/* 全站统一使用HTML5与CSS3技术，确保现代浏览器的兼容性和响应式设计 */
body {
    margin: 0;
    padding: 0;
    font-family: 'PingFang SC', 'Helvetica Neue', Helvetica, Arial, sans-serif; /* 使用无衬线字体，增强现代感 */
    background: linear-gradient(135deg, #1E3A8A 70%, #F97316 25%, #FFFFFF 5%); /* 渐变背景，符合主色调与配色比例 */
    color: #1E3A8A; /* 主色调文字颜色，保证良好的可读性 */
    line-height: 1.6;
}

/* 固定导航栏样式 */
.navbar {
    position: fixed;
    top: 0;
    width: 100%;
    background-color: rgba(30, 58, 138, 0.9);
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    z-index: 1000;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 10px 50px;
    transition: background-color 0.3s ease;
}

.navbar a {
    color: #FFFFFF;
    text-decoration: none;
    margin: 0 15px;
    position: relative;
    transition: color 0.3s ease;
}

.navbar a::after {
    content: '';
    position: absolute;
    width: 0;
    height: 2px;
    background-color: #F97316;
    left: 50%;
    bottom: -5px;
    transition: width 0.3s ease, left 0.3s ease;
}

.navbar a:hover::after {
    width: 100%;
    left: 0;
}

.header {
    height: 100vh;
    background: url('https://images.gptkong.com/demo/sample1.png') center center/cover no-repeat;
    display: flex;
    justify-content: center;
    align-items: center;
    position: relative;
    text-align: center;
    color: #FFFFFF;
}

.header::after {
    content: "这是一个网页样式设计参考";
    position: absolute;
    bottom: 20px;
    left: 50%;
    transform: translateX(-50%);
    background: rgba(30, 58, 138, 0.8);
    padding: 10px 20px;
    border-radius: 5px;
    font-size: 1.2em;
}

.carousel {
    position: relative;
    width: 100%;
    height: 100vh;
    overflow: hidden;
}

.carousel-slide {
    position: absolute;
    width: 100%;
    height: 100%;
    background-size: cover;
    background-position: center;
    animation: slideAnimation 20s infinite;
}

@keyframes slideAnimation {
    0% { opacity: 0; transform: scale(1.1); }
    10% { opacity: 1; transform: scale(1); }
    25% { opacity: 1; }
    35% { opacity: 0; transform: scale(0.9); }
    100% { opacity: 0; }
}

.service-section {
    padding: 80px 50px;
    background-color: #FFFFFF;
    display: flex;
    flex-wrap: wrap;
    justify-content: space-around;
}

.service-item {
    flex: 0 0 30%;
    text-align: center;
    margin: 20px 0;
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.service-item.visible {
    opacity: 1;
    transform: translateY(0);
}

.service-item img {
    width: 80px;
    height: 80px;
    margin-bottom: 20px;
    border-radius: 10px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

.service-item h3 {
    color: #1E3A8A;
    margin-bottom: 10px;
    font-size: 1.5em;
}

.service-item p {
    color: #555555;
    font-size: 1em;
}

.article-section {
    padding: 80px 50px;
    max-width: 1200px;
    margin: 0 auto;
}

.article-section h2 {
    font-size: 2em;
    margin-bottom: 20px;
    color: #1E3A8A;
}

.article-section p {
    font-size: 1.1em;
    margin-bottom: 20px;
    color: #333333;
}

.article-section pre {
    background: #F3F4F6;
    padding: 15px;
    border-radius: 5px;
    overflow-x: auto;
    margin-bottom: 20px;
}

.article-section code {
    font-family: 'Courier New', Courier, monospace;
    color: #F97316;
}

.footer {
    background-color: #1E3A8A;
    color: #FFFFFF;
    padding: 40px 50px;
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
}

.footer div {
    margin: 10px 0;
}

.footer a {
    color: #F97316;
    text-decoration: none;
    margin-right: 15px;
    transition: color 0.3s ease;
}

.footer a:hover {
    color: #FFFFFF;
}

.language-selector select {
    background-color: #FFFFFF;
    color: #1E3A8A;
    border: none;
    padding: 5px;
    border-radius: 3px;
}

.responsive-image {
    width: 100%;
    height: auto;
    display: block;
    border-radius: 10px;
    box-shadow: 0 4px 8px rgba(0,0,0,0.1);
    transition: transform 0.3s ease;
}

.responsive-image:hover {
    transform: scale(1.05);
}

@media (max-width: 768px) {
    .navbar {
        padding: 10px 20px;
    }
    .service-item {
        flex: 0 0 100%;
        padding: 0 10px;
    }
    .article-section {
        padding: 40px 20px;
    }
    .footer {
        grid-template-columns: 1fr;
        text-align: center;
    }
}