/* =========================================
   1. Variáveis e Cores (Tema Simples e Limpo)
   ========================================= */
:root {
    /* Fundo da página - cor sólida simples */
    --bg-color: #4a5568;
    
    /* Fundo do Bloco de Texto */
    --card-bg: #1a202c; 
    
    /* Cores do Texto */
    --text-color: #e2e8f0;      
    --text-muted: #a0aec0;      
    
    /* Cor de destaque */
    --primary-color: #fbbf24;   
    --primary-hover: #f59e0b;
    
    /* Header */
    --header-bg: #2d3748;
    --border-color: #4a5568;    
    
    --focus-color: #fbbf24;     
    --radius: 12px;
    --radius-sm: 6px;              
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.3);
}

/* Tema Alto Contraste (Segurança) */
body.high-contrast {
    --bg-color: #000000;
    --card-bg: #000000;
    --text-color: #ffffff;
    --text-muted: #dddddd;
    --primary-color: #ffff00;
    --primary-hover: #ffcc00;
    --header-bg: #000000;
    --border-color: #ffffff;
    --focus-color: #00ffff;
    --shadow-md: none;
}

body.high-contrast {
    background: #000000 !important;
}

/* =========================================
   2. Estrutura Geral
   ========================================= */
html {
    scroll-padding-top: 100px; /* Compensa a altura do header fixo */
}

body {
    font-family: 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    margin: 0;
    line-height: 1.6;
    min-height: 100vh;
}

.container {
    max-width: 1000px;
    margin: 0 auto;
    padding: 0 1.5rem;
}

/* Linha separadora dentro do texto */
hr {
    border: 0;
    border-top: 1px solid var(--border-color);
    margin: 2rem 0;
}

/* Vídeos responsivos */
.video-container {
    margin-top: 1rem;
    position: relative;
    padding-bottom: 56.25%; /* Proporção 16:9 */
    height: 0;
    overflow: hidden;
    border-radius: var(--radius);
    border: 1px solid var(--border-color);
}

/* Para iframes do YouTube */
.video-container iframe {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    border: none;
    border-radius: var(--radius);
}

/* Para vídeos locais */
.video-container video {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    border: none;
    border-radius: var(--radius);
    object-fit: contain;
}

/* =========================================
   3. Header Simples
   ========================================= */
header {
    background-color: var(--header-bg);
    border-bottom: 1px solid var(--border-color);
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: var(--shadow-md);
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center; /* Alinha tudo no centro verticalmente */
    flex-wrap: wrap;
    gap: 15px;
}

h1 {
    font-size: 1.5rem;
    font-weight: 600;
    margin: 0;
    color: var(--text-color);
}

h2 {
    font-size: 1.8rem;
    font-weight: 600;
    margin: 0 0 1rem 0;
    color: var(--text-color);
}

/* Navegação Horizontal */
nav ul {
    display: flex;
    gap: 15px;
    list-style: none;
    padding: 0;
    margin: 0;
}

nav a {
    color: #e2e8f0;
    text-decoration: none;
    font-size: 0.9rem;
    font-weight: 500;
    padding: 6px 12px;
    border-radius: var(--radius-sm);
    transition: color 0.2s ease;
}

nav a:hover {
    color: var(--primary-color);
}

/* Botões do Header */
.a11y-toolbar {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
}

.a11y-toolbar button {
    background: transparent;
    color: #ccc;
    border: 1px solid #555;
    padding: 6px 10px;
    font-size: 0.8rem;
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: all 0.2s ease;
}

.a11y-toolbar button:hover {
    border-color: var(--primary-color);
    color: var(--primary-color);
}

.a11y-toolbar button.reading-active {
    background: rgba(251, 191, 36, 0.2);
    border-color: var(--primary-color);
    color: var(--primary-color);
}

/* Ajustes Header Alto Contraste */
body.high-contrast nav a { color: #ffff00; }
body.high-contrast header { border-bottom: 1px solid #fff; }

/* =========================================
   4. Cards Simples
   ========================================= */
.card {
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    padding: 2.5rem;
    margin-top: 2rem;
    margin-bottom: 2rem;
    box-shadow: var(--shadow-md);
}

/* Alto Contraste no Card */
body.high-contrast .card {
    border: 2px solid #fff;
    box-shadow: none;
    background: #000000;
}

/* Parágrafos */
.card p {
    margin-bottom: 1rem;
    color: var(--text-color);
}

.card p:last-child {
    margin-bottom: 0;
}

/* Listas */
.card ul {
    padding-left: 1.5rem;
    margin: 1rem 0;
}

.card ul li {
    color: var(--text-color);
    margin-bottom: 0.5rem;
}

/* =========================================
   5. Acessibilidade (Skip Link & Focus)
   ========================================= */
.skip-link {
    position: absolute;
    top: -60px;
    left: 20px;
    background: var(--primary-color);
    color: #000;
    padding: 10px 15px;
    z-index: 2000;
    text-decoration: none;
    font-weight: bold;
    border-radius: 0 0 var(--radius-sm) var(--radius-sm);
    transition: top 0.3s;
}

.skip-link:focus { 
    top: 0;
}

/* Foco */
*:focus {
    outline: none;
    box-shadow: 0 0 0 2px var(--bg-color), 0 0 0 4px var(--focus-color);
}

/* Destaque de leitura */
.highlight-reading {
    background-color: rgba(251, 191, 36, 0.2);
    border: 1px solid var(--primary-color);
    border-radius: var(--radius-sm);
    padding: 2px;
}

.word-active {
    background-color: var(--primary-color);
    color: #000;
    font-weight: 600;
    padding: 2px 4px;
    border-radius: 4px;
}

/* Links */
.card a {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 500;
}

.card a:hover {
    text-decoration: underline;
}

/* Main content area */
main {
    padding: 2rem 0;
}

/* Footer */
footer {
    background-color: var(--header-bg);
    border-top: 1px solid var(--border-color);
    padding: 2rem 0;
    margin-top: 3rem;
    text-align: center;
    color: var(--text-muted);
}

footer p {
    margin: 0;
    font-size: 0.9rem;
}

/* Seções */
section {
    margin-bottom: 2rem;
    scroll-margin-top: 100px; /* Espaço para o header fixo ao fazer scroll */
}

section:last-child {
    margin-bottom: 0;
}

/* Geral */
* {
    box-sizing: border-box;
}

/* Responsividade */
@media (max-width: 768px) {
    .header-content {
        flex-direction: column;
        gap: 1rem;
    }
    
    nav ul {
        flex-wrap: wrap;
        justify-content: center;
    }
    
    .card {
        padding: 2rem;
    }
    
    h2 {
        font-size: 1.5rem;
    }
    
    .container {
        padding: 0 1.5rem;
    }
}