/* ==========================================
   RESET E CONFIGURAÇÕES BÁSICAS
   ========================================== */
* { 
    box-sizing: border-box; 
    margin: 0; 
    padding: 0; 
}

/* ==========================================
   VARIÁVEIS DE TEMA (CLARO / ESCURO)
   ========================================== */
:root {
    --bg-color: #f4f7f9;
    --text-color: #2d3436;
    --card-bg: #ffffff;
    --border-color: #e2e8f0;
    --accent-color: #0056b3;
    --accent-hover: #003d80;
    --header-bg: #ffffff;
}

[data-theme="dark"] {
    --bg-color: #1a1a1a;
    --text-color: #f4f7f9;
    --card-bg: #2d2d2d;
    --border-color: #404040;
    --accent-color: #3b82f6;
    --accent-hover: #2563eb;
    --header-bg: #242424;
}

body {
    font-family: 'Segoe UI', Arial, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.6;
    transition: background 0.3s ease, color 0.3s ease;
}

/* Tipografia Global respeitando o tema */
h1, h2, h3, p {
    color: var(--text-color);
}

/* ==========================================
   HEADER E LOGO
   ========================================== */
header { 
    background-color: var(--header-bg); 
    padding: 30px 20px; 
    text-align: center; 
    border-bottom: 3px solid var(--accent-color);
    transition: background 0.3s ease;
}

.logo-container img { 
    max-width: 180px; 
    height: auto; 
    margin-bottom: 15px; 
    display: block;
    margin-left: auto;
    margin-right: auto;
}

/* ==========================================
   CONTAINER PRINCIPAL
   ========================================== */
main { 
    max-width: 1000px; 
    margin: 40px auto; 
    padding: 0 20px; 
}

/* ==========================================
   GRID DE CARDS (LIVROS & PROJETOS)
   ========================================== */
.book-list { 
    display: grid; 
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); 
    gap: 30px; 
    margin-top: 20px;
}

.book-card { 
    background-color: var(--card-bg); 
    border: 1px solid var(--border-color);
    border-radius: 12px; 
    overflow: hidden;
    box-shadow: 0 4px 10px rgba(0,0,0,0.05); 
    transition: transform 0.3s ease, box-shadow 0.3s ease, background-color 0.3s ease; 
    display: flex;
    flex-direction: column;
    text-align: left;
}

.book-card:hover { 
    transform: translateY(-5px); 
    box-shadow: 0 8px 20px rgba(0,0,0,0.12);
}


/* Imagens / Capas dos Cards (Padronizadas e Proporcionais) */
.book-thumb {
    width: 100%;
    height: 180px;          /* Fixa uma altura limpa para todos os cards */
    object-fit: cover;      /* Garante que a imagem preencha o espaço sem distorcer */
    object-position: center;/* Centraliza o corte da imagem */
    display: block;
    border-bottom: 1px solid var(--border-color);
}
/* Conteúdo interno do Card */
.book-content {
    padding: 25px;
    display: flex;
    flex-direction: column;
    flex-grow: 1;
}

.book-content h3 {
    font-size: 1.15rem;
    margin-bottom: 10px;
    font-weight: 700;
}

.book-content p {
    font-size: 0.95rem;
    opacity: 0.85;
    margin-bottom: 20px;
    flex-grow: 1;
}

/* ==========================================
   BOTÕES DE AÇÃO E TEMA
   ========================================== */
.cta-button { 
    display: inline-block; 
    text-align: center;
    padding: 12px 20px; 
    background-color: var(--accent-color); 
    color: #ffffff; 
    text-decoration: none; 
    border-radius: 6px; 
    font-weight: 600; 
    font-size: 0.95rem;
    transition: background-color 0.3s ease; 
}

.cta-button:hover { 
    background-color: var(--accent-hover); 
}

/* Botão Flutuante de Tema (Modo Escuro / Claro) */
.theme-btn {
    position: fixed;
    top: 20px;
    right: 20px;
    padding: 10px 12px;
    cursor: pointer;
    background: var(--accent-color);
    color: white;
    border: none;
    border-radius: 8px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.2);
    z-index: 1000;
    transition: background 0.3s ease, transform 0.2s ease;
}

.theme-btn:hover {
    transform: scale(1.05);
    background-color: var(--accent-hover);
}

#toggleTheme {
    cursor: pointer;
    padding: 8px 12px;
    border-radius: 20px;
    border: 1px solid var(--border-color);
    background: var(--card-bg);
    color: var(--text-color);
    transition: transform 0.2s ease, background 0.3s ease;
}

#toggleTheme:hover {
    transform: scale(1.05);
    background-color: var(--accent-color);
    color: white;
}

/* ==========================================
   RODAPÉ
   ========================================== */
.footer {
    text-align: center;
    padding: 40px 20px;
    background-color: var(--card-bg);
    border-top: 1px solid var(--border-color);
    margin-top: 60px;
    transition: background 0.3s ease;
}