Font awesome, same icon with different width

Question

I have a little problem with Font Awesome icon.

I have 2 same versions of website (for development and tests) and the icon displays differently while having same CSS styles.

I described this problem with this icon:

.btnFilter {
    color: #666666;
    padding-top: 4px;
    font-size: 18px;
    text-align: center;
}
.circle {
    border: solid #999 1px;
    border-radius: 13px;
    box-sizing: border-box;
    width: 26px;
    height: 26px;
    text-align: center;
    font-size: 18px;
}

<link href="https://maxcdn.bootstrapcdn.com/font-awesome/4.5.0/css/font-awesome.min.css" rel="stylesheet"/>

<i class="fa fa-times circle btnFilter"></i>

This CSS and HTML markup is placed on both dev and test versions, chrome dev tools displays same styles, and hovering font-awesome icon :before pseudoelement's size gives result as on the image above.

Answer 1

I think you would be better served by using em rather than px values here...then everything adjusts to the font size.

As to your specific issue, there is a clash between line-height/font-size in font-awesome and your specific styles.

The top padding is also probably not required.

html {
  box-sizing: border-box;
}
*,
*::before,
*::after {
  box-sizing: inherit;
  margin: 0;
  padding: 0;
}
.btnFilter {
  color: #666666;
  font-size: 160px !important;
  /* for demo only */
  line-height: 1em;
  text-align: center;
}
.fa::before {
  line-height: inherit;
}
.circle {
  border: solid #999 1px;
  border-radius: 50%;
  width: 1.1em;
  height: 1.1em;
}

<link href="https://maxcdn.bootstrapcdn.com/font-awesome/4.5.0/css/font-awesome.min.css" rel="stylesheet" />
<i class="fa fa-times circle btnFilter"></i>

Codepen Demo

Answer 2

I believe it has to do with the font-size. I think its because font-awesome has a declaration of

    font: normal normal normal 14px/1 FontAwesome;

So remove the font-size or adjust your font-size using em and it should work as expected

if you add !important to your font-size you will see the weird result that you see on one of your sites.

.btnFilter {
    color: #666666;
    padding-top: 4px;
    font-size: 18px !important;
    text-align: center;
}
.circle {
    border: solid #999 1px;
    border-radius: 13px;
    box-sizing: border-box;
    width: 26px;
    height: 26px;
    text-align: center;
    font-size: 18px !important;
}

<link href="https://maxcdn.bootstrapcdn.com/font-awesome/4.5.0/css/font-awesome.min.css" rel="stylesheet"/>

<i class="fa fa-times circle btnFilter"></i>

Or you could do this

.circle{
    width:18px;
    height:18px;
    padding: 3px;
    background-color:white;
    border-radius:100%;
    line-height:18px;
    text-align:center;
    vertical-align:middle;
    display:inline-block;
    border: solid #999 1px;
}

.btnFilter { 
  line-height: inherit; 
  font-size: 18px;
  color: #666666;
}

<link href="https://maxcdn.bootstrapcdn.com/font-awesome/4.5.0/css/font-awesome.min.css" rel="stylesheet"/>

<div class="circle">
  <i class="fa fa-times btnFilter"></i>
</div>