[css] Use Font Awesome Icons in CSS

I have some CSS that looks like this:

#content h2 {
   background: url(../images/tContent.jpg) no-repeat 0 6px;
}

I would like to replace the image with an icon from Font Awesome.

I do not see anyway to use the icon in CSS as a background image. Is this possible to do assuming the Font Awesome stylesheets/fonts are loaded before my CSS?

Consolidating everything above, the following is the final class which works well

   .faArrowIcon {
        position:relative;
    }

    .faArrowIcon:before {
        font-family: FontAwesome;
        top:0;
        left:-5px;
        padding-right:10px;
        content: "\f0a9"; 
    }

To use font awesome using css follow below steps -

step 1 - Add Fonts of FontAwesome in CSS

/*Font Awesome Fonts*/
@font-face {
    font-family: 'FontAwesome';
    //in url add your folder path of FontAwsome Fonts
    src: url('font-awesome/fontawesome-webfont.ttf') format('truetype');
}

Step - 2 Use below css to apply font on class element of HTML

.sorting_asc:after {
    content: "\f0de"; /* this is your text. You can also use UTF-8 character codes as I do here */
    font-family: FontAwesome;
    padding-left: 10px !important;
    vertical-align: middle;
}

And finally, use "sorting_asc" class to apply the css on desired HTML tag/element.

Use the following Python program via command line to create png images from Font-Awesome icons:

https://github.com/Pythonity/font-awesome-to-png

No need to embed content into the CSS. You can put the badge content inside the fa element, then adjust the badge css. http://jsfiddle.net/vmjwayrk/2/

<i class="fa fa-envelope fa-5x" style="position:relative;color:grey;">
  <span style="
        background-color: navy;
        border-radius: 50%;
        font-size: .25em;
        display:block;
        position:absolute;
        text-align: center;
        line-height: 2em;
        top: -.5em;
        right: -.5em;
        width: 2em;
        height: 2em;
        border:solid 4px #fff;
        box-shadow:0px 0px 1px #000;
        color: #fff;
    ">17</span>
</i>

Alternatively, if using Sass, one can "extend" FA icons to display them:

.mytextwithicon:before {
  @extend .fas, .fa-angle-double-right;

  @extend .mr-2; // using bootstrap to add a small gap
                 // between the icon and the text.
}

Actually even font-awesome CSS has a similar strategy for setting their icon styles. If you want to get a quick hold of the icon code, check the non-minified font-awesome.css file and there they are....each font in its purity.

You can try this example class. and find icon content here: http://astronautweb.co/snippet/font-awesome/

  #content h2:before {
    display: inline-block;
    font: normal normal normal 14px/1 FontAwesome;
    font-size: inherit;
    text-rendering: auto;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    transform: translate(0, 0);
    content: "\f007";
    }

For this you just need to add content attribute and font-family attribute to the required element via :before or :after wherever applicable.

For example: I wanted to attach an attachment icon after all the a element inside my post. So, first I need to search if such icon exists in fontawesome. Like in the case I found it here, i.e. fa fa-paperclip. Then I would right click the icon there, and go the ::before pseudo property to fetch out the content tag it is using, which in my case I found to be \f0c6. Then I would use that in my css like this:

   .post a:after {
     font-family: FontAwesome,
     content: " \f0c6" /* I added a space before \ for better UI */
    }

I am bit late to the part. Just like to suggest another way.

  button.calendar::before {
    content: '\f073';
    font-family: 'Font Awesome 5 Free';
    left: -4px;
    bottom: 4px;
    position: relative;
  }

position,left and bottom is used to align icon.

Sometimes adding font-weight 600 or above also helps.

#content h2:before {
    content: "\f055";
    font-family: FontAwesome;
    left:0;
    position:absolute;
    top:0;
}

Example Link: https://codepen.io/bungeedesign/pen/XqeLQg

Get Icon code from: https://fontawesome.com/cheatsheet?from=io

Further to the answer from Diodeus above, you need the font-family: FontAwesome rule (assuming you have the @font-face rule for FontAwesome declared already in your CSS). Then it is a matter of knowing which CSS content value corresponds to which icon.

I have listed them all here: http://astronautweb.co/snippet/font-awesome/