/* =========================================================
   ESP4TH · Hoja de estilos
   Tema oscuro por defecto; el claro se activa con [data-theme="light"]
   ========================================================= */

:root,
:root[data-theme="dark"] {
  --bg: #0f1420;
  --bg-glow: #1a2340;
  --surface: #171e2e;
  --surface-2: #1f2840;
  --surface-3: #27324f;
  --border: #2a3550;
  --text: #e8ecf4;
  --muted: #9aa6bf;
  --accent: #ffb547;      /* dorado azafrán */
  --accent-ink: #1b1305;
  --accent-2: #ef5a6f;    /* rojo cálido */
  --ok: #4fd18b;
  --ok-bg: rgba(79, 209, 139, .12);
  --bad: #ff6b6b;
  --bad-bg: rgba(255, 107, 107, .12);
  --th-bg: rgba(255, 181, 71, .08);
  --th-border: rgba(255, 181, 71, .35);
  --shadow: 0 10px 30px rgba(0, 0, 0, .35);

  --c-vocabulario: #f48fb1;
  --c-gramatica: #7aa2ff;
  --c-ortografia: #5fd4b0;
  --c-verbos: #ffb547;
  --c-lectura: #c792ea;
  --c-escucha: #ff8a65;
  --c-sintaxis: #4fc3f7;
  color-scheme: dark;
}

:root[data-theme="light"] {
  --bg: #f7f5f0;
  --bg-glow: #fff1d6;
  --surface: #ffffff;
  --surface-2: #f2efe8;
  --surface-3: #e9e4d9;
  --border: #e0dacd;
  --text: #1b2130;
  --muted: #5d6578;
  --accent: #b86e00;
  --accent-ink: #ffffff;
  --accent-2: #c8102e;
  --ok: #138a4c;
  --ok-bg: rgba(19, 138, 76, .1);
  --bad: #c62828;
  --bad-bg: rgba(198, 40, 40, .08);
  --th-bg: rgba(184, 110, 0, .07);
  --th-border: rgba(184, 110, 0, .35);
  --shadow: 0 8px 24px rgba(27, 33, 48, .08);

  --c-vocabulario: #c2185b;
  --c-gramatica: #2f5fd0;
  --c-ortografia: #0f8a6a;
  --c-verbos: #b86e00;
  --c-lectura: #8a3fb8;
  --c-escucha: #d0512a;
  --c-sintaxis: #0b7fb3;
  color-scheme: light;
}

* { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  background:
    radial-gradient(1200px 500px at 85% -10%, var(--bg-glow), transparent 60%),
    var(--bg);
  background-attachment: fixed;
  color: var(--text);
  font-family: "Noto Sans", "Noto Sans Thai", system-ui, sans-serif;
  font-size: 16px;
  line-height: 1.6;
  transition: background-color .25s, color .25s;
}

h1, h2, h3, h4 {
  font-family: "Outfit", "Noto Sans Thai", system-ui, sans-serif;
  line-height: 1.2;
  margin: 0 0 .5em;
}

a { color: var(--accent); }

button { font: inherit; color: inherit; }

[lang="th"], .th { font-family: "Noto Sans Thai", "Noto Sans", sans-serif; }

.muted { color: var(--muted); }

svg { width: 1.2em; height: 1.2em; fill: none; stroke: currentColor; stroke-width: 2; stroke-linecap: round; stroke-linejoin: round; }

/* ---------- Barra superior ---------- */
.topbar {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 12px clamp(16px, 4vw, 40px);
  background: color-mix(in srgb, var(--bg) 82%, transparent);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}

.brand { display: flex; align-items: center; gap: 12px; text-decoration: none; color: var(--text); min-width: 0; }
.brand-mark {
  display: grid; place-items: center;
  width: 40px; height: 40px; flex: none;
  border-radius: 12px;
  background: var(--accent); color: var(--accent-ink);
  font: 800 24px/1 "Outfit", sans-serif;
}
.brand-text { display: flex; flex-direction: column; min-width: 0; }
.brand-text strong { font-family: "Outfit", sans-serif; font-size: 18px; letter-spacing: .5px; }
.brand-text small { color: var(--muted); font-size: 12px; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }

.topbar-actions { display: flex; align-items: center; gap: 8px; flex: none; }

.icon-btn {
  display: grid; place-items: center;
  width: 40px; height: 40px;
  border-radius: 12px;
  border: 1px solid var(--border);
  background: var(--surface);
  cursor: pointer;
  transition: border-color .2s, transform .1s;
}
.icon-btn:hover { border-color: var(--accent); }
.icon-btn:active { transform: scale(.96); }
:root[data-theme="dark"] .i-moon, :root:not([data-theme]) .i-moon { display: none; }
:root[data-theme="light"] .i-sun { display: none; }

.pill-toggle {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 8px 14px;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--surface);
  cursor: pointer;
  font-size: 14px;
  white-space: nowrap;
}
.pill-toggle:hover { border-color: var(--accent); }
.pill-dot {
  width: 30px; height: 18px; border-radius: 999px;
  background: var(--surface-3); position: relative; transition: background .2s;
}
.pill-dot::after {
  content: ""; position: absolute; top: 3px; left: 3px;
  width: 12px; height: 12px; border-radius: 50%;
  background: var(--muted); transition: transform .2s, background .2s;
}
.pill-toggle[aria-pressed="true"] .pill-dot { background: var(--accent); }
.pill-toggle[aria-pressed="true"] .pill-dot::after { transform: translateX(12px); background: var(--accent-ink); }

/* ---------- Disposición ---------- */
main {
  flex: 1;
  width: 100%;
  max-width: 1120px;
  margin: 0 auto;
  padding: 28px clamp(16px, 4vw, 40px) 60px;
  outline: none;
}

.footer {
  text-align: center;
  padding: 24px 16px 32px;
  border-top: 1px solid var(--border);
  color: var(--muted);
  font-size: 14px;
}
.footer p { margin: 2px 0; }

/* ---------- Portada ---------- */
.hero { padding: 24px 0 8px; }
.hero h1 { font-size: clamp(30px, 5vw, 48px); letter-spacing: -.5px; }
.hero h1 em { font-style: normal; color: var(--accent); }
.hero .lead { font-size: 18px; color: var(--muted); max-width: 680px; margin: 0; }
.hero .lead-th { font-size: 16px; color: var(--muted); margin: 4px 0 0; }

.stats { display: flex; flex-wrap: wrap; gap: 10px; margin: 20px 0 8px; }
.stat {
  padding: 10px 16px; border-radius: 14px;
  background: var(--surface); border: 1px solid var(--border);
  font-size: 14px; color: var(--muted);
}
.stat b { color: var(--text); font-size: 18px; margin-right: 4px; }

.levels { display: grid; grid-template-columns: repeat(auto-fit, minmax(150px, 1fr)); gap: 12px; margin: 28px 0 10px; }
.level-card {
  text-align: left; cursor: pointer;
  padding: 16px; border-radius: 16px;
  background: var(--surface); border: 1px solid var(--border);
  transition: border-color .2s, transform .15s;
}
.level-card:hover { transform: translateY(-2px); border-color: var(--accent); }
.level-card.active { border-color: var(--accent); box-shadow: inset 0 0 0 1px var(--accent); }
.level-card .lv { font: 800 26px/1 "Outfit", sans-serif; color: var(--accent); }
.level-card .lv-name { display: block; font-weight: 600; margin-top: 6px; }
.level-card .lv-th { display: block; font-size: 13px; color: var(--muted); }
.progress { height: 6px; border-radius: 99px; background: var(--surface-3); margin-top: 12px; overflow: hidden; }
.progress > i { display: block; height: 100%; background: var(--accent); border-radius: 99px; transition: width .4s; }
.level-card .lv-count { font-size: 12px; color: var(--muted); margin-top: 6px; display: block; }

.filters { display: flex; flex-wrap: wrap; align-items: center; gap: 8px; margin: 18px 0; }
.chip {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 7px 14px; border-radius: 999px;
  border: 1px solid var(--border); background: var(--surface);
  cursor: pointer; font-size: 14px;
}
.chip:hover { border-color: var(--cat, var(--accent)); }
.chip.active { background: var(--cat, var(--accent)); border-color: var(--cat, var(--accent)); color: var(--bg); font-weight: 600; }
.chip .dot { width: 8px; height: 8px; border-radius: 50%; background: var(--cat, var(--accent)); }
.chip.active .dot { background: var(--bg); }

.search {
  flex: 1 1 220px;
  min-width: 0;
  padding: 9px 14px; border-radius: 999px;
  border: 1px solid var(--border); background: var(--surface); color: var(--text);
  font: inherit; font-size: 14px;
}
.search:focus { outline: none; border-color: var(--accent); }

.section-title { display: flex; align-items: baseline; gap: 10px; margin: 30px 0 12px; }
.section-title h2 { margin: 0; font-size: 22px; }
.section-title .badge { font: 700 13px/1 "Outfit", sans-serif; padding: 5px 9px; border-radius: 8px; background: var(--accent); color: var(--accent-ink); }

.grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(260px, 1fr)); gap: 14px; }

.lesson-card {
  position: relative;
  display: flex; flex-direction: column; gap: 8px;
  padding: 18px; border-radius: 18px;
  background: var(--surface); border: 1px solid var(--border);
  text-decoration: none; color: var(--text);
  transition: transform .15s, border-color .2s, box-shadow .2s;
  overflow: hidden;
}
.lesson-card::before {
  content: ""; position: absolute; inset: 0 auto 0 0; width: 4px; background: var(--cat);
}
.lesson-card:hover { transform: translateY(-3px); border-color: var(--cat); box-shadow: var(--shadow); }
.lesson-card h3 { font-size: 18px; margin: 0; }
.lesson-card .th { font-size: 14px; color: var(--muted); margin: 0; }
.lesson-card .summary { font-size: 14px; color: var(--muted); margin: 0; }
.lesson-card .meta { display: flex; align-items: center; justify-content: space-between; gap: 8px; margin-top: auto; padding-top: 6px; font-size: 13px; color: var(--muted); }
.done-badge { color: var(--ok); font-weight: 600; }

.tag {
  display: inline-flex; align-items: center; gap: 6px;
  font-size: 12px; font-weight: 600; letter-spacing: .3px;
  padding: 3px 9px; border-radius: 999px;
  color: var(--cat); background: color-mix(in srgb, var(--cat) 14%, transparent);
  width: fit-content;
}
.tag.level { --cat: var(--accent); }
.tags { display: flex; gap: 6px; flex-wrap: wrap; }

.empty { padding: 40px; text-align: center; color: var(--muted); border: 1px dashed var(--border); border-radius: 18px; }

/* ---------- Lección ---------- */
.crumbs { font-size: 14px; color: var(--muted); margin-bottom: 14px; display: flex; gap: 6px; flex-wrap: wrap; align-items: center; }
.crumbs a { color: var(--muted); text-decoration: none; }
.crumbs a:hover { color: var(--accent); }

.lesson-head {
  padding: 24px; border-radius: 22px;
  background: linear-gradient(135deg, color-mix(in srgb, var(--cat) 16%, var(--surface)), var(--surface));
  border: 1px solid var(--border);
  margin-bottom: 20px;
}
.lesson-head h1 { font-size: clamp(26px, 4vw, 36px); margin: 10px 0 4px; }
.lesson-head .title-th { font-size: 18px; color: var(--muted); margin: 0 0 10px; }
.lesson-head p.es { margin: 0; font-size: 17px; }

.panel {
  padding: 22px; border-radius: 20px;
  background: var(--surface); border: 1px solid var(--border);
  margin-bottom: 18px;
}
.panel-head { display: flex; align-items: center; justify-content: space-between; gap: 12px; margin-bottom: 12px; flex-wrap: wrap; }
.panel-head h2 { margin: 0; font-size: 20px; }

.block { margin: 0 0 22px; }
.block:last-child { margin-bottom: 0; }
.block h3 { font-size: 18px; color: var(--cat); margin-bottom: 8px; }
.block p { margin: 0 0 6px; }

/* Texto en tailandés: oculto salvo que el contenedor tenga .show-th */
.th { display: none; }
.show-th .th { display: block; }
.show-th span.th { display: inline; }
p.th, div.th {
  margin: 4px 0 10px;
  padding: 8px 12px;
  border-left: 3px solid var(--th-border);
  background: var(--th-bg);
  border-radius: 0 10px 10px 0;
  color: var(--text);
}
.lesson-card .th, .lesson-head .title-th, .opt .th, td .th { padding: 0; border: 0; background: none; }
/* Algunos textos en tailandés se muestran siempre (títulos, etiquetas) */
.th.always { display: block; }
span.th.always { display: inline; }

.th-toggle {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 6px 12px; border-radius: 999px;
  border: 1px solid var(--th-border); background: var(--th-bg);
  cursor: pointer; font-size: 13px; white-space: nowrap;
}
.th-toggle:hover { border-color: var(--accent); }
.th-toggle[aria-pressed="true"] { background: var(--accent); color: var(--accent-ink); border-color: var(--accent); }

table { width: 100%; border-collapse: collapse; margin: 8px 0; font-size: 15px; }
.table-wrap { overflow-x: auto; border: 1px solid var(--border); border-radius: 14px; }
.table-wrap table { margin: 0; }
th, td { padding: 9px 12px; text-align: left; border-bottom: 1px solid var(--border); vertical-align: top; }
thead th { background: var(--surface-2); font-family: "Outfit", "Noto Sans Thai", sans-serif; font-weight: 600; }
tbody tr:last-child td { border-bottom: 0; }
td .th { font-size: 13px; color: var(--muted); }

.examples { list-style: none; margin: 0; padding: 0; display: grid; gap: 8px; }
.examples li {
  display: flex; gap: 10px; align-items: flex-start;
  padding: 10px 12px; border-radius: 12px; background: var(--surface-2);
}
.examples li > div { flex: 1; min-width: 0; }
.examples .es { margin: 0; font-weight: 500; }
.examples .th { margin: 4px 0 0; }

.say-btn {
  flex: none; display: grid; place-items: center;
  width: 32px; height: 32px; border-radius: 10px;
  border: 1px solid var(--border); background: var(--surface);
  cursor: pointer; color: var(--accent);
}
.say-btn:hover { border-color: var(--accent); }
.say-btn svg { width: 16px; height: 16px; }

.tip {
  display: flex; gap: 12px;
  padding: 16px; border-radius: 16px;
  background: color-mix(in srgb, var(--accent) 10%, var(--surface));
  border: 1px solid color-mix(in srgb, var(--accent) 40%, var(--border));
}
.tip .tip-icon { font-size: 22px; line-height: 1; }
.tip h3 { color: var(--accent) !important; margin-bottom: 4px; }

.vocab { display: grid; grid-template-columns: repeat(auto-fill, minmax(200px, 1fr)); gap: 8px; }
.vocab div { padding: 8px 12px; border-radius: 10px; background: var(--surface-2); }
.vocab b { display: block; }
.vocab span { color: var(--muted); font-size: 14px; }

.words { display: grid; grid-template-columns: repeat(auto-fill, minmax(230px, 1fr)); gap: 8px; }
.word-card { display: flex; gap: 10px; align-items: flex-start; padding: 10px 12px; border-radius: 12px; background: var(--surface-2); }
.word-card > div { display: flex; flex-direction: column; min-width: 0; }
.w-es { font-size: 16px; }
.w-pron { color: var(--cat); font-size: 15px; }
.w-pron b { text-decoration: underline; text-underline-offset: 3px; }
.w-th { color: var(--muted); font-size: 14px; }

.reading p.es { font-size: 17px; line-height: 1.8; }
.reading .para { margin-bottom: 12px; }

.audio-box { padding: 16px; border-radius: 16px; background: var(--surface-2); }
.audio-controls { display: flex; flex-wrap: wrap; gap: 8px; align-items: center; }
.transcript { margin-top: 14px; display: none; }
.transcript.open { display: block; }
.line { margin-bottom: 10px; }
.line .who { font-weight: 700; color: var(--cat); margin-right: 6px; }
.line .th { margin-left: 0; }

.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  padding: 9px 16px; border-radius: 12px;
  border: 1px solid var(--border); background: var(--surface);
  cursor: pointer; font-weight: 600; font-size: 14px; text-decoration: none; color: var(--text);
}
.btn:hover { border-color: var(--accent); }
.btn.primary { background: var(--accent); border-color: var(--accent); color: var(--accent-ink); }
.btn.primary:hover { filter: brightness(1.05); }
.btn:disabled { opacity: .5; cursor: not-allowed; }

/* ---------- Actividades ---------- */
.activity {
  padding: 18px; border-radius: 16px;
  background: var(--surface-2); border: 1px solid var(--border);
  margin-bottom: 14px;
}
.activity.correct { border-color: var(--ok); }
.activity.wrong { border-color: var(--bad); }
.act-head { display: flex; justify-content: space-between; align-items: flex-start; gap: 10px; margin-bottom: 10px; }
.act-num { font: 700 13px/1 "Outfit", sans-serif; color: var(--muted); text-transform: uppercase; letter-spacing: .6px; }
.act-q { font-size: 17px; font-weight: 500; margin: 6px 0 0; }
.act-q + .th { margin-top: 6px; }

.options { display: grid; gap: 8px; margin-top: 12px; }
.opt {
  text-align: left; cursor: pointer;
  padding: 10px 14px; border-radius: 12px;
  border: 1px solid var(--border); background: var(--surface);
  transition: border-color .15s;
}
.opt:hover:not(:disabled) { border-color: var(--accent); }
.opt:disabled { cursor: default; }
.opt.is-correct { border-color: var(--ok); background: var(--ok-bg); }
.opt.is-wrong { border-color: var(--bad); background: var(--bad-bg); }
.opt .th { font-size: 14px; color: var(--muted); }
.options.tf { grid-template-columns: 1fr 1fr; }

.fill-row { display: flex; gap: 8px; flex-wrap: wrap; margin-top: 12px; }
.fill-row input {
  flex: 1 1 200px; min-width: 0;
  padding: 10px 14px; border-radius: 12px;
  border: 1px solid var(--border); background: var(--surface); color: var(--text);
  font: inherit;
}
.fill-row input:focus { outline: none; border-color: var(--accent); }
.fill-row input.ok { border-color: var(--ok); }
.fill-row input.no { border-color: var(--bad); }

.accent-keys { display: flex; gap: 4px; flex-wrap: wrap; margin-top: 8px; }
.accent-keys button {
  width: 32px; height: 32px; border-radius: 8px;
  border: 1px solid var(--border); background: var(--surface); cursor: pointer;
}
.accent-keys button:hover { border-color: var(--accent); }

.order-target, .order-pool {
  display: flex; flex-wrap: wrap; gap: 8px;
  min-height: 50px; padding: 10px; border-radius: 12px; margin-top: 10px;
}
.order-target { border: 1px dashed var(--border); background: var(--surface); }
.word {
  padding: 7px 12px; border-radius: 10px;
  border: 1px solid var(--border); background: var(--surface-3);
  cursor: pointer; font-weight: 500;
}
.word:hover { border-color: var(--accent); }

.feedback { margin-top: 12px; padding: 10px 14px; border-radius: 12px; display: none; }
.feedback.show { display: block; }
.feedback.ok { background: var(--ok-bg); color: var(--ok); }
.feedback.no { background: var(--bad-bg); color: var(--bad); }
.feedback .x { color: var(--text); margin-top: 4px; }
.feedback .x p { margin: 0; }

.result {
  display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 12px;
  padding: 18px; border-radius: 16px;
  background: color-mix(in srgb, var(--accent) 12%, var(--surface));
  border: 1px solid var(--accent);
}
.result strong { font: 700 22px/1.2 "Outfit", sans-serif; }

.lesson-nav { display: flex; justify-content: space-between; gap: 12px; flex-wrap: wrap; margin-top: 24px; }
.lesson-nav a { max-width: 48%; }

@media (max-width: 640px) {
  .brand-text small { display: none; }
  .pill-toggle > span:last-child { font-size: 13px; }
  .panel, .lesson-head { padding: 16px; border-radius: 16px; }
  .options.tf { grid-template-columns: 1fr; }
  .lesson-nav a { max-width: 100%; flex: 1 1 100%; }
}

@media (prefers-reduced-motion: reduce) {
  * { transition: none !important; }
}