You use
#main_text .title {
/* Properties */
}
If you just put a space between the selectors, styles will apply to all children (and children of children) of the first. So in this case, any child element of #main_text
with the class name title
. If you use >
instead of a space, it will only select the direct child of the element, and not children of children, e.g.:
#main_text > .title {
/* Properties */
}
Either will work in this case, but the first is more typically used.