:root {
  --primary-color: #26A9E0;
  --secondary-color: #FFFFFF;
  --accent-color: #EA7C07;
  --header-offset: 122px;
  --text-dark: #333333;
}
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}
body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  background-color: var(--secondary-color);
  color: var(--text-dark);
  padding-top: var(--header-offset);
}
a {
  text-decoration: none;
  color: inherit;
}
ul {
  list-style: none;
}
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  background: var(--secondary-color);
  box-shadow: 0 2px 15px rgba(0, 0, 0, 0.2);
  border-bottom: 2px solid rgba(38, 169, 224, 0.3);
}
.header-top {
  background: #1B7FA3;
  width: 100%;
}
.header-container {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 12px 40px;
}
.logo {
  font-size: 1.7rem;
  font-weight: 800;
  color: var(--secondary-color);
  letter-spacing: 0.5px;
  background: linear-gradient(45deg, #FFFFFF, #C0E8FF);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  background-color: transparent;
  text-shadow: none;
  display: inline-block;
  white-space: nowrap;
}
.desktop-nav-buttons {
  display: flex;
  align-items: center;
  gap: 10px;
}
.btn {
  display: inline-block;
  padding: 10px 28px;
  border-radius: 6px;
  font-size: 0.95rem;
  font-weight: 600;
  text-align: center;
  border: none;
  cursor: pointer;
  transition: all 0.3s ease;
  text-decoration: none !important;
  color: var(--secondary-color);
  letter-spacing: 0.3px;
}
.btn-register {
  background: #FF3B6B;
  background: linear-gradient(135deg, #FF3B6B, #FF6B9A);
  box-shadow: 0 3px 10px rgba(255, 59, 107, 0.4);
}
.btn-register:hover {
  transform: translateY(-2px);
  box-shadow: 0 5px 15px rgba(255, 59, 107, 0.5);
}
.btn-login {
  background: var(--accent-color);
  background: linear-gradient(135deg, var(--accent-color), #FCA64B);
  box-shadow: 0 3px 10px rgba(234, 124, 7, 0.4);
}
.btn-login:hover {
  transform: translateY(-2px);
  box-shadow: 0 5px 15px rgba(234, 124, 7, 0.5);
}
.main-nav {
  background: #E6F5FB;
  border-top: 1px solid rgba(38, 169, 224, 0.2);
  border-bottom: 1px solid rgba(38, 169, 224, 0.2);
  width: 100%;
  display: flex;
}
.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  flex-direction: row;
  justify-content: center;
  align-items: center;
  padding: 0 20px;
  flex-wrap: nowrap;
  overflow-x: auto;
}
.nav-container::-webkit-scrollbar {
  display: none;
}
.nav-link {
  display: inline-block;
  padding: 14px 14px;
  font-size: 0.92rem;
  font-weight: 600;
  color: var(--text-dark);
  transition: all 0.3s ease;
  position: relative;
  white-space: nowrap;
  border-bottom: 3px solid transparent;
}
.nav-link:hover, .nav-link.active {
  color: var(--primary-color);
  border-bottom-color: var(--primary-color);
}
.nav-home {
  font-weight: 700;
  font-size: 0.95rem;
}
.mobile-nav-buttons {
  display: none;
}
.hamburger-menu {
  display: none;
  background: transparent;
  border: none;
  cursor: pointer;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 45px;
  height: 45px;
  align-items: center;
  padding: 0;
}
.hamburger-line {
  width: 26px;
  height: 3px;
  background: var(--secondary-color);
  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, 0.5);
  z-index: 998;
}
@media (max-width: 768px) {
  :root {
    --header-offset: 110px;
  }
  .header-container {
    width: 100%;
    max-width: none;
    padding: 10px 15px;
    position: relative;
    justify-content: center;
    min-height: 60px;
  }
  .logo {
    font-size: 1.1rem;
    position: absolute;
    left: 50%;
    transform: translateX(-50%);
    z-index: 3;
    max-width: 60%;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
  }
  .hamburger-menu {
    display: flex;
    position: absolute;
    left: 5px;
    top: 50%;
    transform: translateY(-50%);
    z-index: 1002;
    background: transparent;
    border-radius: 8px;
  }
  .hamburger-menu .hamburger-line {
    display: block;
  }
  .hamburger-menu.active {
    background: rgba(0, 0, 0, 0.2);
  }
  .hamburger-menu.active .hamburger-line:nth-child(1) {
    transform: translateY(8px) rotate(45deg);
  }
  .hamburger-menu.active .hamburger-line:nth-child(2) {
    opacity: 0;
  }
  .hamburger-menu.active .hamburger-line:nth-child(3) {
    transform: translateY(-8px) rotate(-45deg);
  }
  .desktop-nav-buttons {
    display: none;
  }
  .mobile-nav-buttons {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 12px;
    padding: 10px 15px;
    background: #FFFFFF;
    border-bottom: 1px solid rgba(38, 169, 224, 0.2);
    width: 100%;
    z-index: 1000;
    position: relative;
  }
  .mobile-nav-buttons .btn {
    flex: 1;
    max-width: 180px;
    padding: 10px 10px;
    font-size: 0.85rem;
  }
  .main-nav {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 85%;
    max-width: 320px;
    height: 100vh;
    background: var(--secondary-color);
    flex-direction: column;
    z-index: 1001;
    transform: translateX(-100%);
    transition: transform 0.3s ease, display 0s ease 0.3s;
    box-shadow: 2px 0 20px rgba(0, 0, 0, 0.1);
    overflow-y: auto;
    border-radius: 0 20px 20px 0;
    display: none;
  }
  .main-nav.active {
    display: flex;
    transform: translateX(0);
    transition: transform 0.3s ease;
  }
  .nav-container {
    width: 100%;
    max-width: none;
    flex-direction: column;
    align-items: stretch;
    justify-content: flex-start;
    padding: 70px 0 20px;
  }
  .nav-link {
    padding: 14px 25px;
    font-size: 1rem;
    color: var(--primary-color);
    border-bottom: 1px solid rgba(38, 169, 224, 0.1);
    text-align: left;
    font-weight: 600;
    border-left: 4px solid transparent;
    border-radius: 0;
  }
  .nav-link:hover, .nav-link.active {
    background: #E6F5FB;
    border-bottom-color: var(--primary-color);
    color: var(--primary-color);
    border-left-color: var(--primary-color);
  }
  .nav-link:first-child {
    border-top: 1px solid rgba(38, 169, 224, 0.1);
  }
  .nav-home {
    padding-top: 15px;
  }
  .mobile-menu-overlay.active {
    display: block;
    background: rgba(0, 0, 0, 0.5);
    z-index: 999;
    width: 100%;
    height: 100%;
  }
  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;
  }
}
.site-footer {
  background: #1B7FA3;
  background: linear-gradient(180deg, #1B7FA3, #0F4C6E);
  color: #DDEFF7;
  padding: 60px 0 0;
  margin-top: 40px;
}
.footer-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 25px;
}
.footer-grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr 1.2fr;
  gap: 40px;
  padding-bottom: 50px;
}
.footer-logo {
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--secondary-color);
  display: inline-block;
  margin-bottom: 15px;
}
.footer-description {
  font-size: 0.9rem;
  line-height: 1.7;
  opacity: 0.85;
}
.footer-heading {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--secondary-color);
  margin-bottom: 15px;
  text-transform: uppercase;
  letter-spacing: 0.8px;
}
.footer-nav li a {
  color: #DDEFF7;
  font-size: 0.9rem;
  line-height: 2.2;
  transition: all 0.3s ease;
  opacity: 0.85;
}
.footer-nav li a:hover {
  color: var(--secondary-color);
  opacity: 1;
  padding-left: 4px;
}
.copyright-bar {
  border-top: 1px solid rgba(255, 255, 255, 0.15);
  padding: 20px 0;
  text-align: center;
  font-size: 0.9rem;
  color: rgba(255, 255, 255, 0.85);
}
@media (max-width: 768px) {
  .footer-grid {
    grid-template-columns: 1fr;
    gap: 30px;
    text-align: center;
    padding-bottom: 30px;
  }
  .footer-column {
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    padding-bottom: 20px;
  }
  .footer-column:last-child {
    border-bottom: none;
    padding-bottom: 0;
  }
  .footer-nav {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 10px 20px;
  }
  .footer-nav li {
    margin: 0;
  }
  .copyright-bar {
    font-size: 0.8rem;
  }
}
/* 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;
}