/* Basic Reset and Global Styles */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
  -moz-text-size-adjust: 100%;
  text-size-adjust: 100%;
}

body {
  font-family: 'Inter', 'Helvetica Neue', Helvetica, Arial, sans-serif;
  line-height: 1.6;
  color: #333;
  background-color: #f8f9fa;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 15px;
}

.flex-container {
  display: flex;
}

.align-items-center {
  align-items: center;
}

.justify-content-between {
  justify-content: space-between;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  font-family: 'Montserrat', sans-serif;
  margin-bottom: 0.5em;
  color: #212529;
}

p {
  margin-bottom: 1em;
}

a {
  color: #007bff;
  text-decoration: none;
  transition: color 0.3s ease, text-decoration 0.3s ease;
}

a:hover, a:focus {
  color: #0056b3;
  text-decoration: underline;
}

.btn {
  display: inline-block;
  font-weight: 600;
  text-align: center;
  vertical-align: middle;
  user-select: none;
  border: 1px solid transparent;
  padding: 0.75rem 1.5rem;
  font-size: 1rem;
  line-height: 1.5;
  border-radius: 0.3rem;
  transition: color 0.15s ease-in-out, background-color 0.15s ease-in-out, border-color 0.15s ease-in-out, box-shadow 0.15s ease-in-out;
  cursor: pointer;
}

.btn-primary {
  color: #fff;
  background-color: #007bff;
  border-color: #007bff;
}

.btn-primary:hover {
  color: #fff;
  background-color: #0056b3;
  border-color: #004085;
}

.btn-secondary {
  color: #007bff;
  background-color: transparent;
  border-color: #007bff;
}

.btn-secondary:hover {
  color: #fff;
  background-color: #007bff;
  border-color: #007bff;
}

/* Utility Classes */
.list-inline {
  list-style: none;
  padding: 0;
  margin: 0;
}

.list-inline li {
  display: inline-block;
  margin-left: 15px;
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* Header Specific Styles (example) */
.site-header {
  background-color: #fff;
  box-shadow: 0 2px 4px rgba(0,0,0,.08);
  position: sticky;
  top: 0;
  z-index: 1000;
}

.header-top-bar {
  background-color: #f1f1f1;
  padding: 8px 0;
  font-size: 0.85rem;
  color: #555;
}

.site-branding .site-logo {
  height: 40px;
  width: auto;
}

.primary-nav .nav-menu {
  list-style: none;
  padding: 0;
  margin: 0;
}

.primary-nav .nav-menu > li {
  display: inline-block;
  position: relative;
  margin-left: 30px;
}

.primary-nav .nav-menu > li > a {
  display: block;
  padding: 20px 0;
  color: #333;
  font-weight: 600;
}

.primary-nav .nav-menu > li > a:hover {
  color: #007bff;
}

.primary-nav .sub-menu {
  display: none;
  position: absolute;
  background-color: #fff;
  box-shadow: 0 4px 8px rgba(0,0,0,.1);
  list-style: none;
  min-width: 200px;
  z-index: 999;
  padding: 10px 0;
  border-radius: 0.3rem;
}

.primary-nav .menu-item-has-children:hover > .sub-menu {
  display: block;
}

.primary-nav .sub-menu li a {
  padding: 10px 20px;
  display: block;
  color: #555;
  white-space: nowrap;
}

.primary-nav .sub-menu li a:hover {
  background-color: #f8f9fa;
  color: #007bff;
}

.menu-toggle {
  display: none; /* Hidden on desktop */
}

/* Footer Specific Styles (example) */
.site-footer {
  background-color: #212529;
  color: #f8f9fa;
  padding: 60px 0 20px;
  font-size: 0.9rem;
}

.site-footer a {
  color: #adb5bd;
}

.site-footer a:hover {
  color: #fff;
}

.site-footer .footer-logo {
  height: 32px;
  margin-bottom: 20px;
}

.site-footer .grid-layout {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 30px;
  margin-bottom: 40px;
}

.site-footer .footer-heading {
  color: #fff;
  font-size: 1.1rem;
  margin-bottom: 20px;
  position: relative;
}

.site-footer .footer-heading::after {
  content: '';
  display: block;
  width: 40px;
  height: 2px;
  background-color: #007bff;
  margin-top: 10px;
}

.site-footer ul {
  list-style: none;
  padding: 0;
}

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

.site-footer .social-links a {
  display: inline-block;
  width: 36px;
  height: 36px;
  line-height: 36px;
  text-align: center;
  background-color: #343a40;
  color: #fff;
  border-radius: 50%;
  margin-right: 10px;
  transition: background-color 0.3s ease;
}

.site-footer .social-links a:hover {
  background-color: #007bff;
}

.site-footer address p {
  margin-bottom: 5px;
}

.site-footer .newsletter-form {
  display: flex;
  margin-top: 15px;
}

.site-footer .newsletter-form input[type="email"] {
  flex-grow: 1;
  padding: 10px 15px;
  border: 1px solid #495057;
  border-radius: 0.3rem 0 0 0.3rem;
  background-color: #343a40;
  color: #fff;
  outline: none;
}

.site-footer .newsletter-form input[type="email"]::placeholder {
  color: #adb5bd;
}

.site-footer .newsletter-form .btn {
  border-radius: 0 0.3rem 0.3rem 0;
  padding: 10px 20px;
  white-space: nowrap;
}

.footer-bottom-bar {
  border-top: 1px solid #343a40;
  padding-top: 20px;
  margin-top: 40px;
  text-align: center;
}

.footer-bottom-bar .copyright-info {
  margin-bottom: 0;
  font-size: 0.8rem;
  color: #adb5bd;
}

.footer-bottom-bar .footer-legal-nav .list-inline li {
  margin-left: 20px;
}

/* Responsive Adjustments (example) */
@media (max-width: 992px) {
  .primary-nav .nav-menu {
    display: none;
    flex-direction: column;
    position: absolute;
    top: 100%;
    left: 0;
    width: 100%;
    background-color: #fff;
    box-shadow: 0 4px 8px rgba(0,0,0,.1);
    border-top: 1px solid #eee;
  }

  .primary-nav .nav-menu.active {
    display: flex;
  }

  .primary-nav .nav-menu > li {
    display: block;
    margin: 0;
    border-bottom: 1px solid #eee;
  }

  .primary-nav .nav-menu > li:last-child {
    border-bottom: none;
  }

  .primary-nav .nav-menu > li > a {
    padding: 15px 20px;
  }

  .primary-nav .menu-item-has-children:hover > .sub-menu,
  .primary-nav .menu-item-has-children.active > .sub-menu {
    position: static;
    box-shadow: none;
    border-top: 1px solid #eee;
    padding-left: 20px;
    border-radius: 0;
  }

  .menu-toggle {
    display: block;
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    padding: 10px;
    position: relative;
    width: 40px;
    height: 40px;
  }

  .menu-toggle .icon-bar {
    display: block;
    width: 25px;
    height: 3px;
    background-color: #333;
    margin: 5px 0;
    transition: all 0.3s ease;
  }

  .site-header .header-actions {
    display: none; /* Hide actions on smaller screens for simplicity, or move to menu */
  }

  .site-footer .grid-layout {
    grid-template-columns: 1fr;
  }

  .footer-bottom-bar .flex-container {
    flex-direction: column;
    text-align: center;
  }

  .footer-bottom-bar .copyright-info {
    margin-bottom: 15px;
  }

  .footer-bottom-bar .footer-legal-nav .list-inline li {
    margin: 0 10px;
  }
}

@media (max-width: 768px) {
  .header-top-bar .top-bar-nav {
    display: none;
  }

  .header-top-bar .flex-container {
    justify-content: center;
  }

  .site-branding {
    flex-grow: 1;
  }

  .search-overlay .search-form {
    width: 90%;
  }
}

/* Icon placeholders (replace with actual font icons or SVGs) */
.icon-facebook::before { content: 'f'; font-family: 'Font Awesome 5 Brands'; }
.icon-twitter::before { content: 't'; font-family: 'Font Awesome 5 Brands'; }
.icon-linkedin::before { content: 'l'; font-family: 'Font Awesome 5 Brands'; }
.icon-instagram::before { content: 'i'; font-family: 'Font Awesome 5 Brands'; }
.icon-youtube::before { content: 'y'; font-family: 'Font Awesome 5 Brands'; }
.icon-search::before { content: 's'; font-family: 'Font Awesome 5 Free'; }
/* 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;
  }
}