CSS - display: none; not working

Another trick is to use

.class {
position: absolute;
visibility:hidden;
display:none;
}

This is not likely to mess up your flow (because it takes it out of flow) and makes sure that the user can't see it, and then if display:none works later on it will be working. Keep in mind that visibility:hidden may not remove it from screen readers.

Try add this to your css

#tfl {
display: none !important;
}

This is because the inline style display:block is overriding your CSS. You'll need to either remove this inline style or use:

#tfl {
  display: none !important;
}

This overrides inline styles. Note that using !important is generally not recommended unless it's a last resort.

Remove display: block; in the div #tfl style property

<div id="tfl" style="display: block; width: 187px; height: 260px;

Inline styles take priority over an external CSS file.