body {
font-family: Arial, sans-serif;
line-height: 1.6;
margin: 20px;
background-color: #f8f9fa;
color: #212529;
}

article {
max-width: 700px;
margin: 0 auto;
background-color: #ffffff;
padding: 25px 30px;
border-radius: 8px;
box-shadow: 0 0 10px rgba(0,0,0,0.1);
}

h1 {
font-size: 2.2rem;
margin-bottom: 0.4em;
color: #2c3e50;
}

h2 {
font-size: 1.5rem;
margin-top: 1.6em;
margin-bottom: 0.6em;
color: #34495e;
}

p {
font-size: 1rem;
margin-bottom: 1em;
color: #495057;
}

ul {
margin-left: 20px;
margin-bottom: 1em;
color: #495057;
}

label {
display: block;
margin-top: 1em;
font-weight: 600;
color: #2c3e50;
}

input[type="number"],
select {
width: 100%;
padding: 8px 10px;
margin-top: 6px;
border: 1px solid #ced4da;
border-radius: 4px;
font-size: 1rem;
box-sizing: border-box;
}

button {
margin-top: 20px;
background-color: #007bff;
color: #fff;
border: none;
padding: 12px 20px;
font-size: 1.1rem;
border-radius: 5px;
cursor: pointer;
width: 100%;
transition: background-color 0.3s ease;
}

button:hover {
background-color: #0056b3;
}

#result {
font-size: 1.3rem;
color: #1c7ed6;
}

a {
color: #007bff;
text-decoration: none;
}

a:hover {
text-decoration: underline;
}