/* 主体结构与布局设置 */
/* 使用 Flexbox 和 Grid 布局实现响应式设计 */
body {
    margin: 0;
    padding: 0;
    font-family: 'Roboto', sans-serif;
    background: linear-gradient(135deg, #2c3e50, #34495e);
    color: #ecf0f1;
}

/* 导航栏样式 */
.navbar {
    position: fixed;
    top: 0;
    width: 100%;
    background-color: rgba(44, 62, 80, 0.9);
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 2rem;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
    z-index: 1000;
    transition: background-color 0.3s ease;
}

.navbar a {
    color: #ecf0f1;
    text-decoration: none;
    margin: 0 1rem;
    transition: color 0.3s;
}

.navbar a:hover {
    color: #e67e22;
}

/* 章节导航系统样式 */
.chapter-nav {
    position: fixed;
    top: 80px;
    right: 20px;
    background-color: rgba(44, 62, 80, 0.8);
    padding: 1rem;
    border-radius: 8px;
}

.chapter-nav a {
    display: block;
    color: #ecf0f1;
    text-decoration: none;
    margin: 0.5rem 0;
    transition: color 0.3s;
}

.chapter-nav a:hover {
    color: #e67e22;
}

/* 英雄横幅样式 */
.hero {
    height: 80vh;
    background-image: url('https://images.gptkong.com/demo/sample1.png');
    background-size: cover;
    background-position: center;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
}

.hero::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(44, 62, 80, 0.5);
}

.hero-content {
    position: relative;
    text-align: center;
    color: #ecf0f1;
}

.hero-title {
    font-size: 3rem;
    animation: fadeInDown 2s ease-out;
}

.hero-subtitle {
    font-size: 1.5rem;
    margin-top: 1rem;
    animation: fadeInUp 2s ease-out;
    animation-delay: 1s;
}

@keyframes fadeInDown {
    from {
        opacity: 0;
        transform: translateY(-50px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(50px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* 功能展示区样式 */
.features {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    padding: 4rem 2rem;
    background: linear-gradient(135deg, #34495e, #2c3e50);
}

.feature-item {
    background-color: rgba(236, 240, 241, 0.1);
    border-radius: 10px;
    padding: 2rem;
    text-align: center;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s, box-shadow 0.3s;
}

.feature-item:hover {
    transform: translateY(-10px);
    box-shadow: 0 10px 15px rgba(0, 0, 0, 0.2);
}

.feature-icon {
    font-size: 3rem;
    color: #e67e22;
    margin-bottom: 1rem;
}

.feature-title {
    font-size: 1.5rem;
    margin-bottom: 1rem;
}

.feature-description {
    font-size: 1rem;
    line-height: 1.5;
}

/* 客户案例展示区样式 */
.cases {
    padding: 4rem 2rem;
    background: linear-gradient(135deg, #2c3e50, #34495e);
    color: #ecf0f1;
}

.cases-title {
    text-align: center;
    font-size: 2rem;
    margin-bottom: 2rem;
}

.case-carousel {
    display: flex;
    overflow-x: auto;
    gap: 2rem;
}

.case-item {
    flex: 0 0 300px;
    background-color: rgba(236, 240, 241, 0.1);
    border-radius: 10px;
    padding: 1rem;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

.case-item img {
    width: 100%;
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.case-description {
    margin-top: 1rem;
    font-size: 1rem;
    line-height: 1.5;
}

/* 互动演示区样式 */
.demo {
    padding: 4rem 2rem;
    background: linear-gradient(135deg, #34495e, #2c3e50);
    text-align: center;
}

.demo-title {
    font-size: 2rem;
    margin-bottom: 2rem;
}

.demo-content {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 2rem;
}

.demo-content img {
    width: 300px;
    height: 300px;
    border-radius: 10px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s;
}

.demo-content img:hover {
    transform: scale(1.05);
}

/* 联系表单区样式 */
.contact {
    padding: 4rem 2rem;
    background: linear-gradient(135deg, #2c3e50, #34495e);
    text-align: center;
}

.contact-title {
    font-size: 2rem;
    margin-bottom: 2rem;
}

.contact-form {
    max-width: 600px;
    margin: 0 auto;
    background-color: rgba(236, 240, 241, 0.1);
    padding: 2rem;
    border-radius: 10px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

.contact-form input,
.contact-form textarea {
    width: 100%;
    padding: 0.75rem;
    margin-bottom: 1rem;
    border: none;
    border-radius: 5px;
    outline: none;
}

.contact-form input:focus,
.contact-form textarea:focus {
    box-shadow: 0 0 5px #e67e22;
}

.contact-form button {
    background-color: #e67e22;
    color: #ecf0f1;
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    transition: background-color 0.3s, transform 0.3s;
}

.contact-form button:hover {
    background-color: #d35400;
    transform: scale(1.05);
}

/* 图片装饰样式 */
.decorative-images {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
    justify-content: center;
    padding: 2rem;
}

.decorative-images img {
    width: 150px;
    height: 150px;
    border-radius: 10px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s, box-shadow 0.3s;
}

.decorative-images img:hover {
    transform: scale(1.05);
    box-shadow: 0 10px 15px rgba(0, 0, 0, 0.2);
}

/* 折叠区域样式 */
.collapsible {
    background-color: rgba(236, 240, 241, 0.1);
    color: #ecf0f1;
    cursor: pointer;
    padding: 1rem;
    width: 100%;
    border: none;
    text-align: left;
    outline: none;
    font-size: 1.25rem;
    transition: background-color 0.3s;
    border-radius: 5px;
    margin-bottom: 1rem;
}

.collapsible:hover {
    background-color: rgba(230, 126, 34, 0.7);
}

.content {
    padding: 0 1rem;
    display: none;
    overflow: hidden;
    background-color: rgba(236, 240, 241, 0.05);
    border-radius: 5px;
    margin-bottom: 1rem;
}

.active + .content {
    display: block;
}

/* 响应式设计调整 */
@media (max-width: 1200px) {
    .hero-title {
        font-size: 2.5rem;
    }

    .feature-title {
        font-size: 1.25rem;
    }
}

@media (max-width: 768px) {
    .navbar {
        flex-direction: column;
        align-items: center;
    }

    .chapter-nav {
        top: 120px;
    }

    .features {
        grid-template-columns: 1fr;
    }

    .demo-content {
        flex-direction: column;
    }
}

/* CSS3 代码示例区块样式 */
.code-block {
    background-color: rgba(44, 62, 80, 0.9);
    padding: 1rem;
    border-radius: 5px;
    overflow-x: auto;
    margin: 2rem 0;
}

.code-block code {
    color: #e67e22;
    font-family: 'Courier New', Courier, monospace;
    font-size: 0.9rem;
}

/* 提示信息样式 */
.notice {
    text-align: center;
    font-size: 1.25rem;
    margin: 2rem 0;
    padding: 1rem;
    background-color: rgba(236, 240, 241, 0.1);
    border-radius: 10px;
}