/* Shared CSS for the entire site */
:root {
    --primary-color: #007bff;
    --secondary-color: #6c757d;
    --success-color: #28a745;
    --info-color: #17a2b8;
    --warning-color: #ffc107;
    --danger-color: #dc3545;
    --light-color: #f8f9fa;
    --dark-color: #343a40;
    --text-color: #333;
    --background-color: #fff;
    --border-color: #dee2e6;
    --font-family-sans-serif: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol";
    --font-family-monospace: SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;
}

body {
    font-family: var(--font-family-sans-serif);
    line-height: 1.6;
    margin: 0;
    padding: 0;
    color: var(--text-color);
    background-color: var(--background-color);
}

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

a {
    color: var(--primary-color);
    text-decoration: none;
}

a:hover {
    text-decoration: underline;
}

.btn {
    display: inline-block;
    font-weight: 400;
    color: #212529;
    text-align: center;
    vertical-align: middle;
    -webkit-user-select: none;
    -moz-user-select: none;
    -ms-user-select: none;
    user-select: none;
    background-color: transparent;
    border: 1px solid transparent;
    padding: .375rem .75rem;
    font-size: 1rem;
    line-height: 1.5;
    border-radius: .25rem;
    transition: color .15s ease-in-out, background-color .15s ease-in-out, border-color .15s ease-in-out, box-shadow .15s ease-in-out;
}

.btn-primary {
    color: #fff;
    background-color: var(--primary-color);
    border-color: var(--primary-color);
}

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

.btn-secondary {
    color: #fff;
    background-color: var(--secondary-color);
    border-color: var(--secondary-color);
}

.btn-secondary:hover {
    color: #fff;
    background-color: #545b62;
    border-color: #545b62;
}

/* Header specific styles */
.main-header {
    background-color: var(--dark-color);
    color: var(--light-color);
    padding: 1rem 0;
    border-bottom: 3px solid var(--primary-color);
}

.main-header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
}

.main-header .logo img {
    height: 40px;
}

.main-nav .nav-list {
    list-style: none;
    margin: 0;
    padding: 0;
    display: flex;
}

.main-nav .nav-item {
    position: relative;
    margin-left: 20px;
}

.main-nav .nav-link {
    color: var(--light-color);
    padding: 10px 0;
    display: block;
    white-space: nowrap;
}

.main-nav .nav-link:hover {
    color: var(--primary-color);
    text-decoration: none;
}

.main-nav .dropdown-menu {
    display: none;
    position: absolute;
    background-color: var(--dark-color);
    min-width: 160px;
    box-shadow: 0px 8px 16px 0px rgba(0,0,0,0.2);
    z-index: 1;
    list-style: none;
    padding: 10px 0;
    margin: 0;
    border-radius: .25rem;
}

.main-nav .nav-item.dropdown:hover .dropdown-menu {
    display: block;
}

.main-nav .dropdown-menu li a {
    color: var(--light-color);
    padding: 8px 15px;
    text-decoration: none;
    display: block;
    white-space: nowrap;
}

.main-nav .dropdown-menu li a:hover {
    background-color: var(--primary-color);
    color: #fff;
}

.menu-toggle {
    display: none; /* Hidden on desktop */
    background: none;
    border: none;
    color: var(--light-color);
    font-size: 1.5rem;
    cursor: pointer;
}

.icon-bar {
    display: block;
    width: 25px;
    height: 3px;
    background-color: var(--light-color);
    margin: 5px 0;
}

.header-actions {
    display: flex;
    align-items: center;
    gap: 10px;
}

.search-form {
    display: flex;
}

.search-form input {
    border: 1px solid var(--border-color);
    padding: 8px 12px;
    border-radius: .25rem 0 0 .25rem;
    outline: none;
}

.search-form button {
    background-color: var(--primary-color);
    color: #fff;
    border: 1px solid var(--primary-color);
    padding: 8px 12px;
    border-radius: 0 .25rem .25rem 0;
    cursor: pointer;
    transition: background-color .15s ease-in-out;
}

.search-form button:hover {
    background-color: #0056b3;
    border-color: #0056b3;
}

.announcement-bar {
    background-color: var(--warning-color);
    color: var(--dark-color);
    padding: 0.5rem 0;
    text-align: center;
    font-size: 0.9rem;
}

.announcement-bar .announcement-link {
    color: var(--dark-color);
    font-weight: bold;
    text-decoration: underline;
}

.sub-header {
    background-color: #f0f0f0;
    color: #555;
    padding: 1rem 0;
    text-align: center;
    border-bottom: 1px solid #e0e0e0;
}

/* Footer specific styles */
.main-footer {
    background-color: var(--dark-color);
    color: var(--light-color);
    padding: 3rem 0;
    margin-top: 50px;
    font-size: 0.9rem;
}

.main-footer .footer-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
    margin-bottom: 2rem;
}

.main-footer h3 {
    color: var(--primary-color);
    margin-bottom: 1rem;
    font-size: 1.1rem;
}

.main-footer p {
    margin-bottom: 1rem;
}

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

.main-footer ul li {
    margin-bottom: 0.5rem;
}

.main-footer ul li a {
    color: var(--light-color);
}

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

.main-footer .social-links a {
    color: var(--light-color);
    font-size: 1.5rem;
    margin-right: 15px;
    transition: color 0.3s ease;
}

.main-footer .social-links a:hover {
    color: var(--primary-color);
}

.main-footer .contact-info p {
    display: flex;
    align-items: center;
    gap: 10px;
}

.main-footer .contact-info i {
    color: var(--primary-color);
}

.main-footer .newsletter form {
    display: flex;
    margin-top: 1rem;
}

.main-footer .newsletter input[type="email"] {
    flex-grow: 1;
    padding: 0.5rem 1rem;
    border: 1px solid var(--border-color);
    border-radius: .25rem 0 0 .25rem;
    outline: none;
}

.main-footer .newsletter .btn-subscribe {
    background-color: var(--primary-color);
    color: #fff;
    border: 1px solid var(--primary-color);
    padding: 0.5rem 1rem;
    border-radius: 0 .25rem .25rem 0;
    cursor: pointer;
    transition: background-color 0.3s ease;
}

.main-footer .newsletter .btn-subscribe:hover {
    background-color: #0056b3;
    border-color: #0056b3;
}

.footer-bottom {
    border-top: 1px solid #444;
    padding-top: 1.5rem;
    text-align: center;
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
}

.footer-bottom p {
    margin: 0;
}

.footer-bottom a {
    color: var(--primary-color);
}

.back-to-top {
    margin-top: 10px;
}

.back-to-top a {
    display: inline-flex;
    align-items: center;
    gap: 5px;
    color: var(--light-color);
}

.back-to-top a:hover {
    color: var(--primary-color);
    text-decoration: none;
}

/* Responsive adjustments */
@media (max-width: 768px) {
    .main-header .container {
        flex-direction: column;
        align-items: flex-start;
    }

    .main-nav {
        width: 100%;
        order: 3; /* Move nav below logo and actions */
    }

    .main-nav .nav-list {
        flex-direction: column;
        width: 100%;
        display: none; /* Hidden by default for mobile */
    }

    .main-nav .nav-list.active {
        display: flex; /* Show when active */
    }

    .main-nav .nav-item {
        margin: 0;
        border-bottom: 1px solid #444;
        width: 100%;
    }

    .main-nav .nav-link {
        padding: 10px 15px;
    }

    .main-nav .dropdown-menu {
        position: static;
        width: 100%;
        background-color: #444;
        box-shadow: none;
        border-radius: 0;
        padding-left: 20px;
    }

    .menu-toggle {
        display: block; /* Show on mobile */
        order: 2;
        margin-left: auto;
    }

    .header-actions {
        order: 1;
        width: 100%;
        justify-content: flex-end;
        margin-bottom: 10px;
    }

    .search-form {
        flex-grow: 1;
        margin-right: 10px;
    }

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

    .footer-bottom {
        flex-direction: column;
        gap: 10px;
    }
}
/* 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;
  }
}