:root{--primary:#2F6BFF;--primary-light:#6FA3FF;--primary-dark:#1E4FD1;--bg:#F4F7FB;--card-bg:#FFFFFF;--text-main:#1F2D3D;--border:#D6E2FF;--glow:#A5C4FF;--btn-gradient:linear-gradient(180deg,#4A8BFF 0%,#2F6BFF 100%);--header-offset:122px;--header-top-height:68px;--header-nav-height:52px;--header-mobile-offset:110px;--header-mobile-top-height:60px;--header-mobile-nav-height:48px;--mobile-btn-height:48px;--max-width:1200px}.site-header{position:fixed;top:0;left:0;width:100%;z-index:1000;box-shadow:0 4px 20px rgba(31,45,61,0.15);font-family:'Segoe UI',Roboto,'Helvetica Neue',Arial,sans-serif;line-height:1.4;box-sizing:border-box}.site-header *,.site-header *::before,.site-header *::after{box-sizing:border-box}.header-top{background-color:#1E4FD1;width:100%;min-height:var(--header-top-height)}.header-container{max-width:var(--max-width);margin:0 auto;display:flex;justify-content:space-between;align-items:center;min-height:var(--header-top-height);padding:0 30px}.logo{display:inline-flex;align-items:center;text-decoration:none;color:#FFFFFF;flex-shrink:0}.logo-text{font-size:28px;font-weight:800;letter-spacing:1px;font-style:italic;text-shadow:0 2px 8px rgba(0,0,0,0.2)}.desktop-nav-buttons{display:flex;align-items:center;gap:10px;flex-shrink:0}.btn{display:inline-flex;justify-content:center;align-items:center;text-decoration:none;padding:10px 24px;border-radius:30px;font-weight:700;font-size:14px;line-height:1.2;transition:all 0.3s ease;box-shadow:0 4px 15px rgba(47,107,255,0.35);white-space:nowrap}.btn:hover{transform:translateY(-2px);box-shadow:0 6px 20px rgba(47,107,255,0.5)}.main-nav{background-color:#FFFFFF;width:100%;display:flex;min-height:var(--header-nav-height);border-bottom:3px solid #D6E2FF}.nav-container{max-width:var(--max-width);width:100%;margin:0 auto;display:flex;flex-direction:row;justify-content:center;align-items:center;min-height:var(--header-nav-height);padding:0 20px}.nav-link{position:relative;display:inline-block;text-decoration:none;color:var(--text-main);font-size:14px;font-weight:600;padding:12px 16px;transition:color 0.3s ease;white-space:nowrap}.nav-link::after{content:'';position:absolute;left:50%;bottom:4px;transform:translateX(-50%);width:0;height:3px;border-radius:2px;background:linear-gradient(90deg,#2F6BFF,#6FA3FF);transition:width 0.3s ease}.nav-link:hover{color:var(--primary)}.nav-link:hover::after{width:60%}.btn-register{background:var(--btn-gradient);color:#FFFFFF}.btn-login{background:linear-gradient(180deg,#FFA94B 0%,#FF7A00 100%);color:#FFFFFF;box-shadow:0 4px 15px rgba(255,122,0,0.3)}.btn-download{background:linear-gradient(180deg,#0CA678 0%,#087F5B 100%);color:#FFFFFF;box-shadow:0 4px 15px rgba(12,166,120,0.3)}.main-nav.active{display:flex}.mobile-nav-buttons{display:none}.hamburger-menu{display:none}.mobile-menu-overlay{display:none}body{padding-top:var(--header-offset)}@media(max-width:768px){:root{--header-offset:158px}.site-header{box-shadow:0 4px 15px rgba(31,45,61,0.1)}.header-top{width:100%;min-height:60px;border-bottom:1px solid rgba(255,255,255,0.15)}.header-top .header-container{width:100%;max-width:none;min-height:60px;padding:0 60px 0 60px;display:flex;justify-content:center;position:relative}.header-top .logo{margin:0 auto;display:block}.logo-text{font-size:24px}.desktop-nav-buttons{display:none}.main-nav{display:none;position:fixed;top:60px;left:0;width:280px;height:auto;max-height:calc(100vh - 108px);overflow-y:auto;background-color:#FFFFFF;flex-direction:column;justify-content:flex-start;align-items:stretch;transform:translateX(-100%);transition:transform 0.35s ease;z-index:1002;border-radius:0 12px 12px 0;box-shadow:4px 8px 30px rgba(0,0,0,0.15);min-height:auto}.main-nav.active{display:flex;transform:translateX(0)}.nav-container{width:100%;max-width:none;display:flex;flex-direction:column;justify-content:flex-start;align-items:stretch;gap:0;padding:10px 0}.nav-link{color:var(--text-main);display:block;width:100%;text-align:left;padding:16px 24px;font-size:16px;border-bottom:1px solid #E8EEF8}.nav-link:hover{background-color:#F4F7FB;color:var(--primary)}.nav-link:hover::after{display:none}.mobile-nav-buttons{display:block;width:100%;background-color:#1E4FD1;padding:8px 0;min-height:0;z-index:1001}.mobile-buttons-container{width:100%;max-width:none;display:flex;justify-content:center;align-items:center;gap:10px;padding:0 15px}.mobile-nav-buttons .btn{padding:10px 18px;font-size:13px;flex-shrink:1;min-width:0;margin:0}.mobile-nav-buttons .btn-register{padding:10px 20px}.mobile-nav-buttons .btn-login{padding:10px 20px}.mobile-nav-buttons .btn-download{padding:10px 18px}.hamburger-menu{display:flex;flex-direction:column;justify-content:center;align-items:center;width:44px;height:44px;cursor:pointer;background-color:rgba(255,255,255,0.15);border-radius:8px;padding:10px;position:absolute;top:50%!important;transform:translateY(-50%)!important;left:10px;z-index:1003;transition:background-color 0.3s ease;border:1px solid rgba(255,255,255,0.3)}.hamburger-menu span{display:block;width:22px;height:2px;background-color:#FFFFFF;border-radius:2px;margin:2px 0;transition:all 0.3s ease}.hamburger-menu.active{background-color:#FFFFFF;border-color:#2F6BFF}.hamburger-menu.active span{background-color:#2F6BFF}.hamburger-menu.active span:nth-child(1){transform:rotate(45deg) translate(4px,4px)}.hamburger-menu.active span:nth-child(2){opacity:0}.hamburger-menu.active span:nth-child(3){transform:rotate(-45deg) translate(4px,-4px)}.mobile-menu-overlay{display:none;position:fixed;top:0;left:0;width:100%;height:100%;background-color:rgba(0,0,0,0.5);z-index:998}.mobile-menu-overlay.active{display:block}.page-content img{max-width:100%!important;height:auto!important;display:block}.page-content{overflow-x:hidden;max-width:100%}body{overflow-x:hidden;padding-top:var(--header-offset)}}
/* 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;
}