The very famous Font Awesome’s font has the ability to resize its icons, for example, to be displayed in white or red, you can use CSS to define this feature for this set of functional fonts. Note the following:

<i class="fa fa-check-circle-o fa-5x" style="color:green"></i>

In the above code, 5 x size and color define the color property. This way you can change the desired size and color of the icons within your html code.

Another way is to use style in the css file.

HTML

<i class="fa fa-facebook"></i> 

CSS

i.fa {
    color: red;
    font-size: 30px;
}

Search for the desired icon in the following two sites;