Responsive units not really working - wordpress

Question

I am working on a page that I'm trying to make responsive. I'm using background images and trying to lay them out one under the other but when adding the margin-top property using responsive units (vh, em, rem, %) my background image moves but there's a big variation on where the images should be on a laptop screen and an Ipad screen.
LINK:
http://dbtest.destinationballybunion.ie/?page_id=3733
As I've said I tried using all the responsive units and i keep getting the same variation in results. Is there a way this can be fixed without using media queries ?
PS I am using a drag and drop Wordpress plugin called Visual Composer
CSS FOR THE PAGE:
#container {
margin: 0%;
}
#container text area {
margin: 5%;
}
wrapper {
padding: 0px;
margin-top: 0px;
margin-bottom: 0px;
}
entry {
box-shadow: 0 0 0px rgba(0, 0, 0, 0);
padding: 0px;
}
entry-header.style {
position: absolute;
left: -9999px;
}
.entry-content a img, #attachment-nav a img {
background: none repeat scroll transparent;
border: 0px solid #EEEEEE;
box-shadow: 0 0 0px #EEEEEE;
max-width: 98.5%;
padding: 0%;
}
.entry-content a:hover img, #attachment-nav a:hover img {
background: transparent repeat scroll 0 0;
}
.entry-title {
display:none;
}
.single .entry, .page .entry, .error404 .entry {
margin-bottom: 5.1% !important;
padding: 0;
}
#site-title {
height:100%;
width:100%;
}
#site-title, #site-description {
line-height: 100%;
}
#site-title {
margin: 0 0;
}
#site-title img {
margin: 0;
}
#site-title img {
padding: 0;
}
#access {
position: relative;
margin-top:-0.5%;
}
.tearhist {
background-size: 100% 100%;
background-size: contain;
background-repeat:no-repeat;
}
.tearhist {
position: absolute;
margin-top: -11.000em;
z-index: 100;
}
.tearytext {
position: absolute;
margin-top: 2.500em;
margin-right: 2.500em;
}
.tearytext h4 {
font-size: 24px;
font-size: 1.100em;
line-height: 100%;
}
.histmainb {
background-size: 100% auto;
background-repeat:no-repeat;
}
.histmainb {
position: relative;
}
.histblocka {
background-image: url('http://dbtest.destinationballybunion.ie/wp-content/uploads
/2014/10/HISTOBACK-1-SMALL.png');
background-size: auto auto;
background-size: contain;
background-repeat:no-repeat;
}
.histblocka {
position: absolute;
}
.histblocka p {
margin-right: 23.000em;
margin-left: 3.500em;
}
.histblocka h2 {
margin-top: 3.500em;
margin-left: 3.000em;
}
.histblocka h2 {
text-shadow: 0px 2px 3px #666;
}
.histblocka p {
font-size: 1.000em;
}
.histblocka h2 {
font-size: 1.000em;
}
.nublockb {
position: absolute;
margin-top: 21.000em;
}
.nublockb {
background-image: url('http://dbtest.destinationballybunion.ie/wp-content/uploads
/2014/10/HISTOBACK-3-SMALL.png');
background-size: auto auto;
background-size: contain;
background-repeat:no-repeat;
}