:root {
  --bg: #f4f6fb;
  --card: #ffffff;
  --ink: #18203a;
  --muted: #5e6787;
  --line: #e1e5f0;
  --brand: #2f5bea;
  --brand-ink: #ffffff;
  --brand-soft: #e6ecff;
  --ok: #17a467;
  --ok-soft: #dcf6ea;
  --bad: #e0464b;
  --bad-soft: #fde4e4;
  --warn: #f4a52a;
  --shadow: 0 2px 0 rgba(24, 32, 58, .06), 0 8px 24px rgba(24, 32, 58, .06);
  --radius: 18px;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #11152a; --card: #1b2140; --ink: #eef1ff; --muted: #a3abcf; --line: #2c3460;
    --brand: #6f8dff; --brand-ink: #0d1126; --brand-soft: #253063;
    --ok: #3fd18e; --ok-soft: #173d31; --bad: #ff7276; --bad-soft: #4a2228;
    --shadow: none;
  }
}

* { box-sizing: border-box; }
html, body { margin: 0; }
body {
  background: var(--bg);
  color: var(--ink);
  font-family: "Nunito", system-ui, -apple-system, "Segoe UI", sans-serif;
  font-size: 17px;
  line-height: 1.45;
  min-height: 100dvh;
  -webkit-tap-highlight-color: transparent;
}
button, input, textarea, select { font: inherit; color: inherit; }

/* --- barra superior --- */
.topbar {
  padding-left: clamp(12px, 1.5vw, 24px) !important; padding-right: clamp(12px, 1.5vw, 24px) !important;
  position: sticky; top: 0; z-index: 5;
  display: flex; align-items: center; justify-content: space-between;
  padding: 10px 16px; padding-top: max(10px, env(safe-area-inset-top));
  background: color-mix(in srgb, var(--bg) 85%, transparent);
  backdrop-filter: blur(8px);
}
.brand { display: flex; align-items: center; gap: 8px; font-weight: 900; font-size: 20px; color: var(--ink); text-decoration: none; }
.brand-mark {
  display: grid; place-items: center; width: 34px; height: 34px; border-radius: 10px;
  background: var(--brand); color: var(--brand-ink); font-weight: 900;
}
.stats { display: flex; gap: 8px; }
.pill { background: var(--card); border: 1px solid var(--line); border-radius: 999px; padding: 4px 12px; font-weight: 800; font-size: 15px; }

main { width: 100%; margin: 0 auto; padding: 8px clamp(12px, 1.5vw, 24px) 48px; }

/* --- tarjetas y botones --- */
.card { background: var(--card); border-radius: var(--radius); box-shadow: var(--shadow); border: 1px solid var(--line); padding: 18px; margin: 12px 0; }
h1 { font-size: 26px; font-weight: 900; margin: 12px 0 4px; }
h2 { font-size: 20px; font-weight: 900; margin: 0 0 10px; }
.muted { color: var(--muted); }
.small { font-size: 14px; }
.row { display: flex; gap: 10px; flex-wrap: wrap; align-items: center; }
.grow { flex: 1; }

.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  border: 0; border-radius: 14px; padding: 13px 18px; min-height: 48px;
  font-weight: 800; cursor: pointer; background: var(--brand-soft); color: var(--ink);
  box-shadow: inset 0 -3px 0 rgba(0,0,0,.08); transition: transform .06s; text-decoration: none;
}
.btn:active { transform: translateY(2px); box-shadow: none; }
.btn.primary { background: var(--brand); color: var(--brand-ink); }
.btn.ok { background: var(--ok); color: #fff; }
.btn.bad { background: var(--bad); color: #fff; }
.btn.ghost { background: transparent; box-shadow: none; border: 1px solid var(--line); }
.btn.block { width: 100%; }
.btn.big { font-size: 19px; min-height: 58px; }
.btn[disabled] { opacity: .5; pointer-events: none; }
.icon-btn { width: 52px; height: 52px; padding: 0; border-radius: 50%; font-size: 22px; }

.chips { display: flex; gap: 8px; flex-wrap: wrap; }
.chip { border: 2px solid var(--line); background: var(--card); border-radius: 12px; padding: 6px 14px; font-weight: 800; cursor: pointer; }
.chip.on { border-color: var(--brand); background: var(--brand-soft); }

.menu { display: grid; gap: 10px; }
.menu .btn { justify-content: flex-start; text-align: left; padding: 14px 18px; }
.menu .btn small { display: block; font-weight: 600; opacity: .8; }
.menu .emoji { font-size: 26px; width: 34px; text-align: center; }

.bar { height: 12px; background: var(--line); border-radius: 999px; overflow: hidden; }
.bar > i { display: block; height: 100%; background: var(--ok); border-radius: 999px; transition: width .4s; }

/* --- ejercicio --- */
.ex-head { display: flex; align-items: center; gap: 12px; margin: 8px 0 4px; }
.ex-head .bar { flex: 1; }
.ex-label { font-size: 14px; font-weight: 800; text-transform: uppercase; letter-spacing: .04em; color: var(--muted); margin: 10px 0 0; }
.prompt { font-size: 32px; font-weight: 900; text-align: center; margin: 14px 0 4px; word-break: break-word; }
.prompt.sentence { font-size: 22px; font-weight: 700; }
.ipa { text-align: center; color: var(--muted); font-size: 18px; }
.center { display: flex; justify-content: center; gap: 12px; margin: 12px 0; flex-wrap: wrap; }

.options { display: grid; gap: 10px; margin-top: 16px; }
.opt {
  border: 2px solid var(--line); background: var(--card); border-radius: 14px;
  padding: 14px; font-weight: 800; font-size: 18px; cursor: pointer; text-align: center; min-height: 56px;
}
.opt.right { border-color: var(--ok); background: var(--ok-soft); }
.opt.wrong { border-color: var(--bad); background: var(--bad-soft); }
.opt[disabled] { cursor: default; }

.match { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; margin-top: 16px; }
.match .opt { font-size: 16px; padding: 12px 8px; }
.opt.sel { border-color: var(--brand); background: var(--brand-soft); }
.opt.done { opacity: .35; border-color: var(--ok); }

.flash {
  perspective: 1000px; min-height: 340px; cursor: pointer; margin-top: 12px;
}
.flash-inner { position: relative; min-height: 340px; transition: transform .45s; transform-style: preserve-3d; }
.flash.flipped .flash-inner { transform: rotateY(180deg); }
.face {
  position: absolute; inset: 0; backface-visibility: hidden; -webkit-backface-visibility: hidden;
  background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); box-shadow: var(--shadow);
  display: flex; flex-direction: column; justify-content: center; align-items: center; padding: 18px; text-align: center; overflow-y: auto;
}
.face.back { transform: rotateY(180deg); }
.face .es { font-size: 28px; font-weight: 900; color: var(--brand); }
.face .def { margin-top: 8px; }
.face .exs { margin-top: 8px; font-style: italic; color: var(--muted); }
.tag { display: inline-block; font-size: 13px; font-weight: 800; padding: 2px 10px; border-radius: 999px; background: var(--brand-soft); margin-bottom: 6px; }

.input {
  width: 100%; padding: 14px 16px; border-radius: 14px; border: 2px solid var(--line);
  background: var(--card); font-size: 22px; font-weight: 800; text-align: center; letter-spacing: .02em;
}
.input:focus { outline: none; border-color: var(--brand); }
textarea.input { font-size: 16px; font-weight: 600; text-align: left; min-height: 200px; letter-spacing: 0; }
select.input { font-size: 16px; text-align: left; padding: 10px 12px; }

.feedback { margin-top: 14px; padding: 14px; border-radius: 14px; font-weight: 800; text-align: center; }
.feedback.ok { background: var(--ok-soft); color: var(--ok); }
.feedback.bad { background: var(--bad-soft); color: var(--bad); }
.feedback .answer { display: block; color: var(--ink); font-size: 20px; margin-top: 4px; }
.diff b { color: var(--bad); text-decoration: underline; }

.mic { width: 96px; height: 96px; border-radius: 50%; font-size: 40px; }
.mic.rec { background: var(--bad); color: #fff; animation: pulse 1s infinite; }
@keyframes pulse { 50% { transform: scale(1.06); } }

/* --- resultados --- */
.result { text-align: center; }
.result .big-num { font-size: 56px; font-weight: 900; color: var(--brand); }

/* --- tablas admin --- */
table { width: 100%; border-collapse: collapse; font-size: 15px; }
th, td { text-align: left; padding: 8px 6px; border-bottom: 1px solid var(--line); vertical-align: top; }
th { color: var(--muted); font-size: 13px; text-transform: uppercase; }
.box-dot { display: inline-block; width: 12px; height: 12px; border-radius: 50%; margin-right: 2px; background: var(--line); }
.box-dot.on { background: var(--ok); }
.word-row input { width: 100%; border: 1px solid var(--line); border-radius: 8px; padding: 6px 8px; background: var(--bg); font-size: 15px; }
.tabs { display: flex; gap: 8px; margin: 10px 0; }
.kpis { display: grid; grid-template-columns: repeat(3, 1fr); gap: 10px; }
.kpi { background: var(--card); border: 1px solid var(--line); border-radius: 14px; padding: 12px; text-align: center; }
.kpi b { display: block; font-size: 26px; font-weight: 900; }
.scroll-x { overflow-x: auto; }

#toast {
  position: fixed; left: 50%; bottom: 24px; transform: translateX(-50%) translateY(120px);
  background: var(--ink); color: var(--bg); padding: 12px 18px; border-radius: 14px; font-weight: 800;
  transition: transform .25s, visibility .25s; max-width: calc(100% - 32px); z-index: 20; visibility: hidden;
}
#toast.show { transform: translateX(-50%) translateY(0); visibility: visible; }

@media (min-width: 520px) {
  .options.two { grid-template-columns: 1fr 1fr; }
}

/* --- v4: fonética y verbos --- */
.phon { text-align: center; font-weight: 800; font-size: 18px; color: var(--brand); margin-top: 4px; }
table.forms { margin: 10px auto 0; width: auto; font-size: 15px; }
table.forms th, table.forms td { text-align: center; padding: 4px 10px; }
table.forms td { font-weight: 800; }
.input.good { border-color: var(--ok); background: var(--ok-soft); }
.input.badin { border-color: var(--bad); background: var(--bad-soft); }

/* --- duplicadas --- */
.dup-groups { display: grid; gap: 8px; margin-top: 10px; color: var(--ink); font-weight: 600; }
.dup-group { background: var(--card); border: 1px solid var(--line); border-radius: 12px; padding: 10px 12px; }
.dup-item { padding: 4px 0; border-top: 1px solid var(--line); margin-top: 6px; }

/* ===== Pantallas grandes (portátiles de 14" y superiores) =====
   Se ocupa todo el ancho dejando un margen mínimo a los lados. */
@media (min-width: 900px) {
  body { font-size: 18px; }
  h1 { font-size: 32px; }
  .home-grid { display: grid; grid-template-columns: 3fr 2fr; gap: 20px; align-items: start; }
  .home-grid .card:first-child { margin-top: 0; }
  .home-grid .menu { margin-top: 0; }
  .menu .btn { min-height: 76px; }
  .prompt { font-size: 52px; margin-top: 2vh; }
  .prompt.sentence { font-size: 32px; }
  .ipa, .phon { font-size: 22px; }
  .options { gap: 14px; }
  .options.two { grid-template-columns: 1fr 1fr; }
  .opt { font-size: 22px; min-height: 76px; }
  .match { gap: 20px; }
  .match .opt { font-size: 20px; min-height: 64px; }
  .flash, .flash-inner { min-height: min(56vh, 520px); }
  .face .es { font-size: 40px; }
  .face .def, .face .exs { font-size: 20px; }
  .input { font-size: 28px; padding: 16px 20px; }
  textarea.input { font-size: 17px; min-height: 240px; }
  .btn.big { font-size: 21px; min-height: 64px; }
  .mic { width: 120px; height: 120px; font-size: 50px; }
  .icon-btn { width: 58px; height: 58px; font-size: 24px; }
  .feedback { font-size: 20px; }
  table.forms { font-size: 18px; }
  .result .big-num { font-size: 80px; }
  .kpis { grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 16px; }
  .scroll-x table { min-width: 100%; }
}
@media (min-width: 1300px) {
  .options.two { grid-template-columns: repeat(4, 1fr); }
}