Tornado Uses 4 main background colors primary color and its hover color secondary color and its hover you can customized easly by 4 line of code and also using standard colors with class like success,danger,warning etc..
/*======= Colors Customize =======*/
.primary-bg,.primary-bg-hoverable{
background:#3498db;
}
.primary-bg-hoverable:hover{
background:#2980b9;
}
.primary-text,.primary-text-hoverable{
color:#3498db;
}
.primary-text-hoverable:hover{
color:#2980b9;
}
.secondary-bg,.secondary-bg-hoverable{
background:#34495e;
}
.secondary-bg-hoverable:hover{
background:#2c3e50;
}
.secondart-text,.secondart-text-hoverable{
color:#34495e;
}
.secondart-text-hoverable:hover{
color:#2c3e50;
}