/* ================================================
   VARIÁVEIS GLOBAIS
   ================================================ */
:root {
    --primary-color: #4a90e2;
    --success-color: #28a745;
    --danger-color: #dc3545;
    --warning-color: #ffc107;
    --info-color: #17a2b8;
    --dark-color: #2c3e50;
    --light-bg: #f8f9fa;
    --card-bg: #ffffff;
    --text-color: #212529;
    --text-secondary: #495057;
    --text-muted: #6c757d;
    --border-color: #dee2e6;
    --radius: 12px;
    --shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 25px rgba(0, 0, 0, 0.15);
    --element-bg: #f0f0f0;
    --header-gradient-start: #4a90e2;
    --header-gradient-end: #17a2b8;
    --badge-bg-opacity: 0.2;
    --hover-bg: #e9ecef;
}

/* ================================================
   MODO ESCURO - VARIÁVEIS
   ================================================ */
body.dark-mode {
    --light-bg: #0d1117;
    --card-bg: #161b22;
    --text-color: #e6edf3;
    --text-secondary: #c9d1d9;
    --text-muted: #8b949e;
    --border-color: #30363d;
    --dark-color: #e6edf3;
    --element-bg: #1c2128;
    --header-gradient-start: #1a5490;
    --header-gradient-end: #0d4758;
    --badge-bg-opacity: 0.3;
    --hover-bg: #262c36;
    --primary-color: #58a6ff;
    --success-color: #3fb950;
    --danger-color: #f85149;
    --warning-color: #d29922;
    --info-color: #58a6ff;
    --shadow: 0 4px 6px rgba(0, 0, 0, 0.3);
    --shadow-lg: 0 10px 25px rgba(0, 0, 0, 0.5);
}

/* ================================================
   ESTILOS BASE
   ================================================ */
body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: var(--light-bg);
    color: var(--text-color);
    transition: all 0.3s ease;
}

body.dark-mode {
    background-color: #0d1117 !important;
    color: #e6edf3 !important;
}

h1, h2, h3, h4, h5, h6 {
    color: var(--text-color);
    font-weight: 600;
}

p, span, div {
    color: var(--text-color);
}

.text-muted {
    color: var(--text-muted) !important;
    opacity: 1;
}

small {
    color: var(--text-secondary);
}

/* ================================================
   BOTÃO MODO ESCURO
   ================================================ */
#dark-mode-toggle {
    background-color: var(--element-bg) !important;
    color: var(--text-color) !important;
    border: 1px solid var(--border-color) !important;
    border-radius: 50%;
    width: 48px;
    height: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: transform 0.4s ease, background-color 0.3s ease;
}

#dark-mode-toggle:hover {
    background-color: var(--hover-bg) !important;
    transform: rotate(180deg);
}

/* ================================================
   TELA DE BOAS-VINDAS
   ================================================ */
.welcome-container {
    min-height: 80vh;
    display: flex;
    align-items: center;
    justify-content: center;
}

.welcome-card {
    background: var(--card-bg);
    border-radius: var(--radius);
    padding: 3rem;
    text-align: center;
    box-shadow: var(--shadow-lg);
    max-width: 600px;
    width: 100%;
}

.dark-mode .welcome-card {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
}

.welcome-icon {
    font-size: 5rem;
    color: var(--primary-color);
    margin-bottom: 1.5rem;
}

.welcome-title {
    font-size: 2.5rem;
    font-weight: bold;
    color: var(--primary-color);
    margin-bottom: 0.5rem;
}

.welcome-subtitle {
    color: var(--text-color);
    margin-bottom: 1.5rem;
    font-weight: 500;
}

.welcome-description {
    font-size: 1.1rem;
    color: var(--text-color);
    margin-bottom: 2rem;
}

.welcome-feature {
    background: linear-gradient(135deg, var(--primary-color), var(--info-color));
    color: white;
    padding: 1.5rem;
    border-radius: var(--radius);
    margin-bottom: 2rem;
    display: flex;
    align-items: center;
    gap: 1rem;
}

.dark-mode .welcome-feature {
    background: linear-gradient(135deg, var(--header-gradient-start), var(--header-gradient-end));
    color: #ffffff;
}

.welcome-feature i {
    font-size: 2rem;
    color: #ffffff;
}

.dark-mode .welcome-feature i {
    color: #ffc107;
}

.welcome-feature-text {
    font-size: 1rem;
    line-height: 1.5;
    text-align: left;
    color: #ffffff !important;
}

/* ================================================
   BOTÕES MODERNOS
   ================================================ */
.btn-modern {
    padding: 0.75rem 2rem;
    border-radius: var(--radius);
    border: none;
    font-weight: 600;
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: var(--shadow);
    display: inline-flex;
    align-items: center;
    justify-content: center;
}

.dark-mode .btn-modern {
    box-shadow: var(--shadow);
}

.btn-modern-primary {
    background: linear-gradient(135deg, var(--primary-color), #357abd);
    color: white;
}

.btn-modern-primary:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
    color: white;
}

.btn-modern-secondary {
    background: #6c757d;
    color: white;
}

.btn-modern-secondary:hover {
    background: #5a6268;
    transform: translateY(-2px);
    color: white;
}

.btn-modern-success {
    background: var(--success-color);
    color: white;
}

.btn-modern-success:hover {
    background: #218838;
    transform: translateY(-2px);
    color: white;
}

.btn-modern-danger {
    background: var(--danger-color);
    color: white;
}

.btn-modern-danger:hover {
    background: #c82333;
    transform: translateY(-2px);
    color: white;
}

/* ================================================
   HEADER MODERNO
   ================================================ */
.header-modern {
    background: var(--card-bg);
    padding: 1.5rem;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.dark-mode .header-modern {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
}

.header-modern-content {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.header-modern-content i {
    font-size: 2.5rem;
    color: var(--primary-color);
}

.header-modern h2 {
    margin: 0;
    color: var(--text-color);
    font-weight: 600;
}

.header-modern p {
    margin: 0;
    color: var(--text-secondary);
    font-size: 0.95rem;
}

/* ================================================
   CARDS DE ÁREA
   ================================================ */
.area-card {
    background: var(--card-bg);
    border-radius: var(--radius);
    margin-bottom: 2rem;
    box-shadow: var(--shadow);
    overflow: hidden;
}

.dark-mode .area-card {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
}

.area-card .card-header {
    background: linear-gradient(135deg, var(--primary-color), var(--info-color));
    color: white;
    padding: 1.25rem;
    border: none;
}

.dark-mode .area-card .card-header {
    background: linear-gradient(135deg, var(--header-gradient-start), var(--header-gradient-end));
    border-bottom: 1px solid var(--border-color);
}

.area-card .card-header h4 {
    margin: 0;
    font-weight: 600;
    color: #ffffff;
}

.area-card .card-body {
    padding: 0;
}

/* ================================================
   ITENS DE MATÉRIA
   ================================================ */
.materia-item {
    padding: 1.25rem;
    border-bottom: 1px solid var(--border-color);
    cursor: pointer;
    transition: all 0.3s ease;
}

.dark-mode .materia-item {
    border-bottom: 1px solid var(--border-color);
}

.materia-item:last-child {
    border-bottom: none;
}

.materia-item:hover {
    background: var(--light-bg);
    transform: translateX(5px);
}

.dark-mode .materia-item:hover {
    background: var(--element-bg);
}

.materia-item h6 {
    margin: 0 0 0.5rem 0;
    color: var(--text-color);
    font-weight: 600;
}

.materia-item h6 small {
    color: var(--text-secondary);
    font-weight: 400;
}

.materia-item p {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.materia-completa {
    background: rgba(40, 167, 69, 0.05);
}

.dark-mode .materia-completa {
    background: rgba(63, 185, 80, var(--badge-bg-opacity));
}

.materia-em-andamento {
    background: rgba(255, 193, 7, 0.05);
}

.dark-mode .materia-em-andamento {
    background: rgba(210, 153, 34, var(--badge-bg-opacity));
}

/* ================================================
   ESTATÍSTICAS
   ================================================ */
.stats-footer {
    background: var(--card-bg);
    border-radius: var(--radius);
    padding: 2rem;
    box-shadow: var(--shadow);
}

.dark-mode .stats-footer {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.stat-card {
    background: var(--light-bg);
    border-radius: var(--radius);
    padding: 1.5rem;
    display: flex;
    align-items: center;
    gap: 1rem;
}

.dark-mode .stat-card {
    background: var(--element-bg);
    border: 1px solid var(--border-color);
}

.stat-icon {
    width: 60px;
    height: 60px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    color: white;
}

.stat-icon-info {
    background: var(--info-color);
}

.stat-icon-success {
    background: var(--success-color);
}

.stat-icon-danger {
    background: var(--danger-color);
}

.stat-content h5 {
    margin: 0;
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--text-color);
}

.stat-content p {
    margin: 0;
    color: var(--text-secondary);
    font-size: 0.9rem;
}

/* ================================================
   PROGRESSO
   ================================================ */
.progress-section {
    margin-bottom: 1.5rem;
}

.progress-header {
    display: flex;
    justify-content: space-between;
    margin-bottom: 0.5rem;
}

.progress-label {
    font-weight: 600;
    color: var(--text-color);
}

.progress-value {
    color: var(--primary-color);
    font-weight: 600;
}

.progress-modern {
    background: var(--light-bg);
    border-radius: 50px;
    height: 30px;
    overflow: hidden;
    position: relative;
}

.dark-mode .progress-modern {
    background: var(--element-bg);
    border: 1px solid var(--border-color);
}

.progress-modern-bar {
    height: 100%;
    background: linear-gradient(90deg, var(--primary-color), var(--info-color));
    border-radius: 50px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-weight: 600;
    font-size: 0.85rem;
    transition: width 0.5s ease;
}

.dark-mode .progress-modern-bar {
    background: linear-gradient(90deg, var(--primary-color), var(--info-color));
}

.progress-modern-success {
    background: linear-gradient(90deg, var(--success-color), #20c997);
}

.progress-subtitle {
    display: block;
    margin-top: 0.5rem;
    color: var(--text-secondary);
}

/* ================================================
   TELA DE QUESTÕES
   ================================================ */
.question-header-card {
    background: var(--card-bg);
    border-radius: var(--radius);
    padding: 1.5rem;
    margin-bottom: 1.5rem;
    box-shadow: var(--shadow);
}

.dark-mode .question-header-card {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
}

.materia-nome {
    color: var(--text-color);
    font-weight: 600;
    margin: 0;
}

.materia-descricao {
    color: var(--text-secondary);
}

.question-counter {
    text-align: center;
    margin-top: 0.75rem;
    margin-bottom: 0;
    color: var(--text-color);
    font-weight: 600;
}

.question-card {
    background: var(--card-bg);
    border-radius: var(--radius);
    padding: 2rem;
    box-shadow: var(--shadow);
}

.dark-mode .question-card {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
}

.question-metadata {
    background: var(--light-bg);
    padding: 1rem;
    border-radius: var(--radius);
    margin-bottom: 1.5rem;
    color: var(--text-color);
    font-size: 0.9rem;
}

.dark-mode .question-metadata {
    background: var(--element-bg);
    border: 1px solid var(--border-color);
}

.question-image {
    max-width: 100%;
    border-radius: var(--radius);
    margin-bottom: 1.5rem;
    box-shadow: var(--shadow);
}

.question-title {
    color: var(--text-color);
    font-weight: 600;
    margin-bottom: 1.5rem;
    line-height: 1.6;
}

/* ================================================
   OPÇÕES DE RESPOSTA
   ================================================ */
.options-grid {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    margin-bottom: 2rem;
}

.quiz-option {
    background: var(--light-bg);
    border: 2px solid var(--border-color);
    border-radius: var(--radius);
    padding: 1rem;
    cursor: pointer;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
}

.dark-mode .quiz-option {
    background: var(--element-bg);
    border: 2px solid var(--border-color);
}

.quiz-option:hover {
    border-color: var(--primary-color);
    background: var(--card-bg);
    transform: translateX(5px);
}

.dark-mode .quiz-option:hover {
    border-color: var(--primary-color);
    background: var(--hover-bg);
}

.quiz-option input[type="radio"] {
    margin-right: 1rem;
    cursor: pointer;
}

.quiz-option label {
    cursor: pointer;
    margin: 0;
    width: 100%;
    color: var(--text-color);
}

.quiz-option input[type="radio"]:checked + label {
    font-weight: 600;
    color: var(--primary-color);
}

.dark-mode .quiz-option input[type="radio"]:checked + label {
    color: var(--primary-color);
}

/* ================================================
   AÇÕES DAS QUESTÕES
   ================================================ */
.question-actions {
    display: flex;
    gap: 1rem;
    justify-content: center;
}

/* ================================================
   MODAL DE CONTEXTO
   ================================================ */
.context-modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.7);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 9999;
    opacity: 0;
    transition: opacity 0.3s ease;
}

.context-modal-overlay.show {
    opacity: 1;
}

.context-modal-content {
    background: var(--card-bg);
    border-radius: var(--radius);
    padding: 2rem;
    max-width: 700px;
    width: 90%;
    max-height: 80vh;
    overflow-y: auto;
    position: relative;
    box-shadow: var(--shadow-lg);
    color: var(--text-color);
}

.dark-mode .context-modal-content {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    color: var(--text-color);
}

.modal-close-btn {
    position: absolute;
    top: 1rem;
    right: 1rem;
    background: var(--danger-color);
    color: white;
    border: none;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    font-size: 1.5rem;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.3s ease;
}

.modal-close-btn:hover {
    background: #c82333;
    transform: rotate(90deg);
}

/* ================================================
   BADGES & ALERTS
   ================================================ */
.badge {
    font-weight: 500;
}

.dark-mode .badge-secondary {
    background-color: #6c757d;
    color: #fff;
}

.dark-mode .badge-success {
    background-color: var(--success-color);
}

.dark-mode .badge-danger {
    background-color: var(--danger-color);
}

.dark-mode .badge-warning {
    background-color: var(--warning-color);
    color: #000;
}

.dark-mode .badge-primary {
    background-color: var(--primary-color);
}

.dark-mode .card.border-success {
    border-color: var(--success-color) !important;
    background-color: rgba(63, 185, 80, 0.05);
}

.dark-mode .card.border-danger {
    border-color: var(--danger-color) !important;
    background-color: rgba(248, 81, 73, 0.05);
}

/* ================================================
   ANIMAÇÃO E DISPLAY
   ================================================ */
.fade-in {
    animation: fadeIn 0.5s ease;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.d-none {
    display: none !important;
}

@media (max-width: 768px) {
    .welcome-card { padding: 2rem 1.5rem; }
    .welcome-title { font-size: 2rem; }
    .stats-grid { grid-template-columns: 1fr; }
    .header-modern { flex-direction: column; gap: 1rem; }
    .question-actions { flex-direction: column; }
    .btn-modern { width: 100%; }
}