Align all 4 items in HTML/CSS - html

Question

I have my timer that has date/hour/minute/seconds and the only one that doesn't align is the seconds. I tried many things such as different ways to align. So how can I align all the timer's items.
Can someone help me?
HTML
<div class="jumbotron timer">
<h2>Time until the tracker is activated</h2>
<div class="timertxtc">
<div class="timertxt" id="daysBox"></div>
<h4>Days</h4>
</div>
<h3 class="space">1</h3>
<div class="timertxtc">
<div class="timertxt" id="hoursBox"></div>
<h4>Hours</h4>
</div>
<h3 class="space">1</h3>
<div class="timertxtc">
<div class="timertxt" id="minsBox"></div>
<h4>Minutes</h4>
</div>
<h3 class="space">1</h3>
<div class="timertxtc">
<div class="timertxt" id="secsBox"></div>
<h4>Seconds</h4>
</div>
<script>cdtd();</script>
</div>
CSS
body {
margin: 0;
padding: 0;
background-image: repeating-linear-gradient(
90deg,
#FFFFFF,
#FFFFFF 18px,
#CA1D20 0px,
#CA1D20 28px
);
}
h1{
font-size: 64px;
text-align: center;
color: #3498db;
text-shadow: 3px 3px 0px #000;
}
h2{
font-size: 32px;
text-align: center;
color: #3498db;
text-shadow: 3px 3px 0px #000;
margin: auto;
}
.jumbotron.timer{
width: 48%;
height: 360px;
margin: auto;
background-color: #669900;
}
.timertxt{
color: #3498db;
text-shadow: 3px 3px 0px #000;
font-size: 64px;
padding-left: 12px;
padding-right: 12px;
border: 2px solid #2980b9 ;
border-radius: 5px;
background-color: #2980b9;
text-align: center;
}
.space{
font-size: 12px;
display: inline-block;
float: left;
visibility: hidden;
}
.timertxtc{
width: 25%;
height: 120px;
float: left;
display: inline-block;
margin: auto;
}
h4{
font-size: 32px;
color: #3498db;
text-shadow: 3px 3px 0px #000;
display: inline-block;
text-align: center;
}

Answer 1

The character in your <h3 class="space">1</h3> elements was causing the content of the container div to exceed 100% pushing 'seconds' on to the next line.
See fixes in the following fiddle:
https://jsfiddle.net/oLncm9d2/4/
Instead of using an element for 'spacing' padding-right / padding-left in combination with box-sizing: border-box; can achieve the spacing you want, without disrupting width calculations. (The solution demonstrates this and has removed the <h3 class="space">1</h3> elements.)
Note: I increased the container width to prevent excessive overlap for demonstration.