:root {
  --primary: #2F6BFF;
  --primary-light: #6FA3FF;
  --primary-dark: #1E4FD8;
  --bg-light: #F4F7FB;
  --card-bg: #FFFFFF;
  --text-main: #1F2D3D;
  --border-color: #D6E2FF;
  --glow: #A5C4FF;
  --header-offset: 168px;
  --header-top-height: 68px;
  --main-nav-height: 52px;
  --desktop-breakpoint: 769px;
  --header-total-height: 120px;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  padding-top: var(--header-offset);
  font-family: 'Roboto', 'Segoe UI', Arial, sans-serif;
  background-color: var(--bg-light);
  color: var(--text-main);
  overflow-x: hidden;
}

.site-header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  background-color: #FFFFFF;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
  z-index: 1000;
  display: block;
  min-height: auto;
}

.header-top {
  background: linear-gradient(180deg, #2F6BFF 0%, #1E4FD8 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: var(--header-top-height);
}

.logo {
  font-size: 2rem;
  font-weight: 800;
  color: #FFFFFF;
  text-decoration: none;
  letter-spacing: 1px;
  text-transform: uppercase;
  font-family: 'Playfair Display', Georgia, serif;
  text-shadow: 0 2px 4px rgba(0, 0, 0, 0.3);
  white-space: nowrap;
}

.desktop-nav-buttons {
  display: flex;
  gap: 12px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 10px 20px;
  font-size: 0.9rem;
  font-weight: 600;
  border-radius: 30px;
  text-decoration: none;
  transition: all 0.3s ease;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  color: #FFFFFF;
  background: linear-gradient(180deg, #4A8BFF 0%, #2F6BFF 100%);
  border: none;
  box-shadow: 0 4px 10px rgba(255, 255, 255, 0.3);
}

.btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 15px rgba(0, 0, 0, 0.2);
}

.btn-register {
  background: linear-gradient(180deg, #4A8BFF 0%, #2F6BFF 100%);
  box-shadow: 0 3px 8px rgba(255, 255, 255, 0.3);
}

.btn-login {
  background: linear-gradient(180deg, #6FA3FF 0%, #2F6BFF 100%);
  box-shadow: 0 3px 8px rgba(255, 255, 255, 0.3);
}

.main-nav {
  background-color: #FFFFFF;
  border-top: 3px solid #A5C4FF;
  border-bottom: 1px solid #D6E2FF;
  width: 100%;
  display: flex;
  flex-direction: row;
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  flex-direction: row;
  justify-content: center;
  align-items: center;
  padding: 8px 16px;
  min-height: var(--main-nav-height);
  flex-wrap: wrap;
  gap: 4px 8px;
}

.nav-link {
  font-size: 0.9rem;
  font-weight: 500;
  color: #1F2D3D;
  text-decoration: none;
  padding: 8px 12px;
  border-radius: 4px;
  transition: color 0.3s ease, background-color 0.3s ease;
  white-space: nowrap;
}

.nav-link:hover,
.nav-link.active {
  background-color: #E6EEFF;
  color: #2F6BFF;
}

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

.site-footer {
  background-color: #1F2D3D;
  color: #FFFFFF;
  font-size: 0.9rem;
}

.footer-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 40px 24px 20px;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 30px;
}

.footer-column h4 {
  margin-bottom: 15px;
  font-size: 1rem;
  text-transform: uppercase;
  color: #A5C4FF;
}

.footer-logo {
  font-size: 1.8rem;
  font-weight: 800;
  color: #FFFFFF;
  text-decoration: none;
  display: block;
  margin-bottom: 15px;
}

.footer-desc {
  line-height: 1.6;
  opacity: 0.9;
}

.footer-nav,
.footer-support-links,
.footer-legal-links {
  list-style: none;
}

.footer-nav li,
.footer-support-links li,
.footer-legal-links li {
  margin-bottom: 8px;
}

.footer-nav a,
.footer-support-links a,
.footer-legal-links a {
  color: rgba(255, 255, 255, 0.9);
  text-decoration: none;
  transition: color 0.3s ease, padding-left 0.3s ease;
}

.footer-nav a:hover,
.footer-support-links a:hover,
.footer-legal-links a:hover {
  color: #A5C4FF;
  padding-left: 5px;
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.2);
  padding: 15px;
  text-align: center;
  font-size: 0.85rem;
  opacity: 0.9;
}

@media (max-width: 768px) {
  :root {
    --header-offset: 146px;
    --header-top-height: 60px;
    --main-nav-height: 48px;
  }

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

  .site-header {
    background-color: #2F6BFF;
  }

  .header-top {
    background: linear-gradient(180deg, #2F6BFF 0%, #1E4FD8 100%);
  }

  .header-container {
    width: 100%;
    max-width: none;
    padding: 8px 16px;
    min-height: var(--header-top-height);
    justify-content: space-between;
  }

  .logo {
    font-size: 1.5rem;
    flex: 1;
    text-align: center;
    order: 2;
    margin: 0 auto;
    padding-left: 40px;
    padding-right: 40px;
  }

  .hamburger-menu {
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    width: 40px;
    height: 40px;
    background: transparent;
    border: none;
    cursor: pointer;
    z-index: 1200;
    order: 1;
    padding: 8px;
    background-color: rgba(255, 255, 255, 0.2);
    border-radius: 5px;
  }

  .hamburger-menu span {
    display: block;
    width: 22px;
    height: 3px;
    background-color: #FFFFFF;
    margin: 3px 0;
    transition: transform 0.3s ease, opacity 0.3s ease;
    border-radius: 2px;
  }

  .hamburger-menu.active span:nth-child(1) {
    transform: translateY(9px) rotate(45deg);
  }

  .hamburger-menu.active span:nth-child(2) {
    opacity: 0;
  }

  .hamburger-menu.active span:nth-child(3) {
    transform: translateY(-9px) rotate(-45deg);
  }

  .mobile-nav-buttons {
    display: flex;
    justify-content: center;
    gap: 10px;
    padding: 8px 12px;
    background-color: #1E4FD8;
    width: 100%;
    order: 3;
  }

  .mobile-nav-buttons .btn {
    padding: 8px 16px;
    font-size: 0.8rem;
  }

  .main-nav {
    display: none;
    flex-direction: column;
    position: fixed;
    top: 0;
    right: 0;
    height: 100vh;
    width: 280px;
    background-color: #FFFFFF;
    box-shadow: -4px 0 15px rgba(0, 0, 0, 0.2);
    z-index: 1100;
    transform: translateX(100%);
    transition: transform 0.4s ease;
    padding-top: 100px;
    overflow-y: auto;
  }

  .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-top: 100px;
    gap: 4px;
  }

  .nav-link {
    font-size: 1rem;
    padding: 12px 20px;
    border-bottom: 1px solid #E6EEFF;
    color: #1F2D3D;
    text-align: left;
  }

  .nav-link:hover,
  .nav-link.active {
    background-color: #E6EEFF;
    color: #2F6BFF;
  }

  .mobile-menu-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.6);
    z-index: 1050;
    display: block;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.4s ease, visibility 0.4s ease;
  }

  .mobile-menu-overlay.active {
    opacity: 1;
    visibility: visible;
  }

  .footer-container {
    grid-template-columns: 1fr;
    gap: 20px;
    padding: 30px 16px 15px;
  }

  .footer-bottom {
    padding: 10px;
    font-size: 0.8rem;
  }

  .page-content {
    overflow-x: hidden;
    max-width: 100%;
  }

  .page-content img {
    max-width: 100% !important;
    height: auto !important;
    display: block;
  }

  body {
    overflow-x: hidden;
  }
}

@media (min-width: 769px) {
  .desktop-nav-buttons {
    display: flex !important;
  }

  .mobile-nav-buttons {
    display: none !important;
  }

  .hamburger-menu {
    display: none !important;
  }

  .mobile-menu-overlay {
    display: none !important;
  }

  .main-nav {
    display: flex !important;
  }

  .header-container {
    padding: 10px 20px;
  }

  .logo {
    font-size: 1.8rem;
  }

  .desktop-nav-buttons .btn {
    padding: 8px 18px;
    font-size: 0.85rem;
  }

  .footer-column {
    text-align: left;
  }
}
/* 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;
}