.fixed_btn { 
    position: fixed;
    z-index:900;
    bottom: 100px;
    right: 10px;
}
.fixed_btn  a { 
    position:relative;
    display:block;
    padding: 12px 18px;
    border-radius:4%;
    /*background:rgba(100,100,100, 0.75);*/
    background:rgba(0,129,192, 0.70); 
    transition:0.4s;
    
    color:#fff;
    font-size: 14px;
    line-height:1.5em;
    text-align: center;
}

.fixed_btn  a:hover { 
    background:rgba(0,114,167, 0.85);
}

@media screen and (max-width: 768px){
.fixed_btn { 
    bottom: 0px;
    left: 0px;
    text-align: center;
}
.fixed_btn  a { 
    width:50%;
    border-radius:0%;
    background:rgba(0,129,192, 0.90); 
    border-radius: 0px 20px 0px 0px;
}
}