/* ═══════════════════════════════════════════════════════════════════
   CONNECT 4 — THE LAB
   style.css

   Section map:
     1. Reset & base
     2. Lab background   (copied verbatim from global CSS)
     3. Lab structural UI (copied verbatim from global CSS)
     4. Status bar
     5. Main two-column layout
     6. Game section — column indicators
     7. Game section — board & pieces
     8. Game section — controls & legend
     9. Visualizer section — header & stats
    10. Visualizer section — event log
    11. Footer
    12. Visualizer section — difficulty controls
═══════════════════════════════════════════════════════════════════ */


/* ═══════════════════════════════════════════════
   1. RESET & BASE
   ═══════════════════════════════════════════════ */

*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html, body {
  background-color: #fafafa;
  /* monospace as the document default keeps inline fallback text on-theme */
  font-family: 'Courier New', monospace;
}


/* ═══════════════════════════════════════════════
   2. LAB BACKGROUND  (from global CSS — unchanged)
   ═══════════════════════════════════════════════ */

.grid-bg {
  min-height: 100vh;
  background-color: #fafafa;
  background-image:
    linear-gradient(rgba(0,0,0,0.06) 1px, transparent 1px),
    linear-gradient(90deg, rgba(0,0,0,0.06) 1px, transparent 1px),
    linear-gradient(rgba(0,0,0,0.12) 1px, transparent 1px),
    linear-gradient(90deg, rgba(0,0,0,0.12) 1px, transparent 1px);
  background-size: 20px 20px, 20px 20px, 100px 100px, 100px 100px;
  animation: grid-drift 120s linear infinite;
  position: relative;
}

@keyframes grid-drift {
  0%   { background-position: 0 0, 0 0, 0 0, 0 0; }
  100% { background-position: 8px 8px, 12px 12px, 30px 30px, 45px 45px; }
}

/* Grain overlay */
.grid-bg::before {
  content: '';
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image: radial-gradient(rgba(0,0,0,0.02) 1px, transparent 1px);
  background-size: 3px 3px;
  opacity: 0.18;
  mix-blend-mode: multiply;
}

/* Scanline flicker */
.grid-bg::after {
  content: '';
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image: linear-gradient(rgba(0,0,0,0.02) 1px, transparent 1px);
  background-size: 100% 3px;
  opacity: 0.03;
  animation: scanline-flicker 10s steps(1, end) infinite;
}

@keyframes scanline-flicker {
  0%   { opacity: 0.02; }
  4%   { opacity: 0.04; }
  6%   { opacity: 0.01; }
  100% { opacity: 0.02; }
}


/* ═══════════════════════════════════════════════
   3. LAB STRUCTURAL UI  (from global CSS — unchanged)
   ═══════════════════════════════════════════════ */

.lab-page {
  min-height: 100vh;
  display: flex;
  align-items: flex-start;
  justify-content: center;
  padding: 3rem 1rem 5rem;
}

/* Widened to accommodate the side-by-side layout */
.lab-panel {
  background: #fff;
  border: 1px solid #1a1a1a;
  max-width: 1100px;
  width: 100%;
}

.lab-header {
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: 1rem;
  padding: 0.85rem 1rem;
}

.lab-header-center { text-align: center; }

.lab-eyebrow {
  font-family: 'Courier New', monospace;
  font-size: 0.65rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: #999;
  margin-bottom: 0.2rem;
}

.lab-title {
  font-family: 'Times New Roman', serif;
  font-size: clamp(1.6rem, 4vw, 2.4rem);
  font-weight: 900;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: #1a1a1a;
  line-height: 1;
}

.lab-rule {
  width: 100%;
  height: 1px;
  background: #1a1a1a;
}

.lab-btn {
  font-family: 'Courier New', monospace;
  font-size: 0.62rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: #1a1a1a;
  text-decoration: none;
  border: 1px solid #1a1a1a;
  padding: 0.3rem 0.6rem;
  white-space: nowrap;
  background: transparent;
  cursor: pointer;
  transition: background 140ms ease, color 140ms ease;
  display: inline-block;
}

.lab-btn:hover {
  background: #1a1a1a;
  color: #fff;
}

/* Persistent "selected" state — same as hover but doesn't require hover.
   Applied to whichever difficulty preset is currently active. */
.lab-btn--active {
  background: #1a1a1a;
  color: #fff;
}

.lab-help-btn {
  font-family: 'Courier New', monospace;
  font-size: 0.75rem;
  font-weight: 700;
  color: #1a1a1a;
  background: transparent;
  border: 1px solid #1a1a1a;
  width: 28px;
  height: 28px;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background 140ms ease, color 140ms ease;
}

.lab-help-btn:hover {
  background: #1a1a1a;
  color: #fff;
}


/* ═══════════════════════════════════════════════
   4. STATUS BAR
   Sits between the header rule and the main area.
   ═══════════════════════════════════════════════ */

.lab-status-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.45rem 1rem;
  background: #fafafa;
}

.lab-label {
  font-family: 'Courier New', monospace;
  font-size: 0.58rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: #999;
}

.lab-status-text {
  font-family: 'Courier New', monospace;
  font-size: 0.72rem;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: #1a1a1a;
  font-weight: 700;
}


/* ═══════════════════════════════════════════════
   5. MAIN TWO-COLUMN LAYOUT
   Left: game board  |  Right: visualizer
   ═══════════════════════════════════════════════ */

.lab-main {
  display: grid;
  /* Fixed 380px visualizer column; game board takes the rest */
  grid-template-columns: 1fr 380px;
  min-height: 520px;
}


/* ═══════════════════════════════════════════════
   6. GAME SECTION — COLUMN INDICATORS
   Row of 7 invisible buttons above the board.
   Hovering one shows a ▼ caret; clicking drops a piece.
   ═══════════════════════════════════════════════ */

.game-section {
  padding: 1.5rem;
  border-right: 1px solid #1a1a1a;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.75rem;
}

/* Container aligns to the board's max-width */
.col-indicators {
  display: grid;
  grid-template-columns: repeat(7, 1fr);
  width: 90%;
}

.col-indicator {
  background: transparent;
  border: none;
  border-bottom: 2px solid transparent;
  cursor: pointer;
  padding: 0.35rem 0;
  text-align: center;
  transition: border-color 80ms ease;
}

/* The drop caret — hidden by default, shown on hover/focus */
.col-indicator::after {
  content: '▼';
  display: block;
  font-size: 0.55rem;
  color: transparent;
  transition: color 80ms ease;
  line-height: 1;
}

.col-indicator:hover::after,
.col-indicator:focus-visible::after,
.col-indicator--hover::after {
  color: #1a1a1a;
}

.col-indicator:hover,
.col-indicator--hover {
  border-bottom-color: #1a1a1a;
}

/* Disabled: no pointer, no caret */
.col-indicator:disabled {
  cursor: not-allowed;
  border-bottom-color: transparent !important;
}

.col-indicator:disabled::after {
  color: transparent !important;
}


/* ═══════════════════════════════════════════════
   7. GAME SECTION — BOARD & PIECES
   The 6×7 grid of cells. Each cell contains one
   .piece div (the circle). Pieces are styled via
   modifier classes applied by ui.js.
   ═══════════════════════════════════════════════ */

.board {
  display: grid;
  grid-template-columns: repeat(7, 1fr);
  grid-template-rows: repeat(6, 1fr);
  /* Outer edge matches the panel's black border language */
  border: 1px solid #1a1a1a;
  width: 90%;
  /* #fafafa bleeds through as the cell-gap "lines" */
  background: #e8e8e8;
  gap: 1px;
}

.board-cell {
  aspect-ratio: 1;
  background: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 7px;
  cursor: pointer;
  /* No transition needed — the .piece inside animates */
}

/* Column hover: cells tint when the indicator above is hovered.
   Class is toggled by UI.highlightColumn(). */
.board-cell.col-hover {
  background: #f4f4f4;
}

/* ── The circle inside each cell ── */
.piece {
  width: 100%;
  height: 100%;
  border-radius: 50%;       /* circles only — the rest of the UI is angular */
  border: 1px solid #ddd;   /* empty state: faint ring */
  background: transparent;
  transition: background 100ms ease, border-color 100ms ease;
}

/* Player 1 (human): solid black */
.piece--player {
  background: #1a1a1a;
  border-color: #1a1a1a;
}

/* Player 2 (AI): dark clinical red */
.piece--ai {
  background: #b91c1c;
  border-color: #b91c1c;
}

/* Winning cells: white inset ring drawn over the filled piece */
.piece--win {
  box-shadow: inset 0 0 0 3px rgba(255,255,255,0.75);
}

/* Drop animation: piece "lands" with a brief scale pop */
@keyframes piece-drop {
  0%   { transform: scale(0.45); opacity: 0.5; }
  65%  { transform: scale(1.1); }
  100% { transform: scale(1);   opacity: 1; }
}

.piece--drop {
  animation: piece-drop 180ms ease-out forwards;
}

/*
  ── PHASE 2 CHEMICAL POUR (saved, not active) ──────────────────────────
  To re-enable: delete the Phase 1 block above and uncomment this block.
  Also uncomment the matching animateDrop() in ui.js.

.board {
  display: grid;
  grid-template-columns: repeat(7, 1fr);
  grid-template-rows: repeat(6, 1fr);
  border: 1px solid #1a1a1a;
  width: 100%;
  max-width: 430px;
  column-gap: 1px;
  row-gap: 0;
  background: #1a1a1a;
}

.board-cell {
  aspect-ratio: 1;
  background: #fff;
  position: relative;
  overflow: hidden;
}

.board-cell.col-hover {
  background: #f5f5f5;
}

.piece {
  position: absolute;
  inset: 0;
  background: transparent;
  transform: scaleY(0);
  transform-origin: bottom;
}

.piece--player {
  background: #000000;
  transform: scaleY(1);
}

.piece--ai {
  background: #ff0000;
  transform: scaleY(1);
}

.piece--win {
  outline: 2px solid rgba(255, 255, 255, 0.9);
  outline-offset: -5px;
}

.piece--fill {
  transition: transform 280ms ease-in;
}
  ── END PHASE 2 CHEMICAL POUR ──────────────────────────────────────── */


/* ═══════════════════════════════════════════════
   8. GAME SECTION — CONTROLS & LEGEND
   ═══════════════════════════════════════════════ */

.game-controls {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 90%;
}

.lab-legend {
  display: flex;
  gap: 1rem;
  align-items: center;
}

.legend-item {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  font-family: 'Courier New', monospace;
  font-size: 0.58rem;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: #666;
}

.legend-piece {
  width: 13px;
  height: 13px;
  border-radius: 50%;
  flex-shrink: 0;
}

.legend-piece.player-piece { background: #1a1a1a; }
.legend-piece.ai-piece     { background: #b91c1c; }
/* PHASE 2: swap to { background: #000000 } and { background: #ff0000 }
   and remove border-radius when re-enabling chemical pour */


/* ═══════════════════════════════════════════════
   9. VISUALIZER SECTION — HEADER & STATS
   ═══════════════════════════════════════════════ */

.visualizer-section {
  display: flex;
  flex-direction: column;
  background: #fafafa;
}

/* Sub-header row */
.vis-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.55rem 1rem;
}

/* "PHASE 1 / STANDBY" badge */
.vis-badge {
  font-family: 'Courier New', monospace;
  font-size: 0.52rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: #aaa;
  border: 1px solid #ccc;
  padding: 0.15rem 0.45rem;
}

/* ── 2×2 stat grid ── */
.vis-stats-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  background: #e8e8e8; /* gap color between cells */
  gap: 1px;
  border-bottom: 1px solid #1a1a1a;
}

.vis-stat {
  padding: 0.75rem 1rem;
  background: #fff;
}

.vis-stat-label {
  font-family: 'Courier New', monospace;
  font-size: 0.5rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: #999;
  margin-bottom: 0.35rem;
}

.vis-stat-value {
  font-family: 'Courier New', monospace;
  font-size: 1.25rem;
  font-weight: 700;
  color: #1a1a1a;
  letter-spacing: 0.04em;
}


/* ═══════════════════════════════════════════════
   10. VISUALIZER SECTION — EVENT LOG
   ═══════════════════════════════════════════════ */

/* Log sub-header */
.vis-log-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.45rem 1rem;
  border-bottom: 1px solid #1a1a1a;
}

/* Scrollable log area */
.vis-log {
  flex: 1;
  overflow-y: auto;
  /* Limit height so the panel doesn't grow unbounded */
  max-height: 360px;
  padding: 0.25rem 0;
}

/* Individual log entry: two-column (timestamp | message) */
.log-entry {
  display: grid;
  grid-template-columns: 3.5rem 1fr;
  gap: 0.5rem;
  padding: 0.28rem 1rem;
  border-bottom: 1px solid #f0f0f0;
  line-height: 1.5;
}

.log-entry:last-child { border-bottom: none; }

.log-timestamp {
  font-family: 'Courier New', monospace;
  font-size: 0.6rem;
  color: #bbb;
  white-space: nowrap;
  letter-spacing: 0.05em;
  padding-top: 0.05rem;
}

.log-message {
  font-family: 'Courier New', monospace;
  font-size: 0.62rem;
  letter-spacing: 0.04em;
  color: #444;
}

/* Color variants per event type */
.log-entry--player   .log-message { color: #1a1a1a; font-weight: 700; }
.log-entry--ai       .log-message { color: #b91c1c; font-weight: 700; }
/* PHASE 2: change to #ff0000 when re-enabling chemical pour */
.log-entry--system   .log-message { color: #888;    font-style: italic; }
/* AI diagnostic readout lines — non-italic, slightly indented feel */
.log-entry--analysis .log-message { color: #555; letter-spacing: 0.06em; }
.log-entry--win    .log-message {
  color: #1a1a1a;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}


/* ═══════════════════════════════════════════════
   11. FOOTER
   ═══════════════════════════════════════════════ */

/* ═══════════════════════════════════════════════
   12. VISUALIZER — DIFFICULTY CONTROLS
   ═══════════════════════════════════════════════ */

/* Row: DIFFICULTY label + EASY / HARD / ADVANCED buttons */
.vis-difficulty {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.45rem 1rem;
}

.vis-difficulty-btns {
  display: flex;
  gap: 0.4rem;
  align-items: center;
}

/* The ADVANCED toggle is visually separated from the preset buttons
   by a left margin and rendered smaller + in a muted color to signal
   it's a different kind of control, not a difficulty level. */
.vis-advanced-toggle {
  margin-left: 0.6rem;
  font-size: 0.52rem;
  color: #999;
  border-color: #bbb;
  padding: 0.2rem 0.45rem;
  letter-spacing: 0.1em;
}

.vis-advanced-toggle:hover {
  background: #555;
  border-color: #555;
  color: #fff;
}

/* Advanced depth-slider row — hidden by default, shown via .open class */
.vis-difficulty-advanced {
  display: none;
  align-items: center;
  gap: 0.75rem;
  padding: 0.45rem 1rem;
  border-top: 1px solid #e8e8e8;
  background: #fafafa;
}

.vis-difficulty-advanced.open {
  display: flex;
}

/* Depth slider: monochrome, no browser chrome */
#depth-slider {
  flex: 1;
  accent-color: #1a1a1a;
  cursor: pointer;
  height: 2px;
}

.lab-footer {
  padding: 0.45rem 1rem;
  text-align: center;
}


/* ═══════════════════════════════════════════════
   13. PHASE 5 — DECISION TREE CANVAS
   Full-width strip below the main two-column area.
   ═══════════════════════════════════════════════ */

.vis-tree-container {
  background: transparent;
}

/* Header row mirrors the visualizer sub-header pattern */
.vis-tree-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.45rem 1rem;
  border-bottom: 1px solid #e8e8e8;
}

/* Canvas fills the full panel width; height is set by JS (currently 400px).
   Background is transparent so the site's CSS grid pattern shows through. */
#ai-tree-canvas {
  display: block;
  width: 100%;
  background: transparent;
}


/* ═══════════════════════════════════════════════
   14. HELP OVERLAY
   Fixed over the full viewport. Clicking the
   backdrop or the GOT IT button dismisses it.
   ═══════════════════════════════════════════════ */

.lab-overlay {
  position: fixed;
  inset: 0;
  background: rgba(26, 26, 26, 0.55);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 100;
  padding: 2rem 1rem;
  cursor: pointer; /* clicking backdrop closes */
}

.lab-overlay.hidden {
  display: none;
}

/* Inner panel: override default no-padding; cap width for readability */
.lab-overlay .lab-panel {
  max-width: 500px;
  padding: 1.75rem 2rem 1.5rem;
  cursor: default;
}

.lab-help-body {
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
  margin-top: 1rem;
  font-family: 'Courier New', monospace;
  font-size: 0.68rem;
  letter-spacing: 0.04em;
  line-height: 1.65;
  color: #444;
}

.lab-help-metrics {
  border: 1px solid #e8e8e8;
  padding: 0.85rem 1rem;
  display: flex;
  flex-direction: column;
  gap: 0.65rem;
  background: #fafafa;
}

.lab-help-metric-title {
  font-size: 0.52rem;
  letter-spacing: 0.2em;
  color: #999;
  margin-bottom: 0.1rem;
}

.lab-help-metric-row {
  display: grid;
  grid-template-columns: 3.5rem 1fr;
  gap: 0.6rem;
  align-items: start;
  font-size: 0.63rem;
  line-height: 1.5;
}

.lab-help-metric-icon {
  font-family: 'Courier New', monospace;
  font-size: 0.63rem;
  font-weight: 700;
  color: #1a1a1a;
  padding-top: 0.05rem;
}

.lab-help-tip {
  font-size: 0.6rem;
  color: #999;
  font-style: italic;
}

.lab-actions {
  display: flex;
  justify-content: flex-end;
}

.lab-action-btn {
  font-family: 'Courier New', monospace;
  font-size: 0.62rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: #fff;
  background: #1a1a1a;
  border: 1px solid #1a1a1a;
  padding: 0.5rem 1.75rem;
  cursor: pointer;
  transition: background 140ms ease;
}

.lab-action-btn:hover {
  background: #333;
}