*{
    background:  white;
    font-family:  'Times New Roman', Times, serif;
	
}
.nav-list{
    list-style-type: none;
    margin: -10px;
    padding: 0;
    overflow: hidden;
	background-color: black;
}
.nav-list li a{
    display: block;
	color:white;
    text-align: center;
    padding: 14px 16px;
    text-decoration: none;
    float: right;
	background-color: black;
	margin:0;
}
.nav-list li a:hover{
    background-color:white;
    color: black;
}
.header{
    margin-top:40px;
    text-align: center;
    margin-bottom: 50px;
}
.calculation >button{
    color: #000000;
    background-color: #a19d9d;
}
.implem >button{
    color: #000000;
    background-color: #a19d9d;
}
footer {
    color:white;
    margin: -5px;;
    width: 100%;
    background-color:black;
	padding: 5px 10px;
}
footer p{
    background-color:black;
}

h4{
    font-size: 20px;
    font-family: 'Times New Roman', Times, serif;
}