Hi,
to style the button you can add following CSS code to your template:
.zocial.googleplus {
background-color: #fff;
color:black;
text-shadow:none;
border:1px solid #ccc;
}
.zocial.googleplus:before {
background:url("data:image/svg+xml;base64,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");
background-repeat: no-repeat;
background-position: center center;
background-size:14px;
content: "";
width: 30px;
height: 24px;
}
To change the text "Google+" unfortunately the best way is to change 2 lines of code in file /plugins/jsn/socialconnect/socialconnect.php: - At lines 2153 and 2154 replace "Google+" with "Google"