split div into 2 columns doesn't work - html

Question

Can you please help me, it took me so much time trying to fixe this problem.
i have 2 slider and i need to split each slide into 2 colums. The problem is that the second column which is float: right doesn't show in both sliders .
Here is a code pen that shows the problem codepen
thank you
Here is my structure:
.Dash_map_wrapSlider {
position: absolute;
overflow: hidden;
height: 100%;
width: calc(100% - 3rem);
bottom: calc(-80% + 10rem);
left: 3rem;
background: #fff;
border: 1px solid;
transition: 0.5s;
z-index: 1;}
.Dash_map_wrapSlider:hover{
bottom: 0rem;
transition: 0.5s;}
.Dash_map_wrapSlider:hover{
bottom: 0rem;
transition: 0.5s;}
.Dash_map_wrapSliderchoise {
background: #3E474F;
box-shadow: 0 .5em 1em #111;
position: absolute;
left: 0;
bottom: 0;
z-index: 900;
width: 100%;
height: 2rem;
line-height: 2rem;
text-align: center;
vertical-align: middle;}
.Dash_map_sumSlide {
height: 100%;
width: 100%;
position: absolute;
top: 0;
left: 100%;
z-index: 10;
background-color: #fff;
transition: left 0s .75s;}
.clsDashMap_sumSlideInput {
display: none;
height: 11rem;}
.clsDashMap_sumSlideTitle {
position : absolute;
top:0;
width: 100%;
height: 2rem;
left: inherit;
color: #fff;
background-color: #73b9ff;
text-align: center;
font-weight: bold;
font-size: 1.20rem;}
.clsDashMap_sumSlideContentBoxTitle {
font-weight: bold;
color: #666;}
.clsDashMap_sumSlideSiteContentSummary {
position : absolute;
top: 2rem;
width: 100%;
height: 16rem;
color: #000000;
background-color: aliceblue;
text-align: center;}
.clsDashMap_sumSlideContent {
position: absolute;
top: 20rem;
margin: auto;
width: 100%;
color: #000000;}
[id^="Dash"]:checked + .Dash_map_sumSlide {
left: 0;
z-index: 100;
transition: left .65s ease-out;}
.Dash_map_wrapSliderchoise label {
color: #fff;
cursor: pointer;
display: inline-block;
line-height: 2rem;
font-size: 0.75rem;
font-weight: bold;
padding: 0 1em;}
.clsDashMap_sumSlideContentBox {
margin: auto;
float: left;
padding: 10px;
text-align: center;}
<div class="Dash_map_wrapSlider">
<div style="border: 1px solid red;width: 100%;">
<input id="Dash_map_sumSlideSite" class="clsDashMap_sumSlideInput" type="radio" name="slides" checked>
<div class="Dash_map_sumSlide slide_Site " style="float: left;width: 50%;border: 2px solid yellow;">
<div class="clsDashMap_sumSlideTitle">SITE</div>
<div class="clsDashMap_sumSlideSiteContentSummary">
<div class="clsDashMap_sumSlideContentBox">
<div class="clsDashMap_sumSlideContentBoxTitle">Etat</div>
<div class="green led">OK</div>
<div class="red led">KO</div>
</div>
<div class="clsDashMap_sumSlideContentBox">
<div class="clsDashMap_sumSlideContentBoxTitle">AlarmesSite</div>
<canvas id="pieChartAlm" ></canvas>
</div>
<div class="clsDashMap_sumSlideContentBox">
<div class="clsDashMap_sumSlideContentBoxTitle">TicketsSite</div>
<canvas id="pieChartTkt" ></canvas>
</div>
</div>
<div class="clsDashMap_sumSlideContent">put here content</div>
</div>
<div class="Dash_map_sumSlide slide_Alarme" style="float: right;width: 50%; border: 2px solid green;">
<div class="clsDashMap_sumSlideTitle" >ALARME</div>
<div class="clsDashMap_sumSlideSiteContentSummary">
<div class="clsDashMap_sumSlideContentBox">
<div class="clsDashMap_sumSlideContentBoxTitle">Etat</div>
<div class="green led">OK</div>
<div class="red led">KO</div>
</div>
<div class="clsDashMap_sumSlideContentBox">
<div class="clsDashMap_sumSlideContentBoxTitle">ALARME1Alm</div>
<canvas id="pieChartAlm" ></canvas>
</div>
<div class="clsDashMap_sumSlideContentBox">
<div class="clsDashMap_sumSlideContentBoxTitle">Tickets1Alm</div>
<canvas id="pieChartTkt" ></canvas>
</div>
</div>
<div class="clsDashMap_sumSlideContent">put here content</div>
</div>
</div>
<div style="border: 1px solid red;">
<input id="Dash_map_sumSlideAlarme" class="clsDashMap_sumSlideInput" type="radio" name="slides" checked>
<div class="Dash_map_sumSlide slide_Site " style="width: 50%;border: 2px solid black;">
<div class="clsDashMap_sumSlideTitle">TECHNICIEN</div>
<div class="clsDashMap_sumSlideSiteContentSummary">
<div class="clsDashMap_sumSlideContentBox">
<div class="clsDashMap_sumSlideContentBoxTitle">Etat</div>
<div class="green led">OK</div>
<div class="red led">KO</div>
</div>
<div class="clsDashMap_sumSlideContentBox">
<div class="clsDashMap_sumSlideContentBoxTitle">Alarmes2Tech</div>
</div>
<div class="clsDashMap_sumSlideContentBox">
<div class="clsDashMap_sumSlideContentBoxTitle">Tickets2Tech</div>
</div>
</div>
<div class="clsDashMap_sumSlideContent">put here content</div>
</div>
<div class="Dash_map_sumSlide slide_Alarme" style="width: 50%; float: right;border: 2px solid darkturquoise;">
<div class="clsDashMap_sumSlideTitle" style="position: initial;">ACTION</div>
<div class="clsDashMap_sumSlideSiteContentSummary">
<div class="clsDashMap_sumSlideContentBox">
<div class="clsDashMap_sumSlideContentBoxTitle">Etat</div>
<div class="green led">OK</div>
<div class="red led">KO</div>
</div>
<div class="clsDashMap_sumSlideContentBox">
<div class="clsDashMap_sumSlideContentBoxTitle">alarme3Act</div>
</div>
<div class="clsDashMap_sumSlideContentBox">
<div class="clsDashMap_sumSlideContentBoxTitle">Tickets3Act</div>
</div>
</div>
<div class="clsDashMap_sumSlideContent">put here content</div>
</div>
</div>

Answer 1

Instead of float: right; give left: 50%; to the second column

Answer 2

Have you tried out Bootstrap Grid? I think it is just what you need.