:root {
  --bg: #0f1420;
  --panel: #18202f;
  --panel2: #1f2939;
  --text: #e8edf5;
  --muted: #9aa7bd;
  --accent: #4f8cff;
  --ok: #34c77b;
  --ko: #e5534b;
  --warn: #e0a83c;
  --border: #2a3648;
}
* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: 'Segoe UI', system-ui, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.55;
}
.topbar {
  display: flex; align-items: center; justify-content: space-between;
  padding: 12px 24px; background: var(--panel); border-bottom: 1px solid var(--border);
  position: sticky; top: 0; z-index: 10;
}
.brand { display: flex; gap: 12px; align-items: center; cursor: pointer; }
.brand small { display: block; color: var(--muted); }
.logo {
  background: var(--accent); color: #fff; font-weight: 700;
  width: 42px; height: 42px; border-radius: 10px;
  display: inline-flex; align-items: center; justify-content: center;
}
.progress-pill {
  background: var(--panel2); border: 1px solid var(--border);
  padding: 6px 14px; border-radius: 999px; font-size: .9em; color: var(--muted);
}
main { max-width: 980px; margin: 0 auto; padding: 24px; }
.hero h1 { margin-bottom: 4px; }
.hero p { color: var(--muted); margin-top: 0; }
.ut-heading { margin: 32px 0 12px; color: var(--accent); font-size: 1.1em; text-transform: uppercase; letter-spacing: .04em; }
.cards { display: grid; gap: 12px; grid-template-columns: repeat(auto-fill, minmax(290px, 1fr)); }
.ut-heading { grid-column: 1 / -1; }
.card {
  background: var(--panel); border: 1px solid var(--border); border-radius: 12px;
  padding: 16px; text-decoration: none; color: inherit; display: block;
  transition: transform .1s, border-color .1s;
}
.card:hover { transform: translateY(-2px); border-color: var(--accent); }
.card h3 { margin: 8px 0 6px; font-size: 1.02em; }
.card p { margin: 0 0 8px; color: var(--muted); font-size: .92em; }
.card small { color: var(--muted); }
.card-top { display: flex; justify-content: space-between; align-items: center; }
.card.completed { border-color: var(--ok); }
.done-badge { color: var(--ok); font-size: .85em; font-weight: 600; }
.ut-badge {
  background: var(--panel2); border: 1px solid var(--border); border-radius: 6px;
  padding: 2px 8px; font-size: .78em; color: var(--accent); font-weight: 600;
}
.breadcrumb { margin-bottom: 16px; display: flex; gap: 12px; align-items: center; color: var(--muted); }
.link { background: none; border: none; color: var(--accent); cursor: pointer; font-size: 1em; padding: 0; }
.session-head h1 { margin: 8px 0 4px; }
.intro { color: var(--muted); font-size: 1.05em; }
.content h2 { margin-top: 28px; color: var(--accent); font-size: 1.2em; }
.content h3 { color: var(--text); }
.content table { border-collapse: collapse; width: 100%; margin: 12px 0; font-size: .94em; }
.content th, .content td { border: 1px solid var(--border); padding: 7px 10px; text-align: left; vertical-align: top; }
.content th { background: var(--panel2); }
.content pre {
  background: #0b0f18; border: 1px solid var(--border); border-radius: 8px;
  padding: 14px; overflow-x: auto; font-size: .88em;
}
.content code { background: #0b0f18; padding: 1px 5px; border-radius: 4px; font-size: .9em; }
.content pre code { background: none; padding: 0; }
.task-box, .test-box {
  margin-top: 28px; background: var(--panel); border: 1px solid var(--border);
  border-radius: 12px; padding: 20px;
}
.task-box { border-left: 4px solid var(--warn); }
.test-box { border-left: 4px solid var(--accent); }
.deliverable { color: var(--muted); }
.muted { color: var(--muted); }
.field { margin: 12px 0; }
.field label { display: block; margin-bottom: 4px; font-weight: 600; }
.field input {
  width: 100%; max-width: 420px; padding: 9px 12px; border-radius: 8px;
  border: 1px solid var(--border); background: var(--panel2); color: var(--text); font-size: 1em;
}
.questions { padding-left: 22px; }
.question { margin-bottom: 18px; }
.question p { margin: 0 0 8px; font-weight: 600; }
.level { font-size: .75em; font-weight: 600; border-radius: 5px; padding: 1px 7px; margin-right: 6px; }
.level-básica { color: var(--ok); }
.level-media { color: var(--warn); }
.level-avanzada { color: var(--ko); }
.options { display: grid; gap: 6px; }
.option {
  display: flex; gap: 10px; align-items: baseline; background: var(--panel2);
  border: 1px solid var(--border); border-radius: 8px; padding: 8px 12px; cursor: pointer;
}
.option:hover { border-color: var(--accent); }
.option input { margin-top: 2px; }
.test-actions { display: flex; align-items: center; gap: 14px; margin-top: 8px; }
button.primary {
  background: var(--accent); color: #fff; border: none; border-radius: 8px;
  padding: 11px 22px; font-size: 1em; font-weight: 600; cursor: pointer;
}
button.primary:disabled { opacity: .6; cursor: default; }
.warning { color: var(--warn); }
.result { margin-top: 18px; border-radius: 10px; padding: 16px; }
.result.pass { background: #10301f; border: 1px solid var(--ok); }
.result.fail { background: #351918; border: 1px solid var(--ko); }
.corrections { padding-left: 20px; }
.corrections li { margin: 4px 0; font-size: .94em; }
.corrections .ok { color: var(--ok); }
.corrections .ko { color: #f0b0ab; }
footer { text-align: center; color: var(--muted); padding: 32px; font-size: .85em; }

/* ---- Admin ---- */
.admin-top { display: flex; gap: 12px; align-items: center; flex-wrap: wrap; margin-bottom: 18px; }
.admin-top input { padding: 8px 12px; border-radius: 8px; border: 1px solid var(--border); background: var(--panel2); color: var(--text); }
.admin-top button, .admin-top a.btn {
  background: var(--panel2); color: var(--text); border: 1px solid var(--border);
  border-radius: 8px; padding: 8px 14px; cursor: pointer; text-decoration: none; font-size: .95em;
}
.admin-top button:hover, .admin-top a.btn:hover { border-color: var(--accent); }
table.admin { border-collapse: collapse; width: 100%; font-size: .92em; }
table.admin th, table.admin td { border: 1px solid var(--border); padding: 7px 10px; text-align: left; }
table.admin th { background: var(--panel2); position: sticky; top: 0; }
tr.fail-row td { color: #f0b0ab; }
.admin h2 { color: var(--accent); margin-top: 30px; }
.toggle-btn { cursor: pointer; background: var(--panel2); border: 1px solid var(--border); color: var(--text); border-radius: 6px; padding: 4px 10px; }
.stats { display: flex; gap: 12px; flex-wrap: wrap; margin: 12px 0; }
.stat { background: var(--panel); border: 1px solid var(--border); border-radius: 10px; padding: 10px 18px; }
.stat b { font-size: 1.4em; display: block; }

/* Pestañas del panel */
.tabs { display: flex; gap: 6px; flex-wrap: wrap; margin: 16px 0 20px; border-bottom: 1px solid var(--border); padding-bottom: 10px; }
.tabs button {
  background: var(--panel2); color: var(--text); border: 1px solid var(--border);
  border-radius: 8px 8px 0 0; padding: 9px 16px; cursor: pointer; font-size: .95em;
}
.tabs button.active { background: var(--accent); color: #fff; border-color: var(--accent); }
.tabs button:hover:not(.active) { border-color: var(--accent); }

/* Barras de progreso */
.bar {
  display: inline-block; width: 110px; height: 10px; background: var(--panel2);
  border-radius: 999px; overflow: hidden; vertical-align: middle;
}
.bar-fill { display: block; height: 100%; border-radius: 999px; }

/* Filas expandibles y paneles */
tr.clickable { cursor: pointer; }
tr.clickable:hover td { background: var(--panel2); }
.panel-box {
  background: var(--panel); border: 1px solid var(--border); border-radius: 12px;
  padding: 16px 20px; margin: 16px 0;
}
.two-cols { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
@media (max-width: 800px) { .two-cols { grid-template-columns: 1fr; } }
.mini-list { display: grid; gap: 8px; }
.mini-row { display: flex; align-items: center; gap: 10px; flex-wrap: wrap; }
.mini-row .mini-name { flex: 1 1 260px; }
.check { display: flex; gap: 8px; align-items: center; color: var(--muted); cursor: pointer; }