:root {
  --primary-color: #26A9E0;
  --secondary-color: #FFFFFF;
  --login-color: #EA7C07;
  --bg-color: #FFFFFF;
  --dark-color: #0f1c2e;
  --header-offset: 120px;
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  background-color: var(--bg-color);
  color: #333333;
  padding-top: var(--header-offset);
}

/* ===== Header Styles ===== */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
  background-color: #1a2433;
}

/* Top Bar */
.header-top {
  background: linear-gradient(90deg, #16222e 0%, #1a2b3d 100%);
  width: 100%;
}

.header-container {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 12px 25px;
  min-height: 68px;
}

.logo {
  font-size: 32px;
  font-weight: 900;
  color: #ffffff;
  text-decoration: none;
  letter-spacing: 1px;
  display: inline-block;
  text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.3);
}

.logo:hover {
  color: var(--primary-color);
}

.desktop-nav-buttons {
  display: flex;
  gap: 12px;
  align-items: center;
}

.btn {
  display: inline-block;
  padding: 10px 24px;
  border-radius: 6px;
  font-weight: 700;
  font-size: 15px;
  text-decoration: none;
  text-align: center;
  border: none;
  cursor: pointer;
  transition: all 0.3s ease;
  line-height: 1.4;
}

.btn-register {
  background-color: #f3a712;
  color: #1a2433;
  box-shadow: 0 3px 8px rgba(243, 167, 18, 0.3);
}

.btn-register:hover {
  background-color: #d4940a;
  transform: translateY(-2px);
}

.btn-login {
  background-color: var(--login-color);
  color: #ffffff;
  box-shadow: 0 3px 8px rgba(234, 124, 7, 0.3);
}

.btn-login:hover {
  background-color: #d26a03;
  transform: translateY(-2px);
}

/* Main Navigation Bar */
.main-nav {
  background: linear-gradient(180deg, #f0f7fb 0%, #e2f0f7 100%);
  border-top: 1px solid #c4e4f2;
  display: flex;
  flex-direction: row;
  position: static;
  min-height: 52px;
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  flex-direction: row;
  justify-content: center;
  align-items: center;
  padding: 6px 20px;
  width: 100%;
}

.nav-menu {
  list-style-type: none;
  display: flex;
  flex-wrap: wrap;
  gap: 5px;
  justify-content: center;
}

.nav-menu li {
  margin: 0 2px;
}

.nav-link {
  display: block;
  padding: 8px 16px;
  color: #1a2433;
  font-weight: 600;
  font-size: 14px;
  text-decoration: none;
  border-radius: 4px;
  transition: all 0.3s ease;
  white-space: nowrap;
}

.nav-link:hover {
  background-color: var(--primary-color);
  color: #ffffff;
}

.nav-link.active {
  background-color: var(--primary-color);
  color: #ffffff;
}

/* Hamburger Menu - hidden on desktop */
.hamburger-menu {
  display: none;
}

/* Mobile overlay - hidden on desktop */
.mobile-menu-overlay {
  display: none;
}

/* Mobile nav buttons - hidden on desktop */
.mobile-nav-buttons {
  display: none;
}

/* ===== Footer Styles ===== */
.site-footer {
  background: linear-gradient(180deg, #1a2433 0%, #0f1c2e 100%);
  color: #cdd7e0;
  padding-top: 50px;
  margin-top: 50px;
}

.footer-container {
  max-width: 1200px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1.5fr 1fr 1.2fr;
  gap: 40px;
  padding: 0 25px 40px;
}

.footer-brand {
  text-align: left;
}

.footer-logo {
  font-size: 42px;
  font-weight: 900;
  color: #ffffff;
  text-decoration: none;
  letter-spacing: 1px;
  display: inline-block;
  margin-bottom: 18px;
  text-shadow: 2px 2px 8px rgba(0, 0, 0, 0.5);
}

.footer-description {
  font-size: 14px;
  line-height: 1.7;
  color: #9aabbc;
  max-width: 400px;
}

.footer-heading {
  font-size: 16px;
  font-weight: 700;
  color: var(--primary-color);
  margin-bottom: 18px;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.footer-nav {
  list-style-type: none;
  padding: 0;
}

.footer-nav li {
  margin-bottom: 10px;
}

.footer-nav a {
  color: #a8b8c8;
  text-decoration: none;
  font-size: 14px;
  transition: color 0.3s ease;
}

.footer-nav a:hover {
  color: var(--primary-color);
  text-decoration: underline;
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding: 18px 25px;
  text-align: center;
  background-color: rgba(0, 0, 0, 0.3);
}

.footer-bottom p {
  font-size: 14px;
  color: #8899a8;
}

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

  body {
    overflow-x: hidden;
  }

  /* Header container spans full width on mobile */
  .header-container {
    width: 100%;
    max-width: none;
    padding-left: 15px;
    padding-right: 15px;
    min-height: 60px;
  }

  .nav-container {
    width: 100%;
    max-width: none;
    padding-left: 15px;
    padding-right: 15px;
  }

  /* Show hamburger menu on mobile */
  .hamburger-menu {
    display: flex;
    flex-direction: column;
    justify-content: center;
    gap: 5px;
    width: 40px;
    height: 40px;
    background: transparent;
    border: none;
    cursor: pointer;
    padding: 8px;
    order: 1;
    z-index: 1002;
  }

  .bar {
    display: block;
    width: 25px;
    height: 3px;
    margin: 2px 0;
    background-color: #ffffff;
    border-radius: 4px;
    transition: transform 0.3s ease, opacity 0.3s ease;
  }

  .hamburger-menu.active .bar:nth-child(1) {
    transform: translateY(7px) rotate(45deg);
  }

  .hamburger-menu.active .bar:nth-child(2) {
    opacity: 0;
  }

  .hamburger-menu.active .bar:nth-child(3) {
    transform: translateY(-7px) rotate(-45deg);
  }

  /* Logo centered on mobile */
  .logo {
    order: 2;
    flex: 1;
    text-align: center;
    font-size: 28px;
    display: block;
  }

  .header-container {
    flex-direction: row;
  }

  .desktop-nav-buttons {
    display: none;
  }

  /* Main nav hidden on mobile, becomes slide-in drawer */
  .main-nav {
    display: none;
    flex-direction: column;
    position: fixed;
    top: 0;
    left: 0;
    bottom: 0;
    width: 280px;
    background: #1a2433;
    z-index: 1001;
    transform: translateX(-100%);
    transition: transform 0.3s ease;
    border-top: none;
    box-shadow: 2px 0 15px rgba(0, 0, 0, 0.2);
  }

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

  .nav-container {
    flex-direction: column;
    align-items: flex-start;
    justify-content: flex-start;
    padding: 20px 0;
    margin-top: 60px;
  }

  .nav-menu {
    flex-direction: column;
    width: 100%;
  }

  .nav-menu li {
    width: 100%;
  }

  .nav-link {
    padding: 12px 25px;
    color: #ffffff;
    width: 100%;
    font-size: 15px;
    border-radius: 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
  }

  .nav-link:hover {
    background-color: rgba(38, 169, 224, 0.3);
    color: #ffffff;
  }

  .nav-link.active {
    background-color: rgba(38, 169, 224, 0.5);
    color: #ffffff;
  }

  .hamburger-menu.active {
    position: fixed;
    top: 10px;
    left: 15px;
  }

  .hamburger-menu.active .bar {
    background-color: #ffffff;
  }

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

  .mobile-menu-overlay.visible {
    display: block;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: rgba(0, 0, 0, 0.5);
    z-index: 1000;
  }

  /* Mobile nav buttons */
  .mobile-nav-buttons {
    display: flex;
    justify-content: center;
    background-color: #1a2433;
    border-top: 1px solid rgba(255, 255, 255, 0.05);
    padding: 0;
    min-height: 48px;
  }

  .mobile-nav-buttons-container {
    width: 100%;
    max-width: none;
    display: flex;
    justify-content: center;
    gap: 10px;
    align-items: center;
  }

  .mobile-nav-buttons .btn {
    flex: 1;
    max-width: 180px;
    margin: 6px 5px;
    padding: 8px 20px;
    font-size: 14px;
  }

  /* Footer mobile */
  .footer-container {
    grid-template-columns: 1fr;
    gap: 25px;
    padding: 20px 20px 30px;
    text-align: center;
  }

  .footer-brand {
    text-align: center;
  }

  .footer-description {
    margin: 0 auto;
  }

  .site-footer {
    padding-top: 30px;
  }

  .footer-bottom {
    padding: 15px 20px;
  }

  .page-content img {
    max-width: 100% !important;
    height: auto !important;
    display: block;
  }

  .page-content {
    overflow-x: hidden;
    max-width: 100%;
  }
}

/* Content spacing */
body {
  padding-top: var(--header-offset);
}
/* 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;
}