Change Icon with Icon

We added a fontello icon but you can replace with a fontawesome icon h

i.demo-icon.icon-lock-1:before {
content: "\f043";
font: normal normal normal 14px/1 FontAwesome;
margin-right: 7px;
font-size: 20px;
}

The icon code – f043 – you can take from fontawesome 4 – https://fontawesome.com/v4.7.0/icons/

Change Icon with Text

.submit_action:before {
border: 1px solid green;
content: "LOGIN";
font-size: 19px;
background-color: green;
color: red;
}

.demo-icon.icon-lock-1 {
display: none;
}

.submit_action:hover::before {
    background: #000000;
    border: 6px solid #000000;
}

Help to add custom css

http://help.wpresidence.net/article/how-to-add-custom-css/​