/* Estilos gerais */
body {
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    margin: 0;
    background-color: #f0f0f0;
    font-family: Arial, sans-serif;
    flex-direction: column; /* Alinha a calculadora e o tutorial verticalmente */
}

/* Container da calculadora */
.calculator {
    background-color: #333;
    border-radius: 10px;
    padding: 20px;
    box-shadow: 0px 0px 20px rgba(0, 0, 0, 0.5);
    width: 700px; /* Largura maior para acomodar mais botões */
    border: 2px solid #000; /* Borda da calculadora */
    margin-bottom: 20px; /* Espaço entre a calculadora e o tutorial */
}

/* Logo da HP */
.hp-logo {
    text-align: center;
    font-size: 24px;
    font-weight: bold;
    color: #fff;
    font-family: 'Courier New', monospace;
    margin-bottom: 20px;
}

.hp-logo span {
    color: #ffaa00; /* Laranja da HP */
}

/* Display da calculadora */
#display {
    width: 100%;
    height: 50px;
    background-color: #c0c0c0;
    border: 2px solid #000; /* Borda do display */
    border-radius: 5px;
    text-align: right;
    padding: 10px;
    font-size: 24px;
    color: #000;
    margin-bottom: 20px;
    box-sizing: border-box;
    font-family: 'Courier New', monospace;
    transition: opacity 0.5s ease-in-out; /* Transição suave */
}

/* Placeholder translúcido */
#display::placeholder {
    opacity: 0.5; /* Translúcido */
    transition: opacity 0.5s ease-in-out;
}

/* Esconde o placeholder quando a calculadora está desligada */
#display.power-off::placeholder {
    opacity: 0;
}

/* Estilo para as mensagens de boas-vindas e despedida */
#display.message {
    font-family: 'Georgia', serif;
    font-style: italic;
    font-size: 20px;
    text-align: center;
}

/* Botões da calculadora */
.buttons {
    display: grid;
    grid-template-columns: repeat(8, 1fr); /* 8 colunas para mais botões */
    gap: 10px;
}

.btn {
    background-color: #555;
    color: #fff;
    border: 2px solid #000; /* Borda dos botões */
    border-radius: 5px;
    padding: 15px;
    font-size: 18px;
    cursor: pointer;
    transition: background-color 0.1s, transform 0.1s;
}

.btn:hover {
    background-color: #777; /* Apenas muda a cor de fundo ao passar o mouse */
}

.btn.active {
    transform: scale(0.95); /* Efeito de pressionar */
}

/* Botão de Liga/Desliga */
.btn[data-value="power"] {
    background-color: #666;
    grid-column: span 2; /* Ocupa duas colunas */
}

/* Botão de Ajuda */
.btn[data-value="help"] {
    background-color: #444;
    grid-column: span 2;
}

/* Botões especiais */
.btn[data-value="C"] {
    background-color: #ff4444;
}

.btn[data-value="="] {
    background-color: #44cc44;
    grid-column: span 2;
}

.btn[data-value="/"],
.btn[data-value="*"],
.btn[data-value="-"],
.btn[data-value="+"] {
    background-color: #ffaa00;
}

/* Botões científicos */
.btn[data-value="√"],
.btn[data-value="^"],
.btn[data-value="log"],
.btn[data-value="sin"],
.btn[data-value="cos"],
.btn[data-value="tan"],
.btn[data-value="arcsin"],
.btn[data-value="arccos"],
.btn[data-value="arctan"],
.btn[data-value="ln"],
.btn[data-value="exp"],
.btn[data-value="∛"],
.btn[data-value="!"],
.btn[data-value="%"],
.btn[data-value="π"],
.btn[data-value="e"],
.btn[data-value="sinh"],
.btn[data-value="cosh"],
.btn[data-value="tanh"],
.btn[data-value="deg2rad"],
.btn[data-value="rad2deg"],
.btn[data-value="mod"],
.btn[data-value="10^x"],
.btn[data-value="abs"],
.btn[data-value="rand"],
.btn[data-value="ceil"],
.btn[data-value="floor"],
.btn[data-value="round"] {
    background-color: #666;
}

/* Botões numéricos */
.btn[data-value="0"],
.btn[data-value="1"],
.btn[data-value="2"],
.btn[data-value="3"],
.btn[data-value="4"],
.btn[data-value="5"],
.btn[data-value="6"],
.btn[data-value="7"],
.btn[data-value="8"],
.btn[data-value="9"] {
    background-color: #444;
}

/* Janela de Ajuda */
.help-window {
    background-color: #444;
    color: #fff;
    border-radius: 5px;
    padding: 20px;
    width: 700px;
    box-shadow: 0px 0px 20px rgba(0, 0, 0, 0.5);
    display: none; /* Inicialmente oculta */
    margin-top: 20px;
}

.help-window h2 {
    margin-top: 0;
    font-size: 24px;
    color: #ffaa00;
}

.help-window ul {
    list-style-type: none;
    padding: 0;
}

.help-window li {
    margin-bottom: 10px;
    font-size: 16px;
}

.help-window li strong {
    color: #ffaa00;
}