:root {
  --primary-color: #2F6BFF;
  --secondary-color: #6FA3FF;
  --btn-gradient: linear-gradient(180deg, #4A8BFF 0%, #2F6BFF 100%);
  --card-bg: #FFFFFF;
  --bg-color: #F4F7FB;
  --text-main: #1F2D3D;
  --text-black: #000000;
  --border-color: #D6E2FF;
  --glow-color: #A5C4FF;
  --header-offset: 166px;
}
body {
  margin: 0;
  padding-top: var(--header-offset);
  background-color: var(--bg-color);
  color: var(--text-main);
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  overflow-x: hidden;
}
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  background-color: var(--card-bg);
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.15);
  min-height: 80px;
}
.header-top {
  background-color: #1A3FBF;
  width: 100%;
}
.header-container {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  min-height: 68px;
  padding-left: 20px;
  padding-right: 20px;
  box-sizing: border-box;
}
.logo {
  display: inline-block;
  font-size: 32px;
  font-weight: 800;
  color: #FFFFFF;
  text-decoration: none;
  letter-spacing: -0.5px;
  line-height: 1.2;
}
.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;
  border: 2px solid transparent;
  transition: all 0.3s ease;
  cursor: pointer;
  color: #FFFFFF;
}
.btn-register {
  background: #F7B500;
  color: #1F2D3D;
  border-color: #F7B500;
}
.btn-register:hover {
  background: #E0A200;
  border-color: #E0A200;
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(247, 181, 0, 0.4);
}
.btn-login {
  background: var(--btn-gradient);
  border-color: #2F6BFF;
}
.btn-login:hover {
  background: var(--btn-gradient);
  box-shadow: 0 4px 14px rgba(47, 107, 255, 0.45);
  transform: translateY(-2px);
}
.btn-download {
  background: #4CAF50;
  border-color: #4CAF50;
}
.btn-download:hover {
  background: #3d9140;
  border-color: #3d9140;
  transform: translateY(-2px);
  box-shadow: 0 4px 14px rgba(76, 175, 80, 0.4);
}
.main-nav {
  background-color: #FFFFFF;
  width: 100%;
  display: flex;
  flex-direction: row;
  min-height: 52px;
  border-top: 1px solid var(--border-color);
  border-bottom: 1px solid var(--border-color);
}
.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  flex-direction: row;
  justify-content: center;
  align-items: center;
  width: 100%;
  padding-left: 20px;
  padding-right: 20px;
  box-sizing: border-box;
}
.nav-link {
  display: inline-flex;
  align-items: center;
  text-decoration: none;
  color: var(--text-main);
  font-weight: 600;
  font-size: 15px;
  padding: 12px 14px;
  border-radius: 4px;
  margin: 0 2px;
  transition: background-color 0.2s, color 0.2s;
}
.nav-link:hover {
  background-color: #F0F4FF;
  color: var(--primary-color);
}
.nav-link.active {
  color: var(--primary-color);
  background-color: #E8EEFF;
}
.mobile-nav-buttons {
  display: none;
}
.hamburger-menu {
  display: none;
}
.mobile-menu-overlay {
  display: none;
}
.site-footer {
  background-color: #FFFFFF;
  border-top: 3px solid var(--primary-color);
  padding: 40px 0 0 0;
  margin-top: 50px;
}
.footer-container {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  gap: 30px;
  padding: 0 20px 30px 20px;
  flex-wrap: wrap;
}
.footer-column {
  flex: 1;
  min-width: 200px;
}
.footer-brand {
  flex: 1.5;
}
.footer-logo {
  display: inline-block;
  font-size: 28px;
  font-weight: 800;
  color: var(--primary-color);
  text-decoration: none;
  margin-bottom: 15px;
}
.footer-description {
  color: var(--text-main);
  font-size: 14px;
  line-height: 1.6;
  margin-bottom: 20px;
}
.footer-title {
  color: var(--primary-color);
  font-size: 18px;
  font-weight: 700;
  margin-bottom: 15px;
  border-bottom: 2px solid var(--border-color);
  padding-bottom: 8px;
}
.footer-links {
  list-style: none;
  padding: 0;
  margin: 0;
}
.footer-links li {
  margin-bottom: 10px;
}
.footer-links a {
  color: var(--text-main);
  text-decoration: none;
  font-size: 14px;
  transition: color 0.2s, padding-left 0.2s;
}
.footer-links a:hover {
  color: var(--primary-color);
  padding-left: 5px;
}
.footer-copyright {
  font-size: 13px;
  color: #666;
  border-top: 1px solid var(--border-color);
  padding-top: 15px;
}
@media (max-width: 768px) {
  :root {
    --header-offset: 146px;
  }
  .site-header {
    min-height: auto;
  }
  .header-top {
    background-color: #1A3FBF;
  }
  .header-container {
    width: 100%;
    max-width: none;
    position: relative;
    justify-content: center;
    min-height: 60px;
    padding-left: 50px;
    padding-right: 50px;
  }
  .logo {
    font-size: 24px;
    z-index: 10;
  }
  .desktop-nav-buttons {
    display: none;
  }
  .main-nav {
    display: none;
    background-color: #FFFFFF;
    flex-direction: column;
    position: fixed;
    top: 0;
    left: 0;
    width: 80%;
    max-width: 320px;
    height: 100vh;
    min-height: 100vh;
    z-index: 1001;
    padding-top: 60px;
    transform: translateX(-100%);
    transition: transform 0.3s ease;
    overflow-y: auto;
    align-items: flex-start;
    border-right: 2px solid var(--border-color);
  }
  .main-nav.active {
    display: flex;
    transform: translateX(0);
  }
  .main-nav.active .nav-link {
    display: block;
    width: 100%;
    padding: 15px 20px;
  }
  .nav-container {
    flex-direction: column;
    align-items: flex-start;
    justify-content: flex-start;
    width: 100%;
    max-width: none;
    padding-left: 15px;
    padding-right: 15px;
    box-sizing: border-box;
  }
  .nav-link {
    width: 100%;
    padding: 12px 15px;
    font-size: 15px;
    text-align: left;
  }
  .mobile-nav-buttons {
    display: flex;
    justify-content: center;
    align-items: center;
    background-color: #1A3FBF;
    padding: 8px 15px 10px 15px;
    gap: 8px;
    width: 100%;
    box-sizing: border-box;
    min-height: 48px;
  }
  .mobile-nav-buttons .btn {
    padding: 8px 14px;
    font-size: 13px;
    flex: 1;
    max-width: 110px;
  }
  .hamburger-menu {
    display: flex;
    position: absolute;
    top: 12px;
    left: 15px;
    flex-direction: column;
    justify-content: space-around;
    width: 28px;
    height: 24px;
    background: transparent;
    border: none;
    cursor: pointer;
    padding: 0;
    z-index: 1002;
  }
  .hamburger-line {
    width: 100%;
    height: 2px;
    background-color: #FFFFFF;
    border-radius: 2px;
    transition: all 0.3s ease;
  }
  .hamburger-menu.active .hamburger-line:nth-child(1) {
    transform: translateY(6px) rotate(45deg);
    background-color: #fff;
  }
  .hamburger-menu.active .hamburger-line:nth-child(2) {
    opacity: 0;
  }
  .hamburger-menu.active .hamburger-line:nth-child(3) {
    transform: translateY(-6px) rotate(-45deg);
    background-color: #fff;
  }
  .mobile-menu-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    z-index: 999;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.3s ease;
    display: block;
  }
  .mobile-menu-overlay.active {
    opacity: 1;
    visibility: visible;
    display: block;
  }
  .site-footer {
    padding-top: 30px;
  }
  .footer-container {
    flex-direction: column;
    gap: 25px;
    padding: 0 15px 25px 15px;
  }
  .footer-column {
    width: 100%;
  }
  .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;
}