body {
    margin: 0;
    font-family: Arial, sans-serif;
    background: url('../фон.jpg') no-repeat center center fixed;
    background-size: cover;
    color: white;
}

.background {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    filter: blur(8px);
    z-index: -1;
}

header, .content {
    text-align: center;
    margin: 20px;
}

.download-btn {
    display: inline-block;
    margin-top: 20px;
    padding: 10px 20px;
    background: #222;
    color: white;
    text-decoration: none;
    border-radius: 5px;
}

.download-btn:hover {
    background: #444;
}