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

:root {
  --primary: #1a5276;
  --primary-light: #2e86c1;
  --primary-dark: #0e2f44;
  --accent: #d4ac0d;
  --success: #27ae60;
  --error: #e74c3c;
  --bg: #f0f4f8;
  --card-bg: #ffffff;
  --text: #2c3e50;
  --text-light: #7f8c8d;
  --border: #dce1e8;
  --shadow: 0 2px 8px rgba(0,0,0,0.08);
  --radius: 8px;
}

body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 20px;
}

header {
  background: linear-gradient(135deg, var(--primary-dark), var(--primary));
  color: #fff;
  padding: 15px 0;
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: 0 2px 10px rgba(0,0,0,0.2);
}

.header-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo {
  display: flex;
  align-items: center;
  gap: 12px;
  cursor: pointer;
}

.logo-icon {
  font-size: 28px;
}

.logo h1 {
  font-size: 22px;
  font-weight: 700;
  letter-spacing: 0.5px;
}

nav {
  display: flex;
  gap: 5px;
}

.nav-btn {
  background: transparent;
  color: rgba(255,255,255,0.8);
  border: 1px solid transparent;
  padding: 8px 16px;
  border-radius: 6px;
  cursor: pointer;
  font-size: 14px;
  font-weight: 500;
  transition: all 0.2s;
}

.nav-btn:hover {
  background: rgba(255,255,255,0.1);
  color: #fff;
}

.nav-btn.ativo {
  background: rgba(255,255,255,0.2);
  color: #fff;
  border-color: rgba(255,255,255,0.3);
}

.cronometro-badge {
  display: flex;
  align-items: center;
  gap: 6px;
  background: rgba(255,255,255,0.12);
  color: #fff;
  padding: 6px 14px;
  border-radius: 20px;
  font-size: 13px;
  font-weight: 600;
  font-variant-numeric: tabular-nums;
  white-space: nowrap;
}

.cronometro-icon {
  font-size: 14px;
}

main {
  flex: 1;
  padding: 30px 0;
}

.pagina {
  display: none;
}

.pagina.ativa {
  display: block;
}

.hero {
  text-align: center;
  padding: 50px 20px 40px;
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  color: #fff;
  border-radius: var(--radius);
  margin-bottom: 30px;
}

.hero h2 {
  font-size: 32px;
  margin-bottom: 12px;
}

.hero p {
  font-size: 17px;
  opacity: 0.9;
  max-width: 600px;
  margin: 0 auto;
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  margin-bottom: 30px;
}

.stat-card {
  background: var(--card-bg);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 24px;
  text-align: center;
}

.stat-num {
  font-size: 36px;
  font-weight: 700;
  color: var(--primary);
}

.stat-label {
  font-size: 13px;
  color: var(--text-light);
  margin-top: 4px;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.disciplinas-grid, .acoes-rapidas {
  margin-bottom: 30px;
}

.disciplinas-grid h3, .acoes-rapidas h3 {
  font-size: 18px;
  margin-bottom: 15px;
  color: var(--primary-dark);
}

.disciplinas-cards, .acoes-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
  gap: 12px;
}

.disciplina-card {
  background: var(--card-bg);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 16px;
  text-align: center;
  cursor: pointer;
  transition: all 0.2s;
  border: 2px solid transparent;
}

.disciplina-card:hover {
  border-color: var(--primary-light);
  transform: translateY(-2px);
}

.disciplina-card .disc-nome {
  font-weight: 600;
  font-size: 13px;
  color: var(--primary);
}

.disciplina-card .disc-qtd {
  font-size: 11px;
  color: var(--text-light);
  margin-top: 4px;
}

.disciplina-card .disc-tempo {
  font-size: 11px;
  color: var(--primary-light);
  margin-top: 2px;
}

.grafico-secao {
  margin-top: 30px;
}

.grafico-secao h3 {
  font-size: 18px;
  margin-bottom: 15px;
  color: var(--primary-dark);
}

.grafico-barras {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.barra-disciplina {
  background: var(--card-bg);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 14px 18px;
}

.barra-info {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  font-size: 13px;
  margin-bottom: 8px;
}

.barra-nome {
  font-weight: 600;
  color: var(--text);
}

.barra-valor {
  color: var(--text-light);
  white-space: nowrap;
}

.barra-trilho {
  background: #eef1f5;
  border-radius: 6px;
  height: 10px;
  overflow: hidden;
}

.barra-preenchida {
  height: 100%;
  border-radius: 6px;
  background: var(--primary-light);
  transition: width 0.3s;
}

.barra-preenchida.forte {
  background: var(--success);
}

.barra-preenchida.media {
  background: var(--accent);
}

.barra-preenchida.fraca {
  background: var(--error);
}

.barra-tempo {
  font-size: 11px;
  color: var(--text-light);
  margin-top: 6px;
}

.acao-card {
  background: var(--card-bg);
  border: 2px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 20px;
  text-align: center;
  cursor: pointer;
  transition: all 0.2s;
  font-size: 14px;
  font-weight: 500;
  color: var(--text);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
}

.acao-card:hover {
  border-color: var(--primary-light);
  transform: translateY(-2px);
}

.acao-icon {
  font-size: 24px;
}

.page-header {
  margin-bottom: 24px;
}

.page-header h2 {
  font-size: 24px;
  color: var(--primary-dark);
  margin-bottom: 6px;
}

.subtitulo {
  color: var(--text-light);
  font-size: 14px;
}

.filtros {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
  margin-top: 15px;
}

.filtros select {
  padding: 9px 14px;
  border: 1px solid var(--border);
  border-radius: 6px;
  background: #fff;
  font-size: 13px;
  color: var(--text);
  cursor: pointer;
  min-width: 180px;
}

.filtros select:focus {
  outline: none;
  border-color: var(--primary-light);
}

.btn-secondary {
  padding: 9px 18px;
  background: var(--accent);
  color: #fff;
  border: none;
  border-radius: 6px;
  cursor: pointer;
  font-size: 13px;
  font-weight: 600;
  transition: background 0.2s;
}

.btn-secondary:hover {
  background: #b8940a;
}

.questoes-lista {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.questao-card {
  background: var(--card-bg);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 24px;
  border-left: 4px solid var(--primary-light);
}

.questao-meta {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  margin-bottom: 14px;
}

.tag {
  display: inline-block;
  padding: 3px 10px;
  border-radius: 12px;
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.3px;
}

.tag-exame {
  background: var(--primary);
  color: #fff;
}

.tag-disciplina {
  background: #eaf2f8;
  color: var(--primary);
}

.tag-status {
  background: #f0f0f0;
  color: var(--text-light);
}

.tag-correta {
  background: #d5f5e3;
  color: #1e8449;
}

.tag-errada {
  background: #fadbd8;
  color: #922b21;
}

.questao-enunciado {
  font-size: 15px;
  line-height: 1.7;
  margin-bottom: 16px;
}

.alternativas {
  display: flex;
  flex-direction: column;
  gap: 8px;
  margin-bottom: 16px;
}

.alternativa {
  padding: 11px 14px;
  border: 2px solid var(--border);
  border-radius: 6px;
  cursor: pointer;
  transition: all 0.2s;
  font-size: 14px;
  line-height: 1.5;
}

.alternativa:hover {
  border-color: var(--primary-light);
  background: #f7f9fc;
}

.alternativa.selecionada {
  border-color: var(--primary);
  background: #ebf5fb;
  font-weight: 500;
}

.alternativa.correta {
  border-color: var(--success);
  background: #d5f5e3;
  font-weight: 500;
}

.alternativa.errada {
  border-color: var(--error);
  background: #fadbd8;
  font-weight: 500;
}

.gabarito-box {
  margin-top: 16px;
  padding: 16px;
  background: #f8f9fa;
  border-radius: 6px;
  border: 1px solid var(--border);
}

.gabarito-box .resposta {
  font-weight: 600;
  font-size: 14px;
  margin-bottom: 8px;
}

.gabarito-box .resposta.certa {
  color: var(--success);
}

.gabarito-box .resposta.errada {
  color: var(--error);
}

.gabarito-box .explicacao {
  font-size: 14px;
  color: var(--text);
  line-height: 1.6;
}

.comentario-area {
  margin-top: 14px;
  border-top: 1px solid var(--border);
  padding-top: 14px;
}

.comentario-area textarea {
  width: 100%;
  min-height: 70px;
  padding: 10px;
  border: 1px solid var(--border);
  border-radius: 6px;
  font-size: 13px;
  font-family: inherit;
  resize: vertical;
}

.comentario-area textarea:focus {
  outline: none;
  border-color: var(--primary-light);
}

.comentario-area .comentario-salvo {
  font-size: 12px;
  color: var(--success);
  margin-top: 4px;
  display: none;
}

.comentario-area .btn-salvar {
  margin-top: 6px;
  padding: 6px 16px;
  background: var(--primary);
  color: #fff;
  border: none;
  border-radius: 4px;
  cursor: pointer;
  font-size: 12px;
}

.paginacao {
  display: flex;
  justify-content: center;
  gap: 6px;
  margin-top: 24px;
  flex-wrap: wrap;
}

.paginacao button {
  padding: 7px 13px;
  border: 1px solid var(--border);
  border-radius: 4px;
  background: #fff;
  cursor: pointer;
  font-size: 13px;
  transition: all 0.2s;
}

.paginacao button:hover {
  background: var(--bg);
}

.paginacao button.ativo {
  background: var(--primary);
  color: #fff;
  border-color: var(--primary);
}

#comentarios-container {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.comentario-card {
  background: var(--card-bg);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 20px;
  border-left: 4px solid var(--accent);
}

.comentario-card .ref-questao {
  font-size: 12px;
  color: var(--text-light);
  margin-bottom: 6px;
}

.comentario-card .ref-questao strong {
  color: var(--text);
}

.comentario-card .comentario-texto {
  font-size: 14px;
  line-height: 1.6;
  color: var(--text);
  white-space: pre-wrap;
}

.comentario-card .btn-ver-questao {
  margin-top: 10px;
  padding: 5px 12px;
  background: transparent;
  border: 1px solid var(--primary-light);
  color: var(--primary);
  border-radius: 4px;
  cursor: pointer;
  font-size: 12px;
}

.download-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 16px;
}

.download-card {
  background: var(--card-bg);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 20px;
  border: 1px solid var(--border);
}

.download-card h4 {
  font-size: 16px;
  color: var(--primary-dark);
  margin-bottom: 6px;
}

.download-card .download-info {
  font-size: 13px;
  color: var(--text-light);
  margin-bottom: 12px;
}

.download-links {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.download-card .btn-download {
  display: inline-block;
  padding: 8px 20px;
  background: var(--primary);
  color: #fff;
  border: none;
  border-radius: 6px;
  cursor: pointer;
  font-size: 13px;
  font-weight: 500;
  transition: background 0.2s;
  text-decoration: none;
  text-align: center;
}

.download-card .btn-download:hover {
  background: var(--primary-dark);
}

.download-card .btn-download-gabarito {
  background: var(--success);
}

.download-card .btn-download-gabarito:hover {
  background: #1e8449;
}

.download-card .btn-download.disabled {
  background: #ccc;
  color: #888;
  cursor: not-allowed;
}

.sem-questoes {
  text-align: center;
  padding: 60px 20px;
  color: var(--text-light);
}

.sem-questoes p {
  font-size: 16px;
}

footer {
  background: var(--primary-dark);
  color: rgba(255,255,255,0.7);
  padding: 20px 0;
  text-align: center;
  font-size: 13px;
  margin-top: 30px;
}

@media (max-width: 768px) {
  .header-container {
    flex-direction: column;
    gap: 12px;
  }

  .barra-info {
    flex-direction: column;
    gap: 2px;
  }

  .hero h2 {
    font-size: 24px;
  }

  .hero p {
    font-size: 15px;
  }

  .stats-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .filtros {
    flex-direction: column;
  }

  .filtros select {
    width: 100%;
  }

  nav {
    flex-wrap: wrap;
    justify-content: center;
  }

  .nav-btn {
    font-size: 12px;
    padding: 6px 10px;
  }
}

@media (max-width: 480px) {
  .stats-grid {
    grid-template-columns: 1fr;
  }

  .disciplinas-cards {
    grid-template-columns: repeat(2, 1fr);
  }

  .questao-card {
    padding: 16px;
  }
}