*{
margin:0;
padding:0;
box-sizing:border-box;
font-family:Arial,sans-serif;
}

body{

background:#f4f7fc;
display:flex;
justify-content:center;
align-items:center;
height:100vh;

}

.container{

width:100%;
max-width:500px;
padding:20px;

}

.card{

background:#fff;
padding:30px;
border-radius:10px;
box-shadow:0 5px 20px rgba(0,0,0,.1);

}

h1{

text-align:center;
margin-bottom:10px;
color:#333;

}

.subtitle{

text-align:center;
margin-bottom:25px;
color:#777;

}

label{

display:block;
margin-bottom:10px;
font-weight:bold;

}

input{

width:100%;
padding:12px;
font-size:16px;
margin-bottom:20px;

}

button{

width:100%;
padding:14px;
background:#0d6efd;
color:white;
border:none;
border-radius:6px;
font-size:17px;
cursor:pointer;

}

button:hover{

background:#0b5ed7;

}

#result{

margin-top:25px;
text-align:center;
font-size:22px;
font-weight:bold;
color:#0d6efd;

}