/* The microscope room, and the walk into it.
   Dark palette from docs/style-guide.md §2. Channel colours are validated
   together on --scope; if one changes, re-run the dataviz validator. */

/* --------------------------------------------------------------- primers */

.primers {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 18px;
  margin: 32px auto;
}
.primer {
  background: var(--card);
  border: 1px solid var(--rule);
  border-radius: 16px;
  padding: 20px 22px;
}
.primer h3 { font-size: 20px; margin-bottom: 8px; color: var(--tissue); }
.primer p { font-size: 15.5px; color: var(--ink-soft); margin: 0; }

/* --------------------------------------- step up to the microscope (guide §5)
   A full screen of scroll from daylight into the dark. It carries no meaning,
   so it is hidden from assistive technology. */

.step {
  position: relative;
  height: 60vh;
  min-height: 320px;
  background: linear-gradient(var(--paper) 0%, #cdbdb0 32%, #2a2d3a 72%, var(--scope) 100%);
}
.step-cue {
  position: absolute; left: 0; right: 0; bottom: 96px;
  text-align: center;
  color: #e8edf6;
  font: 500 13px/1 var(--text);
  letter-spacing: .14em;
  text-transform: uppercase;
  opacity: .8;
  margin: 0;
}
.step-ring {
  position: absolute; left: 50%; bottom: -64px;
  width: 128px; height: 128px; margin-left: -64px;
  border-radius: 50%;
  border: 2px solid rgba(232, 237, 246, .32);
  box-shadow: 0 0 0 10px rgba(232, 237, 246, .05),
              inset 0 0 40px rgba(127, 212, 255, .14);
}

/* ------------------------------------------------------------- the dark room */

.hall {
  background: var(--scope);
  color: var(--scope-ink);
  padding: 112px 0 96px;
}
.hall .hall-head { text-align: center; margin-bottom: 64px; }
.hall .hall-head h2 { font-size: clamp(34px, 5.5vw, 56px); }
.hall .hall-head p { color: var(--scope-soft); max-width: 36em; margin: 16px auto 0; font-size: 19px; }
.hall .kicker { color: #6fe3d0; }

.station {
  max-width: var(--wide);
  margin: 0 auto;
  padding: 56px var(--gutter);
  border-top: 1px solid rgba(232, 237, 246, .12);
}
.station:first-of-type { border-top: 0; }
.station h3 { font-size: clamp(26px, 3.6vw, 36px); margin-bottom: 14px; }
.station-lead { color: var(--scope-soft); max-width: 46ch; font-size: 18px; margin-bottom: 4px; }

.hall figcaption, .hall .honesty { color: var(--scope-soft); }

.hall .exhibit-controls button {
  background: var(--scope-2);
  border-color: rgba(232, 237, 246, .22);
  color: var(--scope-ink);
}
.hall .exhibit-controls button:hover { background: #1e273c; }
.hall .exhibit-controls button[aria-pressed="true"] {
  border-color: #6fe3d0;
  color: #bdf4ea;
}
.hall .exhibit-controls .hint { color: var(--scope-soft); }

/* placards keep the paper feel inside the dark room: the reading surface does
   not change just because the exhibit is lit differently */
.hall .placard { background: var(--scope-2); border-color: rgba(232, 237, 246, .14); }
.hall .placard-depths { border-bottom-color: rgba(232, 237, 246, .14); }
.hall .placard-depths button { color: var(--scope-soft); }
.hall .placard-depths button:hover { background: #1e273c; }
.hall .placard-depths button[aria-selected="true"] {
  background: rgba(111, 227, 208, .14);
  border-color: #6fe3d0;
  color: #eafaf7;
}
.hall .placard-body > div > h4 { color: var(--scope-soft); }
.hall .chips li {
  background: rgba(232, 237, 246, .07);
  border-color: rgba(232, 237, 246, .18);
  color: var(--scope-soft);
}


/* drag affordance on the exhibits that hand over control (guide §5) */
.plate [data-rail] svg[data-ex] { cursor: grab; }
.plate[data-grabbing="true"] [data-rail] svg[data-ex] { cursor: grabbing; }

@media (max-width: 720px) {
  .station { padding: 40px var(--gutter); }
  .step { height: 46vh; }
}

/* The global focus ring is the daylight teal, which sits at about 2:1 on the
   dark plates — a keyboard user would lose track of where they are. The dark
   rooms get their own ring. */
.hall :focus-visible,
.plate :focus-visible {
  outline: 3px solid #7af0da;
  outline-offset: 3px;
}