*{
box-sizing:border-box;
}


body{

margin:0;
background:#111;
color:white;
font-family:Arial;

}


header{

display:flex;
justify-content:space-between;
padding:15px;
background:#1c1c1c;

}


.logo{

font-size:25px;
font-weight:bold;

}


nav a{

color:white;
margin:10px;
text-decoration:none;

}



.container{

padding:20px;

}



.box{

background:#222;
padding:30px;
border-radius:15px;
text-align:center;

}



.btn{

display:inline-block;
background:#00c853;
padding:12px 25px;
color:white;
border-radius:10px;
text-decoration:none;

}



footer{

text-align:center;
padding:20px;

}