/* Override background of code blocks (especially shell/console) */
.highlight .hll {
    background-color: transparent !important;
}

/* General code block override */
div.highlight pre {
    background-color: #f8f8f8 !important;  /* light gray or whatever you like */
    color: #2c3e50;
    border: 1px solid #ddd;
    border-radius: 5px;
    padding: 1em;
    font-family: Consolas, Monaco, monospace;
}