/* loop-scene.css — styles for the closed-loop charge-flow visual (LoopScene)
   and its wrappers (the standalone Flow Lab + the Chapter 1 embedded section). */

.lab { width: 100%; max-width: 980px; }
.lab-eyebrow {
  font-family: 'IBM Plex Mono', monospace; font-size: 11px; letter-spacing: 0.18em;
  text-transform: uppercase; color: var(--ink-faint); margin-bottom: 14px;
}
.lab-head h1 {
  font-family: 'Newsreader', serif; font-weight: 400; letter-spacing: -0.02em;
  font-size: clamp(32px, 5vw, 52px); line-height: 1.02; margin: 0 0 16px; color: var(--ink);
}
.lab-head h1 em { font-style: italic; color: var(--current); }
.lab-lede { font-size: 16px; line-height: 1.64; color: var(--ink-soft); max-width: 48em; margin: 0 0 26px; }
.lab-lede b { color: var(--ink); font-weight: 500; }
.fl-explain { display: flex; flex-direction: column; gap: 5px; margin: 14px 0 0; padding: 13px 16px; background: var(--bg-card); border: 1px solid var(--rule); border-radius: 10px; }
.fl-explain span { font-size: 13.5px; line-height: 1.5; color: var(--ink-soft); }
.fl-explain b { font-weight: 600; }
.fl-bright { color: var(--water); font-weight: 600; }
.fl-dim { color: var(--ink-faint); font-weight: 600; }

.lab-stage { background: var(--bg-card); border: 1px solid var(--rule); border-radius: 12px; padding: 6px; position: relative; }
.lab-canvas { display: block; width: 100%; height: auto; border-radius: 8px; }
.fl-spotbtn {
  position: absolute; left: 50%; bottom: 10px; transform: translateX(-50%);
  appearance: none; cursor: pointer; white-space: nowrap;
  font-family: 'IBM Plex Mono', monospace; font-size: 12px; letter-spacing: 0.04em;
  padding: 6px 14px; border-radius: 999px;
  background: var(--bg-card); color: var(--ink-soft); border: 1px solid var(--rule-strong);
  transition: all .15s ease; box-shadow: 0 1px 4px rgba(0,0,0,0.06);
}
.fl-spotbtn:hover { border-color: var(--current); color: var(--ink); }
.fl-spotbtn.on { background: var(--current); color: #fff; border-color: var(--current); }

.fl-modebar { display: flex; align-items: center; gap: 18px; margin-top: 14px; flex-wrap: wrap; }
.fl-seg { display: inline-flex; background: var(--bg-deeper); border: 1px solid var(--rule); border-radius: 10px; padding: 3px; flex: 0 0 auto; }
.fl-seg button {
  appearance: none; border: 0; cursor: pointer; background: transparent;
  font-family: 'IBM Plex Mono', monospace; font-size: 13px; letter-spacing: 0.04em;
  color: var(--ink-soft); padding: 7px 16px; border-radius: 8px; transition: all .15s ease;
}
.fl-seg button.on { background: var(--bg-card); color: var(--ink); box-shadow: 0 1px 3px rgba(0,0,0,0.08); }
.fl-modenote { flex: 1 1 280px; margin: 0; font-size: 13.5px; line-height: 1.5; color: var(--ink-soft); }
.fl-modenote b { color: var(--ink); font-weight: 600; }
.fl-modenote i { color: var(--current); font-style: italic; }

.lab-readouts {
  display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 1px;
  background: var(--rule); border: 1px solid var(--rule); border-radius: 10px; overflow: hidden; margin-top: 12px;
}
.ro { background: var(--bg-card); padding: 9px 12px; display: flex; flex-direction: column; gap: 4px; }
.ro-name { font-family: 'IBM Plex Mono', monospace; font-size: 9.5px; letter-spacing: 0.1em; text-transform: uppercase; color: var(--ink-faint); }
.ro-val { font-family: 'Newsreader', serif; font-style: italic; font-size: 23px; line-height: 1; color: var(--ink); }
.ro-val i { font-family: 'IBM Plex Mono', monospace; font-style: normal; font-size: 11px; color: var(--ink-faint); margin-left: 3px; }

.lab-controls { display: grid; grid-template-columns: 1fr 1fr; gap: 16px 32px; margin-top: 16px; align-items: start; }
.lab-slider { display: flex; flex-direction: column; gap: 9px; }
.ls-top { display: flex; justify-content: space-between; align-items: baseline; font-size: 15px; color: var(--ink); }
.ls-top i { font-style: normal; color: var(--ink-faint); font-size: 13px; }
.ls-v { font-family: 'IBM Plex Mono', monospace; font-size: 14px; color: var(--ink-soft); }
.ls-hint { font-size: 13px; color: var(--ink-faint); line-height: 1.45; }

.lab-foot { margin-top: 22px; font-size: 14px; line-height: 1.62; color: var(--ink-soft); }
.lab-foot b { color: var(--ink); font-weight: 600; }
.fl-note { display: block; margin-top: 8px; font-size: 13px; color: var(--ink-faint); }
.lab .range { width: 100%; }

@media (max-width: 620px) {
  /* compact 4-up readout row + smaller spot button so the visual, not the
     chrome, owns the small screen */
  .lab-stage { padding: 4px; }
  .lab-readouts { grid-template-columns: repeat(4, minmax(0, 1fr)); margin-top: 8px; }
  .ro { padding: 6px 7px; gap: 3px; }
  .ro-name { font-size: 8px; letter-spacing: 0.06em; }
  .ro-val { font-size: 15px; }
  .ro-val i { font-size: 9px; margin-left: 2px; }
  .lab-controls { grid-template-columns: 1fr; margin-top: 10px; gap: 12px; }
  .fl-spotbtn { font-size: 9.5px; padding: 4px 9px; bottom: 6px; box-shadow: none; }
  .fl-seg button { font-size: 11.5px; padding: 6px 11px; }
}