:root {
  --brand-primary: #E53935;
  --brand-secondary: #FF5A4F;
  --header-offset: 122px;
  --bg-card: #FFFFFF;
  --bg-body: #F5F7FA;
  --text-main: #333333;
  --border-color: #E0E0E0;
}
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}
body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, Arial, sans-serif;
  background-color: var(--bg-body);
  color: var(--text-main);
  padding-top: var(--header-offset);
}
a {
  text-decoration: none;
}
img {
  max-width: 100%;
  height: auto;
}
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  min-height: 68px;
  z-index: 1000;
  background-color: var(--brand-primary);
  box-shadow: 0 4px 24px rgba(0, 0, 0, 0.18);
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, Arial, sans-serif;
}
.header-top {
  width: 100%;
  background: linear-gradient(180deg, #df1f1b 0%, #c62828 100%);
}
.header-container {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  flex-direction: row;
  justify-content: space-between;
  align-items: center;
  padding: 8px 30px;
  min-height: 60px;
}
.logo {
  display: inline-flex;
  align-items: center;
  font-size: 2.2rem;
  font-weight: 900;
  font-style: italic;
  letter-spacing: -1px;
  text-transform: lowercase;
  color: #ffffff;
  text-shadow: 0 2px 8px rgba(0, 0, 0, 0.35);
  line-height: 1;
  flex-shrink: 0;
}
.logo:hover,
.logo:focus {
  color: #ffdada;
}
.desktop-nav-buttons {
  display: flex;
  flex-direction: row;
  align-items: center;
  gap: 8px;
  flex-shrink: 0;
}
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 8px 18px;
  border-radius: 24px;
  font-size: 0.9rem;
  font-weight: 700;
  color: #ffffff;
  background: linear-gradient(180deg, #FF5A4F 0%, #E53935 100%);
  box-shadow: 0 3px 8px rgba(229, 57, 53, 0.35);
  border: none;
  cursor: pointer;
  transition: all 0.3s ease;
  white-space: nowrap;
  text-decoration: none !important;
  line-height: 1.2;
}
.btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 16px rgba(229, 57, 53, 0.5);
  filter: brightness(1.1);
  color: #ffffff;
}
.btn-login {
  background: linear-gradient(180deg, #ff665a 0%, #e53935 100%);
}
.btn-register {
  background: linear-gradient(180deg, #fbc02d 0%, #f57f17 100%);
  box-shadow: 0 3px 10px rgba(245, 127, 23, 0.35);
}
.btn-download {
  background: linear-gradient(180deg, #66bb6a 0%, #2e7d32 100%);
  box-shadow: 0 3px 10px rgba(46, 125, 50, 0.35);
}
.main-nav {
  width: 100%;
  background-color: #ffffff;
  display: flex;
  flex-direction: row;
  align-items: center;
  justify-content: center;
  position: static;
  border-top: 3px solid #e53935;
  border-bottom: 1px solid rgba(224, 224, 224, 0.7);
  box-shadow: 0 3px 12px rgba(0, 0, 0, 0.08);
}
.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  flex-direction: row;
  justify-content: center;
  align-items: center;
  padding: 10px 25px;
  width: 100%;
}
.nav-link {
  display: inline-block;
  color: var(--text-main);
  font-size: 1rem;
  font-weight: 700;
  padding: 6px 14px;
  text-transform: uppercase;
  letter-spacing: 0.3px;
  border-radius: 4px;
  transition: all 0.25s ease;
  text-decoration: none;
  white-space: nowrap;
  border-left: 1px solid #ececec;
  line-height: 1.3;
}
.nav-link:first-child {
  border-left: none;
}
.nav-link:hover,
.nav-link:focus {
  background-color: var(--brand-primary);
  color: #ffffff;
  transform: translateY(-1px);
}
.mobile-nav-buttons {
  display: none;
}
.mobile-menu-overlay {
  display: none;
}
.hamburger-menu {
  display: none;
}
.site-footer {
  background-color: #212121;
  color: #dddddd;
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, Arial, sans-serif;
}
.footer-container {
  max-width: 1200px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1.5fr 1fr 1.2fr;
  gap: 32px;
  padding: 48px 30px 32px;
}
.footer-logo {
  font-size: 2rem;
  font-weight: 900;
  font-style: italic;
  text-transform: lowercase;
  color: #ffffff;
  text-decoration: none;
  transition: color 0.3s;
}
.footer-logo:hover {
  color: var(--brand-secondary);
}
.footer-text {
  font-size: 0.9rem;
  color: #bbbbbb;
  margin-top: 16px;
  line-height: 1.5;
}
.footer-heading {
  color: #ffffff;
  font-size: 1rem;
  margin-bottom: 16px;
  font-weight: 600;
  padding-bottom: 8px;
  border-bottom: 2px solid var(--brand-primary);
  display: inline-block;
}
.footer-nav {
  list-style: none;
}
.footer-nav li {
  margin-bottom: 8px;
}
.footer-nav a {
  color: #bbbbbb;
  text-decoration: none;
  font-size: 0.9rem;
  transition: color 0.3s ease;
}
.footer-nav a:hover,
.footer-nav a:focus {
  color: var(--brand-secondary);
  padding-left: 4px;
}
.footer-bottom {
  background-color: #1a1a1a;
  padding: 17px 0;
  border-top: 1px solid #333333;
}
.footer-bottom-container {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 0 30px;
  font-size: 0.85rem;
  color: #aaaaaa;
}
.footer-comply {
  text-align: right;
}
@media (max-width: 768px) {
  :root {
    --header-offset: 110px;
  }
  body {
    padding-top: var(--header-offset);
  }
  .header-top {
    width: 100%;
  }
  .header-container {
    width: 100%;
    max-width: none;
    display: flex;
    flex-direction: row;
    justify-content: space-between;
    align-items: center;
    padding: 8px 16px;
    position: relative;
    min-height: 60px;
  }
  .logo {
    font-size: 1.8rem;
    order: 2;
    margin: 0 auto;
    display: inline-block;
  }
  .hamburger-menu {
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    order: 1;
    width: 36px;
    height: 36px;
    background: transparent;
    border: none;
    cursor: pointer;
    padding: 0;
    z-index: 1001;
    margin-right: auto;
  }
  .hamburger-menu .hamburger-line {
    display: block;
    width: 24px;
    height: 3px;
    background-color: #ffffff;
    margin: 3px 0;
    border-radius: 2px;
    transition: all 0.3s ease;
  }
  .hamburger-menu.active .hamburger-line:nth-child(1) {
    transform: translateY(6px) rotate(45deg);
  }
  .hamburger-menu.active .hamburger-line:nth-child(2) {
    opacity: 0;
  }
  .hamburger-menu.active .hamburger-line:nth-child(3) {
    transform: translateY(-6px) rotate(-45deg);
  }
  .desktop-nav-buttons {
    display: none;
  }
  .mobile-nav-buttons {
    display: flex;
    width: 100%;
    background-color: #fafafa;
    padding: 6px 8px;
    justify-content: center;
    align-items: center;
    gap: 6px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
    z-index: 999;
    border-bottom: 1px solid #f0f0f0;
  }
  .mobile-nav-buttons-container {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 6px;
    width: 100%;
    max-width: 100%;
    flex-wrap: wrap;
  }
  .mobile-nav-buttons .btn {
    flex: 1 1 0;
    max-width: 130px;
    padding: 5px 8px;
    font-size: 0.82rem;
    margin: 0;
    text-align: center;
    gap: 4px;
    min-height: 30px;
    line-height: 1.2;
    letter-spacing: 0.2px;
  }
  .main-nav {
    display: none;
    flex-direction: column;
    position: fixed;
    top: 88px;
    bottom: 0;
    left: 0;
    width: 82%;
    min-width: 280px;
    max-width: 320px;
    background-color: #ffffff;
    padding-bottom: 40px;
    overflow-y: auto;
    z-index: 1002;
    border-top: 1px solid #eeeeee;
    border-right: 1px solid rgba(0, 0, 0, 0.06);
    border-bottom: none;
    border-left: none;
    box-shadow: 0 8px 40px rgba(0, 0, 0, 0.18);
    transform: translateX(-100%);
    transition: transform 0.35s cubic-bezier(0.25, 0.46, 0.45, 0.94);
  }
  .main-nav.active,
  .main-nav.open {
    display: flex;
    transform: translateX(0);
  }
  .nav-container {
    width: 100%;
    flex-direction: column;
    align-items: flex-start;
    justify-content: flex-start;
    padding: 12px 0;
    gap: 0;
    flex: 1;
  }
  .nav-link {
    width: 100%;
    padding: 9px 16px;
    text-align: left;
    font-size: 0.95rem;
    color: #333333;
    border-left: none;
    border-bottom: 1px solid #f5f5f5;
    text-transform: none;
    letter-spacing: 0.2px;
  }
  .nav-link:hover,
  .nav-link:focus {
    background-color: #f6f6f6;
    color: var(--brand-primary);
  }
  .nav-link:last-child {
    border-bottom: none;
  }
  .mobile-menu-overlay {
    display: block;
    position: fixed;
    top: 88px;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.55);
    z-index: 1001;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.35s ease;
  }
  .mobile-menu-overlay.active,
  .mobile-menu-overlay.visible {
    opacity: 1;
    visibility: visible;
  }
  .site-footer {
    text-align: left;
  }
  .footer-container {
    grid-template-columns: 1fr;
    gap: 24px;
    padding: 32px 20px 20px;
  }
  .footer-bottom-container {
    flex-direction: column;
    text-align: center;
    padding: 16px 12px;
    gap: 8px;
  }
  .footer-comply {
    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;
}