:root {
  --primary: #E53935;
  --secondary: #FF5A4F;
  --primary-dark: #c62828;
  --primary-light: #ff8a80;
  --bg-color: #F5F7FA;
  --card-bg: #FFFFFF;
  --text-main: #333333;
  --border-color: #E0E0E0;
  --header-offset: 122px;
  --header-offset-mobile: 110px;
}

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

/* ========== HEADER ========== */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
}

/* Header Top Area */
.header-top {
  background-color: #b71c1c;
  width: 100%;
}

.header-container {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 10px 25px;
  gap: 15px;
}

/* Logo */
.logo {
  display: block;
  flex-shrink: 0;
  color: #ffffff;
  font-size: 28px;
  font-weight: 800;
  text-decoration: none;
  text-transform: uppercase;
  letter-spacing: 2px;
  line-height: 1.2;
  background: linear-gradient(135deg, #ffffff 0%, #ffccbc 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  text-shadow: 0 2px 4px rgba(0,0,0,0.3);
}

/* Desktop Nav Buttons */
.desktop-nav-buttons {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-shrink: 0;
}

.btn {
  display: inline-block;
  padding: 10px 20px;
  font-size: 14px;
  font-weight: 600;
  text-decoration: none;
  border: none;
  border-radius: 6px;
  cursor: pointer;
  text-align: center;
  transition: all 0.3s ease;
  color: #ffffff;
  line-height: 1.2;
  white-space: nowrap;
}

.btn-primary {
  background: linear-gradient(180deg, #FF5A4F 0%, #E53935 100%);
  box-shadow: 0 2px 8px rgba(229, 57, 53, 0.4);
}

.btn-primary:hover {
  box-shadow: 0 4px 16px rgba(229, 57, 53, 0.6);
  transform: translateY(-2px);
}

.btn-secondary {
  background: linear-gradient(180deg, #ffffff 0%, #f5f5f5 100%);
  color: #E53935;
  border: 2px solid #E53935;
}

.btn-secondary:hover {
  background: #fff5f5;
  box-shadow: 0 4px 12px rgba(229, 57, 53, 0.2);
  transform: translateY(-2px);
}

.btn-download {
  background: linear-gradient(180deg, #43e97b 0%, #38f9d7 100%);
  color: #1a4731;
  box-shadow: 0 2px 8px rgba(56, 249, 215, 0.4);
}

.btn-download:hover {
  box-shadow: 0 4px 16px rgba(56, 249, 215, 0.6);
  transform: translateY(-2px);
}

/* Hamburger Menu */
.hamburger-menu {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 10px;
  flex-direction: column;
  gap: 5px;
  z-index: 1001;
}

.hamburger-menu span {
  display: block;
  width: 25px;
  height: 3px;
  background-color: #ffffff;
  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);
}

/* Main Navigation */
.main-nav {
  background-color: #ffffff;
  display: flex;
  width: 100%;
  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;
  padding: 10px 20px;
  gap: 5px;
  width: 100%;
}

.nav-container a {
  color: var(--text-main);
  text-decoration: none;
  font-size: 14px;
  font-weight: 500;
  padding: 8px 14px;
  border-radius: 4px;
  transition: all 0.3s ease;
  white-space: nowrap;
}

.nav-container a:hover {
  color: var(--primary);
  background-color: #fce4e4;
}

.nav-container a:first-child {
  color: var(--primary);
  font-weight: 700;
  font-size: 15px;
}

/* Mobile Menu Overlay */
.mobile-menu-overlay {
  display: none;
}

/* Mobile Nav Buttons */
.mobile-nav-buttons {
  display: none;
}

/* ========== FOOTER ========== */
.site-footer {
  background-color: #2d2d2d;
  color: #cccccc;
  padding: 50px 0 20px;
  margin-top: 50px;
}

.footer-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 30px;
  margin-bottom: 30px;
}

.footer-brand .footer-logo {
  color: #ffffff;
  font-size: 24px;
  font-weight: 700;
  text-decoration: none;
  text-transform: uppercase;
}

.footer-desc {
  margin-top: 15px;
  font-size: 14px;
  line-height: 1.6;
}

.footer-links h4 {
  color: #ffffff;
  font-size: 16px;
  font-weight: 600;
  margin-bottom: 15px;
}

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

.footer-nav a {
  color: #cccccc;
  text-decoration: none;
  font-size: 14px;
  transition: color 0.3s ease;
}

.footer-nav a:hover {
  color: var(--secondary);
}

.footer-contact p {
  font-size: 14px;
  line-height: 1.8;
  margin: 0;
}

.footer-bottom {
  border-top: 1px solid #444444;
  padding-top: 20px;
  text-align: center;
  font-size: 14px;
  color: #999999;
}

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

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

  /* Header Container */
  .header-container {
    width: 100%;
    max-width: none;
    padding: 10px 15px;
    justify-content: space-between;
  }

  /* Logo */
  .logo {
    font-size: 22px;
    margin: 0 auto;
  }

  /* Hide Desktop Buttons */
  .desktop-nav-buttons {
    display: none;
  }

  /* Show Hamburger */
  .hamburger-menu {
    display: flex;
    order: -1;
    padding: 8px;
  }

  /* Main Nav - Mobile */
  .main-nav {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 75%;
    max-width: 300px;
    height: 100vh;
    background-color: #ffffff;
    flex-direction: column;
    transform: translateX(-100%);
    transition: transform 0.3s ease;
    z-index: 1000;
    border-right: 2px solid #f0f0f0;
    padding-top: 70px;
    box-shadow: 2px 0 15px rgba(0,0,0,0.2);
  }

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

  .nav-container {
    width: 100%;
    max-width: none;
    flex-direction: column;
    padding: 0;
    align-items: flex-start;
  }

  .nav-container a {
    display: block;
    width: 100%;
    padding: 12px 20px;
    font-size: 15px;
    border-bottom: 1px solid #f0f0f0;
    color: #333333;
  }

  .nav-container a:hover {
    background-color: #fce4e4;
    color: var(--primary);
  }

  .nav-container a:first-child {
    font-size: 16px;
  }

  /* Mobile Nav Buttons */
  .mobile-nav-buttons {
    display: flex;
    justify-content: center;
    gap: 8px;
    padding: 8px 10px 10px;
    background-color: #b71c1c;
    border-top: 1px solid rgba(255,255,255,0.1);
    flex-wrap: wrap;
  }

  .mobile-nav-buttons .btn {
    flex: 1;
    min-width: 90px;
    max-width: 130px;
    padding: 8px 10px;
    font-size: 12px;
  }

  /* Mobile Menu Overlay */
  .mobile-menu-overlay {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    z-index: 999;
    cursor: pointer;
  }

  .mobile-menu-overlay.active {
    display: block;
  }

  /* Footer */
  .footer-grid {
    grid-template-columns: 1fr;
    gap: 25px;
  }

  .footer-links, .footer-contact {
    padding-left: 0;
  }

  /* Page Content Protection */
  .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;
}