/* ═══════════════════════════════════════════════════════
   Animations, Transitions & Loading States
   ═══════════════════════════════════════════════════════ */

/* ─── Keyframes ─────────────────────────────────────── */
@keyframes spinnerRotate { to { transform: rotate(360deg); } }
@keyframes shimmer {
  0%   { background-position: -200% 0; }
  100% { background-position: 200% 0; }
}
@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(8px); }
  to   { opacity: 1; transform: translateY(0); }
}
@keyframes fadeInScale {
  from { opacity: 0; transform: scale(0.95); }
  to   { opacity: 1; transform: scale(1); }
}
@keyframes glowPulse {
  0%, 100% { box-shadow: 0 0 8px var(--glow); }
  50%      { box-shadow: 0 0 20px var(--glow-strong); }
}

/* ─── Loading Spinner ───────────────────────────────── */
.loading-spinner {
  display: inline-block;
  width: 14px; height: 14px;
  border: 2px solid var(--border2);
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spinnerRotate 0.7s linear infinite;
  flex-shrink: 0;
}
.loading-shimmer {
  background: linear-gradient(90deg, var(--surface2) 25%, var(--surface3) 50%, var(--surface2) 75%);
  background-size: 200% 100%;
  animation: shimmer 1.5s ease infinite;
}
.btn.loading { pointer-events: none; opacity: 0.6; }
.btn.loading::after {
  content: '';
  display: inline-block;
  width: 10px; height: 10px;
  margin-left: 6px;
  border: 1.5px solid currentColor;
  border-top-color: transparent;
  border-radius: 50%;
  animation: spinnerRotate 0.6s linear infinite;
}

/* ─── Panel Transitions ─────────────────────────────── */
.sidebar { transition: width var(--duration-lg) var(--ease-out); }
.editor-panel { transition: width var(--duration-lg) var(--ease-out); }
.section-body {
  transition: max-height 0.3s var(--ease-out), opacity 0.2s ease;
  overflow: hidden;
}
.section.collapsed .section-body { max-height: 0 !important; opacity: 0; }

/* ─── Keyboard Shortcut Overlay ─────────────────────── */
#shortcutOverlay {
  display: none;
  position: fixed; inset: 0;
  z-index: 500;
  background: rgba(4,8,14,0.92);
  backdrop-filter: blur(16px);
  align-items: center;
  justify-content: center;
}
#shortcutOverlay.visible { display: flex; }
.shortcut-dialog {
  background: var(--surface);
  border: 1px solid var(--border2);
  border-radius: var(--radius-xl);
  padding: 28px 36px;
  max-width: 540px;
  width: 90vw;
  box-shadow: var(--shadow-lg);
  animation: fadeInScale 0.25s var(--ease-out);
}
.shortcut-dialog h2 {
  font-family: 'Playfair Display', serif;
  font-size: 19px;
  color: var(--accent);
  margin-bottom: 18px;
  display: flex;
  align-items: center;
  gap: 10px;
}
.shortcut-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 6px 28px;
}
.shortcut-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 6px 0;
  font-size: 12px;
  color: var(--text-dim);
}
.shortcut-row kbd {
  background: var(--bg);
  border: 1px solid var(--border2);
  padding: 3px 10px;
  border-radius: 5px;
  font-family: 'JetBrains Mono', monospace;
  font-size: 10px;
  color: var(--accent);
  min-width: 42px;
  text-align: center;
}

/* ─── Canvas Loading Overlay ────────────────────────── */
#canvasLoading {
  position: absolute; inset: 0;
  display: none;
  background: rgba(6,10,16,0.7);
  backdrop-filter: blur(6px);
  align-items: center;
  justify-content: center;
  flex-direction: column;
  gap: 14px;
  z-index: 15;
  font-family: 'JetBrains Mono', monospace;
  font-size: 11px;
  color: var(--text-dim);
}
#canvasLoading.visible { display: flex; }
#canvasLoading .loading-spinner {
  width: 32px; height: 32px;
  border-width: 3px;
}

/* ─── Draw Modal Responsive ─────────────────────────── */
@media (max-width: 1180px) {
  .dm-left { width: 220px; min-width: 220px; max-width: 280px; }
  .dm-left.expanded { width: 300px; min-width: 300px; max-width: 320px; }
  .dm-right { width: 200px; min-width: 200px; max-width: 240px; }
  .dm-header { gap: 10px; }
}
@media (max-width: 980px) {
  .dm-dialog { width: min(98vw, 1340px); height: min(96vh, 860px); }
  .dm-header { flex-wrap: wrap; height: auto; padding: 10px 14px; }
  .dm-header-pills { order: 3; width: 100%; }
  .dm-body { flex-direction: column; }
  .dm-left, .dm-left.expanded, .dm-left.compact, .dm-left.collapsed, .dm-right {
    width: 100%; max-width: none; min-width: 0;
    border-right: none; border-left: none; opacity: 1;
  }
  .dm-left { max-height: 46vh; border-bottom: 1px solid var(--border); }
  .dm-left.collapsed { max-height: 0; border-right: none; border-bottom: none; }
  .dm-right { max-height: 32vh; border-top: 1px solid var(--border); }
  .dm-template-grid { max-height: min(28vh, 320px); }
}

/* ─── Responsive: Tablet ────────────────────────────── */
@media (max-width: 768px) {
  .sidebar { width: 220px; }
  .toolbar { gap: 2px; padding: 4px; }
  .toolbar .btn { padding: 3px 6px; font-size: 9px; }
  .shortcut-grid { grid-template-columns: 1fr; }
}

/* ─── Responsive: Phone ─────────────────────────────── */
@media (max-width: 480px) {
  .sidebar { width: 100vw; position: absolute; z-index: 50; top: 0; bottom: 0; }
  .sidebar.collapsed { width: 0; }
  header { padding: 0 10px; gap: 8px; }
  .logo { font-size: 14px; }
  .logo sub { display: none; }
  .toolbar { bottom: 8px; padding: 3px; border-radius: 8px; }
}