/* ==========================================================
   Curso de HTML · estilos compartidos
   ========================================================== */
:root {
  --bg: #f7f8fc;
  --surface: #ffffff;
  --surface-2: #eef1f8;
  --text: #1e2235;
  --muted: #5b6280;
  --border: #dde2ef;
  --accent: #4f46e5;
  --accent-soft: #e8e7fd;
  --accent-text: #ffffff;
  --code-bg: #14172b;
  --code-text: #e6e9f5;
  --nota: #0ea5e9;
  --importante: #e11d48;
  --consejo: #16a34a;
  --ejemplo: #d97706;
  --nota-t: #035985;
  --importante-t: #b4103a;
  --consejo-t: #166534;
  --ejemplo-t: #8a3b0c;
  --radius: 14px;
  --shadow: 0 1px 2px rgba(20, 23, 43, .06), 0 8px 24px rgba(20, 23, 43, .06);
  --font: "Inter", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  --mono: ui-monospace, "SF Mono", "Cascadia Code", Consolas, monospace;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #0f1222; --surface: #181c33; --surface-2: #1f2440; --text: #e8eaf6;
    --muted: #9aa1c4; --border: #2b3158; --accent: #a5a2ff; --accent-soft: #272b57; --nota-t: #7dd3fc; --importante-t: #fda4af; --consejo-t: #86efac; --ejemplo-t: #fcd34d;
    --accent-text: #0f1222; --code-bg: #0a0c19; --shadow: 0 8px 24px rgba(0, 0, 0, .35);
  }
}
:root[data-theme="dark"] {
  --bg: #0f1222; --surface: #181c33; --surface-2: #1f2440; --text: #e8eaf6;
  --muted: #9aa1c4; --border: #2b3158; --accent: #a5a2ff; --accent-soft: #272b57; --nota-t: #7dd3fc; --importante-t: #fda4af; --consejo-t: #86efac; --ejemplo-t: #fcd34d;
  --accent-text: #0f1222; --code-bg: #0a0c19; --shadow: 0 8px 24px rgba(0, 0, 0, .35);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 5rem; }
body {
  margin: 0; background: var(--bg); color: var(--text);
  font-family: var(--font); font-size: 1.05rem; line-height: 1.75;
}
img { max-width: 100%; }
a { color: var(--accent); text-underline-offset: 3px; }
a:hover { text-decoration-thickness: 2px; }
:focus-visible { outline: 3px solid var(--accent); outline-offset: 2px; border-radius: 4px; }

/* ---------- Barra superior ---------- */
.topbar {
  position: sticky; top: 0; z-index: 10; display: flex; align-items: center;
  justify-content: space-between; gap: 1rem; padding: .7rem 1.25rem;
  background: color-mix(in srgb, var(--surface) 88%, transparent);
  backdrop-filter: blur(10px); border-bottom: 1px solid var(--border);
}
.brand { display: flex; align-items: center; gap: .6rem; font-weight: 700; color: var(--text); text-decoration: none; }
.brand-logo {
  display: grid; place-items: center; width: 2rem; height: 2rem; border-radius: 9px;
  background: var(--accent); color: var(--accent-text); font-family: var(--mono); font-size: .9rem;
}
.topbar-actions { display: flex; align-items: center; gap: .5rem; }
.icon-btn {
  border: 1px solid var(--border); background: var(--surface); color: var(--text);
  border-radius: 10px; padding: .4rem .75rem; font: inherit; font-size: .9rem; cursor: pointer;
}
.icon-btn:hover { background: var(--surface-2); }

/* ---------- Contenedores ---------- */
.wrap { max-width: 1080px; margin: 0 auto; padding: 0 1.25rem; }
.hero { padding: 4rem 0 2.5rem; text-align: center; }
.hero .eyebrow {
  display: inline-block; padding: .3rem .85rem; border-radius: 999px; font-size: .85rem;
  font-weight: 600; background: var(--accent-soft); color: var(--accent);
}
.hero h1 { font-size: clamp(2.1rem, 5vw, 3.4rem); line-height: 1.15; margin: 1rem 0 .75rem; letter-spacing: -.02em; }
.hero p { max-width: 640px; margin: 0 auto 1.75rem; color: var(--muted); font-size: 1.15rem; }
.btn {
  display: inline-block; padding: .8rem 1.5rem; border-radius: 12px; font-weight: 600;
  background: var(--accent); color: var(--accent-text); text-decoration: none; border: 0;
  font-family: inherit; font-size: 1rem; cursor: pointer; transition: transform .15s;
}
.btn:hover { transform: translateY(-2px); }
.btn.secondary { background: var(--surface); color: var(--text); border: 1px solid var(--border); margin-left: .5rem; }

.features { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 1rem; margin: 1rem 0 3rem; }
.feature { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 1.25rem; box-shadow: var(--shadow); }
.feature .emoji { font-size: 1.7rem; }
.feature h2, .feature h3 { margin: .4rem 0 .2rem; font-size: 1.05rem; }
.feature p { margin: 0; color: var(--muted); font-size: .95rem; line-height: 1.55; }

h2.section-title { font-size: 1.7rem; margin: 2.5rem 0 1rem; letter-spacing: -.01em; }

/* ---------- Tarjetas de lecciones ---------- */
.lessons { display: grid; grid-template-columns: repeat(auto-fill, minmax(290px, 1fr)); gap: 1rem; padding: 0; list-style: none; margin: 0 0 3rem; }
.lesson-card {
  position: relative; display: flex; flex-direction: column; height: 100%; padding: 1.25rem;
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
  box-shadow: var(--shadow); color: inherit; text-decoration: none; transition: transform .15s, border-color .15s;
}
a.lesson-card:hover { transform: translateY(-3px); border-color: var(--accent); }
.lesson-num { font-family: var(--mono); font-size: .85rem; color: var(--accent); font-weight: 700; }
.lesson-card h3 { margin: .25rem 0 .4rem; font-size: 1.15rem; }
.lesson-card p { margin: 0 0 1rem; color: var(--muted); font-size: .95rem; line-height: 1.55; flex: 1; }
.tag { align-self: flex-start; padding: .15rem .7rem; border-radius: 999px; font-size: .78rem; font-weight: 600; }
.tag.open { background: #dcfce7; color: #166534; }
.tag.soon { background: var(--surface-2); color: var(--muted); }
@media (prefers-color-scheme: dark) { :root:not([data-theme="light"]) .tag.open { background: #14391f; color: #86efac; } }
:root[data-theme="dark"] .tag.open { background: #14391f; color: #86efac; }
.lesson-card.disabled { opacity: .65; }

/* ---------- Lección: diseño en dos columnas ---------- */
.lesson-layout { display: grid; grid-template-columns: 250px minmax(0, 1fr); gap: 3rem; padding-top: 2rem; padding-bottom: 3rem; }
.toc { position: sticky; top: 5rem; align-self: start; font-size: .92rem; }
.toc h4 { margin: 0 0 .6rem; font-size: .8rem; text-transform: uppercase; letter-spacing: .08em; color: var(--muted); }
.toc ol { list-style: none; margin: 0; padding: 0; border-left: 2px solid var(--border); }
.toc a { display: block; padding: .3rem 0 .3rem 1rem; margin-left: -2px; border-left: 2px solid transparent; color: var(--muted); text-decoration: none; line-height: 1.4; }
.toc a:hover, .toc a.active { color: var(--accent); border-left-color: var(--accent); }
@media (max-width: 860px) { .lesson-layout { grid-template-columns: 1fr; gap: 1rem; } .toc { display: none; } }

.lesson-head { margin-bottom: 1.5rem; }
.breadcrumb { font-size: .9rem; color: var(--muted); }
.breadcrumb a { color: var(--muted); }
.lesson-head h1 { font-size: clamp(1.9rem, 4vw, 2.7rem); line-height: 1.2; margin: .4rem 0 .6rem; letter-spacing: -.02em; }
.meta { display: flex; flex-wrap: wrap; gap: .5rem; padding: 0; margin: 0; list-style: none; }
.meta li { padding: .25rem .75rem; border-radius: 999px; background: var(--surface-2); font-size: .85rem; color: var(--muted); }

article h2 { font-size: 1.6rem; margin: 2.75rem 0 .75rem; letter-spacing: -.01em; }
article h2 .n { color: var(--accent); font-family: var(--mono); margin-right: .4rem; }
article h3 { font-size: 1.2rem; margin: 1.75rem 0 .5rem; }
article p, article li { max-width: 70ch; }
article ul, article ol { padding-left: 1.4rem; }
article li { margin: .3rem 0; }
code {
  font-family: var(--mono); font-size: .9em; padding: .12em .4em; border-radius: 6px;
  background: var(--accent-soft); color: var(--accent);
}
kbd {
  font-family: var(--mono); font-size: .85em; padding: .1em .45em; border-radius: 6px;
  border: 1px solid var(--border); border-bottom-width: 3px; background: var(--surface);
}

/* ---------- Bloques de código ---------- */
.code { margin: 1.25rem 0; border-radius: var(--radius); overflow: hidden; background: var(--code-bg); box-shadow: var(--shadow); }
.code-head { display: flex; justify-content: space-between; align-items: center; padding: .5rem .5rem .5rem 1rem; background: rgba(255, 255, 255, .06); color: #a9b0d6; font-family: var(--mono); font-size: .8rem; }
.copy { border: 0; border-radius: 8px; padding: .25rem .7rem; font: inherit; background: rgba(255, 255, 255, .1); color: #e6e9f5; cursor: pointer; }
.copy:hover { background: rgba(255, 255, 255, .2); }
.code pre { margin: 0; padding: 1rem 1.25rem; overflow-x: auto; }
.code pre code { background: none; color: var(--code-text); padding: 0; font-size: .92rem; line-height: 1.7; }
.tk-tag { color: #ff8fa3; } .tk-attr { color: #ffd479; } .tk-val { color: #8ee6a0; } .tk-com { color: #7c84ad; font-style: italic; }

/* ---------- Recuadros (apuntes) ---------- */
.callout { --c: var(--nota); --ct: var(--nota-t); margin: 1.5rem 0; padding: 1rem 1.25rem 1rem 1.25rem; border-radius: var(--radius); border: 1px solid color-mix(in srgb, var(--c) 35%, var(--border)); border-left: 6px solid var(--c); background: color-mix(in srgb, var(--c) 9%, var(--surface)); }
.callout > :last-child { margin-bottom: 0; }
.callout-title { display: flex; align-items: center; gap: .5rem; margin: 0 0 .35rem; font-weight: 700; color: var(--ct); }
.callout p { margin: .3rem 0; }
.callout.importante { --c: var(--importante); --ct: var(--importante-t); }
.callout.consejo { --c: var(--consejo); --ct: var(--consejo-t); }
.callout.ejemplo { --c: var(--ejemplo); --ct: var(--ejemplo-t); }

/* ---------- Tablas ---------- */
.table-wrap { overflow-x: auto; margin: 1.25rem 0; border: 1px solid var(--border); border-radius: var(--radius); background: var(--surface); }
table { width: 100%; border-collapse: collapse; font-size: .95rem; }
th, td { text-align: left; padding: .75rem 1rem; border-bottom: 1px solid var(--border); vertical-align: top; }
th { background: var(--surface-2); font-size: .85rem; text-transform: uppercase; letter-spacing: .04em; color: var(--muted); }
tr:last-child td { border-bottom: 0; }

/* ---------- Diagrama de anatomía ---------- */
.anatomy { display: flex; flex-wrap: wrap; justify-content: center; align-items: flex-end; gap: .25rem; padding: 2rem 1rem 1.25rem; margin: 1.5rem 0; border-radius: var(--radius); background: var(--code-bg); font-family: var(--mono); font-size: clamp(.85rem, 2.6vw, 1.15rem); color: var(--code-text); box-shadow: var(--shadow); }
.anatomy .part { display: flex; flex-direction: column; align-items: center; }
.anatomy .part span.lbl { margin-top: .6rem; padding-top: .35rem; border-top: 2px solid var(--c); font-family: var(--font); font-size: .75rem; color: var(--c); }

/* ---------- Apuntes para llevar ---------- */
.apuntes { margin: 2.5rem 0; padding: 1.5rem 1.75rem; border-radius: var(--radius); background: var(--accent-soft); border: 1px dashed var(--accent); }
.apuntes h2 { margin-top: 0 !important; }
.apuntes ul { list-style: none; padding: 0; }
.apuntes li::before { content: "✓"; margin-right: .6rem; color: var(--accent); font-weight: 700; }

/* ---------- Checklist y detalles ---------- */
.checklist { list-style: none; padding: 0 !important; }
.checklist label { display: flex; gap: .7rem; align-items: flex-start; padding: .65rem .9rem; border: 1px solid var(--border); border-radius: 12px; background: var(--surface); cursor: pointer; }
.checklist input { margin-top: .45rem; width: 1.1rem; height: 1.1rem; accent-color: var(--accent); }
.checklist input:checked + span { text-decoration: line-through; color: var(--muted); }
details { margin: 1rem 0; border: 1px solid var(--border); border-radius: 12px; background: var(--surface); }
summary { padding: .8rem 1.1rem; font-weight: 600; cursor: pointer; }
details[open] summary { border-bottom: 1px solid var(--border); }
details > :not(summary) { margin-left: 1.1rem; margin-right: 1.1rem; }
details > .code { margin-bottom: 1.1rem; }

/* ---------- Navegación entre lecciones ---------- */
.pager { display: flex; justify-content: space-between; gap: 1rem; margin-top: 3rem; flex-wrap: wrap; }
.pager a { flex: 1 1 220px; padding: 1rem 1.25rem; border: 1px solid var(--border); border-radius: var(--radius); background: var(--surface); color: var(--text); text-decoration: none; box-shadow: var(--shadow); }
.pager a:hover { border-color: var(--accent); }
.pager small { display: block; color: var(--muted); }
.pager .next { text-align: right; }

.site-footer { padding: 2rem 1.25rem; text-align: center; color: var(--muted); font-size: .9rem; border-top: 1px solid var(--border); }

/* Barra de progreso */
.progress { height: 10px; border-radius: 999px; background: var(--surface-2); overflow: hidden; margin: .5rem 0 0; }
.progress > div { height: 100%; width: 0; background: var(--accent); transition: width .3s; }

@media (prefers-reduced-motion: reduce) { * { transition: none !important; scroll-behavior: auto !important; } }
@media print { .topbar, .toc, .pager, .copy { display: none !important; } .lesson-layout { display: block; } }

/* ==========================================================
   Animaciones y componentes interactivos
   ========================================================== */
.tk-sel { color: #7cc4ff; }

/* Barra de lectura */
.read-progress { position: fixed; top: 0; left: 0; z-index: 30; height: 3px; width: 0; background: linear-gradient(90deg, var(--accent), #22d3ee); transition: width .1s linear; }

/* Aparición al hacer scroll (solo si JS activó la clase .js) */
.js .reveal { opacity: 0; transform: translateY(18px); transition: opacity .6s ease, transform .6s ease; }
.js .reveal.in { opacity: 1; transform: none; }

/* Entrada escalonada de tarjetas */
@keyframes rise { from { opacity: 0; transform: translateY(16px); } to { opacity: 1; transform: none; } }
.lessons > li, .features > .feature { animation: rise .55s ease both; }
.lessons > li:nth-child(1), .features > .feature:nth-child(1) { animation-delay: .05s; }
.lessons > li:nth-child(2), .features > .feature:nth-child(2) { animation-delay: .12s; }
.lessons > li:nth-child(3), .features > .feature:nth-child(3) { animation-delay: .19s; }
.lessons > li:nth-child(4), .features > .feature:nth-child(4) { animation-delay: .26s; }
.lessons > li:nth-child(n+5) { animation-delay: .33s; }
.feature { transition: transform .2s, border-color .2s; }
.feature:hover { transform: translateY(-4px); border-color: var(--accent); }
.feature .emoji { display: inline-block; transition: transform .3s; }
.feature:hover .emoji { transform: rotate(-10deg) scale(1.2); }

/* Hero con ventana de código que se escribe sola */
.hero-grid { display: grid; grid-template-columns: minmax(0, 1.1fr) minmax(0, 1fr); gap: 2.5rem; align-items: center; padding: 3.5rem 0 2.5rem; }
.hero-grid .hero { padding: 0; text-align: left; }
.hero-grid .hero p { margin-left: 0; }
.hero-demo { border-radius: var(--radius); overflow: hidden; background: var(--code-bg); box-shadow: 0 20px 50px rgba(79, 70, 229, .25); animation: float 6s ease-in-out infinite; }
@keyframes float { 0%, 100% { transform: translateY(0); } 50% { transform: translateY(-8px); } }
.win-bar { display: flex; gap: .4rem; padding: .6rem .9rem; background: rgba(255, 255, 255, .06); }
.win-bar i { width: .7rem; height: .7rem; border-radius: 50%; background: #ff5f57; }
.win-bar i:nth-child(2) { background: #febc2e; } .win-bar i:nth-child(3) { background: #28c840; }
.hero-demo pre { margin: 0; padding: 1rem 1.25rem; min-height: 8.5rem; color: var(--code-text); font-family: var(--mono); font-size: .88rem; line-height: 1.7; overflow-x: auto; white-space: pre-wrap; }
.hero-demo .caret::after { content: "▍"; color: var(--accent); animation: blink 1s steps(1) infinite; }
@keyframes blink { 50% { opacity: 0; } }
.hero-out { padding: 1rem 1.25rem; background: #fff; color: #1e2235; min-height: 7rem; font-family: system-ui, sans-serif; line-height: 1.5; }
.hero-out h1 { font-size: 1.5rem; margin: 0 0 .3rem; } .hero-out p { margin: 0 0 .4rem; }
.hero-out > * { animation: rise .4s ease both; }
@media (max-width: 860px) { .hero-grid { grid-template-columns: 1fr; } .hero-grid .hero { text-align: center; } .hero-grid .hero p { margin-inline: auto; } }

/* Diagrama de anatomía animado */
.anatomy.in .part { animation: pop .5s cubic-bezier(.2, 1.4, .4, 1) both; animation-delay: calc(var(--i, 0) * .14s); }
@keyframes pop { from { opacity: 0; transform: translateY(14px) scale(.85); } to { opacity: 1; transform: none; } }

/* Callouts y código con microinteracciones */
.callout { transition: transform .2s, box-shadow .2s; }
.callout:hover { transform: translateX(3px); box-shadow: var(--shadow); }
.code { transition: transform .2s; } .code:hover { transform: translateY(-2px); }
.lesson-card .lesson-num::after { content: ""; display: block; width: 0; height: 2px; margin-top: .2rem; background: var(--accent); transition: width .3s; }
a.lesson-card:hover .lesson-num::after { width: 3rem; }
.lesson-card.done { border-color: var(--consejo); }
.tag.done { background: #dcfce7; color: #166534; }
:root[data-theme="dark"] .tag.done { background: #14391f; color: #86efac; }
@media (prefers-color-scheme: dark) { :root:not([data-theme="light"]) .tag.done { background: #14391f; color: #86efac; } }
.avance { margin: 1.25rem auto 0; max-width: 360px; font-size: .9rem; color: var(--muted); }

/* Zona de práctica en vivo */
.playground { margin: 1.5rem 0; border: 1px solid var(--border); border-radius: var(--radius); background: var(--surface); box-shadow: var(--shadow); overflow: hidden; }
.pg-head { display: flex; justify-content: space-between; align-items: center; gap: .75rem; flex-wrap: wrap; padding: .6rem 1rem; background: var(--accent-soft); color: var(--accent); font-weight: 700; font-size: .95rem; }
.pg-head button { border: 1px solid var(--accent); background: transparent; color: var(--accent); border-radius: 8px; padding: .2rem .7rem; font: inherit; font-size: .85rem; cursor: pointer; }
.pg-head button:hover { background: var(--accent); color: var(--accent-text); }
.pg-body { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); }
.pg-body label { display: block; padding: .35rem 1rem; font-size: .75rem; text-transform: uppercase; letter-spacing: .08em; color: var(--muted); background: var(--surface-2); }
.pg-code { display: block; width: 100%; height: 240px; resize: vertical; border: 0; border-radius: 0; padding: 1rem; background: var(--code-bg); color: var(--code-text); font-family: var(--mono); font-size: .9rem; line-height: 1.6; tab-size: 2; }
.pg-out { display: block; width: 100%; height: 240px; border: 0; background: #fff; }
@media (max-width: 700px) { .pg-body { grid-template-columns: 1fr; } }

/* Autoevaluación */
.quiz { margin: 2.5rem 0; padding: 1.5rem; border: 1px solid var(--border); border-radius: var(--radius); background: var(--surface); box-shadow: var(--shadow); }
.quiz > h2 { margin: 0 0 .25rem !important; }
.quiz-q { margin-top: 1.5rem; }
.quiz-q > p { margin: 0 0 .6rem; font-weight: 600; }
.opts { list-style: none; margin: 0; padding: 0 !important; display: grid; gap: .5rem; }
.opt { width: 100%; text-align: left; padding: .65rem .9rem; border: 1px solid var(--border); border-radius: 10px; background: var(--bg); color: var(--text); font: inherit; font-size: .98rem; cursor: pointer; transition: transform .15s, border-color .15s, background .15s; }
.opt:hover:not(:disabled) { border-color: var(--accent); transform: translateX(4px); }
.opt:disabled { cursor: default; }
.opt.ok { border-color: var(--consejo); background: color-mix(in srgb, var(--consejo) 14%, var(--surface)); animation: pop .4s both; }
.opt.bad { border-color: var(--importante); background: color-mix(in srgb, var(--importante) 12%, var(--surface)); animation: shake .4s; }
@keyframes shake { 20%, 60% { transform: translateX(-6px); } 40%, 80% { transform: translateX(6px); } }
.explain { margin: .6rem 0 0; padding: .6rem .9rem; border-radius: 10px; background: var(--surface-2); font-size: .95rem; animation: rise .35s both; }
.quiz-score { margin: 1.25rem 0 0; font-weight: 700; color: var(--accent); min-height: 1.5rem; }

/* Marcar lección */
.complete { display: flex; align-items: center; gap: 1rem; flex-wrap: wrap; margin: 2rem 0; padding: 1.25rem; border: 2px dashed var(--border); border-radius: var(--radius); }
.complete p { margin: 0; color: var(--muted); }
.complete .btn.done { background: var(--consejo); }
.js .complete .btn.done::before { content: "✓ "; }

/* Mapa de etiquetas / pasos visuales */
.steps { counter-reset: paso; list-style: none; padding: 0 !important; display: grid; gap: .75rem; }
.steps li { counter-increment: paso; position: relative; padding: .9rem 1rem .9rem 3.5rem; border: 1px solid var(--border); border-radius: 12px; background: var(--surface); }
.steps li::before { content: counter(paso); position: absolute; left: 1rem; top: .8rem; display: grid; place-items: center; width: 1.8rem; height: 1.8rem; border-radius: 50%; background: var(--accent); color: var(--accent-text); font-weight: 700; font-size: .9rem; }

/* Visualización de la caja (CSS) */
.boxmodel { display: grid; place-items: center; margin: 1.5rem 0; }
.bm { padding: 1.4rem; background: #fbbf77; color: #1e2235; text-align: center; font-size: .8rem; border-radius: 8px; }
.bm .bm-b { margin-top: 1.1rem; padding: 1.1rem; background: #f59e0b; border-radius: 6px; }
.bm .bm-p { margin-top: 1.1rem; padding: 1.1rem; background: #a5b4fc; border-radius: 6px; }
.bm .bm-c { margin-top: 1.1rem; padding: .9rem 2rem; background: #4f46e5; color: #fff; border-radius: 4px; font-weight: 700; }
.bm span.t { display: block; font-weight: 700; }

@media (prefers-reduced-motion: reduce) {
  .hero-demo, .lessons > li, .features > .feature, .anatomy.in .part, .explain { animation: none !important; }
  .js .reveal { opacity: 1; transform: none; transition: none; }
}

/* Evita que código o tablas anchos ensanchen la página en pantallas pequeñas */
.lesson-layout > * { min-width: 0; }
@media (max-width: 860px) { .lesson-layout { grid-template-columns: minmax(0, 1fr); } }
.anatomy { overflow-x: auto; }
article :not(pre) > code { overflow-wrap: anywhere; }
.hero-grid .avance { margin-left: 0; }
@media (max-width: 860px) { .hero-grid .avance { margin-inline: auto; } }
@media print { .js .reveal { opacity: 1; transform: none; } }

/* Cuadros de demostración («Así se ve») */
.demo { margin: 1.25rem 0; padding: 1.25rem; border: 1px solid var(--border); border-radius: var(--radius); background: var(--surface); overflow-x: auto; }
.demo-label { margin: 0 0 .5rem; font-size: .8rem; text-transform: uppercase; letter-spacing: .08em; color: var(--muted); }
.demo img { border-radius: 10px; }
.demo figure { margin: 0; }
.demo figcaption { margin-top: .5rem; font-size: .9rem; color: var(--muted); }
.table-wrap td:first-child code, .table-wrap th code { white-space: nowrap; overflow-wrap: normal; }

/* Comprobador de ejercicios */
.checker { margin: 2rem 0; padding: 1.5rem; border: 1px solid var(--border); border-radius: var(--radius); background: var(--surface); box-shadow: var(--shadow); }
.checker h2 { margin: 0 0 .5rem !important; }
.checker label { display: block; margin: 1rem 0 .4rem; font-weight: 600; }
.checker textarea { display: block; width: 100%; min-height: 200px; resize: vertical; padding: .9rem; border: 1px solid var(--border); border-radius: 10px; background: var(--code-bg); color: var(--code-text); font-family: var(--mono); font-size: .9rem; line-height: 1.6; tab-size: 2; }
.chk-actions { display: flex; gap: .6rem; flex-wrap: wrap; margin: 1rem 0; }
.chk-sum { margin: 0 0 .75rem; font-weight: 700; min-height: 1.5rem; }
.chk-sum.all { color: var(--consejo-t); animation: pop .5s both; }
.chk-list { list-style: none; margin: 0; padding: 0 !important; display: grid; gap: .5rem; }
.chk-list li { display: grid; grid-template-columns: auto 1fr; gap: .1rem .7rem; align-items: start; padding: .6rem .9rem; border: 1px solid var(--border); border-radius: 10px; background: var(--bg); animation: rise .35s both; animation-delay: calc(var(--i, 0) * 40ms); }
.chk-list li::before { content: "✗"; grid-row: span 2; display: grid; place-items: center; width: 1.5rem; height: 1.5rem; border-radius: 50%; background: color-mix(in srgb, var(--importante) 18%, var(--surface)); color: var(--importante-t); font-weight: 700; font-size: .85rem; }
.chk-list li.ok { border-color: color-mix(in srgb, var(--consejo) 45%, var(--border)); }
.chk-list li.ok::before { content: "✓"; background: color-mix(in srgb, var(--consejo) 20%, var(--surface)); color: var(--consejo-t); }
.chk-list .hint { grid-column: 2; color: var(--muted); font-size: .9rem; }
.chk-list li.ok .hint { display: none; }
@media (prefers-reduced-motion: reduce) { .chk-list li, .chk-sum.all { animation: none !important; } }

/* Barra superior compacta en móvil */
@media (max-width: 520px) {
  .topbar { padding: .6rem .9rem; }
  .brand { white-space: nowrap; font-size: .95rem; }
  .topbar-actions a.icon-btn { display: none; }
}

/* Widgets interactivos (contraste, vista previa en buscadores, flujo) */
.widget { margin: 1.5rem 0; border: 1px solid var(--border); border-radius: var(--radius); background: var(--surface); box-shadow: var(--shadow); overflow: hidden; }
.w-head { padding: .6rem 1rem; background: var(--accent-soft); color: var(--accent); font-weight: 700; font-size: .95rem; }
.w-body { display: grid; gap: .9rem; padding: 1.1rem; }
.w-row { display: flex; flex-wrap: wrap; gap: 1rem; align-items: center; }
.w-row label { font-weight: 600; font-size: .92rem; }
.w-body input[type="color"] { width: 3rem; height: 2.2rem; padding: 0; border: 1px solid var(--border); border-radius: 8px; background: none; cursor: pointer; }
.w-body input[type="text"] { width: 100%; padding: .55rem .7rem; border: 1px solid var(--border); border-radius: 8px; background: var(--bg); color: var(--text); font: inherit; }
.c-sample { padding: 1.2rem; border-radius: 10px; border: 1px solid var(--border); font-size: 1.1rem; font-weight: 600; transition: background .2s, color .2s; }
.c-ratio { margin: 0; font-size: 1.6rem; font-weight: 800; letter-spacing: -.01em; }
.c-res { list-style: none; margin: 0; padding: 0 !important; display: flex; flex-wrap: wrap; gap: .5rem; }
.c-res li { padding: .3rem .75rem; border-radius: 999px; font-size: .85rem; font-weight: 600; margin: 0; }
.c-res li.ok { background: color-mix(in srgb, var(--consejo) 18%, var(--surface)); color: var(--consejo-t); }
.c-res li.bad { background: color-mix(in srgb, var(--importante) 14%, var(--surface)); color: var(--importante-t); }
.serp-prev { padding: 1rem 1.1rem; border-radius: 10px; background: #fff; color: #202124; font-family: Arial, sans-serif; }
.serp-url { font-size: .82rem; color: #4d5156; overflow-wrap: anywhere; }
.serp-title { margin: .2rem 0; font-size: 1.2rem; line-height: 1.3; color: #1a0dab; overflow-wrap: anywhere; }
.serp-desc { font-size: .88rem; line-height: 1.55; color: #4d5156; overflow-wrap: anywhere; }
.counter { margin: .25rem 0 0; font-size: .82rem; color: var(--muted); }
.counter.ok { color: var(--consejo-t); font-weight: 600; }
.counter.bad { color: var(--importante-t); font-weight: 600; }
.flow { display: flex; flex-wrap: wrap; align-items: stretch; gap: .5rem; margin: 1.5rem 0; }
.flow .node { flex: 1 1 140px; padding: .9rem 1rem; border: 1px solid var(--border); border-radius: 12px; background: var(--surface); text-align: center; box-shadow: var(--shadow); }
.flow .node strong { display: block; color: var(--accent); }
.flow .node span { font-size: .85rem; color: var(--muted); }
.flow .arrow { align-self: center; font-weight: 700; color: var(--accent); text-align: center; font-size: .8rem; line-height: 1.2; }
.flow .arrow code { display: block; margin-top: .15rem; }
.badprobe { border-left: 6px solid var(--importante); }
.flow { gap: .4rem; }
.flow .node { flex: 1 1 100px; padding: .75rem .6rem; }
.flow .arrow { flex: 0 0 auto; }
@media (max-width: 700px) {
  .flow { flex-direction: column; }
  .flow .arrow { transform: none; }
  .flow .arrow code { display: inline; margin-left: .4rem; }
}

/* Enlace para saltar al contenido (visible solo con el foco del teclado) */
.saltar { position: absolute; left: -999px; top: 0; z-index: 100; padding: .7rem 1.1rem; border-radius: 0 0 10px 0; background: var(--accent); color: var(--accent-text); font-weight: 700; text-decoration: none; }
.saltar:focus { left: 0; }

/* Tablas de demostración con fondo claro en línea */
.demo th { color: #1e2235; background: #eeeeff; }

/* ---------- Editor de JavaScript, anchos y GIFs ---------- */
.pg-actions { display: flex; gap: .4rem; flex-wrap: wrap; }
.pg-frame { background: #fff; min-height: 240px; display: flex; justify-content: center; align-items: flex-start; overflow: auto; }
.pg-frame .pg-out { width: 100%; height: 240px; transition: width .25s; }
.playground.stacked .pg-body { grid-template-columns: minmax(0, 1fr); }
.playground.stacked .pg-frame { background: repeating-conic-gradient(var(--surface-2) 0 25%, var(--surface) 0 50%) 0 0 / 20px 20px; padding: 0; }
.playground.stacked .pg-out { height: 340px; max-width: 100%; border: 1px solid var(--border); }
.pg-console { border-top: 1px solid var(--border); background: var(--code-bg); color: var(--code-text); }
.pg-console-head { display: flex; justify-content: space-between; align-items: center; padding: .35rem 1rem; background: rgba(255, 255, 255, .06); font-size: .75rem; text-transform: uppercase; letter-spacing: .08em; color: #a9b0d6; }
.pg-console-head button { border: 0; border-radius: 6px; padding: .15rem .6rem; background: rgba(255, 255, 255, .1); color: #e6e9f5; font: inherit; font-size: .75rem; cursor: pointer; }
.pg-log { min-height: 3.2rem; max-height: 220px; overflow: auto; padding: .6rem 1rem; font-family: var(--mono); font-size: .88rem; line-height: 1.6; white-space: pre-wrap; }
.pg-log:empty::before { content: "La salida de console.log aparece aquí."; color: #7c84ad; }
.pg-log > div::before { content: "› "; color: #7c84ad; }
.pg-log .log-error { color: #ff8fa3; } .pg-log .log-error::before { content: "✗ "; }
.pg-log .log-warn { color: #ffd479; } .pg-log .log-warn::before { content: "⚠ "; }
.gif-demo { margin: 1.5rem 0; }
.gif-btn { position: relative; display: block; width: 100%; max-width: 640px; padding: 0; border: 1px solid var(--border); border-radius: var(--radius); overflow: hidden; background: var(--surface); box-shadow: var(--shadow); cursor: pointer; }
.gif-btn img { display: block; width: 100%; height: auto; }
.gif-play { position: absolute; right: .8rem; bottom: .8rem; padding: .35rem .9rem; border-radius: 999px; background: rgba(15, 18, 34, .88); color: #fff; font-size: .85rem; font-weight: 700; }
.gif-btn:hover .gif-play { background: var(--accent); color: var(--accent-text); }
.gif-demo figcaption { margin-top: .5rem; font-size: .9rem; color: var(--muted); }
.topbar .nav-cursos { white-space: nowrap; }
@media (max-width: 700px) { .topbar .nav-cursos { display: none; } }
.site-footer a { color: inherit; }
.site-footer .foot-links { display: block; margin-top: .4rem; }

/* ---------- Biblioteca de cursos ---------- */
.courses { list-style: none; margin: 0 0 3rem; padding: 0; display: grid; grid-template-columns: repeat(auto-fit, minmax(min(100%, 440px), 1fr)); gap: 1rem; }
.courses > li { animation: rise .55s ease both; }
.course-card { display: flex; flex-direction: column; gap: .5rem; height: 100%; padding: 1.4rem; background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); box-shadow: var(--shadow); color: inherit; text-decoration: none; transition: transform .2s, border-color .2s; }
a.course-card:hover { transform: translateY(-4px); border-color: var(--accent); }
.course-level { font-size: .78rem; font-weight: 700; text-transform: uppercase; letter-spacing: .08em; color: var(--accent); }
.course-card h3 { margin: 0; font-size: 1.35rem; }
.course-card p { margin: 0; color: var(--muted); font-size: .96rem; line-height: 1.6; flex: 1; }
.course-meta { list-style: none; margin: .3rem 0; padding: 0; display: flex; flex-wrap: wrap; gap: .4rem; }
.course-meta li { margin: 0; padding: .2rem .65rem; border-radius: 999px; background: var(--surface-2); font-size: .8rem; color: var(--muted); }
.course-prog { font-size: .85rem; font-weight: 600; color: var(--muted); }
.course-card.started .course-prog { color: var(--accent); }
.route-intro { color: var(--muted); max-width: 70ch; }
.route { list-style: none; margin: 1.25rem 0 3rem; padding: 0; display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: .75rem; counter-reset: none; }
.route li { margin: 0; }
.route a, .route div { display: flex; flex-direction: column; gap: .15rem; height: 100%; padding: 1rem 1.1rem; border: 1px solid var(--border); border-radius: 12px; background: var(--surface); color: inherit; text-decoration: none; }
.route li.ok a:hover { border-color: var(--accent); }
.route li.soon div { border-style: dashed; background: transparent; }
.route-n { display: grid; place-items: center; width: 1.7rem; height: 1.7rem; margin-bottom: .3rem; border-radius: 50%; background: var(--accent); color: var(--accent-text); font-weight: 700; font-size: .85rem; }
.route li.soon .route-n { background: var(--surface-2); color: var(--muted); }
.route-s { font-size: .82rem; color: var(--muted); }
.course-card.disabled { border-style: dashed; box-shadow: none; background: transparent; }

/* Portada de curso: requisitos y resultados */
.two-col { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 2rem; margin: 1rem 0 2rem; }
.checks-list { list-style: none; margin: .5rem 0 0; padding: 0; display: grid; gap: .5rem; }
.checks-list li { position: relative; padding-left: 1.8rem; margin: 0; }
.checks-list li::before { content: "✓"; position: absolute; left: 0; top: .05rem; display: grid; place-items: center; width: 1.3rem; height: 1.3rem; border-radius: 50%; background: var(--accent-soft); color: var(--accent); font-weight: 700; font-size: .75rem; }
.hero-log { font-family: var(--mono); font-size: .92rem; padding: .15rem 0; color: #1e2235; }
.hero-log::before { content: "› "; color: #64748b; }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0, 0, 0, 0); white-space: nowrap; border: 0; }

/* ==========================================================
   UI v3 · aurora, brillo con el cursor, inclinación 3D,
   confeti, buscador (Ctrl+K), volver arriba y más
   (todo es aditivo y se desactiva con prefers-reduced-motion)
   ========================================================== */
:root { --accent-2: #22d3ee; --accent-3: #f472b6; --glow: rgba(79, 70, 229, .28); }
@media (prefers-color-scheme: dark) { :root:not([data-theme="light"]) { --glow: rgba(165, 162, 255, .22); } }
:root[data-theme="dark"] { --glow: rgba(165, 162, 255, .22); }

/* Aurora de fondo */
.aurora { position: fixed; inset: 0; z-index: -1; overflow: hidden; pointer-events: none; }
.aurora i { position: absolute; width: 46vmax; height: 46vmax; border-radius: 50%; filter: blur(70px); opacity: .32; animation: drift 22s ease-in-out infinite alternate; will-change: transform; }
.aurora i:nth-child(1) { left: -12vmax; top: -14vmax; background: var(--accent); }
.aurora i:nth-child(2) { right: -14vmax; top: 18vh; background: var(--accent-2); animation-duration: 28s; animation-delay: -6s; opacity: .22; }
.aurora i:nth-child(3) { left: 24vw; bottom: -22vmax; background: var(--accent-3); animation-duration: 34s; animation-delay: -12s; opacity: .16; }
@keyframes drift { to { transform: translate3d(8vw, 6vh, 0) scale(1.18) rotate(30deg); } }
@media (prefers-color-scheme: dark) { :root:not([data-theme="light"]) .aurora i { opacity: .2; } }
:root[data-theme="dark"] .aurora i { opacity: .2; }

/* Cuadrícula de puntos en el hero */
.hero-grid, section.hero { position: relative; }
.hero-grid::before, section.hero::before {
  content: ""; position: absolute; inset: 0; z-index: -1; pointer-events: none;
  background-image: radial-gradient(color-mix(in srgb, var(--accent) 28%, transparent) 1px, transparent 1.4px);
  background-size: 26px 26px;
  -webkit-mask-image: radial-gradient(ellipse at center, #000 20%, transparent 72%); mask-image: radial-gradient(ellipse at center, #000 20%, transparent 72%);
}

/* Títulos con degradado animado */
.hero h1, .lesson-head h1 {
  background: linear-gradient(100deg, var(--text) 0%, var(--accent) 45%, var(--accent-2) 60%, var(--text) 100%);
  background-size: 250% 100%; -webkit-background-clip: text; background-clip: text; color: transparent; -webkit-text-fill-color: transparent;
  animation: sheen 9s ease-in-out infinite alternate;
}
@keyframes sheen { to { background-position: 100% 0; } }
.hero .eyebrow { position: relative; overflow: hidden; animation: rise .5s ease both; }
.hero .eyebrow::after { content: ""; position: absolute; inset: 0; background: linear-gradient(110deg, transparent 30%, rgba(255, 255, 255, .55) 50%, transparent 70%); transform: translateX(-120%); animation: shine 4.5s ease-in-out 1.2s infinite; }
@keyframes shine { 60%, 100% { transform: translateX(120%); } }

/* Barra superior que se compacta al bajar */
.topbar { transition: padding .25s, box-shadow .25s, background .25s; }
.topbar.compact { padding-top: .4rem; padding-bottom: .4rem; box-shadow: 0 6px 24px rgba(20, 23, 43, .12); }
.brand-logo { transition: transform .4s cubic-bezier(.2, 1.6, .4, 1); }
.brand:hover .brand-logo { transform: rotate(-12deg) scale(1.12); }
.icon-btn { transition: transform .15s, background .2s, border-color .2s; }
.icon-btn:hover { transform: translateY(-1px); border-color: var(--accent); }
.icon-btn:active { transform: scale(.95); }
.kbd-hint { font-family: var(--mono); font-size: .72rem; padding: .05rem .4rem; margin-left: .35rem; border: 1px solid var(--border); border-bottom-width: 2px; border-radius: 6px; color: var(--muted); }
@media (max-width: 700px) { .kbd-hint { display: none; } }

/* Botones: brillo y ondas */
.btn { position: relative; overflow: hidden; background-image: linear-gradient(120deg, var(--accent), color-mix(in srgb, var(--accent) 60%, var(--accent-2))); box-shadow: 0 8px 22px -8px var(--glow); transition: transform .2s, box-shadow .2s; }
.btn:hover { transform: translateY(-3px); box-shadow: 0 14px 30px -10px var(--glow); }
.btn.secondary { background-image: none; box-shadow: none; }
.btn::after { content: ""; position: absolute; inset: 0; background: linear-gradient(110deg, transparent 35%, rgba(255, 255, 255, .35) 50%, transparent 65%); transform: translateX(-130%); transition: transform .6s; pointer-events: none; }
.btn:hover::after { transform: translateX(130%); }
.ripple { position: absolute; border-radius: 50%; background: rgba(255, 255, 255, .45); transform: scale(0); animation: ripple .6s ease-out forwards; pointer-events: none; }
@keyframes ripple { to { transform: scale(4); opacity: 0; } }

/* Tarjetas: brillo que sigue al cursor + inclinación 3D */
.fx-card { position: relative; transform-style: preserve-3d; transition: transform .2s ease, border-color .2s, box-shadow .2s; }
.fx-card::before {
  content: ""; position: absolute; inset: 0; border-radius: inherit; pointer-events: none; z-index: 0; opacity: 0; transition: opacity .25s;
  background: radial-gradient(360px circle at var(--mx, 50%) var(--my, 50%), color-mix(in srgb, var(--accent) 22%, transparent), transparent 45%);
}
.fx-card:hover::before { opacity: 1; }
.fx-card > * { position: relative; z-index: 1; }
.fx-card.tilting { transition: transform .06s linear, border-color .2s, box-shadow .2s; box-shadow: 0 22px 44px -18px var(--glow); transform: perspective(900px) rotateX(var(--rx, 0deg)) rotateY(var(--ry, 0deg)) translateY(-4px) !important; }
.course-card h3, .lesson-card h3 { transition: color .2s; }
a.course-card:hover h3, a.lesson-card:hover h3 { color: var(--accent); }
.lesson-card.done::after { content: "✓"; position: absolute; top: .8rem; right: .9rem; display: grid; place-items: center; width: 1.6rem; height: 1.6rem; border-radius: 50%; background: var(--consejo); color: #fff; font-weight: 800; font-size: .85rem; animation: pop .5s cubic-bezier(.2, 1.6, .4, 1) both; z-index: 2; }
.route li.ok a { transition: transform .2s, border-color .2s, box-shadow .2s; }
.route li.ok a:hover { transform: translateY(-3px); box-shadow: var(--shadow); }
.route-n { transition: transform .3s cubic-bezier(.2, 1.6, .4, 1); }
.route li.ok a:hover .route-n { transform: scale(1.2) rotate(-8deg); }
.progress > div { background: linear-gradient(90deg, var(--accent), var(--accent-2)); position: relative; transition: width .8s cubic-bezier(.2, .8, .2, 1); }
.progress > div::after { content: ""; position: absolute; inset: 0; background: linear-gradient(110deg, transparent 30%, rgba(255, 255, 255, .5) 50%, transparent 70%); background-size: 200% 100%; animation: bar 2.4s linear infinite; }
@keyframes bar { from { background-position: 200% 0; } to { background-position: -100% 0; } }

/* Barra de lectura más viva */
.read-progress { background: linear-gradient(90deg, var(--accent), var(--accent-2), var(--accent-3)); box-shadow: 0 0 12px var(--glow); }

/* Índice lateral */
.toc a { transition: color .2s, border-color .2s, padding .2s; }
.toc a.active { padding-left: 1.3rem; font-weight: 600; }

/* Título con ancla copiable */
.h-anchor { margin-left: .5rem; padding: 0 .35rem; border: 0; border-radius: 6px; background: transparent; color: var(--accent); font: inherit; font-size: .8em; opacity: 0; cursor: pointer; transition: opacity .2s, background .2s; }
article h2:hover .h-anchor, article h3:hover .h-anchor, .h-anchor:focus-visible { opacity: 1; }
.h-anchor:hover { background: var(--accent-soft); }
@media (hover: none) { .h-anchor { display: none; } }

/* Código */
.code:hover { box-shadow: 0 18px 40px -18px var(--glow); }
.copy { transition: background .2s, transform .15s; }
.copy:active { transform: scale(.92); }

/* Tablas: filas con realce */
.table-wrap tbody tr { transition: background .15s; }
.table-wrap tbody tr:hover { background: var(--accent-soft); }

/* Quiz */
.quiz-score:not(:empty) { animation: pop .5s cubic-bezier(.2, 1.6, .4, 1) both; }

/* Marcar lección */
.complete { transition: border-color .3s, background .3s; }
.complete:has(.btn.done) { border-style: solid; border-color: var(--consejo); background: color-mix(in srgb, var(--consejo) 8%, var(--surface)); }

/* Volver arriba con anillo de progreso */
.to-top { position: fixed; right: 1.1rem; bottom: 1.1rem; z-index: 40; width: 3rem; height: 3rem; border: 0; border-radius: 50%; padding: 0; background: var(--surface); color: var(--accent); box-shadow: var(--shadow), 0 0 0 1px var(--border); cursor: pointer; display: grid; place-items: center; opacity: 0; transform: translateY(14px) scale(.8); pointer-events: none; transition: opacity .3s, transform .3s cubic-bezier(.2, 1.6, .4, 1); }
.to-top.show { opacity: 1; transform: none; pointer-events: auto; }
.to-top.show:hover { transform: translateY(-3px); }
.to-top svg { position: absolute; inset: 0; width: 100%; height: 100%; transform: rotate(-90deg); }
.to-top circle { fill: none; stroke-width: 3; }
.to-top .tt-bg { stroke: var(--border); }
.to-top .tt-fg { stroke: var(--accent); stroke-linecap: round; stroke-dasharray: 126; stroke-dashoffset: 126; transition: stroke-dashoffset .1s linear; }
.to-top span { position: relative; font-weight: 800; font-size: 1.05rem; line-height: 1; }

/* Avisos (toast) */
.toasts { position: fixed; left: 50%; bottom: 1.2rem; z-index: 90; display: grid; gap: .5rem; transform: translateX(-50%); pointer-events: none; }
.toast { padding: .65rem 1.1rem; border-radius: 999px; background: var(--code-bg); color: #fff; font-size: .92rem; font-weight: 600; box-shadow: 0 12px 30px rgba(0, 0, 0, .3); animation: toastIn .4s cubic-bezier(.2, 1.4, .4, 1) both; }
.toast.out { animation: toastOut .3s ease forwards; }
@keyframes toastIn { from { opacity: 0; transform: translateY(16px) scale(.9); } }
@keyframes toastOut { to { opacity: 0; transform: translateY(10px); } }

/* Confeti */
.confetti { position: fixed; inset: 0; z-index: 95; pointer-events: none; }

/* Buscador (Ctrl+K) */
.pal { position: fixed; inset: 0; z-index: 100; display: none; align-items: flex-start; justify-content: center; padding: 12vh 1rem 1rem; background: rgba(10, 12, 25, .55); backdrop-filter: blur(6px); }
.pal.open { display: flex; animation: fade .2s both; }
@keyframes fade { from { opacity: 0; } }
.pal-box { width: min(620px, 100%); max-height: 70vh; display: flex; flex-direction: column; border-radius: 18px; overflow: hidden; background: var(--surface); border: 1px solid var(--border); box-shadow: 0 30px 80px rgba(0, 0, 0, .45); animation: rise .3s cubic-bezier(.2, 1.2, .4, 1) both; }
.pal-box input { width: 100%; padding: 1.1rem 1.25rem; border: 0; border-bottom: 1px solid var(--border); background: transparent; color: var(--text); font: inherit; font-size: 1.1rem; outline: none; }
.pal-list { list-style: none; margin: 0; padding: .4rem; overflow: auto; }
.pal-list li { margin: 0; }
.pal-list a { display: flex; align-items: center; justify-content: space-between; gap: .75rem; padding: .65rem .85rem; border-radius: 10px; color: var(--text); text-decoration: none; }
.pal-list a.sel, .pal-list a:hover { background: var(--accent-soft); color: var(--accent); }
.pal-list small { flex: none; padding: .1rem .55rem; border-radius: 999px; background: var(--surface-2); color: var(--muted); font-weight: 700; font-size: .72rem; }
.pal-empty { padding: 1.2rem; text-align: center; color: var(--muted); }
.pal-foot { display: flex; gap: 1rem; padding: .5rem 1rem; border-top: 1px solid var(--border); font-size: .78rem; color: var(--muted); }

/* Entrada suave de página */
body { animation: pageIn .5s ease both; }
@keyframes pageIn { from { opacity: 0; } }

/* Subrayado degradado en títulos de sección */
h2.section-title::after { content: ""; display: block; height: 4px; width: 2.5rem; margin-top: .35rem; border-radius: 4px; background: linear-gradient(90deg, var(--accent), var(--accent-2)); transition: width .5s; }
h2.section-title:hover::after { width: 5rem; }

@media (prefers-reduced-motion: reduce) {
  .aurora i, .hero h1, .lesson-head h1, .hero .eyebrow::after, .progress > div::after, body, .toast, .pal-box { animation: none !important; }
  .fx-card.tilting { transform: none !important; }
  .btn::after { display: none; }
}
@media print { .aurora, .to-top, .toasts, .confetti, .pal { display: none !important; } .hero h1, .lesson-head h1 { -webkit-text-fill-color: currentColor; background: none; color: #000; } }
@media (max-width: 520px) { .icon-btn .lbl { display: none; } .topbar .brand { min-width: 0; overflow: hidden; text-overflow: ellipsis; } }

/* ==========================================================
   UI v4 · símbolos flotantes, cursor luminoso, cinta, XP/racha,
   botones magnéticos, bordes con degradado giratorio
   ========================================================== */
@property --ang { syntax: "<angle>"; initial-value: 0deg; inherits: false; }
body, .topbar, .feature, .lesson-card, .course-card, .quiz, .callout, .widget, .playground, .checker, .demo, details, .pager a { transition-property: background-color, color, border-color, box-shadow, transform, opacity; transition-duration: .35s; }

/* Símbolos de código flotando detrás del hero */
.float-syms { position: absolute; inset: 0; z-index: -1; overflow: hidden; pointer-events: none; }
.float-syms span { position: absolute; font-family: var(--mono); font-weight: 800; color: color-mix(in srgb, var(--accent) 20%, transparent); animation: bob var(--d, 9s) ease-in-out infinite alternate; animation-delay: var(--dl, 0s); left: var(--x); top: var(--y); font-size: var(--s, 2rem); }
@keyframes bob { from { transform: translateY(0) rotate(-8deg); } to { transform: translateY(-26px) rotate(10deg); } }

/* Luz que sigue al cursor */
.cursor-glow { position: fixed; left: 0; top: 0; z-index: 0; width: 520px; height: 520px; margin: -260px 0 0 -260px; border-radius: 50%; pointer-events: none; background: radial-gradient(circle, color-mix(in srgb, var(--accent) 16%, transparent), transparent 65%); opacity: 0; transition: opacity .4s; will-change: transform; }
.cursor-glow.on { opacity: 1; }

/* Cinta de tecnologías */
.ticker { overflow: hidden; margin: 1.5rem 0; padding: .7rem 0; border-block: 1px solid var(--border); -webkit-mask-image: linear-gradient(90deg, transparent, #000 10%, #000 90%, transparent); mask-image: linear-gradient(90deg, transparent, #000 10%, #000 90%, transparent); }
.ticker-track { display: flex; gap: 2.5rem; width: max-content; animation: marquee 32s linear infinite; font-family: var(--mono); font-weight: 700; color: var(--muted); }
.ticker:hover .ticker-track { animation-play-state: paused; }
.ticker-track span::before { content: "◆"; margin-right: 2.5rem; color: var(--accent); }
@keyframes marquee { to { transform: translateX(-50%); } }

/* Borde con degradado giratorio al pasar el ratón */
.course-card, .feature { --ang: 0deg; }
.course-card::after, .feature::after { content: ""; position: absolute; inset: -1px; border-radius: inherit; padding: 2px; pointer-events: none; opacity: 0; transition: opacity .3s;
  background: conic-gradient(from var(--ang), var(--accent), var(--accent-2), var(--accent-3), var(--accent));
  -webkit-mask: linear-gradient(#000 0 0) content-box, linear-gradient(#000 0 0); -webkit-mask-composite: xor; mask: linear-gradient(#000 0 0) content-box exclude, linear-gradient(#000 0 0); }
a.course-card:hover::after, .feature:hover::after { opacity: 1; animation: spin 3s linear infinite; }
@keyframes spin { to { --ang: 360deg; } }

/* Botones magnéticos */
.btn.mag { transition: transform .15s ease-out, box-shadow .2s; }

/* Insignia de XP / racha */
.xp { display: inline-flex; align-items: center; gap: .45rem; padding: .3rem .75rem; border: 1px solid var(--border); border-radius: 999px; background: var(--surface); font-size: .82rem; font-weight: 700; color: var(--text); white-space: nowrap; cursor: default; }
.xp b { color: var(--accent); }
.xp .xp-bar { width: 3.2rem; height: .4rem; border-radius: 99px; background: var(--surface-2); overflow: hidden; }
.xp .xp-bar i { display: block; height: 100%; width: 0; border-radius: inherit; background: linear-gradient(90deg, var(--accent), var(--accent-2)); transition: width .8s cubic-bezier(.2, .8, .2, 1); }
.xp.bump { animation: pop .6s cubic-bezier(.2, 1.6, .4, 1); }
@media (max-width: 700px) { .xp .xp-bar, .xp .xp-streak { display: none; } }
@media (max-width: 520px) { .xp { display: none; } }

/* Microinteracciones */
a.lesson-card:hover .lesson-num { animation: beat .8s ease-in-out infinite; }
@keyframes beat { 50% { transform: scale(1.12); transform-origin: left; } }
.opt.ok::after { content: " ✓"; font-weight: 800; color: var(--consejo-t); }
.opt.bad::after { content: " ✗"; font-weight: 800; color: var(--importante-t); }
article p a, article li a { text-decoration: none; background: linear-gradient(var(--accent), var(--accent)) 0 100% / 0 2px no-repeat; transition: background-size .3s; }
article p a:hover, article li a:hover { background-size: 100% 2px; }

@media (prefers-reduced-motion: reduce) { .float-syms span, .ticker-track, .cursor-glow, a.lesson-card:hover .lesson-num, a.course-card:hover::after, .feature:hover::after { animation: none !important; } .cursor-glow { display: none; } }
@media print { .float-syms, .cursor-glow, .ticker, .xp { display: none !important; } }
.course-card { position: relative; }

/* ==========================================================
   UI v5 · panel de progreso, ruta y temario animados
   ========================================================== */
.xp { font: inherit; font-size: .82rem; font-weight: 700; cursor: pointer; transition: transform .15s, border-color .2s; }
.xp:hover { border-color: var(--accent); transform: translateY(-1px); }

/* ----- Panel de progreso ----- */
.pp-box { position: relative; width: min(760px, 100%); max-height: 86vh; overflow: auto; padding: 1.5rem 1.5rem 1.75rem; display: block; }
.pp-close { position: absolute; top: .8rem; right: .8rem; z-index: 2; }
.pp-box h2 { margin: 0 0 .5rem; font-size: 1.6rem; }
.pp-box h3 { margin: 1.6rem 0 .6rem; font-size: 1.05rem; display: flex; align-items: baseline; gap: .5rem; }
.pp-box h3 small { color: var(--muted); font-weight: 600; }
.pp-head { display: flex; gap: 1.1rem; align-items: center; padding-right: 2.5rem; }
.pp-head > div:last-child { flex: 1; min-width: 0; }
.pp-av { display: grid; place-items: center; flex: none; width: 4.4rem; height: 4.4rem; border-radius: 22px; font-size: 2.3rem; background: linear-gradient(135deg, var(--accent-soft), color-mix(in srgb, var(--accent-2) 30%, var(--surface))); animation: float 4s ease-in-out infinite; }
.pp-kicker { margin: 0; font-size: .8rem; font-weight: 800; text-transform: uppercase; letter-spacing: .08em; color: var(--accent); }
.pp-small { margin: .35rem 0 0; font-size: .86rem; color: var(--muted); }
.pp-stats { display: grid; grid-template-columns: repeat(4, 1fr); gap: .6rem; margin: 1.2rem 0; }
.pp-stats > div { padding: .8rem .5rem; text-align: center; border: 1px solid var(--border); border-radius: 14px; background: var(--surface-2); }
.pp-stats b { display: block; font-size: 1.6rem; line-height: 1.1; color: var(--accent); }
.pp-stats span { font-size: .75rem; color: var(--muted); }
.pp-cta { display: block; text-align: center; margin: 0 0 .5rem; }
.pp-cta small { opacity: .8; }
.pp-goal { display: grid; grid-template-columns: auto 1fr; gap: 1.2rem; align-items: center; padding: 1rem; border: 1px solid var(--border); border-radius: 14px; background: var(--surface-2); }
.pp-goal p { margin: 0 0 .3rem; }
.pp-goal select { font: inherit; padding: .15rem .3rem; border-radius: 8px; border: 1px solid var(--border); background: var(--surface); color: var(--text); }
.pp-week { display: flex; align-items: flex-end; gap: .35rem; height: 5.2rem; }
.pp-day { display: flex; flex-direction: column; justify-content: flex-end; align-items: center; gap: .2rem; width: 1.5rem; height: 100%; }
.pp-day i { display: block; width: 100%; height: 12%; border-radius: 6px; background: var(--border); transform-origin: bottom; animation: grow .6s ease both; animation-delay: calc(var(--k, 0) * 60ms); }
.pp-day.on i { background: linear-gradient(180deg, var(--accent-2), var(--accent)); }
.pp-day.today span { color: var(--accent); font-weight: 800; }
.pp-day span { font-size: .7rem; color: var(--muted); }
@keyframes grow { from { transform: scaleY(0); } }
.pp-courses { display: grid; gap: .5rem; }
.pp-course { display: grid; grid-template-columns: 9.5rem 1fr 5.5rem; gap: .8rem; align-items: center; padding: .55rem .8rem; border: 1px solid var(--border); border-radius: 12px; color: var(--text); text-decoration: none; transition: border-color .2s, transform .2s; }
.pp-course:hover { border-color: var(--accent); transform: translateX(3px); }
.pp-course .progress { margin: 0; }
.pp-course small { text-align: right; color: var(--muted); font-weight: 700; }
.pp-logros { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: repeat(auto-fill, minmax(150px, 1fr)); gap: .6rem; }
.pp-logro { display: flex; flex-direction: column; gap: .1rem; padding: .8rem; border: 1px dashed var(--border); border-radius: 14px; opacity: .6; animation: pop .5s cubic-bezier(.2, 1.5, .4, 1) both; animation-delay: calc(var(--i) * 45ms); }
.pp-logro .ico { font-size: 1.7rem; filter: grayscale(1); }
.pp-logro small { color: var(--muted); font-size: .76rem; line-height: 1.3; }
.pp-logro.on { opacity: 1; border-style: solid; border-color: color-mix(in srgb, var(--accent) 45%, var(--border)); background: linear-gradient(160deg, var(--accent-soft), var(--surface)); }
.pp-logro.on .ico { filter: none; animation: beat 1.8s ease-in-out infinite; }
.pp-backup textarea { display: block; width: calc(100% - 2.2rem); margin: .5rem 1.1rem; padding: .6rem; border: 1px solid var(--border); border-radius: 10px; background: var(--code-bg); color: var(--code-text); font-family: var(--mono); font-size: .75rem; }
.pp-actions { display: flex; gap: .5rem; flex-wrap: wrap; margin: 0 1.1rem 1rem; }
@media (max-width: 600px) {
  .pp-stats { grid-template-columns: repeat(2, 1fr); }
  .pp-goal { grid-template-columns: 1fr; }
  .pp-course { grid-template-columns: 1fr; gap: .3rem; }
  .pp-course small { text-align: left; }
  .pp-head { flex-direction: column; align-items: flex-start; }
}

/* ----- Barra del temario ----- */
.tema-bar { display: flex; flex-wrap: wrap; align-items: center; gap: 1rem 1.5rem; margin: 0 0 1.2rem; padding: 1rem 1.2rem; border: 1px solid var(--border); border-radius: var(--radius); background: var(--surface); box-shadow: var(--shadow); }
.ring { position: relative; width: 4rem; height: 4rem; flex: none; }
.ring svg { width: 100%; height: 100%; transform: rotate(-90deg); }
.ring circle { fill: none; stroke-width: 5; }
.r-bg { stroke: var(--surface-2); }
.r-fg { stroke: url(#none); stroke: var(--accent); stroke-linecap: round; transition: stroke-dashoffset 1.2s cubic-bezier(.2, .8, .2, 1); }
.ring b { position: absolute; inset: 0; display: grid; place-items: center; font-size: .95rem; }
.tema-txt { flex: 1 1 200px; display: grid; }
.tema-txt span { color: var(--muted); font-size: .92rem; }
.chips { display: flex; gap: .4rem; flex-wrap: wrap; }
.chip { padding: .35rem .9rem; border: 1px solid var(--border); border-radius: 999px; background: var(--bg); color: var(--text); font: inherit; font-size: .88rem; font-weight: 600; cursor: pointer; transition: all .2s; }
.chip:hover { border-color: var(--accent); }
.chip.on { background: var(--accent); border-color: var(--accent); color: var(--accent-text); }
.lessons > li[hidden] { display: none; }
a.lesson-card.here { border-color: var(--accent); box-shadow: 0 0 0 3px color-mix(in srgb, var(--accent) 25%, transparent), var(--shadow); animation: hereGlow 2.2s ease-in-out infinite; }
@keyframes hereGlow { 50% { box-shadow: 0 0 0 7px color-mix(in srgb, var(--accent) 12%, transparent), var(--shadow); } }
.here-badge { position: absolute !important; top: -.7rem; right: .9rem; z-index: 3; padding: .15rem .7rem; border-radius: 999px; background: var(--accent); color: var(--accent-text); font-size: .75rem; font-weight: 800; box-shadow: 0 6px 16px -4px var(--glow); animation: bounce 1.6s ease-in-out infinite; }
@keyframes bounce { 50% { transform: translateY(-4px); } }
.lesson-card.done .tag.done { animation: pop .5s both; }

/* ----- Ruta animada ----- */
.route-cta { display: inline-block; margin: 0 0 1.2rem; }
.route-track { position: relative; display: flex; justify-content: space-between; align-items: center; margin: 1rem 0 1.4rem; padding: 0 .9rem; }
.rt-line { position: absolute; left: 1.4rem; right: 1.4rem; top: 50%; height: 6px; margin-top: -3px; border-radius: 6px; background: var(--surface-2); overflow: hidden; }
.rt-line i { display: block; width: 0; height: 100%; border-radius: inherit; background: linear-gradient(90deg, var(--accent), var(--accent-2), var(--accent-3)); background-size: 200% 100%; animation: flowbar 3s linear infinite; transition: width 1.6s cubic-bezier(.2, .8, .2, 1) .2s; }
.route-track.go .rt-line i { width: var(--w); }
@keyframes flowbar { to { background-position: -200% 0; } }
.rt-dot { position: relative; z-index: 1; display: grid; place-items: center; width: 2rem; height: 2rem; border-radius: 50%; border: 2px solid var(--border); background: var(--surface); color: var(--muted); font-size: .8rem; font-weight: 800; opacity: 0; transform: scale(.4); }
.route-track.go .rt-dot { animation: pop .5s cubic-bezier(.2, 1.6, .4, 1) both; animation-delay: calc(var(--i) * 160ms); }
.rt-dot.done { background: var(--consejo); border-color: var(--consejo); color: #fff; }
.rt-dot.cur { border-color: var(--accent); color: var(--accent); }
.route-track.go .rt-dot.cur::after { content: ""; position: absolute; inset: -6px; border-radius: 50%; border: 2px solid var(--accent); animation: ping 1.8s ease-out infinite; }
@keyframes ping { from { transform: scale(.7); opacity: .9; } to { transform: scale(1.5); opacity: 0; } }
.rt-dot.soon { border-style: dashed; }
.route li { position: relative; }
.route.pre li { opacity: 0; transform: translateY(18px); }
.route:not(.pre) li { animation: rise .55s ease both; animation-delay: calc(var(--i, 0) * 110ms); }
.route li.ok > a, .route li.soon > div { position: relative; }
.route li.current > a { border-color: var(--accent); box-shadow: 0 0 0 3px color-mix(in srgb, var(--accent) 22%, transparent); animation: hereGlow 2.2s ease-in-out infinite; }
.route li.finished > a { border-color: color-mix(in srgb, var(--consejo) 55%, var(--border)); }
.route li.finished .route-n { background: var(--consejo); }
.route li.finished .route-n { font-size: 0; }
.route li.finished .route-n::before { content: "✓"; font-size: .9rem; }
.route-bar { display: block; height: 5px; margin-top: .45rem; border-radius: 5px; background: var(--surface-2); overflow: hidden; }
.route-bar i { display: block; height: 100%; border-radius: inherit; background: linear-gradient(90deg, var(--accent), var(--accent-2)); transition: width 1.2s cubic-bezier(.2, .8, .2, 1) .5s; }
.route li.soon div { transition: transform .3s; }
.route li.soon div:hover { transform: rotate(-1.2deg) scale(1.02); }
.route li.soon .route-n { animation: bounce 2.4s ease-in-out infinite; animation-delay: calc(var(--i, 0) * 120ms); }
@media (max-width: 600px) { .rt-dot { width: 1.6rem; height: 1.6rem; font-size: .7rem; } .route-track { padding: 0 .4rem; } .rt-line { left: .8rem; right: .8rem; } }
@media (prefers-reduced-motion: reduce) {
  .route.pre li { opacity: 1; transform: none; }
  .rt-dot { opacity: 1; transform: none; animation: none !important; }
  .rt-line i, .here-badge, a.lesson-card.here, .pp-av, .pp-logro, .pp-logro.on .ico, .route li.current > a, .route li.soon .route-n, .pp-day i { animation: none !important; }
  .route-track .rt-line i { width: var(--w); }
}
@media print { .tema-bar, .route-track, .route-cta, .prog-pal { display: none !important; } }
@media (max-width: 520px) { .xp { display: inline-flex; padding: .3rem .55rem; } }

/* ----- Temas desbloqueables por nivel ----- */
html:root[data-skin="oceano"][data-skin] { --accent: #0891b2; --accent-soft: #cffafe; --accent-2: #67e8f9; --glow: #0891b247; }
html:root[data-skin="oceano"][data-theme="dark"] { --accent: #67e8f9; --accent-soft: #164e63; --accent-2: #0891b2; --glow: #67e8f947; }
@media (prefers-color-scheme: dark) { html:root[data-skin="oceano"][data-skin]:not([data-theme="light"]) { --accent: #67e8f9; --accent-soft: #164e63; --accent-2: #0891b2; --glow: #67e8f947; } }
html:root[data-skin="atardecer"][data-skin] { --accent: #ea580c; --accent-soft: #ffedd5; --accent-2: #fdba74; --glow: #ea580c47; }
html:root[data-skin="atardecer"][data-theme="dark"] { --accent: #fdba74; --accent-soft: #4a2410; --accent-2: #ea580c; --glow: #fdba7447; }
@media (prefers-color-scheme: dark) { html:root[data-skin="atardecer"][data-skin]:not([data-theme="light"]) { --accent: #fdba74; --accent-soft: #4a2410; --accent-2: #ea580c; --glow: #fdba7447; } }
html:root[data-skin="bosque"][data-skin] { --accent: #15803d; --accent-soft: #dcfce7; --accent-2: #86efac; --glow: #15803d47; }
html:root[data-skin="bosque"][data-theme="dark"] { --accent: #86efac; --accent-soft: #14391f; --accent-2: #15803d; --glow: #86efac47; }
@media (prefers-color-scheme: dark) { html:root[data-skin="bosque"][data-skin]:not([data-theme="light"]) { --accent: #86efac; --accent-soft: #14391f; --accent-2: #15803d; --glow: #86efac47; } }
html:root[data-skin="neon"][data-skin] { --accent: #c026d3; --accent-soft: #fae8ff; --accent-2: #f0abfc; --glow: #c026d347; }
html:root[data-skin="neon"][data-theme="dark"] { --accent: #f0abfc; --accent-soft: #4a1252; --accent-2: #c026d3; --glow: #f0abfc47; }
@media (prefers-color-scheme: dark) { html:root[data-skin="neon"][data-skin]:not([data-theme="light"]) { --accent: #f0abfc; --accent-soft: #4a1252; --accent-2: #c026d3; --glow: #f0abfc47; } }

.pp-skins, .pp-avs { display: flex; flex-wrap: wrap; gap: .5rem; margin: 0 0 .7rem; }
.pp-skin { display: inline-flex; align-items: center; gap: .45rem; padding: .35rem .8rem; border: 1px solid var(--border); border-radius: 999px; background: var(--bg); color: var(--text); font: inherit; font-size: .86rem; font-weight: 600; cursor: pointer; transition: all .2s; }
.pp-skin i { width: .9rem; height: .9rem; border-radius: 50%; }
.pp-skin:hover:not(:disabled) { border-color: var(--accent); }
.pp-skin.on { border-color: var(--accent); box-shadow: 0 0 0 3px color-mix(in srgb, var(--accent) 25%, transparent); }
.pp-skin:disabled, .pp-avb:disabled { opacity: .5; cursor: not-allowed; }
.pp-avb { width: 2.6rem; height: 2.6rem; border: 1px solid var(--border); border-radius: 12px; background: var(--bg); font-size: 1.4rem; cursor: pointer; transition: transform .2s, border-color .2s; }
.pp-avb:hover:not(:disabled) { transform: translateY(-2px) scale(1.08); border-color: var(--accent); }
.pp-avb.on { border-color: var(--accent); background: var(--accent-soft); }
.pp-daily { padding: 1rem; border: 1px solid var(--border); border-radius: 14px; background: var(--surface-2); }
.pp-daily p { margin: 0 0 .6rem; }
.pp-dopts { display: flex; flex-wrap: wrap; gap: .5rem; }
.pp-dopts .chip:disabled { opacity: .6; cursor: default; }
.pp-dopts .chip.on:disabled { opacity: 1; }
.pp-act0 { margin: 0 0 .5rem; }
.pp-act0 a { text-decoration: none; color: var(--text); }
.topbar-actions .icon-btn { white-space: nowrap; }
@media (max-width: 520px) { .topbar-actions { gap: .35rem; } .topbar-actions .icon-btn { padding-inline: .6rem; } .xp .xp-bar { display: none; } }

/* Comunidad */
.pp-rank { margin: 0 0 .8rem; padding-left: 1.3rem; }
.pp-rank li { padding: .15rem 0; }
.pp-rank small { color: var(--muted); }
#pp-com input { padding: .5rem .7rem; border: 1px solid var(--border); border-radius: 10px; background: var(--bg); color: var(--text); font: inherit; }
#pp-com .pp-actions { margin: .6rem 0 0; }

@media(max-width:480px){pre.sql-out{white-space:pre-wrap;overflow-wrap:anywhere}}