/* 全局样式设置 */
body {
    margin: 0;
    padding: 0;
    font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif;
    background: linear-gradient(135deg, #1E3A8A, #F3F4F6, #E5E7EB);
    color: #ffffff;
    transition: background 0.5s ease;
}

/* 导航栏样式 */
.navbar {
    position: fixed;
    top: 0;
    width: 100%;
    background-color: rgba(30, 58, 138, 0.9);
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px 30px;
    z-index: 1000;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.navbar a {
    color: #ffffff;
    text-decoration: none;
    margin: 0 15px;
    font-size: 16px;
    transition: color 0.3s ease;
}

.navbar a:hover {
    color: #F97316;
}

/* 顶部横幅样式 */
.header {
    height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    background: url('https://images.gptkong.com/demo/sample1.png') no-repeat center center/cover;
}

.header h1 {
    font-size: 48px;
    margin-bottom: 20px;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.5);
}

.header p {
    font-size: 20px;
    max-width: 600px;
    margin: 0 auto 40px;
    line-height: 1.5;
}

.header .button {
    background-color: #F97316;
    border: none;
    padding: 15px 30px;
    color: #fff;
    border-radius: 4px;
    cursor: pointer;
    transition: background-color 0.3s ease, box-shadow 0.3s ease;
}

.header .button:hover {
    background-color: #ea580c;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
}

/* 模块样式 */
.section {
    padding: 80px 30px;
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    justify-content: center;
}

.section:nth-child(even) {
    background: rgba(255, 255, 255, 0.1);
}

.section:nth-child(odd) {
    background: rgba(0, 0, 0, 0.1);
}

.section img {
    width: 320px;
    height: 320px;
    border-radius: 16px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.3);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    margin: 20px;
}

.section img:hover {
    transform: scale(1.05);
    box-shadow: 0 8px 20px rgba(0,0,0,0.4);
}

.section-content {
    max-width: 600px;
    margin: 20px;
}

.section-content h2, .section-content h3, .section-content h4 {
    color: #F97316;
    margin-bottom: 15px;
}

.section-content p {
    font-size: 16px;
    line-height: 1.6;
    margin-bottom: 20px;
}

.section-content pre {
    background: rgba(255, 255, 255, 0.2);
    padding: 15px;
    border-radius: 8px;
    overflow-x: auto;
    margin-bottom: 20px;
}

.section-content code {
    color: #10B981;
    font-family: 'Courier New', Courier, monospace;
}

/* 底部导航栏 */
.footer-nav {
    position: fixed;
    bottom: 0;
    left: 0;
    width: 100%;
    background-color: rgba(30, 58, 138, 0.9);
    display: flex;
    justify-content: space-around;
    padding: 10px 0;
}

.footer-nav a {
    color: #ffffff;
    text-decoration: none;
    font-size: 16px;
    transition: color 0.3s ease;
}

.footer-nav a:hover {
    color: #F97316;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .navbar {
        flex-direction: column;
    }

    .navbar a {
        margin: 10px 0;
    }

    .header h1 {
        font-size: 32px;
    }

    .header p {
        font-size: 16px;
        padding: 0 20px;
    }

    .section {
        flex-direction: column;
    }

    .section img {
        width: 80%;
        height: auto;
    }

    .section-content {
        max-width: 90%;
    }
}

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

.fade-in {
    animation: fadeIn 1s ease-out forwards;
}