:root {
  --primary: #26A9E0;
  --primary-dark: #1A7FAD;
  --primary-light: #E1F4FC;
  --accent: #EA7C07;
  --dark: #000000;
  --white: #FFFFFF;
  --text-dark: #222222;
  --text-light: #FFFFFF;
  --header-offset: 122px;
  --header-offset-mobile: 160px;
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.15);
  --shadow-md: 0 4px 20px rgba(0, 0, 0, 0.12);
}

.site-header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  background: var(--white);
  box-shadow: var(--shadow-md);
  z-index: 1000;
  border-bottom: 1px solid rgba(0, 0, 0, 0.05);
}

.header-top {
  background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
  width: 100%;
}

.header-container {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 10px 24px;
  min-height: 68px;
}

.logo {
  display: inline-block;
  color: var(--text-light);
  font-size: 28px;
  font-weight: 800;
  text-decoration: none;
  letter-spacing: 0.5px;
  text-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
  line-height: 1.2;
}

.logo:hover {
  color: var(--accent);
}

.desktop-nav-buttons {
  display: flex;
  align-items: center;
  gap: 10px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 10px 22px;
  border-radius: 6px;
  font-weight: 700;
  font-size: 14px;
  text-decoration: none;
  transition: all 0.3s ease;
  border: none;
  cursor: pointer;
  box-shadow: 0 3px 8px rgba(0, 0, 0, 0.15);
}

.btn-login {
  background: var(--accent);
  color: var(--text-light);
}

.btn-login:hover {
  background: #D47206;
  transform: translateY(-2px);
  box-shadow: 0 6px 14px rgba(234, 124, 7, 0.35);
}

.btn-register {
  background: var(--white);
  color: var(--primary);
}

.btn-register:hover {
  background: var(--primary-light);
  transform: translateY(-2px);
  box-shadow: 0 6px 14px rgba(255, 255, 255, 0.2);
}

.main-nav {
  background: var(--white);
  width: 100%;
  display: flex;
  flex-direction: row;
  border-top: 1px solid rgba(0, 0, 0, 0.05);
  min-height: 52px;
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  flex-direction: row;
  justify-content: center;
  align-items: center;
  gap: 4px;
  padding: 6px 16px;
  width: 100%;
  flex-wrap: wrap;
}

.nav-link {
  color: var(--text-dark);
  font-size: 14px;
  font-weight: 600;
  text-decoration: none;
  padding: 8px 12px;
  border-radius: 4px;
  transition: all 0.2s ease;
  white-space: nowrap;
}

.nav-link:hover,
.nav-link.active {
  color: var(--primary);
  background: var(--primary-light);
}

.hamburger-menu,
.mobile-nav-buttons,
.mobile-menu-overlay {
  display: none;
}

.site-footer {
  background: #eaf6fc;
  border-top: 3px solid var(--primary);
  padding: 40px 0 0;
  margin-top: 40px;
}

.footer-container {
  max-width: 1200px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 30px;
  padding: 0 24px;
}

.footer-logo {
  display: inline-block;
  color: var(--primary);
  font-size: 26px;
  font-weight: 800;
  text-decoration: none;
  margin-bottom: 12px;
  letter-spacing: 0.5px;
}

.footer-desc {
  color: #4b5563;
  font-size: 14px;
  line-height: 1.6;
  max-width: 360px;
}

.footer-title {
  color: var(--primary);
  font-size: 16px;
  font-weight: 700;
  margin-bottom: 16px;
  padding-bottom: 8px;
  border-bottom: 2px solid rgba(38, 169, 224, 0.2);
}

.footer-nav {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px 16px;
  align-content: start;
}

.footer-nav a {
  color: #4b5563;
  font-size: 14px;
  text-decoration: none;
  padding: 3px 0;
  transition: all 0.2s ease;
}

.footer-nav a:hover {
  color: var(--primary);
  padding-left: 4px;
}

.footer-bottom {
  background: var(--primary);
  margin-top: 30px;
  padding: 14px 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px;
}

.footer-bottom p {
  color: var(--text-light);
  font-size: 13px;
  margin: 0;
}

.footer-18 {
  background: var(--accent);
  color: #fff;
  border-radius: 4px;
  padding: 2px 8px;
  font-weight: 700;
  font-size: 12px !important;
}

body {
  padding-top: var(--header-offset);
}

@media (max-width: 768px) {
  :root {
    --header-offset: 160px;
  }
  
  body {
    padding-top: var(--header-offset);
    overflow-x: hidden;
  }
  
  .header-top {
    min-height: 60px;
  }
  
  .header-container {
    width: 100%;
    max-width: none;
    padding: 8px 15px;
    min-height: 60px;
  }
  
  .logo {
    font-size: 22px;
    text-align: center;
    flex: 1;
    display: block;
    margin: 0 auto;
    order: 2;
    text-align: center;
  }
  
  .desktop-nav-buttons {
    display: none;
  }
  
  .hamburger-menu {
    display: flex;
    flex-direction: column;
    justify-content: center;
    gap: 5px;
    width: 44px;
    height: 44px;
    cursor: pointer;
    z-index: 1001;
    padding: 8px;
    background: transparent;
    border: none;
    order: 1;
  }
  
  .hamburger-menu span {
    display: block;
    width: 24px;
    height: 3px;
    background: var(--white);
    border-radius: 3px;
    transition: all 0.3s ease;
  }
  
  .hamburger-menu.active span:nth-child(1) {
    transform: translateY(8px) rotate(45deg);
  }
  
  .hamburger-menu.active span:nth-child(2) {
    opacity: 0;
  }
  
  .hamburger-menu.active span:nth-child(3) {
    transform: translateY(-8px) rotate(-45deg);
  }
  
  .mobile-nav-buttons {
    display: flex;
    justify-content: center;
    gap: 10px;
    padding: 8px 12px;
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
    min-height: 48px;
    z-index: 1000;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
  }
  
  .mobile-nav-buttons .btn {
    flex: 1;
    max-width: 180px;
    padding: 8px 16px;
    font-size: 13px;
  }
  
  .main-nav {
    display: none;
    flex-direction: column;
    position: fixed;
    top: 0;
    left: 0;
    width: 280px;
    height: 100vh;
    overflow-y: auto;
    background: var(--white);
    z-index: 1002;
    transform: translateX(-100%);
    transition: transform 0.3s ease;
    box-shadow: 4px 0 20px rgba(0, 0, 0, 0.15);
    min-height: 0;
    padding-top: 0;
    border-top: none;
  }
  
  .main-nav.active {
    display: block;
    transform: translateX(0);
  }
  
  .nav-container {
    width: 100%;
    max-width: none;
    flex-direction: column;
    justify-content: flex-start;
    align-items: stretch;
    padding: 20px 0;
    gap: 0;
  }
  
  .nav-link {
    padding: 14px 20px;
    font-size: 15px;
    border-bottom: 1px solid rgba(0, 0, 0, 0.05);
    color: var(--text-dark);
  }
  
  .nav-link:first-child {
    padding-top: 20px;
  }
  
  .nav-link:hover,
  .nav-link.active {
    color: var(--primary);
    background: var(--primary-light);
    padding-left: 24px;
  }
  
  .mobile-menu-overlay {
    display: block;
    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, visibility 0.3s ease;
  }
  
  .mobile-menu-overlay.active {
    opacity: 1;
    visibility: visible;
  }
  
  .footer-container {
    grid-template-columns: 1fr;
    gap: 24px;
    padding: 0 20px;
  }
  
  .footer-nav {
    grid-template-columns: 1fr 1fr;
    gap: 6px 12px;
  }
  
  .footer-bottom {
    flex-direction: column;
    text-align: center;
    padding: 12px 16px;
  }
  
  .page-content img {
    max-width: 100% !important;
    height: auto !important;
    display: block;
  }
  
  .page-content {
    overflow-x: hidden;
    max-width: 100%;
  }
}

@media (min-width: 769px) and (max-width: 992px) {
  .nav-container {
    gap: 2px;
  }
  
  .nav-link {
    padding: 8px 8px;
    font-size: 13px;
  }
}
/* 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;
}