/* 全局样式 */
body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
    line-height: 1.6;
    color: #333;
}

.container {
    width: 80%;
    margin: 0 auto;
    padding: 20px;
}

h1, h2, h3 {
    margin-bottom: 15px;
    color: #0056b3; /* 主题色 */
}

a {
    text-decoration: none;
    color: #0056b3;
}

a:hover {
    color: #003366;
}

.button {
    display: inline-block;
    background-color: #0056b3;
    color: #fff;
    padding: 10px 20px;
    border-radius: 5px;
    transition: background-color 0.3s ease;
}

.button:hover {
    background-color: #003366;
}

/* 头部 */
header {
    background-color: #f4f4f4;
    padding: 10px 0;
    border-bottom: 1px solid #ddd;
}

header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

header .logo img {
    max-width: 150px; /* 调整logo大小 */
}

header nav ul {
    list-style: none;
    padding: 0;
    margin: 0;
    display: flex;
}

header nav ul li {
    margin-left: 20px;
}

header nav ul li:first-child {
    margin-left: 0;
}

/* Hero Section */
#hero {
    background-color: #e9ecef;
    text-align: center;
    padding: 50px 0;
}

#hero h1 {
    font-size: 2.5em;
}

/* About Section */
#about {
    padding: 50px 0;
}

/* Courses Section */
#courses {
    background-color: #f4f4f4;
    padding: 50px 0;
}

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

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

#courses .course-item img {
    max-width: 100%;
    height: auto;
    margin-bottom: 10px;
}

/* Footer */
footer {
    background-color: #333;
    color: #fff;
    text-align: center;
    padding: 20px 0;
}

footer a {
    color: #fff;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .container {
        width: 95%;
    }

    header .container {
        flex-direction: column;
        align-items: center;
    }

    header .logo {
        margin-bottom: 10px;
    }

    header nav ul {
        flex-direction: column;
        text-align: center;
    }

    header nav ul li {
        margin: 10px 0;
    }

    #hero h1 {
        font-size: 2em;
    }
}