:root {
  --primary-color: #26A9E0;
  --primary-dark: #1a7ba3;
  --accent-color: #EA7C07;
  --white-color: #FFFFFF;
  --black-color: #000000;
  --header-offset: 122px;
}
body {
  padding-top: var(--header-offset);
  background: var(--white-color);
}
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.25);
  background: var(--white-color);
  font-family: 'Segoe UI', Arial, sans-serif;
}
.header-top {
  background: var(--primary-dark);
  width: 100%;
  min-height: 68px;
}
.header-top .header-container {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  min-height: 68px;
  padding: 10px 30px;
  box-sizing: border-box;
  gap: 10px;
  flex-wrap: wrap;
}
.logo {
  display: inline-block;
  font-size: 2rem;
  font-weight: 900;
  color: var(--primary-color);
  text-decoration: none;
  background: linear-gradient(145deg, #B3E5FC, #81D4FA, #4FC3F7, #29B6F6, #26A9E0);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  text-fill-color: transparent;
  line-height: 1.2;
  letter-spacing: -0.5px;
  text-shadow: 2px 2px 2px rgba(0, 0, 0, 0.1);
  flex-shrink: 0;
}
.desktop-nav-buttons {
  display: flex;
  align-items: center;
  gap: 10px;
}
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 8px 20px;
  border-radius: 25px;
  font-weight: 700;
  font-size: 0.95rem;
  text-decoration: none;
  border: 2px solid transparent;
  transition: all 0.3s ease;
  cursor: pointer;
  min-height: 40px;
  box-sizing: border-box;
  white-space: nowrap;
}
.btn-login {
  background: var(--accent-color);
  color: var(--white-color);
  border-color: var(--accent-color);
}
.btn-login:hover {
  background: #d67306;
  border-color: #d67306;
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(234, 124, 7, 0.4);
}
.btn-register {
  background: var(--primary-color);
  color: var(--white-color);
  border-color: var(--primary-color);
}
.btn-register:hover {
  background: #1b8fbd;
  border-color: #1b8fbd;
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(38, 169, 224, 0.4);
}
.btn-download {
  background: var(--black-color);
  color: var(--white-color);
  border-color: var(--black-color);
}
.btn-download:hover {
  background: var(--primary-color);
  border-color: var(--primary-color);
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(38, 169, 224, 0.4);
}
.main-nav {
  background: var(--white-color);
  width: 100%;
  border-top: 2px solid var(--primary-color);
  display: flex;
  min-height: 52px;
  overflow: hidden;
}
.nav-container {
  max-width: 1290px;
  margin: 0 auto;
  display: flex;
  flex-direction: row;
  justify-content: center;
  align-items: center;
  width: 100%;
  padding: 5px 10px;
  gap: 5px;
  flex-wrap: nowrap;
}
.nav-link {
  padding: 8px 14px;
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--black-color);
  text-decoration: none;
  text-align: center;
  white-space: nowrap;
  min-height: 40px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  transition: color 0.3s ease, background 0.3s ease, transform 0.3s ease;
  border-radius: 6px;
  text-transform: uppercase;
  letter-spacing: 0.3px;
}
.nav-link:hover {
  color: var(--primary-color);
  background: rgba(38, 169, 224, 0.1);
  transform: translateY(-1px);
}
.mobile-nav-buttons {
  display: none;
}
.hamburger-menu {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 12px;
  z-index: 1001;
  position: absolute;
  top: 10px;
  left: 10px;
}
.hamburger-menu span {
  display: block;
  width: 28px;
  height: 3px;
  background: linear-gradient(90deg, var(--primary-color), var(--primary-dark));
  margin: 5px 0;
  border-radius: 3px;
  transition: all 0.3s ease;
}
.mobile-menu-overlay {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.7);
  z-index: 999;
  opacity: 0;
  transition: opacity 0.3s ease;
}
.mobile-menu-overlay.active {
  opacity: 1;
}
.site-footer {
  background: #f0f5f8;
  color: #333;
  end padding: 40px 0 20px;
  border-top: 2px solid var(--primary-dark);
  font-family: 'Segoe UI', Arial, sans-serif;
}
.footer-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 30px;
}
.footer-column {
  flex: 1;
  min-width: 200px;
}
.footer-logo {
  font-size: 2.2rem;
  font-weight: bold;
  text-decoration: none;
  color: var(--primary-dark);
  background: linear-gradient(145deg, #69c3e0, #1b8fbd);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  text-fill-color: transparent;
  margin-bottom: 15px;
  display: inline-block;
}
.footer-column h3 {
  font-size: 1.1rem;
  color: #222;
  margin-bottom: 15px;
  border-bottom: 2px solid var(--primary-color);
  padding-bottom: 8px;
  font-weight: 700;
}
.footer-column p {
  color: #444;
  line-height: 1.6;
}
.footer-nav {
  list-style: none;
  padding: 0;
  margin: 0;
}
.footer-nav li {
  margin-bottom: 10px;
}
.footer-nav a {
  color: #37474f;
  text-decoration: none;
  transition: color 0.3s ease, padding-left 0.3s ease;
  font-weight: 500;
  padding: 2px 0;
}
.footer-nav a:hover {
  color: var(--primary-dark);
  padding-left: 5px;
  text-decoration: underline;
}
.footer-bottom {
  width: 100%;
  text-align: center;
  padding-top: 25px;
  margin-top: 15px;
  border-top: 1px solid #ddd;
  color: #555;
  font-size: 0.9rem;
}
.footer-bottom p {
  margin: 0;
}
@media (max-width: 992px) {
  .nav-link {
    padding: 8px 8px;
    font-size: 0.8rem;
  }
}
@media (max-width: 768px) {
  body:has(.hamburger-menu.active) {
    overflow: hidden;
  }
  body {
    padding-top: 156px;
  }
  .site-header {
    min-height: 0;
  }
  .header-top {
    min-height: 60px;
    background: var(--primary-dark);
  }
  .header-top .header-container {
    max-width: 100%;
    width: 100%;
    min-height: 60px;
    padding: 8px 45px;
    justify-content: center;
    position: relative;
  }
  .logo {
    font-size: 2rem;
  }
  .desktop-nav-buttons {
    display: none;
  }
  .main-nav {
    display: none;
    position: fixed;
    top: 60px;
    left: 0;
    width: 280px;
    height: calc(100dvh - 60px);
    background: var(--white-color);
    border-top: 2px solid var(--primary-color);
    flex-direction: column;
    justify-content: flex-start;
    align-items: stretch;
    transform: translateX(-100%);
    transition: transform 0.3s ease;
    z-index: 1000;
    padding: 0 0 20px 0;
    overflow-y: auto;
    -webkit-overflow-scrolling: touch;
    box-shadow: 3px 0 15px rgba(0, 0, 0, 0.2);
  }
  .main-nav.active {
    display: flex;
    transform: translateX(0);
  }
  .main-nav .nav-container {
    max-width: 100%;
    width: 100%;
    flex-direction: column;
    align-items: stretch;
    padding: 5px 0;
    gap: 0;
  }
  .nav-link {
    border-bottom: 1px solid #eaeaea;
    border-radius: 0;
    color: var(--black-color);
    display: block;
    width: 100%;
    text-align: left;
    padding: 16px 20px;
    font-size: 1rem;
    min-height: 48px;
    box-sizing: border-box;
  }
  .nav-link:hover {
    background: rgba(38, 169, 224, 0.1);
    color: var(--primary-color);
  }
  .mobile-nav-buttons {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 8px;
    padding: 8px 10px;
    background: #f0f5f8;
    border-bottom: 1px solid #d0d0d0;
    flex-wrap: wrap;
    min-height: 48px;
  }
  .mobile-nav-buttons .btn {
    font-size: 0.85rem;
    padding: 8px 16px;
    min-width: 90px;
    flex: 1;
    max-width: 140px;
  }
  .hamburger-menu {
    display: block;
    top: 5px;
    left: 5px;
  }
  .hamburger-menu.active span:nth-child(1) {
    transform: translateY(8px) rotate(45deg);
    background: var(--primary-dark);
  }
  .hamburger-menu.active span:nth-child(2) {
    opacity: 0;
  }
  .hamburger-menu.active span:nth-child(3) {
    transform: translateY(-8px) rotate(-45deg);
    background: var(--primary-dark);
  }
  .mobile-menu-overlay {
    display: block;
    top: 0;
    left: 0;
    visibility: hidden;
  }
  .mobile-menu-overlay.active {
    display: block;
    visibility: visible;
  }
  body.no-scroll {
    overflow: hidden;
  }
  .page-content img {
    max-width: 100% !important;
    height: auto !important;
    display: block;
  }
  .page-content {
    overflow-x: hidden;
    max-width: 100%;
  }
  body {
    overflow-x: hidden;
    --header-offset: 146px;
  }
  .footer-container {
    flex-direction: column;
    align-items: center;
    text-align: center;
    padding: 0 15px;
  }
  .footer-column {
    min-width: 100%;
    margin-bottom: 5px;
  }
  .footer-nav a {
    padding: 5px 0;
    display: inline-block;
  }
  .footer-logo {
    font-size: 2rem;
  }
  .footer-bottom {
    padding-top: 15px;
    margin-top: 0;
    border-top: none;
  }
}
@media (max-width: 480px) {
  .header-top .header-container {
    padding: 8px 40px;
  }
  .logo {
    font-size: 1.6rem;
  }
  .btn {
    padding: 7px 12px;
    font-size: 0.8rem;
  }
  .mobile-nav-buttons .btn {
    font-size: 0.7rem;
    padding: 6px 8px;
    min-width: 60px;
  }
}
/* 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;
}