/* ==========================================================================
   Interactive mechanism explorer.
   One stage, two acts (high-level / low-level), switchable across tasks.
   Sizing is container-relative so the whole diagram scales as one object.
   ========================================================================== */

.mech-act {
  --mech-gap: 3.2cqw;
  --card-radius: 0.85cqw;
}

.mech-toolbar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 14px;
  margin-top: 28px;
}

.mech-toolbar-label {
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--muted);
}

.mech-spacer { flex: 1 1 24px; }

/* --- stage --------------------------------------------------------------- */

.mech-stage {
  container-type: inline-size;
  container-name: mech;
  position: relative;
  margin-top: 20px;
  padding: clamp(18px, 2.6cqw, 40px);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
  box-shadow: var(--shadow-card);
}

.mech-act {
  display: none;
  position: relative;
}
.mech-act.is-current { display: block; }

.mech-links {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  overflow: visible;
  pointer-events: none;
  z-index: 2;
}
.mech-links path { fill: none; }
.mech-links .link-track {
  stroke: var(--line);
  stroke-width: 1.5;
}
.mech-links .link-pulse {
  stroke: var(--flow);
  stroke-width: 2;
  stroke-linecap: round;
  stroke-dasharray: 18 82;
  animation: mech-pulse 1.9s linear infinite;
  opacity: 0;
  transition: opacity 0.35s ease;
}
.mech-links .link-pulse.is-live { opacity: 1; }
@keyframes mech-pulse { to { stroke-dashoffset: -100; } }

.mech-node {
  position: relative;
  z-index: 3;
  margin: 0;
  min-width: 0;
}

.mech-label {
  margin: 0 0 0.7cqw;
  font-size: clamp(10px, 1.05cqw, 13px);
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--muted);
}

/* --- act 1: human signal -> high-level policy -> subtask queue ----------- */

.mech-act-high {
  display: none;
  grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.78fr) minmax(0, 1.12fr);
  align-items: center;
  gap: var(--mech-gap);
}
.mech-act-high.is-current { display: grid; }

.mech-signal-frame {
  position: relative;
  border: 1px solid var(--line);
  border-radius: var(--card-radius);
  overflow: hidden;
  background: #000;
  aspect-ratio: 1 / 1;
  transition: box-shadow 0.35s ease, border-color 0.35s ease;
}
.mech-signal-frame video {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.mech-signal-frame.is-firing {
  border-color: var(--accent);
  box-shadow: 0 0 0 4px color-mix(in srgb, var(--accent) 18%, transparent);
}

.mech-glasses-badge {
  position: absolute;
  left: 0.7cqw;
  top: 0.7cqw;
  display: flex;
  align-items: center;
  gap: 0.5cqw;
  padding: 0.4cqw 0.7cqw 0.4cqw 0.4cqw;
  border-radius: 999px;
  background: rgba(10, 12, 18, 0.62);
  backdrop-filter: blur(6px);
  color: #fff;
  font-size: clamp(8px, 0.92cqw, 11px);
  font-weight: 550;
  letter-spacing: 0.02em;
}
.mech-glasses-badge img {
  width: clamp(16px, 1.9cqw, 26px);
  height: clamp(16px, 1.9cqw, 26px);
  border-radius: 50%;
  object-fit: cover;
}

.mech-asr {
  margin-top: 1cqw;
  padding: 1cqw 1.2cqw;
  min-height: 4.6cqw;
  border: 1px solid var(--accent-border);
  border-radius: var(--card-radius);
  background: var(--accent-soft);
  color: var(--accent-ink);
  font-size: clamp(11px, 1.3cqw, 16px);
  line-height: 1.45;
  font-weight: 550;
}
.mech-asr small {
  display: block;
  margin-bottom: 0.25cqw;
  font-size: clamp(8px, 0.85cqw, 10px);
  font-weight: 700;
  letter-spacing: 0.14em;
  color: color-mix(in srgb, var(--accent-ink) 62%, transparent);
}
.mech-asr .mech-asr-text::after {
  content: "";
  display: inline-block;
  width: 0.09em;
  height: 1em;
  margin-left: 0.08em;
  vertical-align: -0.14em;
  background: currentColor;
  animation: mech-caret 1s steps(1) infinite;
}
.mech-asr.is-idle .mech-asr-text::after { display: none; }
@keyframes mech-caret { 50% { opacity: 0; } }

/* engine boxes (pi_h / pi_l) */

.mech-engine {
  display: grid;
  gap: 0.35cqw;
  padding: 1.5cqw 1.2cqw;
  border: 1px solid var(--accent-border);
  border-radius: var(--card-radius);
  background: var(--accent-soft);
  text-align: center;
  transition: box-shadow 0.3s ease, transform 0.3s ease;
}
.mech-engine h3 {
  margin: 0;
  font-size: clamp(12px, 1.5cqw, 19px);
  font-weight: 650;
  letter-spacing: -0.02em;
  color: var(--ink);
}
.mech-engine p {
  margin: 0;
  font-size: clamp(10px, 1.15cqw, 14px);
  color: var(--accent-ink);
  font-weight: 550;
}
.mech-engine.is-firing {
  box-shadow: 0 0 0 5px color-mix(in srgb, var(--accent) 14%, transparent);
}

.mech-engine-note {
  margin: 0.9cqw 0 0;
  font-size: clamp(9.5px, 1.05cqw, 13px);
  line-height: 1.45;
  color: var(--muted);
  text-align: center;
}

/* subtask queue */

.mech-queue h3 {
  margin: 0 0 0.8cqw;
  font-size: clamp(11px, 1.25cqw, 15px);
  font-weight: 650;
  letter-spacing: -0.01em;
}
.mech-queue h3 span {
  margin-left: 0.5em;
  font-weight: 450;
  color: var(--muted);
}

.mech-cards {
  display: grid;
  gap: 0.8cqw;
  min-height: 12cqw;
  align-content: start;
}

.mech-card {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  align-items: center;
  gap: 1cqw;
  padding: 0.6cqw;
  border: 1px solid var(--line);
  border-radius: var(--card-radius);
  background: var(--surface-2);
  text-align: left;
  width: 100%;
  transition: border-color 0.3s ease, box-shadow 0.3s ease, opacity 0.3s ease;
}

/* Only cards that appear live animate in: a fill-mode entrance would pin
   opacity:0 on cards built while their act is still display:none. */
.mech-card.is-new { animation: mech-card-in 0.45s cubic-bezier(0.22, 1, 0.36, 1); }
@keyframes mech-card-in {
  from { opacity: 0; transform: translateY(0.9cqw) scale(0.985); }
  to   { opacity: 1; transform: none; }
}

.mech-card img {
  display: block;
  width: clamp(48px, 6.4cqw, 104px);
  aspect-ratio: 1 / 1;
  object-fit: cover;
  border-radius: calc(var(--card-radius) - 0.25cqw);
  background: var(--line-soft);
}
.mech-card small {
  display: block;
  font-size: clamp(8px, 0.88cqw, 11px);
  font-weight: 700;
  letter-spacing: 0.12em;
  color: var(--muted);
}
.mech-card h4 {
  margin: 0.25cqw 0 0;
  font-size: clamp(10.5px, 1.2cqw, 15px);
  font-weight: 550;
  line-height: 1.35;
  letter-spacing: -0.015em;
  color: var(--ink);
}

.mech-card-state {
  grid-column: 1 / -1;
  display: none;
  align-items: center;
  gap: 0.45em;
  font-size: clamp(8.5px, 0.95cqw, 11.5px);
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}
.mech-act-low .mech-card-state { display: flex; }

.mech-card.is-active {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--accent) 15%, transparent);
}
.mech-card.is-active .mech-card-state { color: var(--accent-ink); }
.mech-card.is-done .mech-card-state { color: var(--ok); }
.mech-card.is-pending { opacity: 0.55; }
.mech-card.is-pending .mech-card-state { color: var(--muted); }

.mech-queue-empty {
  display: grid;
  place-items: center;
  min-height: 12cqw;
  border: 1px dashed var(--line);
  border-radius: var(--card-radius);
  font-size: clamp(10px, 1.1cqw, 13px);
  color: var(--muted);
}

/* --- act 2: queue -> low-level policy -> action ------------------------- */

.mech-act-low { display: none; }
.mech-act-low.is-current { display: block; }

.mech-act-low .mech-queue { margin-bottom: calc(var(--mech-gap) * 1.15); }
.mech-act-low .mech-cards {
  grid-auto-flow: column;
  grid-auto-columns: minmax(0, 1fr);
  min-height: 0;
}

.mech-exec {
  display: grid;
  grid-template-columns: minmax(0, 1.15fr) minmax(0, 0.72fr) minmax(0, 0.92fr);
  align-items: center;
  gap: var(--mech-gap);
}

.mech-obs {
  border: 1px solid var(--line);
  border-radius: var(--card-radius);
  overflow: hidden;
  background: #000;
  aspect-ratio: 16 / 9;
}
.mech-obs video { display: block; width: 100%; height: 100%; object-fit: contain; }

.mech-output {
  display: grid;
  gap: 0.8cqw;
}

.mech-readout {
  padding: 0.9cqw 1.1cqw;
  border: 1px solid var(--line);
  border-radius: var(--card-radius);
  background: var(--surface-2);
}
.mech-readout p {
  margin: 0 0 0.35cqw;
  font-size: clamp(9.5px, 1.05cqw, 13px);
  font-weight: 600;
  color: var(--muted);
}
.mech-readout code {
  display: block;
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
  font-size: clamp(9px, 1.02cqw, 12.5px);
  font-variant-numeric: tabular-nums;
  letter-spacing: -0.02em;
  color: var(--ink);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.mech-readout .mech-completion {
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
  font-size: clamp(14px, 1.9cqw, 24px);
  font-weight: 700;
  font-variant-numeric: tabular-nums;
  color: var(--muted);
  transition: color 0.2s ease;
}
.mech-readout .mech-completion.is-complete { color: var(--ok); }

.mech-note {
  margin: 0.55cqw 0 0;
  font-size: clamp(8.5px, 0.92cqw, 11px);
  line-height: 1.4;
  color: var(--muted);
}

/* --- act rail and transport --------------------------------------------- */

.mech-acts {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0 0 22px;
  padding: 0;
  list-style: none;
}

.mech-acts button {
  display: flex;
  align-items: baseline;
  gap: 8px;
  padding: 9px 15px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: var(--surface);
  font-size: 13.5px;
  font-weight: 550;
  color: var(--muted);
  transition: all 0.2s ease;
}
.mech-acts button b {
  font-size: 11px;
  font-weight: 700;
  color: var(--muted);
}
.mech-acts button:hover { color: var(--ink); border-color: var(--accent-border); }
.mech-acts button[aria-selected="true"] {
  border-color: var(--accent);
  background: var(--accent-soft);
  color: var(--accent-ink);
}
.mech-acts button[aria-selected="true"] b { color: var(--accent); }

.mech-transport {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-top: 18px;
}

.mech-progress {
  position: relative;
  flex: 1;
  height: 4px;
  cursor: pointer;
  touch-action: none;
  border-radius: 999px;
  background: var(--line-soft);
}

/* A taller hit area than the 4px bar, without adding an in-flow box that
   would push the fill out of the track. */
.mech-progress::after {
  content: "";
  position: absolute;
  inset: -9px 0;
}

.mech-progress i {
  overflow: hidden;
}
.mech-progress i {
  display: block;
  height: 100%;
  width: 0%;
  border-radius: inherit;
  background: var(--accent);
}

.mech-caption {
  margin: 16px 0 0;
  font-size: clamp(13px, 1.3vw, 15.5px);
  line-height: 1.6;
  color: var(--ink-soft);
}
.mech-caption strong { font-weight: 600; color: var(--ink); }

/* --- narrow layouts ------------------------------------------------------ */

@container mech (max-width: 720px) {
  .mech-act { --mech-gap: 20px; --card-radius: 10px; }

  .mech-act-high.is-current,
  .mech-exec {
    grid-template-columns: minmax(0, 1fr);
  }

  .mech-links { display: none; }

  /* `* + *` would also catch the (hidden) connector svg and draw a stub above
     the first real node, so the stems hang off .mech-node siblings only. */
  .mech-act-high.is-current > .mech-node ~ .mech-node,
  .mech-exec > .mech-node ~ .mech-node {
    position: relative;
  }
  .mech-act-high.is-current > .mech-node ~ .mech-node::before,
  .mech-exec > .mech-node ~ .mech-node::before {
    content: "";
    position: absolute;
    left: 50%;
    top: calc(var(--mech-gap) * -1);
    width: 1px;
    height: var(--mech-gap);
    background: var(--line);
  }

  .mech-act-low .mech-cards {
    grid-auto-flow: row;
    grid-auto-columns: auto;
  }

  .mech-label,
  .mech-asr small,
  .mech-card small,
  .mech-card-state { font-size: 10px; }
  .mech-asr { font-size: 14px; padding: 11px 13px; min-height: 0; }
  .mech-engine { padding: 14px 12px; }
  .mech-engine h3 { font-size: 16px; }
  .mech-engine p, .mech-engine-note { font-size: 13px; }
  .mech-card { padding: 8px; gap: 12px; }
  .mech-card h4 { font-size: 14px; }
  .mech-card img { width: 64px; }
  .mech-queue h3 { font-size: 14px; margin-bottom: 10px; }
  .mech-cards { gap: 10px; min-height: 0; }
  .mech-readout { padding: 11px 13px; }
  .mech-readout p { font-size: 12px; }
  .mech-readout code { font-size: 11.5px; white-space: normal; }
  .mech-readout .mech-completion { font-size: 22px; }
  .mech-note { font-size: 11px; margin-top: 8px; }
}