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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    color: #374151;
    background: #ffffff;
    line-height: 1.6;
}

/* 容器 */
.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* 链接 */
a {
    color: #1e40af;
    text-decoration: none;
    transition: color 0.3s ease;
}

a:hover {
    color: #f97316;
}

/* 标题 */
h1, h2, h3, h4, h5, h6 {
    font-family: 'Poppins', sans-serif;
    font-weight: 600;
    line-height: 1.4;
}

h1 { font-size: 36px; }
h2 { font-size: 28px; }
h3 { font-size: 22px; }

/* 按钮 */
button, .btn {
    padding: 10px 20px;
    border: none;
    border-radius: 6px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
}

button:hover, .btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0,0,0,0.15);
}

/* 卡片 */
.card {
    background: white;
    border-radius: 8px;
    padding: 20px;
    border: 1px solid #e5e7eb;
    transition: all 0.3s ease;
}

.card:hover {
    box-shadow: 0 8px 24px rgba(0,0,0,0.1);
    transform: translateY(-4px);
}

/* 代码块 */
code {
    background: #f3f4f6;
    padding: 2px 6px;
    border-radius: 4px;
    font-family: 'Courier New', monospace;
    font-size: 14px;
}

pre {
    background: #1f2937;
    color: #e5e7eb;
    padding: 16px;
    border-radius: 8px;
    overflow-x: auto;
    margin: 16px 0;
}

pre code {
    background: none;
    padding: 0;
    color: #e5e7eb;
}

/* 表格 */
table {
    width: 100%;
    border-collapse: collapse;
    margin: 20px 0;
}

table th {
    background: #f3f4f6;
    padding: 12px;
    text-align: left;
    font-weight: 600;
    border-bottom: 2px solid #e5e7eb;
}

table td {
    padding: 12px;
    border-bottom: 1px solid #e5e7eb;
}

table tr:hover {
    background: #f9fafb;
}

/* 列表 */
ul, ol {
    margin: 16px 0;
    padding-left: 24px;
}

li {
    margin: 8px 0;
}

/* 引用 */
blockquote {
    border-left: 4px solid #1e40af;
    padding-left: 16px;
    margin: 16px 0;
    color: #6b7280;
    font-style: italic;
}

/* 图片 */
img {
    max-width: 100%;
    height: auto;
    border-radius: 8px;
    margin: 16px 0;
}

/* 响应式设计 */
@media (max-width: 768px) {
    h1 { font-size: 28px; }
    h2 { font-size: 22px; }
    h3 { font-size: 18px; }
    
    .container {
        padding: 0 16px;
    }
    
    nav {
        flex-direction: column;
        gap: 16px;
    }
}

/* 动画 */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.fade-in {
    animation: fadeIn 0.3s ease;
}

/* 工具类 */
.text-center { text-align: center; }
.text-muted { color: #6b7280; }
.mt-20 { margin-top: 20px; }
.mb-20 { margin-bottom: 20px; }
.p-20 { padding: 20px; }
.rounded { border-radius: 8px; }
.shadow { box-shadow: 0 4px 12px rgba(0,0,0,0.1); }