* {
    box-sizing: border-box;
    }

body {
    font-family: "Segoe UI", sans-serif;
    background-color: #0f172a;
    margin: 0;
    padding: 20px;
    }

h1 {
    text-align: center;
    color: #fcfdfd;
    font-size: 1.8em;
    }

.container {
    max-width: 600px;
    margin: auto;
    background: #fff;
    padding: 25px;
    border-radius: 12px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
    }

label {
    display: block;
    margin: 15px 0 5px;
    font-weight: 600;
    font-size: 0.95em;
    }

input[type="number"] {
    width: 100%;
    padding: 12px;
    font-size: 1em;
    border-radius: 8px;
    border: 1px solid #ccc;
    background-color: #fafafa;
    }

button {
    margin-top: 20px;
    background-color: #3498db;
    color: white;
    padding: 14px;
    width: 100%;
    border: none;
    border-radius: 8px;
    font-size: 1em;
    cursor: pointer;
    transition: background 0.3s ease;
    }

button:hover {
    background-color: #2980b9;
    }

.result {
    margin-top: 30px;
    padding: 20px;
    background: #ecf0f1;
    border-radius: 8px;
    }

.result h2 {
    color: #27ae60;
    margin-bottom: 10px;
    }

.result p {
    margin: 8px 0;
    font-size: 0.95em;
    }

@media (max-width: 600px) {
    body {
        padding: 10px;
    }

.container {
        padding: 20px 15px;
    }

    h1 {
        font-size: 1.5em;
    }

    label {
        font-size: 0.9em;
    }

    input,
    button {
        font-size: 0.95em;
    }

.result p {
        font-size: 0.9em;
    }
    }