* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Arial', sans-serif; 
    color: #333;
    background-color: #f4f4f9;
}

.container {
    width: 90%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px 0;
}


.header {
    background-color: #fff;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
    position: sticky; 
    top: 0;
    z-index: 1000;
}

.header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 10px 0;
}

.logo img {
    height: 40px;
}

.main-nav ul {
    list-style: none;
    display: flex;
}

.main-nav ul li a {
    display: block;
    padding: 10px 15px;
    text-decoration: none;
    color: #333;
    transition: color 0.3s;
}

.main-nav ul li a:hover {
    color: #007bff; 
}

.dropdown {
    position: relative;
}

.dropdown-content {
    display: none;
    position: absolute;
    background-color: #fff;
    min-width: 200px;
    box-shadow: 0px 8px 16px 0px rgba(0,0,0,0.2);
    z-index: 1;
    list-style: none;
    padding: 10px 0;
}

.dropdown-content a {
    padding: 12px 16px;
    text-decoration: none;
    display: block;
}

.dropdown:hover .dropdown-content {
    display: block; 
}


.section {
    padding: 60px 0;
    text-align: center;
}

.section h2 {
    margin-bottom: 30px;
    color: #007bff;
}

.dark-bg {
    background-color: #e9ecef;
}


.product-item {
    margin-bottom: 40px;
}

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

.image-box {
    flex: 1;
    max-width: 45%;
    border: 1px solid #ccc;
    padding: 10px;
    background-color: #fff;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.05);
}

.image-box img {
    width: 100%;
    height: auto;
    display: block;
    margin-bottom: 10px;
}


.button {
    display: inline-block;
    padding: 10px 20px;
    margin: 10px;
    background-color: #007bff;
    color: white;
    text-decoration: none;
    border-radius: 5px;
    transition: background-color 0.3s;
}

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

.secondary {
    background-color: #6c757d;
}

.secondary:hover {
    background-color: #5a6268;
}


.developer-info {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
}

.author-photo {
    width: 150px;
    height: 150px;
    border-radius: 50%;
    object-fit: cover;
    margin-bottom: 20px;
    border: 3px solid #007bff;
}


.footer {
    background-color: #333;
    color: white;
    padding: 15px 0;
    text-align: center;
    font-size: 0.9em;
}


@media (max-width: 768px) {
    .header .container {
        flex-direction: column;
        text-align: center;
    }

    .main-nav ul {
        flex-direction: column;
        width: 100%;
        margin-top: 10px;
    }

    .main-nav ul li {
        width: 100%;
        text-align: center;
    }
    
    .dropdown:hover .dropdown-content {
        position: static; 
        width: 100%;
    }

    .image-comparison {
        flex-direction: column;
    }

    .image-box {
        max-width: 100%;
    }
    
    .social-links {
        margin-top: 10px;
    }
}