/* 全局样式 */
body {
    margin: 0;
    font-family: 'Roboto', sans-serif;
    background: linear-gradient(135deg, #000033, #1a1aff);
    color: #ffffff;
    line-height: 1.6;
}

h1, h2, h3, h4 {
    font-family: 'Poppins', sans-serif;
    letter-spacing: 2px;
}

p {
    font-size: 1rem;
    line-height: 1.8;
    margin-bottom: 1.5rem;
}

a {
    color: #33ff99;
    text-decoration: none;
    transition: color 0.3s ease;
}

a:hover {
    color: #ffcc00;
}

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

/* 首页全屏沉浸式设计 */
.hero-section {
    height: 100vh;
    background: url('https://images.gptkong.com/demo/sample1.png') no-repeat center center, 
                linear-gradient(135deg, #000033, #1a1aff);
    background-size: cover;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    color: #ffffff;
}

.hero-section h1 {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.hero-section p {
    font-size: 1.5rem;
    max-width: 600px;
    margin: 0 auto;
}

/* 卡片布局与悬浮效果 */
.card-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 20px;
    margin-top: 2rem;
}

.card {
    background-color: rgba(255, 255, 255, 0.8);
    border-radius: 10px;
    padding: 20px;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
    transition: transform 0.3s ease;
}

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

.card img {
    width: 100%;
    border-radius: 10px;
    margin-bottom: 10px;
}

.card h3 {
    font-size: 1.5rem;
    margin-bottom: 10px;
}

.card p {
    font-size: 1rem;
    margin-bottom: 0;
}

/* 动态光效 */
.nav-item:hover,
.button {
    box-shadow: 0 0 10px #33ff99, 0 0 20px #33ff99, 0 0 30px #33ff99;
    transition: all 0.3s ease;
}

/* 表格样式 */
table {
    width: 100%;
    border-collapse: collapse;
    margin: 2rem 0;
}

th, td {
    border: 1px solid #ffffff;
    padding: 10px;
    text-align: left;
}

th {
    background-color: #33ff99;
    color: #000033;
}

td {
    background-color: rgba(255, 255, 255, 0.8);
}

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

    .hero-section p {
        font-size: 1.2rem;
    }

    .card-container {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 10px;
    }

    .card h3 {
        font-size: 1.2rem;
    }

    .card p {
        font-size: 0.9rem;
    }
}