/* Layout: one working column for students (reading beside the question on wide screens); a dense table for the teacher. */
:root {
  --paper: #f3f4ff;
  --card: #ffffff;
  --ink: #1f1d3d;
  --muted: #5f5c80;
  --line: #dcdaf2;
  --accent: #5b4bdb;
  --accent-ink: #ffffff;
  --good: #0f8a66;
  --good-bg: #ddf5ec;
  --warn: #a35a00;
  --warn-bg: #fff0d9;
  --bad: #c22f4f;
  --bad-bg: #fde4ea;
  --starter: #0f8a66;
  --explorer: #d9601f;
  --challenger: #a332c4;
  --track: #e8e7f7;
  --ill-sky: #e9e6ff;
  --ill-ground: #d8f0e6;
  --display: "Bricolage Grotesque", "Segoe UI", system-ui, sans-serif;
  --body: "Nunito", "Segoe UI", system-ui, sans-serif;
  --read: "Nunito", "Segoe UI", system-ui, sans-serif;
  --mono: "IBM Plex Mono", ui-monospace, Consolas, monospace;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --paper: #15142a; --card: #1f1d3a; --ink: #eceaff; --muted: #a9a6cc; --line: #35325a;
    --accent: #9d92ff; --accent-ink: #15142a;
    --good: #5ad3a6; --good-bg: #173a30; --warn: #f2b45a; --warn-bg: #3d2c12; --bad: #ff8aa3; --bad-bg: #44202b;
    --starter: #5ad3a6; --explorer: #ff9a5c; --challenger: #d58cf0; --track: #2b2950;
    --ill-sky: #d4cff7; --ill-ground: #c3e6d6;
    color-scheme: dark;
  }
}
:root[data-theme="dark"] {
  --paper: #15142a; --card: #1f1d3a; --ink: #eceaff; --muted: #a9a6cc; --line: #35325a;
  --accent: #9d92ff; --accent-ink: #15142a;
  --good: #5ad3a6; --good-bg: #173a30; --warn: #f2b45a; --warn-bg: #3d2c12; --bad: #ff8aa3; --bad-bg: #44202b;
  --starter: #5ad3a6; --explorer: #ff9a5c; --challenger: #d58cf0; --track: #2b2950;
  --ill-sky: #d4cff7; --ill-ground: #c3e6d6;
  color-scheme: dark;
}
* { box-sizing: border-box; }
body { background: var(--paper); color: var(--ink); font: 16px/1.55 var(--body); }
.wrap { max-width: 1080px; margin: 0 auto; padding-left: max(16px, env(safe-area-inset-left, 0px)); padding-right: max(16px, env(safe-area-inset-right, 0px)); padding-block: 20px 48px; }
header.top { display: flex; flex-wrap: wrap; gap: 12px 24px; align-items: center; justify-content: space-between; padding-block: 8px 20px; border-bottom: 1px solid var(--line); margin-bottom: 28px; }
.brand { display: flex; align-items: baseline; gap: 10px; flex-wrap: wrap; }
.brand h1 { font: 800 1.5rem/1.1 var(--display); margin: 0; letter-spacing: -0.01em; }
.brand span { color: var(--muted); font-size: .85rem; }
nav.tabs { display: flex; gap: 4px; background: var(--track); padding: 4px; border-radius: 10px; }
nav.tabs button { border: 0; background: transparent; color: var(--muted); font: 500 .9rem var(--body); padding: 8px 14px; border-radius: 7px; cursor: pointer; }
nav.tabs button[aria-selected="true"] { background: var(--card); color: var(--ink); box-shadow: 0 1px 2px rgba(0,0,0,.08); }
h2 { font: 800 1.75rem/1.15 var(--display); margin: 0 0 8px; text-wrap: balance; }
h3 { font: 600 1.1rem/1.3 var(--display); margin: 0 0 8px; }
p { margin: 0 0 12px; }
.lead { color: var(--muted); max-width: 62ch; }
.eyebrow { font: 600 .75rem var(--body); letter-spacing: .08em; text-transform: uppercase; color: var(--muted); }
.stack { display: flex; flex-direction: column; gap: 16px; }
.row { display: flex; flex-wrap: wrap; gap: 12px; align-items: center; }
.panel { background: var(--card); border: 1px solid var(--line); border-radius: 16px; padding: 20px; }
.narrow { max-width: 720px; }
button.btn { font: 800 1rem var(--body); border-radius: 999px; padding: 11px 20px; cursor: pointer; border: 1px solid var(--accent); background: var(--accent); color: var(--accent-ink); }
button.btn.ghost { background: transparent; color: var(--accent); }
button.btn.small { padding: 7px 12px; font-size: .85rem; }
button.btn.danger { border-color: var(--bad); color: var(--bad); background: transparent; }
button.btn:disabled { opacity: .45; cursor: not-allowed; }
button:focus-visible, input:focus-visible, textarea:focus-visible, select:focus-visible { outline: 3px solid var(--accent); outline-offset: 2px; }
label.field { display: flex; flex-direction: column; gap: 6px; font-weight: 500; }
input[type=text], textarea, select { font: 1rem var(--body); padding: 10px 12px; border: 1px solid var(--line); border-radius: 8px; background: var(--card); color: var(--ink); }
input#codigo { font: 500 1.3rem var(--mono); max-width: 220px; text-transform: uppercase; }
.progress { display: flex; align-items: center; gap: 12px; color: var(--muted); font-size: .9rem; }
.progress .bar { flex: 1; height: 6px; background: var(--track); border-radius: 3px; overflow: hidden; }
.progress .bar i { display: block; height: 100%; background: var(--accent); }
.passage { font: 1.1rem/1.7 var(--read); background: var(--card); border: 1px solid var(--line); border-radius: 16px; padding: 20px 22px; }
.passage p { margin: 0 0 10px; }
.passage p:last-child { margin: 0; }
.passage .tit { font: 800 1.45rem/1.2 var(--display); margin-bottom: 12px; }
.ill { border-radius: 14px; overflow: hidden; line-height: 0; margin: -4px 0 14px; }
.ill svg { width: 100%; height: auto; display: block; }
.hero-ill { border-radius: 16px; overflow: hidden; line-height: 0; }
.hero-ill svg { width: 100%; height: auto; display: block; }
.gloss { display: flex; flex-wrap: wrap; gap: 6px 14px; margin-top: 14px; padding-top: 12px; border-top: 1px dashed var(--line); font: .85rem var(--body); color: var(--muted); }
.gloss b { color: var(--ink); font-weight: 600; }
.qtext { font: 600 1.15rem/1.4 var(--body); margin-bottom: 14px; }
.opts { display: flex; flex-direction: column; gap: 10px; }
.opt { display: flex; gap: 12px; align-items: flex-start; text-align: left; width: 100%; font: 600 1.02rem/1.45 var(--body); padding: 13px 15px; border: 2px solid var(--line); border-radius: 14px; background: var(--card); color: var(--ink); cursor: pointer; }
.opt .k { font: 600 .9rem var(--mono); min-width: 1.6em; height: 1.6em; display: inline-grid; place-items: center; border-radius: 6px; background: var(--track); color: var(--muted); flex: none; }
.opt:hover:not(:disabled) { border-color: var(--accent); }
.opt[aria-pressed="true"] { border-color: var(--accent); box-shadow: inset 0 0 0 1px var(--accent); }
.opt[aria-pressed="true"] .k { background: var(--accent); color: var(--accent-ink); }
.opt.right { border-color: var(--good); background: var(--good-bg); }
.opt.right .k { background: var(--good); color: var(--card); }
.opt.wrong { border-color: var(--bad); background: var(--bad-bg); }
.opt.wrong .k { background: var(--bad); color: var(--card); }
.opt:disabled { cursor: default; }
.fb { border-radius: 10px; padding: 12px 14px; font-size: .97rem; }
.fb.ok { background: var(--good-bg); color: var(--ink); border-left: 4px solid var(--good); }
.fb.no { background: var(--warn-bg); color: var(--ink); border-left: 4px solid var(--warn); }
.fb strong { display: block; margin-bottom: 2px; }
.practice { display: grid; grid-template-columns: minmax(0, 1.15fr) minmax(0, 1fr); gap: 24px; align-items: start; }
.practice .passage { position: sticky; top: 12px; max-height: calc(100vh - 24px); overflow: auto; }
@media (max-width: 820px) { .practice { grid-template-columns: minmax(0, 1fr); } .practice .passage { position: static; max-height: none; } }
.route { border-radius: 12px; padding: 20px; border: 2px solid var(--rc); background: var(--card); }
.route .name { font: 800 2.2rem/1 var(--display); color: var(--rc); }
.chip { display: inline-flex; align-items: center; gap: 6px; font: 600 .8rem var(--body); padding: 3px 10px; border-radius: 999px; border: 1px solid var(--rc, var(--line)); color: var(--rc, var(--muted)); white-space: nowrap; }
.objs { display: flex; flex-direction: column; gap: 12px; }
.obj { display: grid; grid-template-columns: minmax(0, 1fr) auto; gap: 4px 12px; align-items: center; }
.obj .lbl { font-size: .92rem; }
.obj .val { font: 500 .9rem var(--mono); font-variant-numeric: tabular-nums; color: var(--muted); }
.obj .meter { grid-column: 1 / -1; height: 8px; border-radius: 4px; background: var(--track); overflow: hidden; position: relative; }
.obj .meter i { position: absolute; inset: 0 auto 0 0; background: var(--accent); border-radius: 4px; }
.obj .meter.pre i { background: var(--muted); }
.obj .meter.low i { background: var(--warn); }
.cmp { display: grid; grid-template-columns: minmax(0, 1fr); gap: 3px; grid-column: 1 / -1; }
.sus { display: flex; flex-direction: column; gap: 14px; }
.sus fieldset { border: 0; padding: 0; margin: 0; }
.sus legend { font-weight: 500; margin-bottom: 6px; padding: 0; }
.scale { display: grid; grid-template-columns: repeat(5, minmax(0, 1fr)); gap: 6px; }
.scale label { display: flex; flex-direction: column; align-items: center; gap: 2px; padding: 8px 4px; border: 1px solid var(--line); border-radius: 8px; cursor: pointer; font: .78rem/1.2 var(--body); color: var(--muted); text-align: center; }
.scale input { accent-color: var(--accent); }
.scale label:has(input:checked) { border-color: var(--accent); color: var(--ink); background: color-mix(in srgb, var(--accent) 10%, var(--card)); }
.scale .n { font: 600 1rem var(--mono); color: var(--ink); }
.scale-legend { display: flex; justify-content: space-between; font-size: .78rem; color: var(--muted); }
.status { font-size: .85rem; color: var(--muted); display: inline-flex; align-items: center; gap: 6px; }
.status i { width: 8px; height: 8px; border-radius: 50%; background: var(--warn); display: inline-block; }
.status.on i { background: var(--good); }
.tiles { display: grid; grid-template-columns: repeat(auto-fit, minmax(160px, 1fr)); gap: 12px; }
.tile { background: var(--card); border: 1px solid var(--line); border-radius: 10px; padding: 14px 16px; }
.tile .v { font: 700 1.7rem/1.1 var(--display); font-variant-numeric: tabular-nums; }
.tile .l { font-size: .82rem; color: var(--muted); }
.tablewrap { overflow-x: auto; border: 1px solid var(--line); border-radius: 10px; background: var(--card); }
table { border-collapse: collapse; width: 100%; font-size: .9rem; }
th, td { padding: 10px 12px; text-align: left; border-bottom: 1px solid var(--line); white-space: nowrap; }
th { font: 600 .75rem var(--body); letter-spacing: .06em; text-transform: uppercase; color: var(--muted); background: color-mix(in srgb, var(--track) 60%, var(--card)); }
td.num { font-family: var(--mono); font-variant-numeric: tabular-nums; }
tbody tr { cursor: pointer; }
tbody tr:hover td { background: color-mix(in srgb, var(--accent) 6%, var(--card)); }
tbody tr[aria-selected="true"] td { background: color-mix(in srgb, var(--accent) 12%, var(--card)); }
tr:last-child td { border-bottom: 0; }
.delta.up { color: var(--good); font-weight: 600; }
.delta.down { color: var(--bad); font-weight: 600; }
.empty { text-align: center; padding: 36px 16px; color: var(--muted); }
.mini { font-size: .85rem; color: var(--muted); }
.mono { font-family: var(--mono); }
.detail-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 16px; }
.resp { display: grid; grid-template-columns: auto minmax(0, 1fr) auto auto; gap: 4px 10px; font-size: .85rem; align-items: baseline; }
.resp .ok { color: var(--good); font-weight: 600; }
.resp .no { color: var(--bad); font-weight: 600; }
details summary { cursor: pointer; font-weight: 600; }
textarea { width: 100%; min-height: 90px; resize: vertical; }
.toast { position: fixed; left: 50%; bottom: calc(20px + env(safe-area-inset-bottom, 0px)); transform: translateX(-50%); background: var(--ink); color: var(--paper); padding: 10px 16px; border-radius: 8px; font-size: .9rem; z-index: 20; max-width: calc(100% - 32px); }
@media (prefers-reduced-motion: no-preference) { .screen { animation: in .25s ease-out; } @keyframes in { from { opacity: .4; transform: translateY(4px); } to { opacity: 1; transform: none; } } }

/* ---------- server version additions ---------- */
input.codigo { font: 500 1.3rem var(--mono); width: 100%; max-width: 220px; text-transform: uppercase; }
.campos { align-items: flex-start; }
.campos .field { flex: 1 1 160px; }
.sesion-bar { display: flex; flex-wrap: wrap; align-items: center; gap: 8px 14px; font-size: .9rem; }
.sesion-bar:empty { display: none; }
.aviso { border-color: var(--warn); background: var(--warn-bg); }
.pie { margin-top: 40px; padding-top: 16px; border-top: 1px solid var(--line); font-size: .85rem; color: var(--muted); display: flex; flex-wrap: wrap; gap: 8px 20px; }
a { color: var(--accent); }
.login { max-width: 380px; }
.login input[type=password], .login input[type=text] { width: 100%; }
input[type=password] { font: 1rem var(--body); padding: 10px 12px; border: 1px solid var(--line); border-radius: 8px; background: var(--card); color: var(--ink); }
.error { color: var(--bad); font-weight: 600; }
.filtros { display: flex; flex-wrap: wrap; gap: 12px 20px; align-items: center; }
.filtros select { min-width: 140px; }
a.btn { display: inline-block; text-decoration: none; font: 800 .85rem var(--body); border-radius: 999px; padding: 7px 12px; border: 1px solid var(--accent); color: var(--accent); }
.doc { max-width: 72ch; }
.doc h2 { margin-top: 28px; font-size: 1.3rem; }
.doc li { margin-bottom: 6px; }
.borrador { border: 2px dashed var(--warn); background: var(--warn-bg); border-radius: 12px; padding: 12px 16px; font-weight: 700; }