box; gap: 24px; }
.nav-link { color: var(--text-main); text-decoration: none; font-size: 15px; font-weight: 600; padding: 8px 4px; position: relative; transition: color 0.3s ease; white-space: nowrap; }
.nav-link:after { content: ''; position: absolute; bottom: 0; left: 0; width: 0; height: 2px; background: var(--primary); transition: width 0.3s ease; }
.nav-link:hover { color: var(--primary); }
.nav-link:hover:after { width: 100%; }
.mobile-nav-buttons { display: none; }
.hamburger-menu { display: none; }
.mobile-menu-overlay { display: none; }
.site-footer { background: var(--text-main); color: #FFFFFF; padding: 60px 20px 0; font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif; }
.footer-container { max-width: 1200px; margin: 0 auto; display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 40px; padding-bottom: 50px; border-bottom: 1px solid rgba(255, 255, 255, 0.1); }
.footer-logo { font-size: 32px; font-weight: 900; color: #FFFFFF; text-decoration: none; letter-spacing: -0.5px; display: inline-block; margin-bottom: 20px; }
.footer-desc { font-size: 14px; line-height: 1.8; color: rgba(255, 255, 255, 0.7); margin-bottom: 16px; max-width: 320px; }
.footer-license { font-size: 13px; line-height: 1.6; color: rgba(255, 255, 255, 0.5); }
.footer-title { font-size: 18px; font-weight: 700; color: #FFFFFF; margin-bottom: 24px; position: relative; padding-bottom: 12px; }
.footer-title:after { content: ''; position: absolute; bottom: 0; left: 0; width: 40px; height: 2px; background: var(--primary); }
.footer-nav { list-style: none; padding: 0; margin: 0; display: flex; flex-direction: column; gap: 14px; }
.footer-nav li a { color: rgba(255, 255, 255, 0.7); text-decoration: none; font-size: 15px; transition: all 0.3s ease; line-height: 1.5; }
.footer-nav li a:hover { color: #FFFFFF; padding-left: 6px; }
.footer-contact { list-style: none; padding: 0; margin: 0; display: flex; flex-direction: column; gap: 14px; }
.footer-contact li { color: rgba(255, 255, 255, 0.7); font-size: 15px; line-height: 1.6; }
.footer-bottom { text-align: center; padding: 24px 0; }
.copyright { font-size: 14px; color: rgba(255, 255, 255, 0.5); margin: 0; }
@media (max-width: 768px) {
  :root { --header-offset: 146px; }
  .header-container { width: 100%; max-width: none; padding: 10px 15px; min-height: 60px; }
  .header-top { border-bottom: 1px solid var(--border); }
  .logo { font-size: 28px; }
  .desktop-nav-buttons { display: none; }
  .main-nav { display: none; position: fixed; top: 0; right: 0; width: 78%; max-width: 360px; height: 100vh; flex-direction: column; background: var(--card-bg); z-index: 1002; transform: translateX(100%); transition: transform 0.35s ease; padding-top: 80px; border-left: 1px solid var(--border); box-shadow: -8px 0 30px rgba(0, 0, 0, 0.15); }
  .main-nav.active { display: block; transform: translateX(0); }
  .nav-container { flex-direction: column; justify-content: flex-start; align-items: flex-start; width: 100%; max-width: none; padding: 10px 20px; gap: 0; height: auto; }
  .nav-link { width: 100%; padding: 14px 0; font-size: 16px; border-bottom: 1px solid var(--border); }
  .nav-link:after { display: none; }
  .hamburger-menu { display: flex; flex-direction: column; justify-content: center; align-items: center; width: 44px; height: 44px; background: transparent; border: none; cursor: pointer; padding: 10px; gap: 5px; z-index: 1003; position: fixed; top: 9px; left: 10px; }
  .hamburger-menu span { display: block; width: 24px; height: 2.5px; background: var(--primary); border-radius: 3px; transition: all 0.3s ease; }
  .hamburger-menu.active span:nth-child(1) { transform: translateY(7.5px) rotate(45deg); }
  .hamburger-menu.active span:nth-child(2) { opacity: 0; }
  .hamburger-menu.active span:nth-child(3) { transform: translateY(-7.5px) rotate(-45deg); }
  .mobile-menu-overlay { display: none; position: fixed; inset: 0; background: rgba(0, 0, 0, 0.6); z-index: 1001; transition: opacity 0.35s ease; opacity: 0; }
  .mobile-menu-overlay.active { display: block; opacity: 1; }
  .mobile-nav-buttons { display: flex; width: 100%; background: var(--card-bg); border-top: 1px solid var(--border); justify-content: center; align-items: center; gap: 12px; padding: 10px 15px; position: fixed; top: 0; left: 0; z-index: 999; transform: none; }
  .btn { padding: 8px 20px; font-size: 14px; }
  .site-footer { padding: 40px 15px 10px; }
  .footer-container { grid-template-columns: 1fr; gap: 30px; padding-bottom: 30px; }
  .footer-logo { font-size: 28px; }
  .footer-bottom { padding: 16px 0; }
  .page-content img { display: block; height: auto !important; max-width: 100% !important; }
  .page-content { max-width: 100%; overflow-x: hidden; }
  body { overflow-x: hidden; }
}
/* 移动端内容区防溢出（系统追加，请勿删除） */
@media (max-width: 768px) {
  .page-content img {
    max-width: 100% !important;
    height: auto !important;
    display: block;
  }
  .page-content {
    overflow-x: hidden;
    max-width: 100%;
  }
  body {
    overflow-x: hidden;
  }
}
/* 内容保护（系统追加，请勿删除） */
body {
  -webkit-user-select: none;
  -moz-user-select: none;
  -ms-user-select: none;
  user-select: none;
}
input, textarea, select, [contenteditable="true"] {
  -webkit-user-select: text;
  -moz-user-select: text;
  user-select: text;
}