/* 全局样式 */
body {
    margin: 0;
    font-family: 'Helvetica', 'Arial', sans-serif;
    line-height: 1.6;
    color: #fff;
    background: linear-gradient(135deg, #003366, #336699, #003366);
    background-size: 200% 200%;
    animation: gradientShift 10s infinite alternate;
}
@keyframes gradientShift {
    0% { background-position: 0% 50%; }
    100% { background-position: 100% 50%; }
}
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
    display: grid;
    grid-template-columns: repeat(12, 1fr);
    gap: 20px;
}
h1, h2, h3, h4, h5, h6 {
    color: #FFA500;
    font-weight: bold;
}
p, li, table {
    font-size: 1rem;
    line-height: 1.8;
    color: #f0f8ff;
}
a {
    color: #FFD700;
    text-decoration: none;
    transition: color 0.3s ease;
}
a:hover {
    color: #FFA500;
}
code, pre {
    background: rgba(255, 255, 255, 0.1);
    padding: 10px;
    border-radius: 5px;
    font-family: 'Courier New', monospace;
    color: #FFA500;
    font-size: 0.9rem;
}
pre {
    overflow-x: auto;
}
button {
    background: #FFA500;
    color: #003366;
    border: none;
    padding: 10px 20px;
    border-radius: 5px;
    cursor: pointer;
    transition: transform 0.3s ease, background-color 0.3s ease;
}
button:hover {
    transform: scale(1.1);
    background-color: #FFD700;
}
.grid-item {
    background: rgba(0, 51, 102, 0.8);
    padding: 20px;
    border-radius: 10px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.2);
}
.hero {
    grid-column: span 12;
    text-align: center;
    padding: 50px 20px;
    background: url('https://images.gptkong.com/demo/sample1.png') no-repeat center/cover, linear-gradient(to bottom, #003366, #336699);
    color: #fff;
}
.hero h1 {
    font-size: 3rem;
    margin-bottom: 20px;
}
.features {
    grid-column: span 12;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 20px;
}
.feature-item {
    text-align: center;
    padding: 20px;
    background: rgba(51, 102, 153, 0.8);
    border-radius: 10px;
    transition: transform 0.3s ease;
}
.feature-item:hover {
    transform: translateY(-10px);
}
.cta {
    grid-column: span 12;
    text-align: center;
    padding: 50px 20px;
    background: linear-gradient(to right, #FFA500, #FFD700);
    color: #003366;
    border-radius: 10px;
}
@media (max-width: 768px) {
    .hero h1 {
        font-size: 2rem;
    }
    .features {
        grid-template-columns: 1fr;
    }
}