/* =============================================================
   playground.css — Playground Lab: live CSS editor with split pane
   A Love Letter to the Web
   ============================================================= */

/* ── Page Shell ─────────────────────────────────────────────── */
.playground-page {
  display: flex;
  flex-direction: column;
  min-height: 100dvh;
  padding-top: 5rem; /* offset for fixed header */
  gap: 0;
}

/* ── Lab Header ─────────────────────────────────────────────── */
.lab-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-lg) var(--content-padding);
  border-bottom: 1px solid var(--color-border);
  gap: var(--space-lg);
}

.lab-header__left {
  display: flex;
  align-items: center;
  gap: var(--space-md);
}

.lab-badge {
  font-size: 1.5rem;
  color: var(--color-primary);
  filter: drop-shadow(0 0 8px oklch(60% 0.18 265 / 0.5));
  animation: glow 3s ease-in-out infinite;
  flex-shrink: 0;
  line-height: 1;
}

.lab-title {
  font-size: var(--text-xl);
  font-weight: 700;
  letter-spacing: -0.03em;
  color: var(--color-text);
  line-height: 1.2;
}

.lab-subtitle {
  font-size: var(--text-sm);
  color: var(--color-muted);
  margin-top: 0.15rem;
  line-height: 1.4;
}

.lab-header__right {
  flex-shrink: 0;
}

.lab-status {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: var(--color-muted);
  padding: var(--space-xs) var(--space-md);
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-pill);
  transition: color var(--duration-base) var(--ease-out);
}

.status-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: oklch(68% 0.2 145);
  box-shadow: 0 0 6px oklch(68% 0.2 145 / 0.6);
  animation: pulse 2s ease-in-out infinite;
  flex-shrink: 0;
}

.lab-status.updating .status-dot {
  background: oklch(72% 0.2 60);
  box-shadow: 0 0 6px oklch(72% 0.2 60 / 0.6);
}

.lab-status.updating {
  color: oklch(72% 0.2 60);
}

/* ── Toolbar ────────────────────────────────────────────────── */
.toolbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: var(--space-md);
  padding: var(--space-md) var(--content-padding);
  background: oklch(10% 0.012 265);
  border-bottom: 1px solid var(--color-border);
}

.toolbar__presets {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  flex-wrap: wrap;
}

.toolbar__label {
  font-size: var(--text-xs);
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-muted);
  margin-right: var(--space-xs);
  white-space: nowrap;
}

.preset-pill {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  font-weight: 600;
  color: var(--color-muted);
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-pill);
  padding: 0.3rem 0.75rem;
  cursor: pointer;
  transition:
    color       var(--duration-fast) var(--ease-out),
    background  var(--duration-fast) var(--ease-out),
    border-color var(--duration-fast) var(--ease-out),
    transform   var(--duration-fast) var(--ease-out),
    box-shadow  var(--duration-fast) var(--ease-out);
  white-space: nowrap;
}

.preset-pill:hover {
  color: var(--color-text);
  background: oklch(16% 0.02 265);
  border-color: oklch(35% 0.05 265);
}

.preset-pill:active {
  transform: scale(0.96);
}

.preset-pill[aria-pressed="true"],
.preset-pill.active {
  color: var(--color-primary);
  background: oklch(60% 0.18 265 / 0.12);
  border-color: oklch(60% 0.18 265 / 0.5);
  box-shadow: 0 0 12px oklch(60% 0.18 265 / 0.15);
}

.toolbar__actions {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  flex-shrink: 0;
}

.action-btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-xs);
  font-size: var(--text-sm);
  font-weight: 600;
  padding: 0.35rem 0.875rem;
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
  cursor: pointer;
  transition:
    color        var(--duration-fast) var(--ease-out),
    background   var(--duration-fast) var(--ease-out),
    border-color var(--duration-fast) var(--ease-out),
    transform    var(--duration-fast) var(--ease-out);
}

.action-btn:active {
  transform: scale(0.96);
}

.action-btn--share {
  color: var(--color-text);
  background: var(--color-surface);
}

.action-btn--share:hover {
  color: var(--color-primary);
  border-color: oklch(60% 0.18 265 / 0.5);
  background: oklch(60% 0.18 265 / 0.1);
}

.action-btn--clear {
  color: var(--color-muted);
  background: transparent;
}

.action-btn--clear:hover {
  color: oklch(68% 0.2 15);
  border-color: oklch(68% 0.2 15 / 0.4);
  background: oklch(68% 0.2 15 / 0.08);
}

/* ── Split Pane ─────────────────────────────────────────────── */
.editor-split {
  display: grid;
  grid-template-columns: 1fr 1fr;
  flex: 1;
  min-height: 0;
  overflow: hidden;
}

/* ── Shared Pane Styles ─────────────────────────────────────── */
.editor-pane,
.preview-pane {
  display: flex;
  flex-direction: column;
  min-height: calc(100dvh - 5rem - 4.5rem - 3.5rem); /* subtract header, labheader, toolbar */
  overflow: hidden;
}

.editor-pane {
  border-right: 1px solid var(--color-border);
  background: oklch(7% 0.01 265);
}

.preview-pane {
  background: oklch(10% 0.012 265);
}

/* ── Pane Header ────────────────────────────────────────────── */
.pane-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-sm) var(--space-md);
  background: oklch(10% 0.012 265);
  border-bottom: 1px solid var(--color-border);
  flex-shrink: 0;
}

.editor-pane .pane-header {
  background: oklch(9% 0.01 265);
}

.pane-header__left {
  display: flex;
  align-items: center;
  gap: var(--space-md);
}

.pane-header__right {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

/* macOS-style traffic lights */
.traffic-light {
  display: flex;
  align-items: center;
  gap: 5px;
}

.traffic-light span {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--color-border);
  opacity: 0.6;
}

.traffic-light span:nth-child(1) { background: oklch(65% 0.2 25); }
.traffic-light span:nth-child(2) { background: oklch(72% 0.2 75); }
.traffic-light span:nth-child(3) { background: oklch(65% 0.2 150); }

.pane-header__title {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: var(--color-muted);
  letter-spacing: 0.02em;
}

.pane-header__lang {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  font-weight: 600;
  color: var(--color-primary);
  background: oklch(60% 0.18 265 / 0.12);
  padding: 0.15rem 0.5rem;
  border-radius: var(--radius-sm);
  letter-spacing: 0.05em;
}

.pane-icon-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  color: var(--color-muted);
  border-radius: var(--radius-sm);
  transition:
    color      var(--duration-fast) var(--ease-out),
    background var(--duration-fast) var(--ease-out);
}

.pane-icon-btn:hover {
  color: var(--color-text);
  background: var(--color-border);
}

/* ── Editor ─────────────────────────────────────────────────── */
.editor-wrapper {
  display: flex;
  flex: 1;
  overflow: auto;
  position: relative;
  scrollbar-width: thin;
  scrollbar-color: var(--color-border) transparent;
}

.editor-wrapper::-webkit-scrollbar {
  width: 6px;
  height: 6px;
}

.editor-wrapper::-webkit-scrollbar-track {
  background: transparent;
}

.editor-wrapper::-webkit-scrollbar-thumb {
  background: var(--color-border);
  border-radius: var(--radius-pill);
}

.line-numbers {
  flex-shrink: 0;
  width: 2.75rem;
  padding: var(--space-md) 0;
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  line-height: 1.7;
  text-align: right;
  color: oklch(40% 0.02 265);
  user-select: none;
  border-right: 1px solid var(--color-border);
  background: oklch(7.5% 0.01 265);
  padding-right: var(--space-sm);
}

.line-numbers span {
  display: block;
}

.editor-content {
  flex: 1;
  padding: var(--space-md);
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  line-height: 1.7;
  color: oklch(82% 0.02 265);
  white-space: pre-wrap;
  word-break: break-all;
  outline: none;
  min-height: 100%;
  caret-color: var(--color-primary);
  tab-size: 2;
}

.editor-content:focus-visible {
  box-shadow: inset 0 0 0 2px var(--color-primary);
}

.editor-content:empty::before {
  content: "/* start typing your CSS here… */";
  color: oklch(35% 0.02 265);
  font-style: italic;
  pointer-events: none;
}

/* ── Preview Iframe ─────────────────────────────────────────── */
.preview-wrapper {
  flex: 1;
  position: relative;
  overflow: hidden;
}

#preview-frame {
  width: 100%;
  height: 100%;
  border: none;
  display: block;
}

/* ── Toast Notification ─────────────────────────────────────── */
.toast {
  position: fixed;
  bottom: var(--space-xl);
  left: 50%;
  transform: translateX(-50%) translateY(calc(100% + var(--space-xl)));
  z-index: var(--z-toast);
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  padding: var(--space-sm) var(--space-lg);
  background: oklch(88% 0.01 265);
  color: oklch(8% 0.01 265);
  font-size: var(--text-sm);
  font-weight: 600;
  border-radius: var(--radius-pill);
  box-shadow:
    0 8px 32px oklch(0% 0 0 / 0.4),
    0 2px 8px  oklch(0% 0 0 / 0.2);
  transition: transform var(--duration-slow) var(--ease-out);
  pointer-events: none;
}

.toast.visible {
  transform: translateX(-50%) translateY(0);
}

.toast__icon {
  color: oklch(55% 0.2 145);
  font-weight: 700;
}

.toast__message {
  white-space: nowrap;
}

/* ── Responsive: Mobile Stack ───────────────────────────────── */
@media (max-width: 768px) {
  .editor-split {
    grid-template-columns: 1fr;
    grid-template-rows: auto auto;
    overflow: visible;
  }

  .editor-pane,
  .preview-pane {
    min-height: 50dvh;
    border-right: none;
  }

  .editor-pane {
    border-bottom: 1px solid var(--color-border);
  }

  .lab-header {
    flex-direction: column;
    align-items: flex-start;
    gap: var(--space-sm);
    padding: var(--space-md) var(--content-padding);
  }

  .lab-header__right {
    align-self: flex-end;
  }

  .toolbar {
    gap: var(--space-sm);
  }

  .toolbar__presets {
    gap: 0.375rem;
  }

  .line-numbers {
    display: none;
  }

  .toast {
    bottom: var(--space-md);
    left: var(--content-padding);
    right: var(--content-padding);
    transform: translateX(0) translateY(calc(100% + var(--space-md)));
  }

  .toast.visible {
    transform: translateX(0) translateY(0);
  }
}

/* ── Tablet Tweaks ──────────────────────────────────────────── */
@media (min-width: 769px) and (max-width: 1024px) {
  .editor-split {
    grid-template-columns: 45% 55%;
  }

  .toolbar__label {
    display: none;
  }
}

/* ── Ambient Grid (Layer 1 / Task 5) ─────────────────── */
.ambient-bg--grid {
  background-image: linear-gradient(oklch(1 0 0 / 0.05) 1px, transparent 1px),
                    linear-gradient(90deg, oklch(1 0 0 / 0.05) 1px, transparent 1px);
  background-size: 40px 40px;
  animation: ambient-pulse 10s ease-in-out infinite;
}

/* ── Editor Status Bar (Layer 1 / Task 26) ───────────── */
.editor-status-bar {
  display: flex; gap: 12px; padding: 6px 10px; background: oklch(0.15 0.02 280);
  border-top: 1px solid oklch(1 0 0 / 0.1);
  font-family: "JetBrains Mono", monospace; font-size: 0.75rem;
  align-items: center;
}
.editor-status-bar button { margin-left: auto; padding: 2px 10px; font-size: 0.75rem; background: transparent; color: inherit; border: 1px solid oklch(1 0 0 / 0.15); border-radius: 4px; cursor: pointer; }
.editor-status-bar button:hover { background: oklch(0.22 0.03 280); }