:root {
    --primary-color: #2b87ff;
    --text-color: #333;
    --bg-gray: #f5f5f5;
    --border-color: #e5e5e5;
}

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

body {
    font-family: 'Microsoft YaHei', sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background: var(--bg-gray);
}

.navbar {
    background: #fff;
    padding: 0;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
}

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

.logo-link {
    text-decoration: none;
    display: block;
    padding: 0.5rem 0;
    transition: all 0.3s ease;
}

.logo-link h3 {
    font-size: 1.5rem;
    color: var(--primary-color);
    margin: 0;
    font-weight: 600;
}

.logo-link:hover h3 {
    color: #1a6cd1;
    transform: translateY(-1px);
}

.menu-toggle {
    display: none;
    flex-direction: column;
    justify-content: space-between;
    width: 30px;
    height: 21px;
    background: transparent;
    border: none;
    cursor: pointer;
    padding: 0;
    box-sizing: border-box;
}

.menu-toggle span {
    width: 100%;
    height: 3px;
    background-color: var(--primary-color);
    border-radius: 3px;
    transition: all 0.3s ease;
}

.main-nav {
    display: flex;
    list-style: none;
    gap: 2rem;
    margin: 0;
    padding: 0;
}

.main-nav a {
    text-decoration: none;
    color: var(--text-color);
    font-weight: 500;
    padding: 0.5rem 0;
    transition: color 0.3s ease;
}

.main-nav a:hover {
    color: var(--primary-color);
}

.banner {
    background: var(--primary-color);
    color: white;
    text-align: center;
    padding: 2rem;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0.5rem;
}

.resource-section {
    background: white;
    padding: 2rem;
    border-radius: 8px;
    margin-bottom: 2rem;
}

.resource-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-top: 1.5rem;
}

.resource-category h4 {
    color: var(--primary-color);
    margin-bottom: 1rem;
    padding-bottom: 0.5rem;
    border-bottom: 2px solid var(--primary-color);
}

.resource-category ul {
    list-style: none;
}

.resource-category li {
    margin-bottom: 0.5rem;
}

.resource-category a {
    text-decoration: none;
    color: var(--text-color);
    display: block;
    padding: 0.5rem 0;
    transition: all 0.3s ease;
}

.resource-category a:hover {
    color: var(--primary-color);
    padding-left: 10px;
}

.news-section {
    background: white;
    padding: 2rem;
    border-radius: 8px;
    margin-bottom: 2rem;
}

.news-item {
    padding: 1rem 0;
    border-bottom: 1px solid var(--border-color);
}

.news-item h4 a {
    text-decoration: none;
    color: var(--text-color);
    transition: color 0.3s ease;
}

.news-item h4 a:hover {
    color: var(--primary-color);
}

.news-item p {
    color: #666;
    font-size: 0.9rem;
    margin-top: 0.5rem;
}

.hot-section {
    background: white;
    padding: 2rem;
    border-radius: 8px;
}

.hot-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
    margin-top: 1.5rem;
}

.hot-item {
    text-align: center;
    position: relative;
    padding: 1rem;
    transition: all 0.3s ease;
}

.hot-item a {
    text-decoration: none;
    color: var(--text-color);
    display: block;
}

.hot-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
}

.hot-item img {
    width: 100%;
    height: 200px;
    object-fit: cover;
    border-radius: 8px;
    margin-bottom: 1rem;
    transition: transform 0.3s ease;
}

.hot-item h4 {
    font-size: 1.2rem;
    margin: 0.5rem 0;
    color: var(--text-color);
}

.hot-item p {
    color: #666;
    font-size: 0.9rem;
}

.hot-item img:hover {
    transform: scale(1.02);
    transition: transform 0.3s ease;
    box-shadow: 0 4px 15px rgba(0,0,0,0.1);
}

.hot-item img:not([src]), 
.hot-item img[src=""], 
.hot-item img[src="error"] {
    background-color: #f5f5f5;
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 200px;
}

footer {
    background: #333;
    color: white;
    padding: 3rem 5% 1rem;
    margin-top: 3rem;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.footer-section ul {
    list-style: none;
    margin-top: 1rem;
}

.footer-section a {
    color: white;
    text-decoration: none;
    transition: color 0.3s ease;
}

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

.copyright {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid #555;
}

@media (max-width: 768px) {
    .menu-toggle {
        display: flex;
    }

    .main-nav {
        flex-direction: column;
        width: 100%;
        gap: 0;
        display: none;
        padding: 1rem 0;
    }

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

    .main-nav li {
        width: 100%;
        text-align: center;
    }

    .main-nav a {
        display: block;
        padding: 0.8rem 0;
        border-top: 1px solid #eee;
    }

    .nav-container {
        padding: 1rem;
    }

    .hot-item img {
        height: 180px;
    }
    
    .hot-grid {
        grid-template-columns: 1fr;
    }

    .hot-item:hover {
        transform: none;
    }
    
    .resource-category a:hover {
        padding-left: 5px;
    }

    .logo-link h3 {
        font-size: 1.3rem;
    }
}

@keyframes slideDown {
    from {
        opacity: 0;
        transform: translateY(-10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.main-nav.active {
    animation: slideDown 0.3s ease forwards;
}

.breadcrumb a {
    color: var(--primary-color);
    text-decoration: none;
    transition: color 0.3s ease;
}

.breadcrumb a:hover {
    color: #1a6cd1;
}

.resource-btn {
    display: inline-block;
    padding: 0.8rem 1.5rem;
    background: var(--primary-color);
    color: white;
    text-decoration: none;
    border-radius: 4px;
    transition: all 0.3s ease;
}

.resource-btn:hover {
    background-color: #1a6cd1;
    transform: translateY(-2px);
    box-shadow: 0 4px 10px rgba(0,0,0,0.1);
}