:root {
  --header-offset: 122px; /* Desktop: 68px (header-top) + 52px (main-nav) = 120px + 2px buffer */
  --primary-color: #FF8C1A;
  --secondary-color: #FFA53A;
  --card-bg: #17191F;
  --background-color: #0D0E12;
  --text-main: #FFF3E6;
  --border-color: #A84F0C;
  --glow-color: #FFB04D;
  --deep-orange: #D96800;
}

body {
  margin: 0;
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  color: var(--text-main);
  background-color: var(--background-color);
  padding-top: var(--header-offset);
  overflow-x: hidden; /* Global for mobile overflow prevention */
}

body.no-scroll {
  overflow: hidden;
}

a {
  text-decoration: none;
  color: var(--text-main);
}

.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  width: 100%;
  z-index: 1000;
  box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
  box-sizing: border-box;
}

.header-top {
  box-sizing: border-box;
  min-height: 68px;
  height: 68px;
  display: flex;
  align-items: center;
  overflow: hidden;
  background-color: var(--background-color);
  width: 100%;
  padding: 0 20px; /* Default padding for desktop */
}

.header-container {
  box-sizing: border-box;
  width: 100%;
  height: 100%;
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  font-size: 28px;
  font-weight: bold;
  color: var(--primary-color);
  text-transform: uppercase;
  letter-spacing: 1px;
  display: flex;
  align-items: center;
  height: 100%;
}

.logo img {
  display: block;
  max-height: 60px;
  height: auto;
  width: auto;
  max-width: 280px;
  object-fit: contain;
}

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

.btn {
  padding: 10px 20px;
  border-radius: 5px;
  font-weight: bold;
  text-align: center;
  cursor: pointer;
  transition: background-color 0.3s ease, transform 0.2s ease;
  white-space: nowrap;
  text-decoration: none;
  color: var(--text-main);
  background: linear-gradient(180deg, var(--secondary-color) 0%, var(--deep-orange) 100%);
  border: none;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
}

.btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 8px rgba(0, 0, 0, 0.3);
}

.hamburger-menu {
  display: none; /* Hidden on desktop */
  width: 30px;
  height: 24px;
  position: relative;
  cursor: pointer;
  flex-direction: column;
  justify-content: space-between;
  z-index: 1001;
}

.hamburger-menu span {
  display: block;
  width: 100%;
  height: 3px;
  background-color: var(--text-main);
  transition: all 0.3s ease;
  border-radius: 2px;
}

.main-nav {
  box-sizing: border-box;
  min-height: 52px;
  height: 52px;
  display: flex;
  align-items: center;
  overflow: hidden;
  background-color: var(--card-bg);
  width: 100%;
  padding: 0 20px; /* Default padding for desktop */
}

.nav-container {
  box-sizing: border-box;
  height: 100%;
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  flex-direction: row;
  justify-content: center;
  align-items: center;
  gap: 25px; /* Spacing between nav links */
  width: 100%;
}

.nav-link {
  font-size: 16px;
  font-weight: 500;
  padding: 5px 0;
  color: var(--text-main);
  position: relative;
  transition: color 0.3s ease;
}

.nav-link::after {
  content: '';
  position: absolute;
  left: 0;
  bottom: 0;
  width: 0;
  height: 2px;
  background-color: var(--primary-color);
  transition: width 0.3s ease;
}

.nav-link:hover::after,
.nav-link.active::after {
  width: 100%;
}

.overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(0, 0, 0, 0.7);
  z-index: 999;
  display: none; /* Hidden by default */
  opacity: 0;
  transition: opacity 0.3s ease;
}

.overlay.active {
  display: block;
  opacity: 1;
}

.mobile-nav-buttons {
  box-sizing: border-box;
  display: none; /* Hidden on desktop */
  min-height: 48px; /* Default min-height for mobile */
  background-color: var(--background-color); /* Same as header-top for consistency */
  padding: 0 15px; /* Mobile padding */
}

/* Footer Styles */
.site-footer {
  background-color: var(--card-bg);
  color: var(--text-main);
  padding: 40px 20px 20px;
  box-sizing: border-box;
  width: 100%;
}

.site-footer h3 {
  color: var(--primary-color);
  font-size: 18px;
  margin-bottom: 20px;
}

.site-footer a {
  color: var(--text-main);
  transition: color 0.3s ease;
}

.site-footer a:hover {
  color: var(--primary-color);
}

.footer-top-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 30px;
  max-width: 1200px;
  margin: 0 auto 30px;
}

.footer-col {
  display: flex;
  flex-direction: column;
}

.footer-logo {
  font-size: 24px;
  font-weight: bold;
  color: var(--primary-color);
  text-transform: uppercase;
  letter-spacing: 1px;
  margin-bottom: 15px;
  display: inline-block;
}

.footer-description {
  font-size: 14px;
  line-height: 1.6;
  margin-bottom: 20px;
  word-wrap: break-word;
  overflow-wrap: break-word;
}

.footer-nav {
  list-style: none;
  padding: 0;
  margin: 0;
}

.footer-nav li {
  margin-bottom: 10px;
}

.footer-bottom-nav {
  max-width: 1200px;
  margin: 0 auto 20px;
  border-top: 1px solid var(--border-color);
  padding-top: 20px;
}

.footer-bottom-nav .footer-nav {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 20px;
}

.footer-bottom-nav .footer-nav li {
  margin-bottom: 0;
}

.footer-bottom {
  text-align: center;
  font-size: 13px;
  color: #aaa;
  padding-top: 20px;
  border-top: 1px solid var(--border-color);
  max-width: 1200px;
  margin: 0 auto;
}

.footer-bottom p {
  margin: 0;
}

/* Mobile responsive styles */
@media (max-width: 768px) {
  :root {
    --header-offset: 110px; /* Mobile: 60px (header-top) + 48px (mobile-nav-buttons) = 108px + 2px buffer */
  }

  .header-top {
    min-height: 60px;
    height: 60px;
    padding: 0 15px; /* Smaller padding for mobile */
  }

  .header-container {
    width: 100%;
    max-width: none; /* No max-width for mobile container */
    padding: 0; /* Handled by header-top padding */
    justify-content: space-between; /* Hamburger left, Logo center, empty space right */
    position: relative; /* For logo absolute positioning */
  }

  .logo {
    font-size: 24px;
    position: absolute; /* For centering */
    left: 50%;
    transform: translateX(-50%);
    z-index: 1; /* Below hamburger menu */
    max-width: calc(100% - 100px); /* Leave space for hamburger */
  }

  .logo img {
    max-height: 56px;
  }

  .desktop-nav-buttons {
    display: none !important; /* Hide desktop buttons */
  }

  .hamburger-menu {
    display: flex; /* Show hamburger on mobile */
    margin-right: auto; /* Push hamburger to left */
  }

  .hamburger-menu.active span:nth-child(1) {
    transform: translateY(10px) rotate(45deg);
  }

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

  .hamburger-menu.active span:nth-child(3) {
    transform: translateY(-11px) rotate(-45deg);
  }

  .mobile-nav-buttons {
    display: flex !important; /* Show mobile buttons */
    min-height: 48px;
    align-items: center;
    justify-content: center; /* Center buttons horizontally */
    width: 100%;
    max-width: 100%;
    box-sizing: border-box;
    padding: 0 15px;
    overflow: hidden;
    gap: 10px;
    flex-wrap: nowrap;
    background-color: var(--background-color); /* Match header-top */
  }

  .mobile-nav-buttons .btn {
    flex: 1;
    min-width: 0;
    max-width: calc(50% - 5px); /* Two buttons with 10px gap */
    box-sizing: border-box;
    padding: 8px 12px;
    font-size: 13px;
    white-space: normal;
    word-wrap: break-word;
    overflow-wrap: break-word;
  }

  .main-nav {
    display: none; /* Hidden by default on mobile */
    position: fixed;
    top: var(--header-offset); /* Position below fixed header and mobile buttons */
    left: 0;
    width: 80%; /* Sidebar width */
    height: calc(100% - var(--header-offset)); /* Full height below header */
    background-color: var(--card-bg);
    flex-direction: column;
    align-items: flex-start;
    padding: 20px;
    box-sizing: border-box;
    transform: translateX(-100%); /* Slide out of view */
    transition: transform 0.3s ease;
    overflow-y: auto; /* Enable scrolling for long menus */
    z-index: 1000; /* Below overlay */
  }

  .main-nav.active {
    display: flex; /* Show when active */
    transform: translateX(0); /* Slide into view */
  }

  .nav-container {
    flex-direction: column;
    align-items: flex-start;
    width: 100%;
    max-width: none; /* No max-width for mobile container */
    padding: 0;
    gap: 15px;
  }

  .nav-link {
    width: 100%;
    padding: 10px 0;
    font-size: 18px;
  }

  .nav-link::after {
    left: 0;
    transform: translateX(0);
  }

  .footer-top-grid {
    grid-template-columns: 1fr; /* Single column for mobile */
    gap: 20px;
  }

  .footer-bottom-nav .footer-nav {
    flex-direction: column;
    gap: 10px;
  }

  .footer-bottom {
    padding-top: 15px;
  }

  .page-content img {
    max-width: 100% !important;
    height: auto !important;
    display: block;
  }
  .page-content {
    overflow-x: hidden;
    max-width: 100%;
  }
}
/* 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;
  }
}