How to stop link colour and underline Options

[mattykg1987]

As the title states how do i stop link colour and underline when hovering over or allready clicking on it this is the code i have for it in my css.

header{text-align: center;background: #fff;}
header .top-header{background: #292A2C;color: #fff;}
header .top-header i.fa{margin: 5px 2px 0;}

.logo {color: #333;padding: 20px 0 30px; }
.logo a{font-family: 'Dancing Script', cursive;font-size: 80px;color: #333;font-weight: bold;display: block;line-height: 1.3; }
.logo span{font-size: 16px;letter-spacing: 1px;}
@media(max-width:767px){
.logo{padding: 30px 0 20px;}
.logo a{font-size: 65px;}
.logo span{font-size: 16px;}
}

Thanks to anyone that can help.