:root {
  --aviso: 30px;
  --papel: #f7f6f2;
  --tarjeta: #ffffff;
  --tinta: #14181f;
  --tinta-2: #4a5160;
  --tenue: #7a8090;
  --linea: #14181f;
  --linea-2: #d4d2ca;
  --enfasis: #c2410c;
  --enfasis-suave: #fbeee6;
  --rejilla: rgba(20, 24, 31, 0.05);
  --poche: #e9c9b4;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --papel: #12151b; --tarjeta: #1a1e26; --tinta: #eceae4; --tinta-2: #b9bcc4;
    --tenue: #8b909c; --linea: #eceae4; --linea-2: #343a46; --enfasis: #f08a4b;
    --enfasis-suave: #2a1e17; --rejilla: rgba(236, 234, 228, 0.05); --poche: #5a3a2a;
  }
}
:root[data-theme="dark"] {
  --papel: #12151b; --tarjeta: #1a1e26; --tinta: #eceae4; --tinta-2: #b9bcc4;
  --tenue: #8b909c; --linea: #eceae4; --linea-2: #343a46; --enfasis: #f08a4b;
  --enfasis-suave: #2a1e17; --rejilla: rgba(236, 234, 228, 0.05); --poche: #5a3a2a;
}

* { box-sizing: border-box; }
[hidden] { display: none !important; }
html, body { margin: 0; height: 100%; }
body {
  background-color: var(--papel);
  background-image:
    repeating-linear-gradient(0deg, var(--rejilla) 0 1px, transparent 1px 28px),
    repeating-linear-gradient(90deg, var(--rejilla) 0 1px, transparent 1px 28px);
  color: var(--tinta);
  font: 14px/1.5 'IBM Plex Sans', system-ui, sans-serif;
  overflow: hidden;
}
.mono { font-family: 'IBM Plex Mono', ui-monospace, monospace; }
.tenue { color: var(--tenue); }
.pequeno { font-size: 12px; margin: 0 0 12px; }
button { font: inherit; color: inherit; cursor: pointer; }
button:focus-visible, input:focus-visible { outline: 2px solid var(--enfasis); outline-offset: 2px; }

#lienzo { position: fixed; inset: 0; }
#lienzo canvas { display: block; }

.marco {
  position: fixed; inset: calc(10px + var(--aviso)) 10px 10px; border: 1px solid color-mix(in srgb, var(--linea) 22%, transparent);
  pointer-events: none; font: 11px 'IBM Plex Mono', monospace; color: var(--tenue);
}
.marco-a { position: absolute; left: 8px; bottom: 6px; }
.marco-b { position: absolute; right: 8px; bottom: 6px; }

.panel, .barra, .controles, .sistemas {
  background: var(--tarjeta);
  border: 1.5px solid var(--linea);
  box-shadow: 5px 5px 0 color-mix(in srgb, var(--linea) 12%, transparent);
}
.eyebrow {
  font: 600 11px 'IBM Plex Mono', monospace; letter-spacing: .08em; text-transform: uppercase; color: var(--enfasis);
}

.aviso {
  position: fixed; top: 0; left: 0; right: 0; z-index: 4; height: var(--aviso); margin: 0;
  display: flex; align-items: center; justify-content: center; gap: 12px; padding: 0 16px;
  background: var(--enfasis-suave); border-bottom: 1.5px solid var(--linea);
  font: 500 12px 'IBM Plex Mono', monospace; color: var(--tinta-2); white-space: nowrap; overflow: hidden;
}
.aviso span { overflow: hidden; text-overflow: ellipsis; }
.aviso a { color: var(--enfasis); font-weight: 600; text-underline-offset: 2px; flex-shrink: 0; }
.aviso a:focus-visible { outline: 2px solid var(--enfasis); outline-offset: 2px; }

.barra {
  position: fixed; top: calc(20px + var(--aviso)); left: 20px; right: 20px; z-index: 3;
  display: flex; align-items: center; justify-content: space-between; gap: 12px; padding: 8px 14px;
}
.marca { display: flex; align-items: center; gap: 12px; }
.marca-cuadro { width: 14px; height: 14px; background: var(--enfasis); border: 1.5px solid var(--linea); }
.barra h1 { margin: 0; font-size: 16px; font-weight: 700; letter-spacing: -.01em; }
.barra h1 .tenue { font-weight: 500; }
.vistas { display: flex; gap: 6px; }
.vistas button, .ejes button {
  border: 1.5px solid var(--linea); background: var(--tarjeta); padding: 6px 12px;
  font: 600 12px 'IBM Plex Mono', monospace;
}
.vistas button.activo, .ejes button.activo { background: var(--tinta); color: var(--papel); }
.vistas button:disabled { opacity: .35; cursor: default; }
.vistas .copiar { margin-left: 6px; border-color: var(--enfasis); color: var(--enfasis); min-width: 13ch; }

.panel { position: fixed; z-index: 2; padding: 16px; overflow: auto; }
.panel-izq { top: calc(84px + var(--aviso)); left: 20px; width: 300px; bottom: 150px; }
.panel-der { top: calc(84px + var(--aviso)); right: 20px; width: 340px; max-height: calc(100% - 240px - var(--aviso)); }
.panel-cab {
  display: flex; justify-content: space-between; align-items: center;
  border-bottom: 1.5px solid var(--linea); padding-bottom: 8px; margin-bottom: 12px;
}
.panel h2 { font-size: 18px; margin: 0 0 8px; line-height: 1.25; }
.cuerpo { font-size: 13px; color: var(--tinta-2); margin: 0 0 12px; }
.enlace { background: none; border: 0; padding: 0; font-size: 11px; text-decoration: underline; color: var(--tenue); }
.enlace:hover { color: var(--tinta); }

.lecciones { list-style: none; margin: 0; padding: 0; counter-reset: l; }
.lecciones li + li { margin-top: 4px; }
.lecciones .nivel {
  font: 600 11px 'IBM Plex Mono', monospace; color: var(--tenue); text-transform: uppercase;
  letter-spacing: .08em; margin: 14px 0 6px; padding-top: 10px; border-top: 1px solid var(--linea-2);
}
.lecciones .nivel:first-child { margin-top: 0; padding-top: 0; border-top: 0; }
.leccion {
  width: 100%; text-align: left; display: grid; grid-template-columns: 30px 1fr; gap: 8px;
  border: 1.5px solid transparent; background: none; padding: 8px; border-radius: 0;
}
.leccion:hover { border-color: var(--linea-2); }
.leccion.activo { border-color: var(--linea); background: var(--enfasis-suave); }
.leccion .num { font: 600 12px 'IBM Plex Mono', monospace; color: var(--enfasis); }
.leccion b { display: block; font-size: 13px; font-weight: 600; }
.leccion small { display: block; font-size: 12px; color: var(--tenue); }
.leccion .mec { font: 500 11px 'IBM Plex Mono', monospace; color: var(--enfasis); }

.datos { margin: 0 0 12px; border-top: 1px solid var(--linea-2); }
.datos div { display: flex; justify-content: space-between; gap: 12px; border-bottom: 1px solid var(--linea-2); padding: 6px 0; font-size: 12px; }
.datos dt { color: var(--tenue); font-family: 'IBM Plex Mono', monospace; font-size: 11px; text-transform: uppercase; }
.datos dd { margin: 0; text-align: right; font-weight: 600; }
.bloque { background: var(--papel); border: 1px solid var(--linea-2); padding: 10px 12px; margin-bottom: 8px; }
.bloque p { margin: 4px 0 0; font-size: 13px; }
.sello { font-size: 11px; color: var(--tenue); margin: 10px 0 0; }
.sello b { color: var(--tinta-2); font-weight: 600; }

.controles {
  position: fixed; left: 20px; bottom: 20px; width: 300px; z-index: 2; padding: 12px 14px;
  display: grid; gap: 10px;
}
.controles label { display: grid; grid-template-columns: 1fr auto; font-size: 12px; font-weight: 600; gap: 4px; }
.controles label .mono { color: var(--enfasis); font-weight: 600; }
.controles input[type="range"] { grid-column: 1 / -1; width: 100%; accent-color: var(--enfasis); }
.ejes { display: flex; gap: 4px; }
.ayuda { margin: -4px 0 0; font-size: 11px; color: var(--tenue); }
.ejes button { flex: 1; padding: 4px 6px; font-size: 11px; }

.sistemas {
  position: fixed; bottom: 20px; left: 340px; right: 20px; z-index: 2; padding: 8px;
  display: flex; flex-wrap: wrap; gap: 6px; justify-content: center;
}
.sistemas button {
  border: 1.5px solid var(--linea-2); background: var(--tarjeta); padding: 6px 10px;
  font: 600 11px 'IBM Plex Mono', monospace; text-transform: uppercase;
}
.sistemas button:hover { border-color: var(--linea); }
.sistemas button.activo { background: var(--enfasis); border-color: var(--enfasis); color: #fff; }

.lectura {
  position: fixed; z-index: 2; left: 50%; transform: translateX(-50%); top: calc(92px + var(--aviso)); max-width: 520px;
  background: var(--tarjeta); border: 1.5px solid var(--enfasis); padding: 8px 14px; text-align: center;
}
.lectura p { margin: 0; font-size: 12px; color: var(--tinta-2); }
.lectura .mono { font-size: 13px; font-weight: 600; color: var(--enfasis); white-space: pre-line; }
.lectura .mono:empty { display: none; }
.rotulo-3d {
  font: 600 11px 'IBM Plex Mono', monospace; color: var(--tinta); background: var(--tarjeta);
  border: 1px solid var(--linea); padding: 2px 6px; white-space: nowrap;
}
.rotulo-3d.enfasis { color: var(--enfasis); border-color: var(--enfasis); }
.carga {
  position: fixed; inset: 0; display: grid; place-items: center; z-index: 9; background: var(--papel);
  transition: opacity .4s;
}
.carga.fuera { opacity: 0; pointer-events: none; }

@media (max-width: 900px) {
  html, body { height: auto; }
  body { overflow: auto; display: flex; flex-direction: column; padding-bottom: 16px; }
  body > * { flex-shrink: 0; }
  .aviso {
    position: relative; height: auto; white-space: normal; flex-wrap: wrap; justify-content: flex-start;
    gap: 2px 10px; padding: 8px 16px; line-height: 1.4; font-size: 11px;
  }
  .aviso span { overflow: visible; }
  .aviso { padding-bottom: 0; row-gap: 0; }
  .aviso a { display: inline-flex; align-items: center; min-height: 44px; }
  /* blancos táctiles de 44 px en el teléfono */
  .enlace { display: inline-flex; align-items: center; min-height: 44px; padding: 0 4px; }
  .ejes button, .sistemas button { min-height: 44px; }
  .barra { position: sticky; top: 0; left: auto; right: auto; margin: 0 0 8px; border-width: 0 0 1.5px; box-shadow: none; }
  .barra h1 .tenue { display: none; }
  .barra .eyebrow { display: none; }
  .marco { display: none; }
  #lienzo { position: relative; height: 58vh; order: 2; scroll-margin-top: 60px; }
  .lectura { scroll-margin-top: 60px; }
  .lectura { position: relative; top: auto; left: auto; transform: none; max-width: none; margin: 0 16px 8px; order: 1; }
  .panel-izq, .panel-der, .controles, .sistemas {
    position: relative; inset: auto; width: auto; max-height: none; margin: 12px 16px 0;
  }
  .controles { order: 3; }
  .panel-der { order: 4; overflow: visible; }
  .sistemas { order: 5; justify-content: flex-start; }
  .panel-izq { order: 6; overflow: visible; }
}