body {
    font-family: 'Trebuchet MS', Helvetica, sans-serif; 
    font-size: 17px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: #333;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    margin: 0;
}
.converter {
    background: white;
    padding: 15px;
    border-radius: 5px;
    box-shadow: 0 4px 20px rgba(0,0,0,0.1);
    max-width: 400px;
    width: 100%;
}
h1 {
    text-align: center;
    color: #667eea;
    margin: 10px 0;
    font-size: 27px;
}
input, select, button {
    width: 100%;
    padding: 8px;
    margin: 10px 0;
    border: 1px solid #ddd;
    border-radius: 5px;
    box-sizing: border-box;
    font-family: Verdana, Geneva, sans-serif;
    font-size: 14px;
}
button {
    background: #667eea;
    color: white;
    cursor: pointer;
    margin-bottom: 0;
}
button:hover {
    background: #5a67d8;
}
#result {
    font-weight: bold;
    text-align: center;
    margin-top: 15px;
}