/* =========================================================================
   flotacion.css — hoja propia del recurso «Flotación: el principio de
   Arquímedes». Se carga DESPUÉS de style.css y recurso.css y solo añade lo
   que el marco común no cubre: la paleta del depósito, las tarjetas de
   configuración (fluidos y cuerpos) y el panel de resultados.
   ========================================================================= */

/* ---- Paleta del depósito ------------------------------------------------
   Los fluidos NO codifican la densidad en la luminosidad: con 1-4 capas es
   más legible darles color propio y poner el número en su etiqueta. La
   inversión de densidades se avisa con texto, no con el color. */
:root {
  --fl-1: #2B6E80;
  --fl-2: #3B5E8C;
  --fl-3: #5A5E8E;
  --fl-4: #2F7A63;
  --fl-5: #7A5E4E;
  --fl-6: #4A5560;

  --fl-pane:  #0E2430;          /* aire dentro del depósito */
  --fl-wall:  #8CA6AC;
  --fl-body:  #93A7B2;          /* los cuerpos son todos del mismo gris */
  --fl-body-stroke: #0A1A26;
  --fl-ink:   #D8EAEE;          /* texto sobre un fluido */

  --fl-W: #E4736E;              /* peso */
  --fl-B: #56AEC0;              /* empuje (= --accent) */
  --fl-T: #E8A24A;              /* tensión (= --surge) */
  --fl-N: #9FB4B6;              /* normal del fondo */
  --fl-ok: #6FBF73;
  --fl-bad: #E4736E;
}
@media (prefers-color-scheme: light) {
  :root:not([data-theme]) {
    --fl-1: #9FD4E0;
    --fl-2: #A9C2E6;
    --fl-3: #C0BCE6;
    --fl-4: #A2DCC6;
    --fl-5: #E0C4AC;
    --fl-6: #C3CCD3;

    --fl-pane:  #E4EBEA;
    --fl-wall:  #4C6570;
    --fl-body:  #7C919E;
    --fl-body-stroke: #0C222C;
    --fl-ink:   #16404C;

    --fl-W: #B33F39;
    --fl-B: #1C6B7B;
    --fl-T: #B5670F;
    --fl-N: #5B7178;
    --fl-ok: #2F7A45;
    --fl-bad: #B33F39;
  }
}
:root[data-theme="light"] {
  --fl-ink:   #16404C;
  --fl-1: #9FD4E0;
  --fl-2: #A9C2E6;
  --fl-3: #C0BCE6;
  --fl-4: #A2DCC6;
  --fl-5: #E0C4AC;
  --fl-6: #C3CCD3;

  --fl-pane:  #E4EBEA;
  --fl-wall:  #4C6570;
  --fl-body:  #7C919E;
  --fl-body-stroke: #0C222C;

  --fl-W: #B33F39;
  --fl-B: #1C6B7B;
  --fl-T: #B5670F;
  --fl-N: #5B7178;
  --fl-ok: #2F7A45;
  --fl-bad: #B33F39;
}

/* ---- Escenarios --------------------------------------------------------- */
.preset-list { list-style: none; margin: 0 0 1.4rem; padding: 0; display: grid; gap: 0.35rem; }
.preset-list button {
  width: 100%; text-align: left; cursor: pointer;
  font-family: var(--font-body); font-size: 0.84rem; color: var(--text-dim);
  background: var(--bg-elev); border: 1px solid var(--line);
  border-radius: var(--radius-sm); padding: 0.45rem 0.65rem;
  transition: border-color 0.15s, color 0.15s;
}
.preset-list button:hover { color: var(--text); border-color: var(--accent); }
.preset-list button.is-on { color: var(--accent); border-color: var(--accent); background: var(--sea-fill); }
.preset-list .p-sub { display: block; font-size: 0.72rem; color: var(--text-faint); margin-top: 0.12rem; }
.preset-list button.is-on .p-sub { color: var(--text-dim); }

/* ---- Pestañas ----------------------------------------------------------- */
.fl-tabs {
  display: flex; gap: 0.15rem; margin: 0 0 1rem;
  border-bottom: 1px solid var(--line);
  overflow-x: auto; scrollbar-width: none;
}
.fl-tabs::-webkit-scrollbar { display: none; }
.fl-tabs button {
  font-family: var(--font-mono); font-size: 0.72rem; letter-spacing: 0.04em;
  color: var(--text-faint); background: transparent;
  border: 0; border-bottom: 2px solid transparent;
  padding: 0.45rem 0.6rem; margin-bottom: -1px;
  cursor: pointer; white-space: nowrap;
}
.fl-tabs button:hover { color: var(--text); }
.fl-tabs button[aria-selected="true"] { color: var(--accent); border-bottom-color: var(--accent); }
.fl-tabs button:focus-visible { outline: 2px solid var(--accent); outline-offset: -2px; }
.fl-tabs .n { opacity: 0.6; margin-left: 0.3rem; font-variant-numeric: tabular-nums; }
.fl-panel:focus-visible { outline: none; }

/* ---- Fichas plegables (una capa o un cuerpo) ---------------------------- */
.fl-stack { display: grid; gap: 0.35rem; }
.fl-item {
  border: 1px solid var(--line); border-radius: var(--radius-sm);
  background: var(--bg-elev); overflow: hidden;
}
.fl-item.is-open { border-color: var(--accent); }
.fl-head { display: flex; align-items: stretch; }
/* el resumen es un botón, así que los ↑ ↓ × van FUERA de él: no se pueden
   anidar controles dentro de un <button> */
.fl-sum {
  flex: 1; min-width: 0; display: flex; align-items: center; gap: 0.45rem;
  padding: 0.45rem 0.2rem 0.45rem 0.5rem;
  background: transparent; border: 0; cursor: pointer; text-align: left;
  font-family: var(--font-mono); font-size: 0.73rem; color: var(--text);
}
.fl-sum:hover { background: var(--sea-fill); }
.fl-sum:focus-visible { outline: 2px solid var(--accent); outline-offset: -2px; }
.fl-chev {
  flex: none; width: 0.6rem; color: var(--text-faint);
  transition: transform 0.15s; transform-origin: 50% 50%;
}
.fl-item.is-open .fl-chev { transform: rotate(90deg); }
.fl-swatch {
  width: 0.8rem; height: 0.8rem; border-radius: 3px;
  border: 1px solid var(--line); flex: none;
}
.fl-sum .badge { flex: none; font-weight: 500; color: var(--text); }
.fl-sum .desc {
  flex: 1; min-width: 0; color: var(--text-dim);
  overflow: hidden; text-overflow: ellipsis; white-space: nowrap;
}
.fl-sum .rho { flex: none; color: var(--accent); font-variant-numeric: tabular-nums; }
.fl-sum .link {
  flex: none; font-size: 0.64rem; color: var(--surge);
  border: 1px solid currentColor; border-radius: 3px; padding: 0 0.25rem;
}
.fl-acts { display: flex; align-items: center; gap: 0.15rem; padding: 0 0.4rem 0 0.15rem; }
.fl-mini {
  font-family: var(--font-mono); font-size: 0.72rem; line-height: 1;
  color: var(--text-faint); background: transparent;
  border: 1px solid var(--line); border-radius: 4px;
  padding: 0.18rem 0.34rem; cursor: pointer;
}
.fl-mini:hover:not(:disabled) { color: var(--accent); border-color: var(--accent); }
.fl-mini:disabled { opacity: 0.32; cursor: default; }
.fl-open { padding: 0.15rem 0.6rem 0.65rem; }

.fl-grid { display: grid; gap: 0.45rem 0.6rem; grid-template-columns: 1fr 1fr; }
.fl-grid .wide { grid-column: 1 / -1; }
.fl-field { display: grid; gap: 0.18rem; }
.fl-field > label {
  font-family: var(--font-mono); font-size: 0.66rem; letter-spacing: 0.05em;
  color: var(--text-faint);
}
.fl-field input[type="number"], .fl-field select {
  width: 100%; font-family: var(--font-mono); font-size: 0.78rem;
  color: var(--text); background: var(--bg); border: 1px solid var(--line);
  border-radius: 4px; padding: 0.3rem 0.4rem;
}
.fl-field select { font-family: var(--font-body); font-size: 0.8rem; cursor: pointer; }
.fl-field input:focus-visible, .fl-field select:focus-visible {
  outline: 2px solid var(--accent); outline-offset: 1px;
}
.fl-field .rng { display: flex; align-items: center; gap: 0.5rem; }
.fl-field .rng input[type="range"] { flex: 1; accent-color: var(--accent); height: 1.1rem; cursor: pointer; }
.fl-field .rng .v {
  font-family: var(--font-mono); font-size: 0.72rem; color: var(--accent);
  font-variant-numeric: tabular-nums; min-width: 3.6rem; text-align: right;
}
.fl-note {
  font-family: var(--font-mono); font-size: 0.68rem; color: var(--text-faint);
  margin: 0.4rem 0 0;
}
.fl-note.is-full { color: var(--surge); }

.fl-add {
  width: 100%; margin-top: 0.55rem; cursor: pointer;
  font-family: var(--font-mono); font-size: 0.72rem; letter-spacing: 0.04em;
  color: var(--text-dim); background: transparent;
  border: 1px dashed var(--line); border-radius: var(--radius-sm);
  padding: 0.45rem;
}
.fl-add:hover:not(:disabled) { color: var(--accent); border-color: var(--accent); }
.fl-add:disabled { opacity: 0.35; cursor: default; }

/* ---- Aviso -------------------------------------------------------------- */
.fl-warn {
  margin-top: 0.8rem; padding: 0.5rem 0.7rem;
  border: 1px solid var(--surge); border-left-width: 3px;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  background: var(--bg-elev);
  font-size: 0.8rem; color: var(--text-dim);
}
.fl-warn[hidden] { display: none; }

/* ---- Botonera principal -------------------------------------------------- */
.fl-actions {
  display: flex; gap: 0.5rem; margin: 0 0 1rem; flex-wrap: wrap;
  align-items: center; justify-content: center;
}
.fl-play {
  font-family: var(--font-mono); font-size: 0.8rem; letter-spacing: 0.04em;
  color: var(--on-accent); background: var(--accent);
  border: 1px solid var(--accent); border-radius: var(--radius-sm);
  padding: 0.5rem 1.1rem; cursor: pointer; font-weight: 500;
}
.fl-play:hover:not(:disabled) { background: var(--accent-strong); border-color: var(--accent-strong); }
.fl-play:disabled { opacity: 0.5; cursor: default; }

/* ---- Depósito ----------------------------------------------------------- */
/* La figura NO puede ser `sticky`: un elemento pegajoso se desplaza sin
   reservar sitio, así que al deslizarse acabaría montándose encima de la
   tarjeta de resultados, que va justo debajo en el flujo normal. */
.fl-svg {
  width: 100%; height: auto; display: block;
  max-height: 68vh; margin-inline: auto;
  touch-action: pan-y;   /* el arrastre vertical del cuerpo lo gestiona el JS */
}
.fl-svg .grab { cursor: grab; }
.fl-svg .grab:active { cursor: grabbing; }
.fig-caption {
  font-family: var(--font-mono); font-size: 0.68rem; color: var(--text-faint);
  text-align: center; margin: 0.5rem 0 0;
}
.fig-legend {
  list-style: none; margin: 0.7rem 0 0; padding: 0;
  display: flex; flex-wrap: wrap; justify-content: center; gap: 0.4rem 1rem;
  font-family: var(--font-mono); font-size: 0.68rem; color: var(--text-faint);
}
.fig-legend li { display: inline-flex; align-items: center; gap: 0.35rem; }
.fig-legend .sw { width: 0.9rem; height: 0; border-top: 2px solid currentColor; }
.fig-legend .sw-W { color: var(--fl-W); }
.fig-legend .sw-B { color: var(--fl-B); }
.fig-legend .sw-T { color: var(--fl-T); }
.fig-legend .sw-N { color: var(--fl-N); }

/* ---- Panel de resultados ------------------------------------------------ */
.fl-results { margin-top: 1.8rem; display: grid; gap: 0.8rem; }
@media (min-width: 40rem) { .fl-results { grid-template-columns: 1fr 1fr; } }
.fl-res {
  border: 1px solid var(--line); border-radius: var(--radius-sm);
  background: var(--bg-elev); padding: 0.7rem 0.85rem;
}
.fl-res-head {
  display: flex; align-items: baseline; gap: 0.5rem; margin-bottom: 0.5rem;
  font-family: var(--font-mono); font-size: 0.7rem; letter-spacing: 0.08em;
  text-transform: uppercase; color: var(--text-faint);
}
.fl-res-head .st { margin-left: auto; text-transform: none; letter-spacing: 0; color: var(--accent); }
.fl-res dl { margin: 0; display: grid; gap: 0.15rem 0.8rem; grid-template-columns: 1fr auto; }
.fl-res dt { font-size: 0.78rem; color: var(--text-dim); }
.fl-res dd {
  margin: 0; font-family: var(--font-mono); font-size: 0.78rem; color: var(--text);
  font-variant-numeric: tabular-nums; text-align: right;
}
.fl-res dd.hi { color: var(--accent); }
/* desglose del reparto por fluidos: secundario respecto a la fila que resume */
.fl-res dt.sub, .fl-res dd.sub { font-size: 0.72rem; color: var(--text-faint); }
.fl-res dt.sub { padding-left: 0.25rem; }
.fl-res .veil { font-family: var(--font-mono); font-size: 0.76rem; color: var(--text-faint); }

.fl-pred { margin-top: 0.6rem; padding-top: 0.55rem; border-top: 1px solid var(--line-soft); }
.fl-pred label { font-size: 0.76rem; color: var(--text-dim); display: block; margin-bottom: 0.25rem; }
.fl-pred .row { display: flex; align-items: center; gap: 0.4rem; }
.fl-pred input[type="number"] {
  width: 5rem; font-family: var(--font-mono); font-size: 0.78rem;
  color: var(--text); background: var(--bg); border: 1px solid var(--line);
  border-radius: 4px; padding: 0.25rem 0.35rem;
}
.fl-verdict { font-family: var(--font-mono); font-size: 0.76rem; margin-top: 0.35rem; }
.fl-verdict.ok { color: var(--fl-ok); }
.fl-verdict.bad { color: var(--fl-bad); }

/* ---- §3 Balance de fuerzas ---------------------------------------------- */
.eq-list { display: grid; gap: 0.9rem; margin-top: 1.4rem; }
.eq-item {
  border: 1px solid var(--line); border-left: 3px solid var(--accent);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  background: var(--bg-elev); padding: 0.75rem 1rem;
  overflow-x: auto;
}
.eq-item h3 {
  font-family: var(--font-mono); font-size: 0.68rem; letter-spacing: 0.09em;
  text-transform: uppercase; color: var(--text-faint);
  margin: 0 0 0.5rem; font-weight: 500;
}
.eq-item .eq-body { color: var(--text-dim); font-size: 0.92rem; }
.eq-item .eq-body p { margin: 0 0 0.45rem; }
.eq-item .eq-body p:last-child { margin-bottom: 0; }
.eq-veil { color: var(--text-faint); font-family: var(--font-mono); font-size: 0.8rem; }