How to make it responsive using css - css

Question

Below code is my css and i'm trying to add an icon using another css but the icon css is not responsive how can i make it responsive.
.iconbox-singleD1 {
background: rgba(160, 215, 231, 0.85);
border-radius: 8px;
padding: 25px 20px;
margin-bottom: 30px;
-webkit-border-radius: 8px;
box-shadow: 0px 2px 20px rgba(74, 141, 245, 0.2);
-webkit-box-shadow: 0px 2px 20px rgba(74, 141, 245, 0.2);
-ms-flex-pack: justify;
justify-content: space-between;
flex-wrap: wrap;
position: relative;
display: flex;
align-items: center;
border-radius: 24px;
}
.iconbox-singleD1.active:before{
opacity:1;
}
.iconbox-singleD1:before{
content: "";
position: absolute;
top: 100%;
left: 21px;
right: 21px;
height: 6px;
border-radius: 0 0 6px 6px;
background: rgb(209 243 253 / 85%);
/* opacity: 0;
-webkit-transition: opacity .25s;
-o-transition: opacity .25s; */
transition: opacity .25s;
}
.iconbox-singleD1.iconbox-singl {
background: #fff;
margin-bottom: 30px;
justify-content: space-between;
flex-wrap: wrap;
position: relative;
display: flex;
align-items: center;
background: #FFFFFF;
}
.iconbox-singleD1 .box-title {
position: relative;
display: flex;
align-items: center;
justify-content: center;
}
.iconbox-singleD1 p {
margin: 0 0 5px 0;
/* text-transform: uppercase; */
font-weight: 400;
font-size: 14px;
/* color: #0d1f3c; */
color: #fff;
}
.iconbox-singleN1 h5 {
margin: 0;
font-size: 30px;
font-weight: 500;
color: #0d1f3c;
}
And this is the html skeleton. Here I'm using another css for icon div tag how can i combine with the above css to make it responsive.
<div class="col-lg-6">
<div class="iconbox-singleD1">
<div class="box-title">
<div>
<p>New Patients</p>
<h5 class="Dashboard-header-color">{{todaysAppointment}}</h5>
</div>
<div class="padLeftIcon">
<mat-icon>hotel</mat-icon>
</div>
</div>
</div>
</div>
and this is the css i use in icon div tag
.padLeftIcon{
position: absolute;
left: 173px;
width: 100%;
height: 100%;
}

Answer 1

You can use font-size in em e.g. font-size: 1.2em;
Working example link: https://jsfiddle.net/waqasahmad724/1ybxtp39/2/