.site-header{position:fixed;top:0;left:0;width:100%;z-index:1000;background:#fff;box-shadow:0 2px 12px rgba(31,45,61,0.08);font-family:Arial,sans-serif}.header-top{background:linear-gradient(135deg,#1a3a8f,#2F6BFF);width:100%;color:#fff}.header-container{max-width:1200px;margin:0 auto;display:flex;justify-content:space-between;align-items:center;padding:0 20px;padding-left:30px;padding-right:30px;box-sizing:border-box}.logo{font-size:32px;font-weight:900;color:#ffffff;text-decoration:none;letter-spacing:1px;display:block;text-shadow:0 2px 4px rgba(0,0,0,0.25);font-style:italic}.desktop-nav-buttons{display:flex;gap:10px;margin:0;padding:8px 0;align-items:center}.btn{display:inline-block;padding:9px 20px;font-size:14px;font-weight:700;text-decoration:none;border-radius:6px;transition:all 0.3s ease;border:none;text-align:center}.btn-register{background:linear-gradient(135deg,#ff6b6b,#e63946);color:#fff;box-shadow:0 2px 8px rgba(230,57,70,0.3)}.btn-login{background:linear-gradient(180deg,#4A8BFF 0%,#2F6BFF 100%);color:#fff;border:2px solid #fff;box-shadow:0 2px 8px rgba(47,107,255,0.2)}.btn:hover{transform:translateY(-2px);box-shadow:0 6px 16px rgba(0,0,0,0.15);opacity:0.9}.main-nav{background:#F4F7FB;width:100%;display:flex;position:static;box-shadow:none}.nav-container{max-width:1200px;margin:0 auto;display:flex;flex-direction:row;justify-content:center;align-items:center;padding:0 20px;box-sizing:border-box;gap:0;width:auto}.nav-link{display:inline-block;padding:13px 18px;font-size:15px;color:#1F2D3D;text-decoration:none;transition:color 0.3s ease,background 0.3s ease;border-right:1px solid #D6E2FF}.nav-link:first-child{border-left:none}.nav-link:hover,.nav-link.active{background:#E8F0FF;color:#2F6BFF}.mobile-nav-buttons{display:none}.hamburger-menu{display:none}.mobile-menu-overlay{display:none}body{padding-top:120px}.page-content img{max-width:100%;height:auto;display:block}.page-content{overflow-x:hidden;max-width:100%}body{overflow-x:hidden}@media(max-width:768px){:root{--header-offset:108px}.header-top{background:linear-gradient(135deg,#1a3a8f,#2F6BFF)}.header-container{width:100%;max-width:none;padding-left:15px;padding-right:15px}.logo{font-size:26px;order:2;flex:1;text-align:center;margin:0;padding:8px 0}.hamburger-menu{display:flex;flex-direction:column;justify-content:center;align-items:center;cursor:pointer;padding:10px;width:44px;height:44px;z-index:1002;order:1;background:transparent}.hamburger-menu span{width:22px;height:2px;background:#fff;margin:3px 0;display:block;transition:all 0.3s ease}.hamburger-menu.active span:nth-child(1){transform:rotate(45deg) translateY(8px)}.hamburger-menu.active span:nth-child(2){opacity:0}.hamburger-menu.active span:nth-child(3){transform:rotate(-45deg) translateY(-8px)}.desktop-nav-buttons{display:none}.main-nav{display:none;flex-direction:column;position:fixed;top:0;right:auto;left:0;width:80%;height:100vh;background:#fff;z-index:1001;transform:translateX(-100%);transition:transform 0.3s ease,display 0.3s ease;box-shadow:0 2px 12px rgba(0,0,0,0.1);overflow-y:auto}.main-nav.active{display:block;transform:translateX(0)}.nav-container{flex-direction:column;align-items:flex-start;justify-content:flex-start;width:100%;max-width:none;padding:20px 15px;text-align:left}.nav-link{width:100%;padding:12px 10px;border-bottom:1px solid #F4F7FB;border-right:none;color:#1F2D3D}.nav-link:hover,.nav-link.active{background:#F4F7FB;color:#2F6BFF}.mobile-nav-buttons{display:block;width:100%;background:#F4F7FB;border-top:1px solid #D6E2FF;padding:10px 0;z-index:1000}.mobile-nav-buttons .header-container{width:100%;max-width:none;padding-left:15px;padding-right:15px;display:flex;justify-content:center;gap:10px}.mobile-nav-buttons .btn{font-size:13px;padding:8px 15px}.mobile-menu-overlay{position:fixed;top:0;left:0;width:100%;height:100%;background:rgba(0,0,0,0.5);z-index:999;opacity:0;visibility:hidden;transition:opacity 0.3s ease}.mobile-menu-overlay.active{opacity:1;visibility:visible}.header-top{padding:0}.header-container>*{margin:0 2px}.mobile-nav-buttons .header-container>*{flex:1}.page-content img{max-width:100%!important;height:auto!important;display:block}.page-content{overflow-x:hidden;max-width:100%;width:100%}body{overflow-x:hidden;padding-top:108px}}
/* 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;
}