:root{--bg:#f4f6f9;--card:#fff;--ink:#16202c;--muted:#5d6b7b;--brand:#123f73;--brand2:#1d6fb8;--ok:#177245;--bad:#b3261e;--warn:#8a5a00;--line:#d9e0e8;--code:#0d1520}
*{box-sizing:border-box}html,body{margin:0}body{font:15px/1.5 system-ui,-apple-system,"Segoe UI",Roboto,Arial,sans-serif;background:var(--bg);color:var(--ink)}
a{color:var(--brand2)}code{background:#eef2f6;padding:1px 5px;border-radius:4px;font-size:90%}
.top{display:flex;justify-content:space-between;align-items:center;gap:16px;padding:10px 24px;background:var(--brand);color:#fff;flex-wrap:wrap}
.top a{color:#fff;text-decoration:none;margin-left:14px}.top nav{display:flex;align-items:center;flex-wrap:wrap}
.brand{display:flex;align-items:center;gap:10px;font-size:18px;margin-left:0!important}.logo{background:#fff;color:var(--brand);font-weight:800;border-radius:6px;padding:2px 7px}
.wrap{max-width:1100px;margin:24px auto;padding:0 16px}.wide{max-width:1600px;margin:16px auto;padding:0 16px}
.foot{color:var(--muted);text-align:center;font-size:13px;padding:24px 16px}
.card{background:var(--card);border:1px solid var(--line);border-radius:10px;padding:18px 20px;margin:0 0 16px}.card.tight{padding:12px 14px}
.card.ok{border-left:6px solid var(--ok)}.card.bad{border-left:6px solid var(--bad)}.narrow{max-width:620px;margin:0 auto 16px}
.grid3{display:grid;grid-template-columns:repeat(auto-fit,minmax(260px,1fr));gap:16px}.grid4{display:grid;grid-template-columns:repeat(auto-fit,minmax(180px,1fr));gap:16px}
.stat b{display:block;font-size:30px}.stat span{color:var(--muted)}
.hero{padding:28px 0 8px}.hero h1{font-size:34px;margin:0 0 8px}.lead{font-size:18px;color:#2b3a4b}.cta{margin:18px 0}
.btn{display:inline-block;background:var(--brand2);color:#fff;border:0;border-radius:8px;padding:9px 16px;font:inherit;font-weight:600;cursor:pointer;text-decoration:none}
.btn.ghost{background:#fff;color:var(--brand2);border:1px solid var(--brand2)}.btn.small{padding:5px 11px;font-size:14px}.btn.danger{background:var(--bad)}
.btn:disabled{opacity:.5;cursor:wait}.link{background:none;border:0;color:#fff;cursor:pointer;font:inherit;margin-left:14px}.inline{display:inline}
.form label{display:block;margin:10px 0;font-weight:600}.form input,.form textarea,.form select{display:block;width:100%;margin-top:4px}
input,textarea,select{font:inherit;padding:7px 9px;border:1px solid #b8c3cf;border-radius:6px;background:#fff;color:var(--ink)}
textarea{width:100%;font-family:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;font-size:13px}
label.check{font-weight:400;display:flex;gap:8px;align-items:flex-start}label.check input{width:auto;margin-top:4px}
.row{display:flex;gap:10px;align-items:center;flex-wrap:wrap;margin:8px 0}.row label{font-weight:600}.grow{flex:1;min-width:220px}
.flash{background:#e7f1fb;border:1px solid #b6d3ef;padding:10px 14px;border-radius:8px;margin-bottom:14px}
.errors{background:#fdecea;border:1px solid #f1b7b2;padding:6px 14px;border-radius:8px;margin-bottom:14px;color:var(--bad)}
.warn{color:var(--warn);font-weight:600}.muted{color:var(--muted);font-weight:400}
.tbl{width:100%;border-collapse:collapse;font-size:14px}.tbl th,.tbl td{border-bottom:1px solid var(--line);padding:6px 8px;text-align:left;vertical-align:top}
.kv th{text-align:left;padding:5px 14px 5px 0;color:var(--muted);font-weight:600}.kv td{padding:5px 0}
.badge{display:inline-block;padding:4px 12px;border-radius:20px;font-weight:700;color:#fff}.badge.ok{background:var(--ok)}.badge.bad{background:var(--bad)}
.pill{display:inline-block;background:#e8eef5;color:#2b3a4b;border-radius:12px;padding:1px 9px;font-size:12px;font-weight:600;margin-left:6px}
.checks{list-style:none;padding:0;margin:0}.checks li{padding:3px 0 3px 22px;position:relative}.checks li:before{content:"";position:absolute;left:4px;top:9px;width:10px;height:10px;border-radius:50%;background:#aab4bf}
.checks li.ok:before{background:var(--ok)}.checks li.bad:before{background:var(--bad)}
fieldset{border:1px solid var(--line);border-radius:8px;margin:12px 0;padding:8px 12px}legend{font-weight:600}
pre{white-space:pre-wrap;word-break:break-word}pre.stmt{background:#f7f9fb;border:1px solid var(--line);border-radius:6px;padding:10px;font-family:inherit;margin:8px 0}
pre.out{background:var(--code);color:#d7e3ee;border-radius:8px;padding:10px;min-height:40px;max-height:420px;overflow:auto;font-size:12.5px}
.timer{font:700 22px ui-monospace,Menlo,Consolas,monospace}.timer.low{color:var(--bad)}
.exambar{display:flex;justify-content:space-between;align-items:center;gap:12px;flex-wrap:wrap;background:#fff;border:1px solid var(--line);border-radius:10px;padding:10px 14px;margin-bottom:10px;position:sticky;top:0;z-index:5}
.msg:empty{display:none}.msg{background:#fff6df;border:1px solid #f0d48a;border-radius:8px;padding:8px 12px;margin-bottom:10px}
.examgrid{display:grid;grid-template-columns:minmax(340px,520px) 1fr;gap:14px}@media(max-width:1000px){.examgrid{grid-template-columns:1fr}}
.tabs{display:flex;gap:4px;flex-wrap:wrap;margin-bottom:8px}.tab{border:1px solid var(--line);background:#fff;border-radius:8px 8px 0 0;padding:7px 14px;cursor:pointer;font:inherit}
.tab.active{background:var(--brand);color:#fff;border-color:var(--brand)}.pane{display:none}.pane.active{display:block}
.topo{width:100%;height:auto}.topo .lnk{stroke:#8ea2b8;stroke-width:3}.topo .node rect{fill:#e9f0f8;stroke:#4d6b8a;stroke-width:1.5}.topo .node text{font:700 20px system-ui;text-anchor:middle;fill:#14263a}
.topo .node{cursor:pointer}.topo .node.core rect{fill:#d6e4f5}.topo .node.pe rect{fill:#dff0e6}.topo .node.rr rect{fill:#efe4f7}.topo .node.ce rect{fill:#fff4dc}.topo .node.ext rect{fill:#f1f1f1}
.topo .node.down rect{stroke:var(--bad);stroke-width:3}.topo .node:hover rect,.topo .node:focus rect{stroke:var(--brand2);stroke-width:3}
.termtabs{margin-bottom:6px}.termtabs .tt{display:inline-flex;align-items:center;gap:6px;border:1px solid var(--line);background:#fff;border-radius:6px;padding:3px 8px;margin:2px;cursor:pointer}
.termtabs .tt.active{background:var(--brand2);color:#fff}.termtabs .tt b{cursor:pointer}.term{display:none;height:520px;background:#000;border-radius:8px;padding:4px}.term.active{display:block}
progress{width:160px;vertical-align:middle}
.testmode{background:#8a5a00;color:#fff;text-align:center;font-weight:700;padding:6px 12px;font-size:14px}

/* consola: respaldo legible si el tema de xterm no se aplica (los selectores de xterm tienen más especificidad) */
.term .xterm,.term .xterm-viewport,.term .xterm-screen{background:#000}.term .xterm .xterm-rows{color:#f2f2f2}
.term .xterm-rows .xterm-cursor.xterm-cursor-block{background:#7CFC8A;color:#000}