body {
    background-image:  linear-gradient(white, black),url('coderonline-screenshot.jpg');
    background-blend-mode: saturation;
}

main {
    background-image: linear-gradient(to left, 
        rgba(255,255,255,0),
        rgba(255,255,255,1),
        rgba(255,255,255,1),
        rgba(255,255,255,1),
        rgba(255,255,255,1),
        rgba(255,255,255,0)
    ); 
}

.markdown h1 {
  color: #000;
}