Try this code instead of the first one:
.mod_events_monthyear, .mod_events_table {
float: left;
width: 170px;
margin-right: 20px !important;
}
.mod_events_table {
margin-top: 30px !important;
margin-left: -190px !important;
}
Anyway, this is dirty tricks in CSS and I do recommend you create a template override for that with proper HTML strucutre

.
Best!!