/* 全局样式定义 */
body {
    margin: 0;
    font-family: 'Roboto', sans-serif;
    background: linear-gradient(135deg, #1E1E1E, #2C2C2C);
    color: #FFFFFF;
    line-height: 1.6;
}

.container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 20px;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
}

header {
    text-align: center;
    padding: 40px 0;
    background: linear-gradient(90deg, #00BFFF, #9400D3);
    color: #FFFFFF;
    font-size: 2rem;
    font-weight: bold;
    letter-spacing: 2px;
    position: relative;
}

header::after {
    content: '这是一个网页样式设计参考';
    position: absolute;
    bottom: 10px;
    right: 20px;
    font-size: 0.8rem;
    color: #F5F5F5;
    opacity: 0.7;
}

section {
    background-color: #2C2C2C;
    border-radius: 12px;
    box-shadow: 0 6px 12px rgba(0, 0, 0, 0.3);
    padding: 20px;
    transition: transform 0.3s ease-in-out;
}

section:hover {
    transform: translateY(-5px);
}

h2, h3, h4 {
    color: #00BFFF;
    font-weight: bold;
    margin-top: 0;
}

h2 {
    font-size: 2rem;
    text-transform: uppercase;
    letter-spacing: 1px;
}

p {
    font-size: 1rem;
    color: #F5F5F5;
    line-height: 1.8;
}

ul, ol {
    padding-left: 20px;
    color: #C0C0C0;
}

li {
    margin-bottom: 10px;
}

code {
    background-color: #333;
    color: #00FF00;
    padding: 5px 10px;
    border-radius: 5px;
    font-family: 'Courier New', monospace;
    font-size: 0.9rem;
}

pre {
    background-color: #333;
    padding: 15px;
    border-radius: 8px;
    overflow-x: auto;
}

table {
    width: 100%;
    border-collapse: collapse;
    margin: 20px 0;
    background-color: #333;
    color: #FFFFFF;
}

th, td {
    padding: 12px;
    text-align: left;
    border-bottom: 1px solid #444;
}

th {
    background-color: #00BFFF;
    color: #000;
    font-weight: bold;
}

.button-primary {
    background: linear-gradient(90deg, #00BFFF, #9400D3);
    color: #FFFFFF;
    border: none;
    padding: 12px 25px;
    font-size: 1rem;
    border-radius: 25px;
    cursor: pointer;
    transition: background 0.3s ease;
}

.button-primary:hover {
    background: linear-gradient(90deg, #0074D9, #6A0DAD);
}

.card {
    background: linear-gradient(135deg, #2C2C2C, #333);
    border-radius: 15px;
    padding: 20px;
    box-shadow: 0 4px 10px rgba(0, 0, 0, 0.4);
    text-align: center;
    transition: transform 0.3s ease;
}

.card img {
    width: 100px;
    height: 100px;
    object-fit: cover;
    border-radius: 50%;
    margin-bottom: 15px;
}

.card:hover {
    transform: scale(1.05);
}

.loader {
    border: 4px solid #f3f3f3;
    border-top: 4px solid #00BFFF;
    border-radius: 50%;
    width: 50px;
    height: 50px;
    animation: spin 2s linear infinite;
    margin: 20px auto;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

@media (max-width: 768px) {
    header {
        font-size: 1.5rem;
        padding: 20px 0;
    }

    h2 {
        font-size: 1.8rem;
    }

    p, li {
        font-size: 0.9rem;
    }

    .container {
        grid-template-columns: 1fr;
        gap: 20px;
    }

    pre {
        font-size: 0.8rem;
    }
}