body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
}

header {
    background-color: #ff0000; /* YouTube red */
    color: #ffffff;
    padding: 10px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

nav ul {
    list-style-type: none;
    margin: 0;
    padding: 0;
}

nav ul li {
    display: inline;
    margin-right: 20px;
}

nav ul li a {
    color: #ffffff;
    text-decoration: none;
}

main {
    padding: 20px;
}

.video {
    margin-bottom: 30px;
}

.video iframe {
    width: 100%; /* Make videos responsive */
    height: 175px; /* Adjust height for smaller videos */
}

.video-big iframe {
    height: 315px; /* Height for big video */
}

.video-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr); /* Four videos in one row */
    grid-gap: 20px;
}

.footer {
    background-color: #f9f9f9;
    padding: 10px;
    text-align: center;
}

/* Media query for smaller screens */
@media screen and (max-width: 768px) {
    .video-grid {
        grid-template-columns: repeat(2, 1fr); /* Two videos in one row */
    }
    
    .video iframe {
        height: 200px; /* Adjust height for smaller screens */
    }
    
    .video-big iframe {
        height: 300px; /* Height for big video on smaller screens */
    }
}