First, you need to load your CSS AFTER the default Feeds API CSS is loaded, which means you have to load it at the tail end of the document head. This ensures that it takes precedence over the default stylesheet.
And second, you have to add !important to your display: none; rules. Here is what I ended up with which seemed to produce what you are looking for:
/* google.feeds.FeedControl classes
* customization overrides
*/
/* the main feed display */
.gfc-results {
font-family: Verdana, Geneva, sans-serif;
font-size: 12px;
}
.gfc-result {
line-height: 16px;
padding-bottom: 12px;
}
/* Feed Item title/headline */
.gf-result .gf-title {
font-weight: bold;
font-size: 14px;
overflow: visible;
}
.gfc-resultsHeader, .gf-result .gf-author, .gf-result .gf-spacer, .gf-result .gf-relativePublishedDate, .gf-result .gf-spacer {
display: none !important;
}
jg
Jeremy R. Geerdes