:root {
  --bg: #f4f6fb;
  --card: #ffffff;
  --text: #1d2433;
  --muted: #5d6679;
  --border: #dde2ec;
  --primary: #1f5fbf;
  --primary-text: #ffffff;
  --ok: #1a8a4a;
  --ok-bg: #e3f5ea;
  --err: #c0392b;
  --err-bg: #fbe7e5;
  --warn: #9a6700;
  --warn-bg: #fff4d6;
  --chip: #eef2fa;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #12161f;
    --card: #1b2130;
    --text: #e6e9f0;
    --muted: #9aa3b5;
    --border: #2c3446;
    --primary: #5b9bff;
    --primary-text: #0b1220;
    --ok: #4cd18a;
    --ok-bg: #16301f;
    --err: #ff7b6e;
    --err-bg: #3a1c1a;
    --warn: #f2c14e;
    --warn-bg: #332a12;
    --chip: #232b3d;
  }
}

* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.5;
  font-size: 16px;
}
a { color: var(--primary); }

.topo {
  position: sticky; top: 0; z-index: 10;
  display: flex; align-items: center; justify-content: space-between; gap: 12px;
  padding: 10px 16px;
  background: var(--card);
  border-bottom: 1px solid var(--border);
}
.topo .marca { font-weight: 700; text-decoration: none; color: var(--text); }
.topo nav a { margin-left: 14px; text-decoration: none; font-size: 14px; }

main { max-width: 860px; margin: 0 auto; padding: 16px; }
h1 { font-size: 1.5rem; margin: 8px 0 4px; }
h2 { font-size: 1.2rem; margin: 20px 0 8px; }
.sub { color: var(--muted); margin: 0 0 12px; }

.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 16px;
  margin-bottom: 12px;
}
.destaque { border-color: var(--primary); }

.contagem { display: flex; align-items: center; gap: 16px; }
.contagem .num { font-size: 2.4rem; font-weight: 800; color: var(--primary); line-height: 1; }

.grade { display: grid; grid-template-columns: repeat(auto-fill, minmax(180px, 1fr)); gap: 10px; }
.materia {
  display: block; text-decoration: none; color: var(--text);
  background: var(--card); border: 1px solid var(--border); border-radius: 12px; padding: 14px;
}
.materia:hover { border-color: var(--primary); }
.materia .ico { font-size: 1.6rem; }
.materia .nome { font-weight: 700; margin-top: 4px; }
.materia .info { color: var(--muted); font-size: 13px; }
.barra { height: 6px; background: var(--chip); border-radius: 4px; margin-top: 8px; overflow: hidden; }
.barra > span { display: block; height: 100%; background: var(--primary); }

.btn {
  display: inline-block; border: 1px solid var(--primary); background: var(--primary); color: var(--primary-text);
  padding: 10px 18px; border-radius: 10px; font-size: 15px; font-weight: 600; cursor: pointer; text-decoration: none;
}
.btn.sec { background: transparent; color: var(--primary); }
.btn:disabled { opacity: .45; cursor: default; }
.btn.grande { width: 100%; padding: 14px; font-size: 17px; }

.abas { display: flex; gap: 6px; margin: 12px 0; }
.abas a {
  flex: 1; text-align: center; padding: 10px; border-radius: 10px; text-decoration: none;
  border: 1px solid var(--border); background: var(--card); color: var(--text); font-weight: 600;
}
.abas a.ativa { background: var(--primary); color: var(--primary-text); border-color: var(--primary); }

.sims { display: grid; grid-template-columns: repeat(auto-fill, minmax(140px, 1fr)); gap: 10px; }
.sim {
  display: block; text-decoration: none; color: var(--text); text-align: center;
  background: var(--card); border: 1px solid var(--border); border-radius: 12px; padding: 14px 8px;
}
.sim:hover { border-color: var(--primary); }
.sim .t { font-weight: 700; }
.sim .s { font-size: 13px; color: var(--muted); }
.sim.feito { border-color: var(--ok); }
.sim.feito .s { color: var(--ok); font-weight: 600; }

/* Questão */
.progresso { display: flex; justify-content: space-between; color: var(--muted); font-size: 14px; margin-bottom: 6px; }
.tag { display: inline-block; background: var(--chip); color: var(--muted); border-radius: 6px; padding: 2px 8px; font-size: 12px; margin-right: 6px; }
.texto-apoio {
  background: var(--chip); border-left: 4px solid var(--primary); border-radius: 8px;
  padding: 12px 14px; margin: 10px 0; font-size: 15px;
}
.enunciado { font-size: 17px; margin: 10px 0 14px; }
.alt {
  display: flex; gap: 10px; align-items: flex-start; width: 100%; text-align: left;
  background: var(--card); color: var(--text); border: 2px solid var(--border); border-radius: 10px;
  padding: 12px; margin-bottom: 8px; font-size: 16px; cursor: pointer; font-family: inherit;
}
.alt:hover { border-color: var(--primary); }
.alt .letra {
  flex: 0 0 28px; height: 28px; border-radius: 50%; display: flex; align-items: center; justify-content: center;
  background: var(--chip); font-weight: 700;
}
.alt.sel { border-color: var(--primary); }
.alt.sel .letra { background: var(--primary); color: var(--primary-text); }
.alt.certa { border-color: var(--ok); background: var(--ok-bg); }
.alt.certa .letra { background: var(--ok); color: #fff; }
.alt.errada { border-color: var(--err); background: var(--err-bg); }
.alt.errada .letra { background: var(--err); color: #fff; }
.alt.fixa { cursor: default; }

.nav-q { display: flex; justify-content: space-between; gap: 10px; margin-top: 14px; }
.mapa { display: grid; grid-template-columns: repeat(auto-fill, minmax(38px, 1fr)); gap: 4px; margin-top: 16px; }
.mapa button {
  border: 1px solid var(--border); background: var(--card); color: var(--text); border-radius: 6px;
  padding: 6px 0; font-size: 13px; cursor: pointer;
}
.mapa button.resp { background: var(--chip); font-weight: 700; }
.mapa button.atual { border: 2px solid var(--primary); }

/* Resultado */
.placar { text-align: center; }
.placar .grande { font-size: 3rem; font-weight: 800; line-height: 1.1; }
.ok { color: var(--ok); }
.err { color: var(--err); }
.aviso { background: var(--warn-bg); color: var(--warn); border-radius: 10px; padding: 10px 14px; margin: 10px 0; }
.explica { background: var(--chip); border-radius: 8px; padding: 10px 12px; margin-top: 6px; font-size: 15px; }
.rev { border-left: 5px solid var(--border); }
.rev.acerto { border-left-color: var(--ok); }
.rev.erro { border-left-color: var(--err); }
.filtros { display: flex; gap: 6px; flex-wrap: wrap; margin: 10px 0; }
.filtros button {
  border: 1px solid var(--border); background: var(--card); color: var(--text); border-radius: 20px;
  padding: 6px 14px; cursor: pointer; font-size: 14px;
}
.filtros button.ativa { background: var(--primary); color: var(--primary-text); border-color: var(--primary); }

table { border-collapse: collapse; width: 100%; font-size: 15px; }
th, td { border-bottom: 1px solid var(--border); padding: 7px 8px; text-align: left; vertical-align: top; }
th { background: var(--chip); }
.tabela-wrap { overflow-x: auto; }

/* Conteúdo didático (gerado do markdown) */
.conteudo { overflow-wrap: anywhere; }
.conteudo h1 { font-size: 1.4rem; }
.conteudo h2 { border-bottom: 2px solid var(--border); padding-bottom: 4px; margin-top: 28px; }
.conteudo h3 { margin-top: 20px; }
.conteudo table { display: block; overflow-x: auto; margin: 10px 0; }
.conteudo blockquote { margin: 10px 0; padding: 8px 14px; border-left: 4px solid var(--primary); background: var(--chip); border-radius: 6px; }
.conteudo pre { background: var(--chip); padding: 10px; border-radius: 8px; overflow-x: auto; font-size: 14px; }
.conteudo code { background: var(--chip); padding: 1px 5px; border-radius: 4px; font-size: .9em; }
.conteudo pre code { background: none; padding: 0; }
.indice { columns: 2; font-size: 14px; }
@media (max-width: 560px) { .indice { columns: 1; } }

.rodape { color: var(--muted); font-size: 13px; text-align: center; margin: 30px 0 10px; }

.pend { display: inline-block; width: 1.2em; text-align: center; color: var(--muted); font-weight: 700; }
@media (max-width: 480px) {
  .topo { padding: 8px 12px; }
  .topo nav a { margin-left: 10px; font-size: 13px; }
}
.aluno { max-width: 860px; margin: 0 auto; padding: 8px 16px 0; font-size: 14px; color: var(--muted); }
.aluno:empty { display: none; }
.aluno #nuvem { margin-left: 8px; font-size: 13px; }