*{
    margin: 0;
    padding: o;
}
header{
    padding-top: 30px;
}
header > h1{
    padding: 10px 10px;
}
a{   
    margin-top: 60px;
    text-decoration: none;
    font-weight: 600;
    color: white;
}
a:hover{
    color: black;
}
.fundo{
    background-image: linear-gradient(45deg,rgb(0, 0, 0),#6E7B8B);
    height: 100vh;
    color: white;
    font-family: Arial, Helvetica, sans-serif;
    text-align: center;
}
.calculadora{
position: absolute;
background-color: rgba(0, 0, 0, 0.8);
top: 50%;
left: 50%;
transform: translate(-50%,-50%); 
border-radius: 15px;
padding: 15px;
box-shadow: 5px 3px 3px black;
}
.botao{
    margin: 3px;
    width: 50px;
    height: 50px;
    font-size: 25px;
    cursor: pointer;
    background-color: rgb(31, 31, 31);
    border: none;
    color: #fff;
}
.botao:hover{
    background-color: black;
}
#resultado{
    background-color: white;
    width: 220px;
    height: 30px;   
    margin: 5px;
    font-size: 25px;
    color: black;
    text-align: right;
    padding: 5px;
    font-family:Arial, Helvetica, sans-serif;
    font-weight: bold;

    
    
}