* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Roboto', Arial, sans-serif;
}

body {
    background-color: #121212;
    color: #e8eaed;
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 20px;
}

main {
    width: 100%;
    max-width: 360px;
}

.container h1 {
    font-size: 1.2rem;
    font-weight: 400;
    color: #9aa0a6;
    margin-bottom: 12px;
    text-align: center;
}

/* Card da Calculadora estilo Google */
.calculadora {
    width: 100%;
    background-color: #202124;
    border: 1px solid #3c4043;
    border-radius: 8px;
    border-collapse: separate;
    border-spacing: 8px;
    padding: 12px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.5);
}

/* Visor (Display) */
.display {
    width: 100%;
    height: 64px;
    background-color: #202124;
    border: 1px solid #3c4043;
    border-radius: 4px;
    color: #e8eaed;
    font-size: 2rem;
    text-align: right;
    padding: 0 12px;
    outline: none;
}

/* Estilizacao padrao dos botoes */
.btn {
    width: 100%;
    height: 48px;
    background-color: #3c4043;
    color: #e8eaed;
    border: none;
    border-radius: 4px;
    font-size: 1.1rem;
    font-weight: 500;
    cursor: pointer;
    transition: background-color 0.15s ease, transform 0.05s ease;
}

.btn:hover {
    background-color: #4a4e51;
}

.btn:active {
    transform: scale(0.97);
}

.btn-num{
    background-color: #3c4043;
}

/* Botão de Igual (=) - Destaque Azul Google */
tr:last-child td:last-child .btn {
    background-color: #8ab4f8;
    color: #202124;
    font-weight: bold;
}

tr:last-child td:last-child .btn:hover {
    background-color: #aecbfa;
}

/* Botão de Limpar (C) */
.btn-clear {
    background-color: #303134;
    color: #f28b82;
}

.btn-clear:hover {
    background-color: #3c4043;
}

/* Responsividade para telas muito pequenas */
@media (max-width: 320px) {
    .calculadora {
        border-spacing: 4px;
        padding: 8px;
    }
    
    .btn {
        height: 42px;
        font-size: 1rem;
    }
    
    .display {
        height: 52px;
        font-size: 1.6rem;
    }
}