:root {
  --bg: #14171c; --panel: #1c2028; --border: #2b303a; --text: #e8eaed;
  --muted: #9aa1ac; --accent: #5fb3a3; --accent-hover: #4c9a8b; --danger: #d9756a;
}
* { box-sizing: border-box; }
body { margin:0; font-family:-apple-system,"Segoe UI",Roboto,sans-serif; background:var(--bg); color:var(--text); }
h1 { font-size:1.25rem; font-weight:600; margin:0; }
label { display:block; font-size:.85rem; color:var(--muted); margin:1rem 0 .35rem; }
input, textarea, select {
  width:100%; background:var(--panel); border:1px solid var(--border); color:var(--text);
  padding:.6rem .7rem; border-radius:6px; font-size:.92rem; font-family:inherit;
}
textarea { resize:vertical; min-height:80px; }
textarea.mono { font-family:ui-monospace,"SF Mono",Consolas,monospace; font-size:.82rem; }
button.primary { margin-top:1.25rem; background:var(--accent); color:#0e1512; border:none; padding:.7rem 1.3rem; border-radius:6px; font-size:.95rem; font-weight:600; cursor:pointer; }
button.primary:hover { background:var(--accent-hover); }
button.primary:disabled { opacity:.5; cursor:not-allowed; }
button.secondary { margin-top:.6rem; background:transparent; color:var(--accent); border:1px solid var(--accent); padding:.5rem .9rem; border-radius:6px; cursor:pointer; font-size:.85rem; }
button.icon { background:var(--panel); border:1px solid var(--border); color:var(--text); padding:.5rem 1rem; border-radius:6px; cursor:pointer; font-size:.85rem; }
button.icon:disabled { opacity:.35; cursor:not-allowed; }
.msg { margin-top:.75rem; font-size:.85rem; min-height:1.2em; }
.msg.ok { color:var(--accent); } .msg.error { color:var(--danger); }
.row { display:flex; gap:.75rem; } .row > div { flex:1; }
.hint { color:var(--muted); font-size:.76rem; margin-top:.25rem; }
.card { background:var(--panel); border:1px solid var(--border); border-radius:10px; padding:1.25rem 1.5rem; margin-top:1rem; }
fieldset { border:1px solid var(--border); border-radius:8px; padding:1rem; margin-top:1.5rem; }
legend { padding:0 .5rem; color:var(--muted); font-size:.85rem; }

/* Reproductor */
.viewer { min-height: 280px; }
.progressbar { height:4px; background:var(--border); border-radius:2px; overflow:hidden; margin:1rem 0; }
.progressbar-fill { height:100%; background:var(--accent); transition:width .2s; }
.slide-kicker { font-size:.78rem; color:var(--accent); text-transform:uppercase; letter-spacing:.03em; margin-bottom:.4rem; }
.slide-title { font-size:1.2rem; font-weight:600; margin-bottom:.75rem; }
.slide-body { font-size:.95rem; line-height:1.65; white-space:pre-wrap; }
.slide-svg { margin:1rem 0; text-align:center; }
.slide-imagen { margin:1rem 0; }
.nav-row { display:flex; justify-content:space-between; align-items:center; margin-top:1.5rem; }
.status-save { font-size:.78rem; color:var(--muted); }
.respuesta { border-top:1px solid var(--border); margin-top:.6rem; padding-top:.6rem; }

/* Visor: header / contenido / footer */
.viewer-header { margin-bottom: 1.25rem; }
.viewer-header-fila { display: flex; align-items: center; justify-content: space-between; }
.slide-contador { font-size: .76rem; color: var(--muted); }
.viewer .slide-contador { color: #6b6656; }
.viewer-content { min-height: 160px; }
.viewer-footer {
  display: flex; align-items: center; justify-content: space-between;
  gap: .75rem; margin-top: 1.5rem; padding-top: 1rem; border-top: 1px solid #d8d4c8;
}
.viewer-footer-nav { display: flex; gap: .5rem; }
.viewer-footer button.icon { font-size: 1rem; padding: .4rem .7rem; }

/* Imágenes con zoom */
.img-zoomable { max-width: 100%; border-radius: 6px; display: block; margin-bottom: .5rem; cursor: zoom-in; }
.zoom-overlay {
  position: fixed; inset: 0; background: rgba(0,0,0,.85);
  display: flex; align-items: center; justify-content: center;
  z-index: 1000; cursor: zoom-out;
}
.zoom-overlay img { max-width: 90vw; max-height: 90vh; border-radius: 8px; }

/* Gestión de imágenes por sesión */
.fila-imagen-gestion {
  display: grid; grid-template-columns: 1fr 140px auto; align-items: center;
  gap: 1rem; padding: .85rem 0; border-bottom: 1px solid var(--border);
}
.fila-imagen-preview { width: 140px; }
.fila-imagen-preview img { width: 140px; height: auto; border-radius: 6px; }
.fila-imagen-preview-vacia {
  display: flex; align-items: center; justify-content: center; text-align: center;
  font-size: .7rem; color: var(--muted); border: 1px dashed var(--border);
  border-radius: 6px; height: 90px; padding: .5rem; cursor: text; outline: none;
}
.fila-imagen-preview-vacia:focus { border-color: var(--accent); color: var(--accent); }
.fila-imagen-acciones { display: flex; gap: .4rem; white-space: nowrap; }
.fila-imagen-acciones button { margin-top: 0; }

/* Diapositiva: fondo claro, alto contraste para lectura de números/variables */
.viewer {
  background: #f7f5f0; color: #1a1a1a; border-color: #d8d4c8;
}
.viewer .slide-kicker { color: #2f7a6b; }
.viewer .slide-title { color: #111; }
.viewer .slide-body { color: #1a1a1a; }
.viewer strong { color: #1f6f5c; }
.viewer .msg.ok { color: #1f7a4d; }
.viewer .msg.error { color: #b3261e; }
.viewer .msg { color: #4a4636; }
.viewer .status-save { color: #6b6656; }
.viewer .progressbar { background: #d8d4c8; }
.viewer .pregunta-examen { border-color: #d8d4c8; }
.viewer mjx-container { background: rgba(31,111,92,0.10); }
.viewer button.icon, .viewer button.secondary {
  background: #fff; border-color: #b8b2a0; color: #1a1a1a;
}
.viewer button.icon:hover, .viewer button.secondary:hover { background: #ece8dc; }
.viewer button.icon:disabled { opacity: .35; }
.viewer button.primary { background: #1f6f5c; color: #fff; }
.viewer button.primary:hover { background: #185a4a; }
.viewer input, .viewer textarea, .viewer select {
  background: #fff; border-color: #b8b2a0; color: #1a1a1a;
}

/* Tablas dentro de la diapositiva */
.tabla-md { border-collapse: collapse; width: 100%; margin: .75rem 0; font-size: .9rem; }
.tabla-md th, .tabla-md td { border: 1px solid #b8b2a0; padding: .5rem .6rem; text-align: left; }
.tabla-md th { background: #eae6da; color: #111; font-weight: 600; }
.tabla-md tr:nth-child(even) td { background: #fbfaf6; }
.pregunta-examen { margin-bottom:1.5rem; padding-bottom:1.25rem; border-bottom:1px solid var(--border); }
.pregunta-examen:last-of-type { border-bottom:none; }
.pregunta-examen textarea { min-height:70px; margin-top:.5rem; }
.feedback-ia { margin-top:.6rem; }
.feedback-ia .msg { font-size:.85rem; line-height:1.5; }

/* Color para mejorar lectura */
strong { color: var(--accent); }
.slide-body ul, .chat-burbuja ul { margin: .4rem 0; padding-left: 1.2rem; }
.slide-body li, .chat-burbuja li { margin-bottom: .3rem; }
mjx-container { background: rgba(95,179,163,0.10); border-radius: 3px; padding: 0 2px; }

/* ==========================================
   APP SHELL — header / sidebars / main / footer
   ========================================== */
.app-shell {
  display: grid;
  grid-template-columns: 200px 1fr 300px;
  grid-template-rows: auto 1fr auto;
  grid-template-areas:
    "header header header"
    "sidebar-left main sidebar-right"
    "footer footer footer";
  height: 100vh;
  max-width: 1400px;
  margin: 0 auto;
  overflow: hidden;
}

.app-header {
  grid-area: header;
  display: flex; align-items: center; justify-content: space-between;
  padding: .9rem 1.5rem; border-bottom: 1px solid var(--border);
  gap: 1rem; flex-wrap: wrap;
}
.header-estado { display: flex; gap: .5rem; flex-wrap: wrap; }
.pill {
  font-size: .76rem; padding: .3rem .7rem; border-radius: 999px;
  background: var(--panel); border: 1px solid var(--border); color: var(--muted);
  white-space: nowrap;
}
.pill.on { color: var(--accent); border-color: var(--accent); }

.app-sidebar-left {
  grid-area: sidebar-left;
  border-right: 1px solid var(--border);
  padding: 1rem .75rem;
  overflow-y: auto;
}
.side-nav-item {
  display: block; width: 100%; text-align: left; background: none; border: none;
  color: var(--muted); font-size: .92rem; padding: .6rem .75rem; border-radius: 6px;
  cursor: pointer; margin-bottom: .15rem;
}
.side-nav-item:hover { background: var(--panel); color: var(--text); }
.side-nav-item.active { background: var(--panel); color: var(--accent); font-weight: 600; }

.app-main {
  grid-area: main;
  padding: 1.5rem; overflow-y: auto;
}
.app-main .panel { display: none; }
.app-main .panel.active { display: block; }

.app-sidebar-right {
  grid-area: sidebar-right;
  border-left: 1px solid var(--border);
  padding: 1rem; overflow-y: auto;
  display: flex; flex-direction: column; gap: 1.25rem;
}
.sidebar-block h3 {
  font-size: .78rem; text-transform: uppercase; letter-spacing: .03em;
  color: var(--muted); margin: 0 0 .5rem;
}
#logTodas, #resumenExamen { margin-top: 0; max-height: 220px; overflow-y: auto; font-size: .82rem; }

.chat-block { flex: 1; display: flex; flex-direction: column; min-height: 240px; }
.chat-mensajes {
  flex: 1; overflow-y: auto; display: flex; flex-direction: column; gap: .6rem;
  margin-bottom: .6rem; min-height: 120px;
}
.chat-burbuja { font-size: .85rem; line-height: 1.5; padding: .55rem .75rem; border-radius: 10px; max-width: 92%; }
.chat-burbuja.usuario { align-self: flex-end; background: var(--accent); color: #0e1512; }
.chat-burbuja.ia { align-self: flex-start; background: var(--panel); border: 1px solid var(--border); }
.chat-input-row {
  display: flex; align-items: flex-end; gap: .4rem;
  background: var(--bg); border: 1px solid var(--border); border-radius: 20px;
  padding: .4rem .4rem .4rem 1rem;
}
.chat-input-row textarea {
  flex: 1; border: none; background: transparent; resize: none;
  padding: .5rem 0; min-height: 22px; max-height: 120px; font-size: .85rem;
}
.chat-input-row textarea:focus { outline: none; }
.chat-input-actions { display: flex; gap: .3rem; flex-shrink: 0; }
.chat-icon-btn {
  width: 34px; height: 34px; border-radius: 50%; border: none;
  background: var(--panel); color: var(--text); cursor: pointer;
  display: flex; align-items: center; justify-content: center; font-size: 1rem;
  flex-shrink: 0; padding: 0;
}
.chat-icon-btn:hover { background: var(--border); }
.chat-icon-btn:disabled { opacity: .4; cursor: not-allowed; }
.chat-send-btn { background: var(--accent); color: #0e1512; }
.chat-send-btn:hover { background: var(--accent-hover); }

.app-footer {
  grid-area: footer;
  border-top: 1px solid var(--border);
  padding: .6rem 1.5rem; font-size: .8rem; color: var(--muted);
}

@media (max-width: 900px) {
  .app-shell {
    height: auto;
    overflow: visible;
    grid-template-columns: 1fr;
    grid-template-areas:
      "header"
      "sidebar-left"
      "main"
      "sidebar-right"
      "footer";
  }
  .app-sidebar-left { border-right: none; border-bottom: 1px solid var(--border); display: flex; flex-wrap: wrap; gap: .25rem; overflow-y: visible; }
  .app-sidebar-right { border-left: none; border-top: 1px solid var(--border); overflow-y: visible; }
  .app-main { overflow-y: visible; }
}