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

/* Fundo geral */
body {
    font-family: "Segoe UI", sans-serif;
    background: #111;
    color: #fff;
}

/* HEADER com bear.png */
header {
    background: url('bear.png') center/cover no-repeat;
    height: 350px;
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
}

/* Camada translúcida por cima da imagem */
.header-overlay {
    background: rgba(0, 0, 0, 0.55);
    padding: 40px 60px;
    border-radius: 20px;
    backdrop-filter: blur(8px);
    text-align: center;
}

header h1 {
    font-size: 3.2rem;
    letter-spacing: 2px;
}

header p {
    font-size: 1.4rem;
    opacity: 0.9;
}

/* GRID dos livros */
.books {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 35px;
    padding: 40px;
}

/* CARD estilo moderno */
.book-card {
    background: rgba(255,255,255,0.08);
    border-radius: 18px;
    padding: 20px;
    text-align: center;
    backdrop-filter: blur(10px);
    box-shadow: 0 8px 25px rgba(0,0,0,0.4);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.book-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 12px 35px rgba(0,0,0,0.6);
}

.book-card img {
    width: 100%;
    border-radius: 12px;
    margin-bottom: 15px;
}

/* Botões */
button {
    padding: 12px 20px;
    background: #c49a6c;
    border: none;
    border-radius: 10px;
    font-weight: bold;
    cursor: pointer;
    transition: background 0.3s ease;
}

button:hover {
    background: #e6c89c;
}

.book-card.disabled {
    opacity: 0.45;
}

.book-card.disabled button {
    background: #555;
    cursor: not-allowed;
}

/* Rodapé */
footer {
    text-align: center;
    padding: 25px;
    background: rgba(255,255,255,0.05);
    backdrop-filter: blur(6px);
    margin-top: 40px;
    font-size: 1rem;
}