Styling the Field Post Content

This CSS works:

/* GD Archive Item – hide Read More link and background */
.geodir-field-post_content .gd-read-more {
display: none !important;
}

/* GD Archive Item – change color */
.geodir-field-post_content {
color: green;
}

/* GD Archive Item – change font weight */
.geodir-field-post_content {
font-weight: bold;
}

/* GD Archive Item – change font style */
.geodir-field-post_content {
font-style: italic;
}

This CSS does NOT work:

/* GD Archive Item – change font size */
.geodir-field-post_content {
font-size: 18px;
}

/* GD Archive Item – change font size */
.geodir-field-post_content {
font-size: 0.875em;
}

/* GD Archive Item – change font size */
.geodir-field-post_content {
font-size: 150%;
}

/* GD Archive Item – hide View All link */
.geodir-field-post_content .gd-view-all {
display: none !important;
}

How can I change the font size in the Archive Item section?

Also, how can I get rid of the “View All” link that appears?