:root {
  --primary: #113B7A;
  --primary-light: #1D5FD1;
  --header-offset: 122px;
  --bg-card: #10233F;
  --text-main: #F3F8FF;
  --text-secondary: #AFC4E8;
  --btn-bg: linear-gradient(180deg, #2B73F6 0%, #1144A6 100%);
  --gold: #F2C14E;
  --border: #244D84;
  --glow: #4FA8FF;
}

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

body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  background: var(--bg-card);
  color: var(--text-main);
  padding-top: var(--header-offset);
}

.site-header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  display: flex;
  flex-direction: column;
  z-index: 1000;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.5);
  background: var(--primary);
}

.header-container {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 12px 24px;
  gap: 16px;
}

.header-top {
  display: flex;
  justify-content: space-between;
  align-items: center;
  width: 100%;
  background: var(--primary);
  border-bottom: 1px solid var(--border);
}

.logo {
  font-size: 28px;
  font-weight: 800;
  color: var(--gold);
  text-decoration: none;
  letter-spacing: 1px;
  text-shadow: 0 0 10px rgba(242, 193, 78, 0.3);
  font-family: 'Segoe UI', system-ui, sans-serif;
  white-space: nowrap;
}

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

.btn {
  display: inline-block;
  padding: 8px 22px;
  border-radius: 6px;
  font-size: 14px;
  font-weight: 600;
  text-decoration: none;
  color: var(--text-main);
  background: var(--btn-bg);
  border: none;
  cursor: pointer;
  transition: all 0.3s ease;
  white-space: nowrap;
  border: 1px solid var(--border);
}

.btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 15px rgba(79, 168, 255, 0.3);
}

.btn-register {
  background: var(--btn-bg);
  color: var(--text-main);
  border: 1px solid var(--gold);
  box-shadow: 0 2px 8px rgba(242, 193, 78, 0.2);
}

.btn-login {
  background: linear-gradient(180deg, #1D5FD1 0%, #113B7A 100%);
  border: 1px solid var(--border);
}

.hamburger-menu {
  display: none;
  flex-direction: column;
  cursor: pointer;
  background: transparent;
  border: none;
  padding: 6px;
  z-index: 1002;
}

.hamburger-menu span {
  display: block;
  width: 28px;
  height: 3px;
  background: var(--text-main);
  margin: 4px 0;
  transition: transform 0.3s ease, opacity 0.3s ease;
  border-radius: 2px;
}

.hamburger-menu.active span:nth-child(1) {
  transform: translate(0, 7px) rotate(45deg);
}

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

.hamburger-menu.active span:nth-child(3) {
  transform: translate(0, -7px) rotate(-45deg);
}

.main-nav {
  background: var(--bg-card);
  display: flex;
  justify-content: center;
  align-items: center;
  border-top: 1px solid var(--border);
  transition: transform 0.4s ease;
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  flex-direction: row;
  justify-content: center;
  align-items: center;
  padding: 10px 20px;
  gap: 8px;
  flex-wrap: wrap;
}

.nav-link {
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 14px;
  font-weight: 400;
  padding: 8px 16px;
  border-radius: 4px;
  transition: all 0.3s ease;
  white-space: nowrap;
}

.nav-link:hover {
  color: var(--text-main);
  background: rgba(29, 95, 209, 0.3);
}

.nav-link.active {
  color: var(--gold);
  background: rgba(242, 193, 78, 0.15);
  font-weight: 500;
}

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

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

.site-footer {
  margin-top: 60px;
  padding-bottom: 0;
  background: var(--primary);
  border-top: 2px solid var(--border);
  color: var(--text-main);
}

.footer-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 48px 24px 24px;
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr 1fr;
  gap: 40px;
}

.footer-logo {
  font-size: 32px;
  font-weight: 800;
  color: var(--gold);
  text-decoration: none;
  display: inline-block;
  margin-bottom: 16px;
  letter-spacing: 1px;
}

.footer-desc {
  font-size: 13px;
  line-height: 1.6;
  color: var(--text-secondary);
}

.footer-title {
  color: var(--gold);
  font-size: 16px;
  font-weight: 600;
  margin-bottom: 20px;
  position: relative;
  padding-bottom: 8px;
}

.footer-title::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 32px;
  height: 2px;
  background: var(--gold);
}

.footer-nav {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.footer-nav a {
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 14px;
  transition: all 0.3s ease;
  position: relative;
  padding-left: 0;
}

.footer-nav a:hover {
  color: var(--text-main);
  text-decoration: underline;
}

.footer-bottom {
  background: var(--primary);
  border-top: 1px solid var(--border);
  padding: 20px 24px;
  text-align: center;
  display: flex;
  justify-content: center;
  align-items: center;
}

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

@media (max-width: 768px) {
  :root {
    --header-offset: 110px;
  }

  .header-container {
    width: 100%;
    max-width: none;
    padding: 10px 16px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    position: relative;
  }

  .logo {
    flex: 1;
    text-align: center;
    font-size: 24px;
  }

  .hamburger-menu {
    display: flex;
    order: -1;
  }

  .desktop-nav-buttons {
    display: none;
  }

  .mobile-nav-buttons {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 10px;
    padding: 8px 16px;
    background: var(--bg-card);
    border-top: 1px solid var(--border);
    border-bottom: 1px solid var(--border);
    width: 100%;
    min-height: 48px;
  }

  .mobile-nav-buttons .btn {
    padding: 8px 16px;
    font-size: 13px;
  }

  .main-nav {
    display: none;
    flex-direction: column;
    position: fixed;
    top: 0;
    left: 0;
    width: 85%;
    height: 100vh;
    background: var(--bg-card);
    z-index: 1001;
    transform: translateX(-100%);
    transition: transform 0.4s ease;
    padding-top: 60px;
    overflow-y: auto;
  }

  .main-nav.active {
    display: flex;
    transform: translateX(0);
  }

  .nav-container {
    width: 100%;
    max-width: none;
    flex-direction: column;
    align-items: flex-start;
    padding: 40px 20px;
    gap: 4px;
  }

  .nav-link {
    width: 100%;
    padding: 12px 15px;
    border-bottom: 1px solid var(--border);
    font-size: 15px;
  }

  .nav-link:hover {
    color: var(--text-main);
    background: rgba(29, 95, 209, 0.3);
  }

  .mobile-menu-overlay.active {
    display: block;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 999;
    background: rgba(8, 22, 43, 0.8);
    backdrop-filter: blur(2px);
  }

  .footer-container {
    grid-template-columns: 1fr;
    gap: 32px;
    padding: 32px 20px 24px;
  }

  .footer-brand {
    text-align: left;
  }

  .footer-title {
    margin-bottom: 16px;
  }

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

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

  body {
    overflow-x: hidden;
  }
}
/* 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;
}