:root{--header-offset:122px;--primary-color:#E53935;--secondary-color:#FF5A4F;--text-main:#333333;--card-bg:#FFFFFF;--bg-main:#F5F7FA;--border-color:#E0E0E0;--btn-gradient:linear-gradient(180deg,#FF5A4F 0%,#E53935 100%)}body{padding-top:var(--header-offset);margin:0;font-family:'Segoe UI',Tahoma,Geneva,Verdana,sans-serif;background-color:var(--bg-main);color:var(--text-main);overflow-x:hidden}.site-header{position:fixed;top:0;left:0;width:100%;z-index:1000;background-color:#FFFFFF;box-shadow:0 2px 10px rgba(0,0,0,0.1);min-height:auto}.header-top{background-color:#FFFFFF;width:100%;border-bottom:1px solid var(--border-color)}.header-container{max-width:1200px;margin:0 auto;display:flex;justify-content:space-between;align-items:center;padding:0 24px;min-height:68px}.logo{font-size:1.4rem;font-weight:800;color:var(--primary-color);text-decoration:none;white-space:nowrap;letter-spacing:-0.5px;transition:color 0.2s ease;display:inline-block}.logo:hover{color:var(--secondary-color)}.desktop-nav-buttons{display:flex;align-items:center;gap:10px}.btn{display:inline-block;text-decoration:none;padding:10px 24px;border-radius:6px;font-weight:700;font-size:0.95rem;transition:all 0.3s ease;text-align:center;white-space:nowrap}.btn-register{background:var(--btn-gradient);color:#FFFFFF;box-shadow:0 4px 12px rgba(229,57,53,0.3);border:1px solid rgba(255,255,255,0.15)}.btn-register:hover{transform:translateY(-2px);box-shadow:0 6px 16px rgba(229,57,53,0.4)}.btn-login{background:#FFFFFF;color:var(--primary-color);border:2px solid var(--primary-color);box-shadow:0 4px 12px rgba(229,57,53,0.1)}.btn-login:hover{background:var(--primary-color);color:#FFFFFF;transform:translateY(-2px)}.main-nav{background-color:var(--primary-color);width:100%;display:flex;transition:all 0.3s ease}.nav-container{max-width:1200px;margin:0 auto;display:flex;flex-direction:row;justify-content:center;align-items:center;padding:10px 20px;flex-wrap:nowrap;width:100%}.nav-link{color:#FFFFFF;text-decoration:none;padding:8px 14px;margin:0 4px;font-weight:500;font-size:0.92rem;border-radius:4px;transition:all 0.3s ease;white-space:nowrap;text-transform:uppercase;letter-spacing:0.3px}.nav-link:hover{background-color:rgba(255,255,255,0.2);transform:translateY(-1px)}.mobile-nav-buttons{display:none}@media(max-width:768px){:root{--header-offset:146px}.page-content img{max-width:100%!important;height:auto!important;display:block}.page-content{overflow-x:hidden;max-width:100%}body{overflow-x:hidden}.site-header{background-color:#FFFFFF}.header-top{position:relative;z-index:1001;border-bottom:none}.header-container{width:100%;max-width:none;padding:0 15px;min-height:60px;justify-content:center;position:relative}.desktop-nav-buttons{display:none}.logo{font-size:1.1rem;text-align:center;flex:1}.main-nav{display:none;font-size:32px;position:fixed;top:0;left:0;width:85%;max-width:340px;height:100vh;background-color:#FFFFFF;flex-direction:column;justify-content:flex-start;align-items:stretch;padding-top:70px;box-shadow:4px 0 20px rgba(0,0,0,0.15);transform:translateX(-100%);overflow-y:auto;overflow-x:hidden;z-index:1000}.main-nav.active{display:flex;transform:translateX(0)}.nav-container{flex-direction:column;align-items:stretch;padding:0;width:100%;max-width:none}.nav-link{color:var(--primary-color);padding:14px 20px;font-size:0.95rem;border-bottom:1px solid #E8E8E8;margin:0;border-radius:0;text-align:left;text-transform:none;letter-spacing:normal}.nav-link:hover{background-color:#FFF5F5;transform:none}.mobile-nav-buttons{display:flex;position:fixed;top:60px;left:0;width:100%;background-color:#FFFFFF;padding:6px 15px;gap:10px;z-index:1000;border-bottom:1px solid var(--border-color);justify-content:center}.mobile-nav-buttons .btn{flex-shrink:0;padding:8px 20px;font-size:0.95rem}.mobile-menu-overlay{display:none;position:fixed;top:0;left:0;width:100%;height:100%;background-color:rgba(0,0,0,0.6);z-index:999;opacity:0;transition:opacity 0.3s ease}.mobile-menu-overlay.active{display:block;opacity:1}.hamburger-menu{display:block;position:absolute;left:15px;top:14px;width:32px;height:32px;background:transparent;border:none;cursor:pointer;z-index:1002;padding:4px;border-radius:4px}.hamburger-menu span{display:block;width:24px;height:2.5px;margin:5px auto;background-color:var(--primary-color);transition:transform 0.3s ease,opacity 0.3s ease;border-radius:2px}.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)}}@media(min-width:769px){.hamburger-menu{display:none}.mobile-nav-buttons{display:none}.mobile-menu-overlay{display:none!important}}
/* 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;
}