:root {
  --primary-color: #E53935;
  --secondary-color: #FF5A4F;
  --text-main: #333333;
  --bg-light: #F5F7FA;
  --card-bg: #FFFFFF;
  --border-color: #E0E0E0;
  --header-offset: 122px;
}
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}
body {
  padding-top: var(--header-offset);
  font-family: 'Arial', sans-serif;
  background-color: var(--bg-light);
  color: var(--text-main);
}
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.2);
  background-color: var(--card-bg);
  min-height: auto;
}
.header-top {
  background-color: var(--primary-color);
  width: 100%;
  min-height: 68px;
  display: flex;
  align-items: center;
}
.header-container {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 0 30px;
  width: 100%;
}
.logo {
  font-size: 34px;
  font-weight: 900;
  color: #fff;
  text-decoration: none;
  letter-spacing: 1px;
  text-transform: uppercase;
  display: block;
  line-height: 1.2;
}
.logo:hover {
  opacity: 0.9;
}
.desktop-nav-buttons {
  display: flex;
  gap: 12px;
  align-items: center;
}
.btn {
  display: inline-block;
  padding: 10px 24px;
  border-radius: 50px;
  font-size: 14px;
  font-weight: 700;
  text-decoration: none;
  color: #fff;
  text-align: center;
  transition: all 0.3s ease;
  box-shadow: 0 4px 10px rgba(0, 0, 0, 0.2);
  border: none;
  line-height: 1.4;
}
.btn-register {
  background: linear-gradient(180deg, var(--secondary-color) 0%, var(--primary-color) 100%);
}
.btn-login {
  background: linear-gradient(180deg, #4CAF50 0%, #2E7D32 100%);
}
.btn-download {
  background: linear-gradient(180deg, #2196F3 0%, #1565C0 100%);
}
.btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 15px rgba(0, 0, 0, 0.3);
  opacity: 0.95;
}
.main-nav {
  background-color: #FFFFFF;
  border-top: 3px solid var(--primary-color);
  border-bottom: 2px solid var(--secondary-color);
  width: 100%;
  display: flex;
  align-items: center;
  min-height: 52px;
}
.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  flex-direction: row;
  justify-content: center;
  align-items: center;
  gap: 0;
  padding: 0 20px;
  width: 100%;
  flex-wrap: wrap;
}
.nav-link {
  color: var(--text-main);
  text-decoration: none;
  font-size: 15px;
  font-weight: 700;
  padding: 14px 16px;
  display: block;
  transition: color 0.3s ease;
  border-bottom: 3px solid transparent;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}
.nav-link:hover {
  color: var(--primary-color);
  border-bottom-color: var(--secondary-color);
}
.mobile-bottom-buttons {
  display: none;
}
.hamburger-menu {
  display: none;
}
.mobile-menu-overlay {
  display: none;
}
.site-footer {
  background: linear-gradient(180deg, #1a1a2e 0%, #0f0f1a 100%);
  color: #e0e0e0;
  padding: 60px 30px 0;
  border-top: 4px solid var(--primary-color);
}
.footer-container {
  max-width: 1200px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: 2fr 1fr 1.2fr;
  gap: 40px;
  padding-bottom: 40px;
}
.footer-column h3 {
  color: #fff;
  font-size: 18px;
  margin-bottom: 20px;
  text-transform: uppercase;
  letter-spacing: 1px;
  position: relative;
  padding-bottom: 10px;
}
.footer-column h3::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 40px;
  height: 3px;
  background: linear-gradient(90deg, var(--secondary-color), var(--primary-color));
  border-radius: 2px;
}
.footer-logo {
  font-size: 36px;
  font-weight: 900;
  color: #fff;
  text-decoration: none;
  text-transform: uppercase;
  display: block;
  margin-bottom: 20px;
  letter-spacing: 1px;
}
.footer-brand p {
  color: #b0b0b0;
  font-size: 14px;
  line-height: 1.8;
}
.footer-nav {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 12px;
}
.footer-nav li a {
  color: #c0c0c0;
  text-decoration: none;
  font-size: 15px;
  transition: color 0.3s ease, padding-left 0.3s ease;
  display: inline-block;
}
.footer-nav li a:hover {
  color: var(--secondary-color);
  padding-left: 8px;
}
.footer-bottom {
  text-align: center;
  padding: 20px 0;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  color: #888;
  font-size: 14px;
}
@media (max-width: 768px) {
  :root {
    --header-offset: 146px;
  }
  body {
    padding-top: var(--header-offset);
  }
  .site-header {
    min-height: auto;
  }
  .header-top {
    min-height: 60px;
    position: relative;
  }
  .header-container {
    width: 100%;
    max-width: none;
    padding: 0 15px;
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 10px;
  }
  .logo {
    font-size: 28px;
    order: 2;
    flex: 1;
    text-align: center;
  }
  .desktop-nav-buttons {
    display: none;
  }
  .hamburger-menu {
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 5px;
    order: 1;
    width: 44px;
    height: 44px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 8px;
    flex-shrink: 0;
    z-index: 1001;
    border-radius: 8px;
  }
  .hamburger-menu span {
    display: block;
    width: 28px;
    height: 3px;
    background-color: #fff;
    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-nav {
    display: none;
    position: fixed;
    top: 0;
    right: 0;
    width: 100%;
    height: 100vh;
    background-color: #fff;
    z-index: 1000;
    align-items: flex-start;
    justify-content: center;
    padding-top: 80px;
    transform: translateX(100%);
    transition: transform 0.3s ease;
    overflow-y: auto;
    border: none;
  }
  .main-nav.active {
    display: block;
    transform: translateX(0);
  }
  .nav-container {
    width: 100%;
    max-width: none;
    display: flex;
    flex-direction: column;
    justify-content: flex-start;
    align-items: center;
    gap: 0;
    padding: 0;
  }
  .nav-link {
    font-size: 16px;
    padding: 16px 0;
    width: 100%;
    text-align: center;
    border-bottom: 1px solid rgba(0, 0, 0, 0.05);
    border-bottom-color: transparent;
    color: var(--text-main);
    font-weight: 600;
  }
  .nav-link:hover {
    color: var(--primary-color);
    background-color: rgba(229, 57, 53, 0.05);
  }
  .mobile-bottom-buttons {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 8px;
    padding: 10px 15px;
    background-color: #fff;
    width: 100%;
    border-bottom: 2px solid var(--secondary-color);
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    position: relative;
    z-index: 998;
    flex-wrap: wrap;
  }
  .mobile-bottom-buttons .btn {
    padding: 9px 18px;
    font-size: 13px;
    flex: 1;
    max-width: 160px;
    min-width: 100px;
    text-align: center;
  }
  .mobile-menu-overlay {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100vh;
    background-color: rgba(0, 0, 0, 0.5);
    z-index: 999;
  }
  .mobile-menu-overlay.active {
    display: block;
  }
  .footer-container {
    grid-template-columns: 1fr;
    gap: 30px;
    text-align: center;
  }
  .footer-column h3::after {
    left: 50%;
    transform: translateX(-50%);
  }
  .footer-nav {
    align-items: center;
  }
  .footer-logo {
    text-align: center;
  }
  .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;
}