@import url('https://fonts.googleapis.com/css2?family=Orbitron:wght@400;700&display=swap');

html, body {
    height: 100%;
}
body {
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: #f0f2f5;
}
.calculator-card {
    width: 22rem;
    border-radius: 15px;
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.1);
}
.calculator-screen {
    background-color: #222;
    color: #fff;
    font-size: 2.5rem;
    border-radius: 10px 10px 0 0;
    padding: 1.5rem 1rem;
    font-family: 'Orbitron', sans-serif;
}
.btn-custom {
    font-size: 1.5rem;
    margin: 5px;
    border-radius: 10px;
    box-shadow: 0 2px 5px rgba(0,0,0,0.2);
}
#footer {
		position: absolute;
		bottom: 10px;
		font-size: 0.9rem;
}