/* 全局样式 */
body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    margin: 0;
    padding: 0;
    background-color: #f4f4f4;
    color: #333;
}

.container {
    width: 90%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 15px;
}

/* 导航栏样式 */
nav {
    background-color: #fff;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

nav h1 {
    margin: 0;
    font-size: 24px;
}

nav ul {
    list-style-type: none;
    margin: 0;
    padding: 0;
    display: flex;
    justify-content: space-around;
}

nav ul li {
    margin: 0 10px;
}

nav ul li a {
    text-decoration: none;
    color: #333;
    transition: color 0.3s ease;
}

nav ul li a:hover {
    color: #007BFF;
}

/* APP 介绍样式 */
.app-intro {
    text-align: center;
    padding: 50px 0;
}

.app-intro img {
    width: 150px;
    height: 150px;
    border-radius: 20px;
    margin-bottom: 20px;
}

.download-buttons {
    display: flex;
    justify-content: center;
    gap: 20px;
    margin-top: 20px;
}

.download-button {
    background-color: #007BFF;
    color: #fff;
    padding: 10px 20px;
    border-radius: 5px;
    text-decoration: none;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
}

.download-button:hover {
    background-color: #0056b3;
}

/* APP 特性样式 */
.app-features {
    padding: 50px 0;
    text-align: center;
}

.feature {
    margin-bottom: 30px;
}

.feature i {
    font-size: 36px;
    color: #007BFF;
    margin-bottom: 10px;
}

/* 用户评价样式 */
.testimonials {
    padding: 50px 0;
    text-align: center;
}

.testimonial {
    background-color: #fff;
    padding: 20px;
    border-radius: 5px;
    margin-bottom: 20px;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

/* 文章展示样式 */
.article-preview {
    padding: 50px 0;
}

.article-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 20px;
}

.article-card {
    background-color: #fff;
    padding: 20px;
    border-radius: 5px;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.article-card h3 {
    margin-top: 0;
}

.article-card a {
    color: #007BFF;
    text-decoration: none;
}

.article-card a:hover {
    text-decoration: underline;
}

/* 文章详情样式 */
.article-container {
    background-color: #fff;
    padding: 20px;
    border-radius: 5px;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
    margin-top: 50px;
}

.article-date {
    color: #999;
    margin-bottom: 20px;
}

.error {
    color: red;
    margin-top: 50px;
}

/* 页脚样式 */
footer {
    background-color: #fff;
    text-align: center;
    padding: 20px 0;
    box-shadow: 0 -2px 4px rgba(0, 0, 0, 0.1);
    margin-top: 50px;
}