/**
 * lab.css — Lab page (Layer 2 / Task 5)
 * Advanced CSS shape builder: split-pane controls + live preview + dialogs.
 */

.lab {
  padding: var(--space-2xl) var(--space-lg);
  max-width: 1400px;
  margin: 0 auto;
}

.lab-header {
  text-align: center;
  margin-bottom: var(--space-lg);
}

.lab-header h1 {
  font-size: clamp(2rem, 5vw, 3.5rem);
  margin-bottom: var(--space-sm);
}

.lab-header p {
  color: oklch(0.7 0.04 280);
  font-size: 1.05rem;
}

.lab-pane {
  display: grid;
  grid-template-columns: 360px 1fr;
  gap: var(--space-lg);
  margin-top: var(--space-lg);
  align-items: start;
}

@media (max-width: 900px) {
  .lab-pane {
    grid-template-columns: 1fr;
  }
  .lab-controls {
    position: static !important;
    max-height: none !important;
  }
}

.lab-controls {
  background: oklch(0.18 0.02 280 / 0.7);
  border: 1px solid oklch(1 0 0 / 0.08);
  border-radius: 12px;
  padding: 16px;
  max-height: 80vh;
  overflow-y: auto;
  position: sticky;
  top: 100px;
}

.lab-toolbar-top {
  display: flex;
  gap: 8px;
  margin-bottom: 12px;
}

.lab-toolbar-top button,
.lab-toolbar-bottom button {
  flex: 1;
  padding: 8px 12px;
  border-radius: 8px;
  background: oklch(0.22 0.04 280);
  color: white;
  border: 1px solid oklch(1 0 0 / 0.1);
  cursor: pointer;
  font: inherit;
  font-size: 0.85rem;
  transition: background 180ms ease, transform 180ms ease;
}

.lab-toolbar-top button:hover,
.lab-toolbar-bottom button:hover {
  background: oklch(0.28 0.06 280);
}

.lab-toolbar-top button:active,
.lab-toolbar-bottom button:active {
  transform: translateY(1px);
}

.lab-section {
  margin: 8px 0;
  padding: 10px;
  background: oklch(1 0 0 / 0.03);
  border-radius: 8px;
}

.lab-section[open] {
  background: oklch(1 0 0 / 0.05);
}

.lab-section summary {
  font-weight: 600;
  cursor: pointer;
  padding: 4px 0;
  user-select: none;
  list-style: revert;
}

.lab-section label {
  display: grid;
  grid-template-columns: 90px 1fr auto;
  gap: 8px;
  align-items: center;
  padding: 4px 0;
  font-size: 0.85rem;
}

.lab-section input[type="range"] {
  width: 100%;
}

.lab-section input[type="color"] {
  width: 100%;
  height: 28px;
  border: none;
  cursor: pointer;
  background: transparent;
  padding: 0;
}

.lab-section select {
  padding: 4px 8px;
  background: oklch(0.2 0.02 280);
  color: white;
  border: 1px solid oklch(1 0 0 / 0.1);
  border-radius: 4px;
  font: inherit;
  font-size: 0.85rem;
}

.ctl-val {
  font-family: var(--font-code, monospace);
  font-size: 0.8rem;
  color: oklch(0.7 0.18 290);
  min-width: 40px;
  text-align: right;
}

.lab-preview-wrap {
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
}

.lab-preview {
  background-image:
    linear-gradient(45deg, oklch(0.15 0.02 280) 25%, transparent 25%),
    linear-gradient(-45deg, oklch(0.15 0.02 280) 25%, transparent 25%),
    linear-gradient(45deg, transparent 75%, oklch(0.15 0.02 280) 75%),
    linear-gradient(-45deg, transparent 75%, oklch(0.15 0.02 280) 75%);
  background-size: 20px 20px;
  background-position: 0 0, 0 10px, 10px -10px, 10px 0px;
  min-height: 500px;
  border: 1px solid oklch(1 0 0 / 0.08);
  border-radius: 12px;
  display: grid;
  place-items: center;
  padding: 32px;
  overflow: hidden;
}

.lab-canvas {
  transition: all 200ms ease;
}

.lab-toolbar-bottom {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.lab-css-output {
  background: oklch(0.12 0.02 280);
  border: 1px solid oklch(1 0 0 / 0.08);
  border-radius: 8px;
  padding: 8px 12px;
}

.lab-css-output summary {
  font-weight: 600;
  cursor: pointer;
  padding: 4px 0;
  user-select: none;
}

.lab-css-output pre {
  background: oklch(0.1 0.02 280);
  color: oklch(0.7 0.18 200);
  padding: 16px;
  border-radius: 8px;
  overflow-x: auto;
  font-size: 0.85rem;
  margin: 8px 0 0 0;
  white-space: pre-wrap;
  word-break: break-word;
}

/* Dialogs */
.lab-dialog {
  padding: 24px;
  border-radius: 16px;
  background: oklch(0.18 0.02 280);
  color: white;
  border: 1px solid oklch(1 0 0 / 0.1);
  max-width: 720px;
  width: 90vw;
}

.lab-dialog::backdrop {
  background: oklch(0 0 0 / 0.7);
  backdrop-filter: blur(4px);
}

.lab-dialog__head {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 16px;
}

.lab-dialog__head h2 {
  margin: 0;
  font-size: 1.25rem;
}

.lab-dialog__head button[data-close] {
  background: transparent;
  border: none;
  color: white;
  font-size: 1.5rem;
  cursor: pointer;
  padding: 4px 12px;
  line-height: 1;
}

.lab-thumb-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
  gap: 12px;
  max-height: 60vh;
  overflow-y: auto;
}

.lab-thumb {
  aspect-ratio: 1;
  border-radius: 8px;
  cursor: pointer;
  position: relative;
  padding: 8px;
  background: oklch(1 0 0 / 0.05);
  border: 1px solid oklch(1 0 0 / 0.08);
  transition: transform 200ms ease;
  overflow: hidden;
  display: grid;
  place-items: center;
}

.lab-thumb:hover {
  transform: scale(1.05);
}

.lab-thumb:focus-visible {
  outline: 2px solid oklch(0.7 0.18 290);
  outline-offset: 2px;
}

.lab-thumb__name {
  position: absolute;
  bottom: 4px;
  left: 4px;
  right: 4px;
  font-size: 0.75rem;
  background: oklch(0 0 0 / 0.6);
  padding: 2px 6px;
  border-radius: 4px;
  text-align: center;
  pointer-events: none;
}

.lab-dialog--small {
  max-width: 400px;
}

.lab-dialog--small input {
  width: 100%;
  padding: 10px;
  border-radius: 8px;
  background: oklch(0.22 0.04 280);
  color: white;
  border: 1px solid oklch(1 0 0 / 0.1);
  margin: 12px 0;
  font: inherit;
}

.lab-dialog--small h2 {
  margin: 0;
  font-size: 1.15rem;
}

.lab-dialog__actions {
  display: flex;
  justify-content: flex-end;
  gap: 8px;
}

.lab-dialog__actions button {
  padding: 8px 16px;
  border-radius: 8px;
  background: oklch(0.22 0.04 280);
  color: white;
  border: 1px solid oklch(1 0 0 / 0.1);
  cursor: pointer;
  font: inherit;
}

.lab-dialog__actions button:hover {
  background: oklch(0.28 0.06 280);
}

/* Animation presets used by canvas */
@keyframes spin {
  to { transform: rotate(360deg); }
}

@keyframes float {
  0%, 100% { translate: 0 0; }
  50% { translate: 0 -20px; }
}

@keyframes pulse {
  0%, 100% { transform: scale(1); }
  50% { transform: scale(1.05); }
}

@keyframes wobble {
  0%, 100% { transform: rotate(0); }
  25% { transform: rotate(3deg); }
  75% { transform: rotate(-3deg); }
}

@media (prefers-reduced-motion: reduce) {
  .lab-canvas {
    animation: none !important;
  }
}