* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    display: flex;
    justify-content: center;
    min-height: 100vh;
    background-color: #031c30;
    position: relative;
}

.contenedor {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 10px;

}

.titulo {
    color: #0e8d94;
    font-size: 50px;
    font-weight: 800;
    font-family: sans-serif;
    margin-top: 60px;
    margin-bottom: 60px;
}

.calculadora {
    background-color: #394240;
    padding: 15px;
    border-radius: 10px;
}

#pantalla {
    width: 100%;
    background-color: #111;
    color: #cec7b6;
    text-align: right;
    padding: 10px;
    font-size: 24px;
}

.botones {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 8px;
    margin-top: 10px;
}

.btn-num, .btn-op, .btn-igual, .btn-decimal{
    padding: 10px;
    font-size: 25px;
    cursor: pointer;
    border: none;
    border-radius: 8px 1px;
}

.btn-num {
    background-color: #939473;
    color: #222;
}

.btn-op {
    background-color: #353626;
    color: #ccc;
}

.btn-op-C {
    padding: 14px;
    font-size: 28px;
    cursor: pointer;
    border: none;
    border-radius: 9px 1px;
    background-color: #400;
    color: #a00;
}

.btn-igual {
    background-color: #353626;
    color: #ccc;
    grid-column: span 4;
}

.btn-decimal {
    background-color: #939473;
    color: #222;
}

.footer {
    position: fixed;
    bottom: 0;
    left: 0;
    width: 100%;
    background-color: #051525;
    padding: 10px;
    text-align: center;
    color: #067;
    font-size: 12px;
}