.maincontent {
    position: relative;
    max-width: 100%;
}

a.btn.btn-primary {    padding: 16px 28px;    border-radius: 0;    background: #000;    border: none;   box-shadow: 0 4px 5px -3px #333;    transition: 0.5s;    font-weight: bold;transition: ease-out 0.4s;}
a.btn.btn-primary:hover {    box-shadow: inset 0 0 0 50px #4c4c4d; }


.tab-content{
background: #fff;
padding: 50px;
}


.nav-tabs > li > a{
color: #fff;
font-size: 24px;
}

.nav-tabs > li > a:hover{
background: #000;
}