:root {
  --brand-red: #EA0633;
  --brand-red-dark: #B8042A;
  --brand-red-tint: #FCE4E9;
  --brand-black: #14161B;
  --brand-black-soft: #1C1F26;
  --brand-blue: #1E4FE0;
  --brand-blue-dark: #15379E;
  --brand-blue-tint: #E8EDFC;
  --portal-link: #5B8DFF;   /* azul mais vivo/alinhado à marca pra texto sobre fundo escuro do portal (o antigo #7CA0FF ficava lavado) */
  --surface: #ffffff;
  --surface-alt: #f5f6f8;
  --border: #e2e5ec;
  --text: #1f2430;
  --text-muted: #6b7280;
}

* { box-sizing: border-box; }
body {
  font-family: -apple-system, "Segoe UI", Roboto, Arial, sans-serif;
  margin: 0;
  background: var(--surface-alt);
  color: var(--text);
}
header.topbar {
  background: var(--brand-black);
  color: #fff;
  padding: 10px 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-bottom: 3px solid var(--brand-red);
}
header.topbar a { color: #fff; text-decoration: none; }
header.topbar .brand { font-weight: 600; font-size: 18px; display: flex; align-items: center; gap: 10px; }
header.topbar .brand img { height: 30px; width: auto; display: block; }
header.topbar .userbox { display: flex; align-items: center; gap: 10px; font-size: 14px; }
header.topbar .avatar-sm { width: 28px; height: 28px; border-radius: 50%; object-fit: cover; border: 2px solid var(--brand-red); display: block; }
header.topbar .avatar-placeholder { width: 28px; height: 28px; border-radius: 50%; background: var(--brand-black-soft); border: 2px solid var(--brand-blue); display: flex; align-items: center; justify-content: center; font-size: 12px; color: #cfd6e6; }
nav.tabs {
  background: var(--brand-black-soft);
  padding: 0 24px;
  display: flex;
  gap: 4px;
  flex-wrap: wrap;
}
nav.tabs a {
  color: #cfd6e6;
  text-decoration: none;
  padding: 10px 14px;
  font-size: 14px;
}
nav.tabs a:hover, nav.tabs a.active { background: var(--brand-red); color: #fff; }
main { padding: 24px; max-width: 1100px; margin: 0 auto; }
.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 20px;
  margin-bottom: 20px;
}
h1 { font-size: 22px; margin: 0 0 16px; }
h2 { font-size: 17px; margin: 0 0 12px; }
table { width: 100%; border-collapse: collapse; font-size: 14px; }
th, td { text-align: left; padding: 8px 10px; border-bottom: 1px solid #eceef2; }
th { color: var(--text-muted); font-weight: 500; font-size: 12px; text-transform: uppercase; }
form.inline { display: flex; gap: 8px; flex-wrap: wrap; align-items: flex-end; margin-bottom: 16px; }
label { display: block; font-size: 12px; color: var(--text-muted); margin-bottom: 4px; }
input, select, textarea {
  padding: 7px 9px;
  border: 1px solid #d1d5db;
  border-radius: 6px;
  font-size: 14px;
  font-family: inherit;
}
input:focus, select:focus, textarea:focus {
  outline: none;
  border-color: var(--brand-blue);
  box-shadow: 0 0 0 3px var(--brand-blue-tint);
}
button, .btn {
  background: var(--brand-red);
  color: #fff;
  border: none;
  border-radius: 6px;
  padding: 8px 14px;
  font-size: 14px;
  cursor: pointer;
  text-decoration: none;
  display: inline-block;
}
button:hover, .btn:hover { background: var(--brand-red-dark); }
button.secondary, .btn.secondary { background: var(--brand-blue-tint); color: var(--brand-blue-dark); }
button.secondary:hover, .btn.secondary:hover { background: #d7e0fa; }
button.danger, .btn.danger { background: var(--brand-black); }
button.danger:hover, .btn.danger:hover { background: #000; }
.badge { padding: 2px 8px; border-radius: 12px; font-size: 12px; }
.badge.ok { background: #dcfce7; color: #166534; }
.badge.warn { background: #fef9c3; color: #854d0e; }
.badge.risk { background: var(--brand-red-tint); color: var(--brand-red-dark); }
.badge.muted { background: #e5e7eb; color: #374151; }
.badge.info { background: var(--brand-blue-tint); color: var(--brand-blue-dark); }
.grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 16px; }
.stat { font-size: 28px; font-weight: 600; }
.stat-label { font-size: 12px; color: var(--text-muted); }
.locked { color: #9ca3af; font-style: italic; }
.flash { background: var(--brand-blue-tint); color: var(--brand-blue-dark); padding: 10px 14px; border-radius: 6px; margin-bottom: 16px; font-size: 14px; }
.flash.erro { background: var(--brand-red-tint); color: var(--brand-red-dark); }
.login-wrap { display: flex; align-items: center; justify-content: center; min-height: 80vh; }
.login-box { background: #fff; padding: 32px; border-radius: 10px; width: 320px; border: 1px solid var(--border); border-top: 4px solid var(--brand-red); text-align: center; }
.login-box .login-logo { height: 64px; width: auto; margin-bottom: 16px; }
.login-box h1 { text-align: center; }
.login-box form { text-align: left; }
.avatar-lg { width: 96px; height: 96px; border-radius: 50%; object-fit: cover; border: 3px solid var(--brand-red); display: block; }
.avatar-lg-placeholder { width: 96px; height: 96px; border-radius: 50%; background: var(--brand-black-soft); border: 3px solid var(--brand-blue); display: flex; align-items: center; justify-content: center; font-size: 28px; color: #cfd6e6; font-weight: 600; }

.subtabs { display: flex; gap: 6px; flex-wrap: wrap; margin-bottom: 18px; border-bottom: 1px solid var(--border); padding-bottom: 12px; }
.subtabs button, .subtabs a { background: #eef0f4; color: #374151; border: none; border-radius: 6px; padding: 8px 14px; font-size: 13px; cursor: pointer; display: inline-block; }
.subtabs button.active, .subtabs a.active { background: var(--brand-black); color: #fff; }
.subtabs button .tab-warn { color: var(--brand-red-dark); margin-left: 4px; }
.tab-panel[hidden] { display: none; }
.dropdown { position: relative; display: inline-block; }
.dropdown-menu { display: none; position: absolute; top: 100%; left: 0; background: var(--brand-black-soft); border: 1px solid rgba(255,255,255,0.1); border-radius: 6px; box-shadow: 0 4px 12px rgba(0,0,0,0.25); min-width: 220px; z-index: 10; margin-top: 4px; }
.dropdown-menu a { display: block; padding: 9px 14px; font-size: 13px; color: #cfd6e6; text-decoration: none; }
.dropdown-menu a:hover { background: var(--brand-red); color: #fff; }
.dropdown.open .dropdown-menu { display: block; }

.navdrop { position: relative; display: inline-block; }
.navdrop > a { color: #cfd6e6; text-decoration: none; padding: 10px 14px; font-size: 14px; display: inline-block; }
.navdrop > a:hover, .navdrop > a.active { background: var(--brand-red); color: #fff; }
.navdrop-menu { display: none; position: absolute; top: 100%; left: 0; background: var(--brand-black-soft); border: 1px solid rgba(255,255,255,0.1); border-radius: 6px; box-shadow: 0 4px 12px rgba(0,0,0,0.25); min-width: 160px; z-index: 20; margin-top: 2px; }
.navdrop-menu a { display: block; padding: 10px 14px; font-size: 13px; color: #cfd6e6; text-decoration: none; }
.navdrop-menu a:hover { background: var(--brand-red); color: #fff; }
.navdrop.open .navdrop-menu { display: block; }

/* ---------- Portal do aluno: tema "tech", mais escuro e com fonte monoespaçada nos títulos ---------- */
body.portal {
  background-color: var(--brand-black);
  background-image:
    linear-gradient(rgba(234,6,51,0.06) 1px, transparent 1px),
    linear-gradient(90deg, rgba(30,79,224,0.08) 1px, transparent 1px);
  background-size: 34px 34px;
  color: #E7E9EE;
  min-height: 100vh;
}
body.portal header.topbar {
  background: rgba(20,22,27,0.92);
  border-bottom: 3px solid var(--brand-red);
}
body.portal h1, body.portal h2 {
  font-family: Consolas, "Cascadia Code", "SFMono-Regular", "Courier New", monospace;
  letter-spacing: 0.3px;
}
body.portal h1 { color: #fff; }
body.portal h1::before { content: "> "; color: var(--portal-link); }
body.portal h2 { color: var(--brand-red); text-transform: uppercase; font-size: 14px; letter-spacing: 1px; }
body.portal .card {
  background: rgba(28,31,38,0.92);
  border: 1px solid rgba(255,255,255,0.08);
  border-left: 3px solid var(--brand-blue);
  color: #E7E9EE;
}
body.portal table { color: #E7E9EE; }
body.portal th { color: #8891a3; border-bottom-color: rgba(255,255,255,0.08); }
body.portal td { border-bottom-color: rgba(255,255,255,0.08); }
body.portal a { color: var(--portal-link); }
body.portal .locked { color: #6b7280; }
body.portal label { color: #9aa3b5; }
body.portal input, body.portal select, body.portal textarea {
  background: #0f1115; color: #E7E9EE; border-color: rgba(255,255,255,0.15);
}
body.portal .login-box { background: rgba(28,31,38,0.95); border-color: rgba(255,255,255,0.1); color: #E7E9EE; }
body.portal .flash { background: rgba(30,79,224,0.18); color: #BBD0FF; }
body.portal .stat-label { color: #8891a3; }

/* ---------- Exercício de fim de aula: fonte maior (mais fácil de ler durante a aula) e imagem por questão ---------- */
.questao-bloco { margin-bottom: 24px; }
.questao-enunciado { display: block; font-size: 19px; font-weight: 600; margin-bottom: 10px; line-height: 1.4; }
.questao-imagem { display: block; max-width: 100%; max-height: 340px; border-radius: 8px; margin-bottom: 12px; }
.questao-opcao-linha { display: flex; align-items: center; gap: 10px; margin: 8px 0; }
.questao-opcao { margin: 0; font-weight: normal; font-size: 17px; }
.questao-opcao-revisao { padding: 6px 10px; border-radius: 6px; }
.questao-opcao-revisao.questao-correta { background: rgba(34,197,94,0.15); }
.questao-opcao-revisao.questao-errada { background: rgba(234,6,51,0.12); }
body.portal .questao-opcao-revisao.questao-correta { background: rgba(34,197,94,0.18); }
body.portal .questao-opcao-revisao.questao-errada { background: rgba(234,6,51,0.2); }