/* 全局样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: "Microsoft YaHei", "微软雅黑", Arial, sans-serif;
    line-height: 1.6;
    color: #333;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* 头部样式 */
header {
    background: rgba(255, 255, 255, 0.95);
    padding: 40px 0;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    margin-bottom: 40px;
}

header h1 {
    text-align: center;
    font-size: 2.5em;
    color: #667eea;
    margin-bottom: 10px;
}

.subtitle {
    text-align: center;
    color: #666;
    font-size: 1.1em;
}

/* 统计卡片 */
.stats {
    display: flex;
    justify-content: center;
    gap: 30px;
    margin-bottom: 40px;
    flex-wrap: wrap;
}

.stat-item {
    background: white;
    padding: 20px 40px;
    border-radius: 10px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    text-align: center;
}

.stat-number {
    display: block;
    font-size: 2em;
    font-weight: bold;
    color: #667eea;
}

.stat-label {
    display: block;
    color: #666;
    margin-top: 5px;
}

/* 笔记网格 */
.notes-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 25px;
    margin-bottom: 40px;
}

/* 笔记卡片 */
.note-card {
    background: white;
    border-radius: 10px;
    padding: 25px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.note-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 4px;
    height: 100%;
    background: linear-gradient(to bottom, #667eea, #764ba2);
    transition: width 0.3s ease;
}

.note-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 15px rgba(0, 0, 0, 0.2);
}

.note-card:hover::before {
    width: 8px;
}

.note-link {
    text-decoration: none;
    color: inherit;
    display: block;
}

.note-title {
    font-size: 1.3em;
    color: #333;
    margin-bottom: 12px;
    transition: color 0.3s ease;
}

.note-card:hover .note-title {
    color: #667eea;
}

.note-summary {
    color: #666;
    margin-bottom: 15px;
    line-height: 1.6;
}

.note-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    color: #999;
    font-size: 0.9em;
}

.note-date {
    background: #f0f0f0;
    padding: 4px 12px;
    border-radius: 20px;
}

.note-icon {
    font-size: 1.2em;
    color: #667eea;
    transition: transform 0.3s ease;
}

.note-card:hover .note-icon {
    transform: translateX(5px);
}

/* 底部 */
footer {
    background: rgba(0, 0, 0, 0.1);
    color: white;
    text-align: center;
    padding: 30px 0;
    margin-top: 60px;
}

/* 响应式设计 */
@media (max-width: 768px) {
    header h1 {
        font-size: 1.8em;
    }
    
    .stats {
        gap: 15px;
    }
    
    .stat-item {
        padding: 15px 25px;
    }
    
    .stat-number {
        font-size: 1.5em;
    }
    
    .notes-grid {
        grid-template-columns: 1fr;
    }
}

/* 动画 */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.note-card {
    animation: fadeIn 0.5s ease forwards;
}

.note-card:nth-child(1) { animation-delay: 0.1s; }
.note-card:nth-child(2) { animation-delay: 0.2s; }
.note-card:nth-child(3) { animation-delay: 0.3s; }
.note-card:nth-child(4) { animation-delay: 0.4s; }
.note-card:nth-child(5) { animation-delay: 0.5s; }
.note-card:nth-child(6) { animation-delay: 0.6s; }