/* General Body Styles */
body {
    font-family: 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    margin: 0;
    padding: 0;
    color: #333;
    line-height: 1.6;
    background-color: #f8f9fa;
}

/* Container for overall layout */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 15px;
}

/* Header Styles */
.site-header {
    background-color: #fff;
    border-bottom: 1px solid #e0e0e0;
    padding: 15px 0;
    box-shadow: 0 2px 4px rgba(0,0,0,0.05);
    position: sticky;
    top: 0;
    z-index: 1000;
}

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

.branding {
    display: flex;
    align-items: center;
}

.branding .logo img {
    height: 40px;
    margin-right: 10px;
}

.branding .site-title {
    font-size: 1.8em;
    font-weight: 700;
    color: #0056b3;
}

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

.main-nav ul li {
    position: relative;
    margin-left: 25px;
}

.main-nav ul li a {
    text-decoration: none;
    color: #333;
    font-weight: 500;
    padding: 10px 0;
    display: block;
    transition: color 0.3s ease;
}

.main-nav ul li a:hover,
.main-nav ul li a:focus {
    color: #007bff;
}

.main-nav .dropdown {
    display: none;
    position: absolute;
    background-color: #fff;
    box-shadow: 0 8px 16px rgba(0,0,0,0.1);
    min-width: 200px;
    z-index: 1;
    list-style: none;
    padding: 10px 0;
    border-radius: 4px;
    top: 100%;
    left: 0;
}

.main-nav ul li:hover > .dropdown {
    display: block;
}

.main-nav .dropdown li {
    margin: 0;
}

.main-nav .dropdown li a {
    padding: 10px 20px;
    color: #555;
    white-space: nowrap;
}

.main-nav .dropdown li a:hover {
    background-color: #f1f1f1;
    color: #007bff;
}

.utility-nav {
    display: flex;
    align-items: center;
}

.utility-nav .btn {
    text-decoration: none;
    padding: 8px 15px;
    border-radius: 5px;
    margin-left: 10px;
    transition: background-color 0.3s ease, color 0.3s ease;
}

.utility-nav .btn-primary {
    background-color: #007bff;
    color: #fff;
    border: 1px solid #007bff;
}

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

.utility-nav .btn-secondary {
    background-color: #6c757d;
    color: #fff;
    border: 1px solid #6c757d;
}

.utility-nav .btn-secondary:hover {
    background-color: #5a6268;
    border-color: #545b62;
}

.menu-toggle {
    display: none; /* Hidden on desktop */
    background: none;
    border: none;
    font-size: 1.5em;
    cursor: pointer;
    margin-left: 15px;
}

/* Footer Styles */
.site-footer {
    background-color: #343a40;
    color: #f8f9fa;
    padding: 40px 0;
    font-size: 0.9em;
}

.site-footer a {
    color: #adb5bd;
    text-decoration: none;
}

.site-footer a:hover {
    color: #007bff;
    text-decoration: underline;
}

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

.footer-col h3 {
    color: #fff;
    font-size: 1.2em;
    margin-bottom: 15px;
}

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

.footer-col ul li {
    margin-bottom: 8px;
}

.footer-col.contact-info p {
    margin-bottom: 8px;
}

.social-links a {
    display: inline-block;
    margin-right: 10px;
}

.social-links img {
    width: 24px;
    height: 24px;
    filter: invert(70%) sepia(9%) saturate(271%) hue-rotate(175deg) brightness(97%) contrast(89%); /* Adjust for light color */
    transition: filter 0.3s ease;
}

.social-links a:hover img {
    filter: invert(47%) sepia(93%) saturate(2135%) hue-rotate(200deg) brightness(100%) contrast(100%); /* Blue on hover */
}

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

.newsletter input[type="email"] {
    flex-grow: 1;
    padding: 10px;
    border: 1px solid #555;
    border-radius: 4px 0 0 4px;
    background-color: #495057;
    color: #fff;
}

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

.newsletter button {
    padding: 10px 15px;
    background-color: #007bff;
    color: #fff;
    border: 1px solid #007bff;
    border-radius: 0 4px 4px 0;
    cursor: pointer;
    transition: background-color 0.3s ease, border-color 0.3s ease;
}

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

.copyright {
    text-align: center;
    margin-top: 30px;
    padding-top: 20px;
    border-top: 1px solid #495057;
    color: #adb5bd;
}

/* Responsive adjustments */
@media (max-width: 768px) {
    .main-nav ul {
        display: none;
        flex-direction: column;
        position: absolute;
        top: 70px; /* Adjust based on header height */
        left: 0;
        width: 100%;
        background-color: #fff;
        box-shadow: 0 8px 16px rgba(0,0,0,0.1);
        padding: 10px 0;
    }

    .main-nav ul.active {
        display: flex;
    }

    .main-nav ul li {
        margin: 0;
        border-bottom: 1px solid #f1f1f1;
    }

    .main-nav ul li:last-child {
        border-bottom: none;
    }

    .main-nav ul li a {
        padding: 15px 20px;
    }

    .main-nav .dropdown {
        position: static;
        box-shadow: none;
        border-top: 1px solid #f1f1f1;
        padding-left: 20px;
    }

    .menu-toggle {
        display: block;
    }

    .site-header .container {
        flex-wrap: wrap;
    }

    .branding {
        flex-grow: 1;
    }

    .utility-nav {
        order: 3; /* Move utility nav below branding and toggle */
        width: 100%;
        justify-content: center;
        margin-top: 15px;
    }
}
/* 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;
  }
}