body {
    font-family: 'Arial', sans-serif;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    margin: 0;
    background-color: #f0f2f5;
}

.container {
    text-align: center;
    background: white;
    padding: 2rem;
    border-radius: 15px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.1);
}

#resultado {
    font-size: 8rem;
    font-weight: bold;
    color: #007bff;
    margin: 20px 0;
    min-width: 150px;
}

button {
    padding: 10px 25px;
    font-size: 1.2rem;
    cursor: pointer;
    background-color: #28a745;
    color: white;
    border: none;
    border-radius: 5px;
    transition: transform 0.1s;
}

button:active {
    transform: scale(0.95);
}

/* Estilo para o histórico no topo */
#historico {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    min-height: 50px;
    background: #e9ecef;
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    padding: 15px;
    box-sizing: border-box;
    justify-content: center;
    border-bottom: 2px solid #ddd;
}

.letra-usada {
    background: #007bff;
    color: white;
    padding: 5px 12px;
    border-radius: 20px;
    font-weight: bold;
    font-family: sans-serif;
    animation: fadeIn 0.3s ease;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(-10px); }
    to { opacity: 1; transform: translateY(0); }
}

/* O resto do CSS anterior permanece igual... */
body { font-family: Arial; display: flex; justify-content: center; align-items: center; height: 100vh; margin: 0; background-color: #f0f2f5; }
.container { text-align: center; background: white; padding: 2rem; border-radius: 15px; box-shadow: 0 4px 15px rgba(0,0,0,0.1); }
#resultado { font-size: 8rem; font-weight: bold; color: #007bff; margin: 20px 0; }
button { padding: 10px 25px; font-size: 1.2rem; cursor: pointer; background-color: #28a745; color: white; border: none; border-radius: 5px; }
button:disabled { background-color: #ccc; cursor: not-allowed; }