body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: #444444;
    color: #fff;
    padding: 0;
    margin: 0;
}

.container {
    background-color: #2b2b2b;
    padding: 20px;
    border-radius: 10px;
    max-width: 800px;
    margin: auto;
    box-shadow: 0 0 15px rgba(0, 0, 0, 0.3);
}

h2 {
    margin: 0;
    text-align: center;
    color: #fff;
}

label {
    font-weight: bold;
    margin-top: 20px;
    display: block;
}

select,
input[type="number"] {
    width: 100%;
    padding: 10px;
    margin-top: 5px;
    border: 1px solid #1d1d1d;
    border-radius: 5px;
    box-sizing: border-box;
    font-size: 16px;
    background-color: #1d1d1d;
    color: #fff;
}

button {
    margin-top: 25px;
    padding: 12px 20px;
    font-size: 16px;
    background-color: #00913a;
    border: none;
    color: white;
    border-radius: 5px;
    cursor: pointer;
    width: 100%;
}

button:hover {
    background-color: #009c3f;
}

#wynik,
#dodatkowe {
    background-color: #1d1d1d;
    color: #fff;
    padding: 20px;
    margin-top: 30px;
    border-radius: 10px;
}

table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 10px;
}

table th,
table td {
    border: 1px solid #000000;
    padding: 8px;
    text-align: left;
}

table th {
    background-color: #000000;
}

.highlight {
    background-color: #880000;
    font-weight: bold;
}

#copyright {
    text-align: center;
    margin-top: 20px;
    font-size: 14px;
    color: #aaa;
}