/* Professional AdSense-ready Design */
body {
    font-family: 'Roboto', sans-serif;
    background-color: #f8fafc;
    color: #334155;
    line-height: 1.6;
    margin: 0;
    padding: 0;
}
.container {
    max-width: 800px;
    margin: 20px auto;
    background: #ffffff;
    padding: 30px;
    border-radius: 12px;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
}
h1, h2 { color: #0f172a; }
input, button {
    width: 100%;
    padding: 12px;
    margin: 10px 0;
    border: 1px solid #cbd5e1;
    border-radius: 6px;
    box-sizing: border-box;
}
button {
    background-color: #3b82f6;
    color: white;
    font-weight: bold;
    cursor: pointer;
    border: none;
}
button:hover { background-color: #2563eb; }
.result {
    padding: 20px;
    background: #eff6ff;
    border-left: 5px solid #3b82f6;
    margin: 20px 0;
    font-size: 1.2em;
    font-weight: bold;
}
footer {
    text-align: center;
    margin-top: 40px;
    padding: 20px;
    font-size: 0.9em;
    color: #64748b;
}