/* 全局样式重置，确保一致性 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
/* 设置页面字体和背景渐变 */
body {
    font-family: 'Roboto', sans-serif;
    color: #ffffff;
    background: linear-gradient(135deg, #1B385E, #243B55, #2C5364);
    line-height: 1.6;
    font-size: 16px;
    overflow-x: hidden;
    scroll-behavior: smooth;
}
/* 导航栏样式 */
nav {
    position: fixed;
    top: 0;
    width: 100%;
    background: rgba(27, 56, 94, 0.9);
    padding: 20px 40px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    z-index: 1000;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}
nav .logo {
    font-size: 24px;
    font-weight: bold;
}
nav ul {
    list-style: none;
    display: flex;
}
nav ul li {
    margin-left: 30px;
}
nav ul li a {
    color: #ffffff;
    text-decoration: none;
    font-size: 16px;
    transition: color 0.3s;
}
nav ul li a:hover {
    color: #27AE60;
}
/* 汉堡菜单样式 */
.hamburger {
    display: none;
    flex-direction: column;
    cursor: pointer;
}
.hamburger div {
    width: 25px;
    height: 3px;
    background: #ffffff;
    margin: 4px 0;
    transition: all 0.3s;
}
/* 移动端导航 */
@media (max-width: 768px) {
    nav ul {
        display: none;
        flex-direction: column;
        background: rgba(27, 56, 94, 0.95);
        position: absolute;
        top: 70px;
        right: 40px;
        width: 200px;
        border-radius: 8px;
        box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    }
    nav ul.active {
        display: flex;
    }
    nav ul li {
        margin: 15px 0;
    }
    .hamburger {
        display: flex;
    }
}
/* 主视觉区域样式 */
.header {
    height: 100vh;
    background: url('https://images.gptkong.com/demo/sample1.png') no-repeat center center/cover;
    display: flex;
    justify-content: center;
    align-items: center;
    position: relative;
    text-align: center;
}
.header::after {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(27, 56, 94, 0.6);
}
.header-content {
    position: relative;
    z-index: 1;
}
.header-content h1 {
    font-size: 48px;
    margin-bottom: 20px;
    color: #ffffff;
    animation: fadeInDown 2s ease-out;
}
.header-content p {
    font-size: 20px;
    color: #ffffff;
    animation: fadeInUp 2s ease-out;
}
/* 动画效果 */
@keyframes fadeInDown {
    from { opacity: 0; transform: translateY(-20px); }
    to { opacity: 1; transform: translateY(0); }
}
@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}
/* 主要内容区域 */
.section {
    padding: 80px 40px;
    background: #ffffff;
    color: #1B385E;
}
.section:nth-child(even) {
    background: #f0f0f0;
}
.section h2 {
    font-size: 32px;
    margin-bottom: 20px;
    color: #1B385E;
}
.section p {
    font-size: 16px;
    margin-bottom: 20px;
}
.section img {
    width: 100%;
    max-width: 320px;
    border-radius: 10px;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
    transition: transform 0.3s, box-shadow 0.3s;
}
.section img:hover {
    transform: scale(1.05);
    box-shadow: 0 8px 16px rgba(0, 0, 0, 0.3);
}
/* 按钮样式 */
.btn {
    background-color: #27AE60;
    color: #ffffff;
    padding: 12px 24px;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    transition: background-color 0.3s, transform 0.2s;
    text-decoration: none;
    font-size: 16px;
}
.btn:hover {
    background-color: #1E8449;
}
.btn:active {
    transform: scale(0.95);
}
/* 卡片式布局 */
.card-container {
    display: flex;
    flex-wrap: wrap;
    gap: 20px;
    justify-content: center;
}
.card {
    background: #ffffff;
    border-radius: 8px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    width: 300px;
    padding: 20px;
    transition: transform 0.3s, box-shadow 0.3s;
}
.card:hover {
    transform: translateY(-10px);
    box-shadow: 0 8px 12px rgba(0, 0, 0, 0.2);
}
/* 代码块样式 */
code {
    background: #f5f5f5;
    padding: 5px 10px;
    border-radius: 4px;
    font-family: 'Courier New', Courier, monospace;
}
pre {
    background: #f5f5f5;
    padding: 15px;
    border-radius: 8px;
    overflow-x: auto;
}
/* 折叠区域样式 */
.collapsible {
    background-color: #27AE60;
    color: white;
    cursor: pointer;
    padding: 10px;
    width: 100%;
    border: none;
    text-align: left;
    outline: none;
    font-size: 18px;
    border-radius: 4px;
    margin-bottom: 10px;
}
.active, .collapsible:hover {
    background-color: #1E8449;
}
.content {
    padding: 0 18px;
    display: none;
    overflow: hidden;
    background-color: #f1f1f1;
    color: #1B385E;
    border-radius: 4px;
    margin-bottom: 10px;
}
/* 章节导航 */
.chapter-nav {
    position: fixed;
    top: 100px;
    right: 40px;
    background: rgba(27, 56, 94, 0.8);
    padding: 20px;
    border-radius: 8px;
    z-index: 500;
}
.chapter-nav ul {
    list-style: none;
}
.chapter-nav ul li {
    margin-bottom: 10px;
}
.chapter-nav ul li a {
    color: #ffffff;
    text-decoration: none;
    font-size: 14px;
    transition: color 0.3s;
}
.chapter-nav ul li a:hover {
    color: #27AE60;
}
/* 响应式调整 */
@media (max-width: 768px) {
    .chapter-nav {
        display: none;
    }
}