/* 全局样式 */
:root {
    --primary-color: #0056b3; /* A strong blue for primary elements */
    --background-color: #f0f2f5; /* Light grey background */
    --card-background-color: #ffffff; /* White cards */
    --card-hover-background-color: #f7f7f7; /* Slightly off-white for hover */
    --text-color: #333333; /* Dark grey for text */
    --muted-text-color: #666666; /* Lighter grey for muted text */
    --header-color: #1a1a1a; /* Almost black for the main header */
    --border-color: #e0e0e0; /* Light grey for borders */
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
    margin: 0;
    padding: 0;
    background-color: var(--background-color); /* Fallback */
    background-image: linear-gradient(rgba(255, 255, 255, 0.55), rgba(255, 255, 255, 0.55)), url('https://images.901088.xyz/random_image');
    background-size: cover;
    background-position: center center;
    background-attachment: fixed;
    color: var(--text-color);
    line-height: 1.6;
}

/* 头部样式 */
header {
    text-align: center;
    padding: 40px 20px;
    background-color: transparent;
}

header h1 {
    font-size: 2.5rem;
    color: var(--header-color);
    font-weight: 700;
    margin: 0 0 20px 0; /* Add margin to the bottom */
}

/* Navigation Styles */
.main-nav {
    display: flex;
    justify-content: center;
    gap: 10px;
}

.main-nav a {
    text-decoration: none;
    color: var(--primary-color);
    background-color: transparent;
    padding: 10px 20px;
    border-radius: 20px;
    border: 1px solid var(--primary-color);
    transition: background-color 0.3s, color 0.3s;
    font-weight: 500;
}

.main-nav a:hover, .main-nav a.active {
    background-color: var(--primary-color);
    color: white;
}

/* 导航容器 */
#navigation-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
}

/* 链接分组 */
.group-container {
    margin-bottom: 40px;
}

.group-container h2 {
    font-size: 1.8rem;
    color: var(--primary-color);
    border-bottom: 2px solid var(--border-color);
    padding-bottom: 10px;
    margin-bottom: 20px;
}

.links-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 20px;
}

/* 卡片样式 */
.link-card {
    background-color: var(--card-background-color);
    border-radius: 8px;
    border: 1px solid var(--border-color);
    overflow: hidden;
    text-decoration: none;
    color: var(--text-color);
    transition: transform 0.3s ease, background-color 0.3s ease;
    display: flex;
    flex-direction: column;
}

.link-card:hover {
    transform: translateY(-5px);
    background-color: var(--card-hover-background-color);
}

.card-content {
    padding: 20px;
    display: flex;
    align-items: center;
}

.card-logo {
    width: 40px;
    height: 40px;
    margin-right: 15px;
    flex-shrink: 0;
}

.card-text {
    flex-grow: 1;
}

.card-name {
    font-size: 1.2rem;
    font-weight: 600;
    color: var(--primary-color);
    margin: 0;
}

.card-description {
    font-size: 0.9rem;
    color: var(--muted-text-color);
    margin-top: 5px;
}

/* 响应式设计 */
@media (max-width: 768px) {
    header h1 {
        font-size: 2rem;
    }

    .group-container h2 {
        font-size: 1.5rem;
    }

    .links-grid {
        grid-template-columns: 1fr;
    }
}