.app-header {
  display: flex;
  align-items: center;
  gap: var(--spacing-3);
  height: var(--header-height);
  padding: 0 var(--spacing-4);
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
  box-shadow: var(--shadow-xs);
  position: sticky;
  top: 0;
  z-index: 100;
  flex-shrink: 0;
}

.app-header__brand {
  display: flex;
  align-items: center;
  gap: var(--spacing-2);
  flex-shrink: 0;
}

.app-header__logo {
  display: flex;
  align-items: center;
}

.app-header__app-name {
  font-size: var(--font-size-md);
  font-weight: var(--font-weight-bold);
  color: var(--color-text-primary);
  letter-spacing: -0.3px;
}

.app-header__badge {
  font-size: var(--font-size-xs);
  font-weight: var(--font-weight-semibold);
  color: var(--color-primary);
  background: var(--color-primary-light);
  padding: 1px 6px;
  border-radius: var(--radius-full);
}

.app-header__form-title-wrap {
  display: flex;
  align-items: center;
  gap: var(--spacing-3);
  flex: 1;
  min-width: 0;
}

.app-header__form-title {
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-semibold);
  color: var(--color-text-primary);
  border: 1px solid transparent;
  border-radius: var(--radius-md);
  padding: 4px 8px;
  width: 100%;
  max-width: 320px;
  background: transparent;
  transition:
    border-color var(--transition-fast),
    background var(--transition-fast);
}

.app-header__form-title:hover {
  border-color: var(--color-border);
  background: var(--color-background);
}

.app-header__form-title:focus {
  border-color: var(--color-border-focus);
  background: var(--color-surface);
  box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.15);
}

.app-header__autosave {
  display: flex;
  align-items: center;
  gap: 5px;
  font-size: var(--font-size-xs);
  color: var(--color-text-tertiary);
  flex-shrink: 0;
}

.autosave-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--color-success);
  transition: background var(--transition-base);
}

.autosave-dot--dirty {
  background: var(--color-warning);
}
.autosave-dot--saving {
  background: var(--color-primary);
  animation: pulse 1s ease infinite;
}

@keyframes pulse {
  0%,
  100% {
    opacity: 1;
  }
  50% {
    opacity: 0.4;
  }
}

.app-header__actions {
  display: flex;
  align-items: center;
  gap: var(--spacing-1);
  flex-shrink: 0;
}

.app-header__changes-wrap {
  position: relative;
}

.changes-badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 18px;
  height: 18px;
  padding: 0 4px;
  background: var(--color-warning);
  color: white;
  border-radius: var(--radius-full);
  font-size: var(--font-size-xs);
  font-weight: var(--font-weight-bold);
}

.app-workspace {
  display: flex;
  height: calc(100vh - var(--header-height) - var(--statusbar-height));
  overflow: hidden;
}

.panel {
  display: flex;
  flex-direction: column;
  background: var(--color-surface);
  overflow: hidden;
  transition: width var(--transition-slow);
  flex-shrink: 0;
}

.panel--palette {
  width: var(--palette-width);
  min-width: 180px;
  border-right: 1px solid var(--color-border);
}

.panel--palette.collapsed {
  width: 0;
  min-width: 0;
  border-right: none;
  overflow: hidden;
}

.panel--canvas {
  flex: 1;
  background: var(--color-background);
  min-width: 0;
}

.panel--properties {
  width: var(--properties-width);
  min-width: 220px;
  border-left: 1px solid var(--color-border);
}

.panel--properties.collapsed {
  width: 0;
  min-width: 0;
  border-left: none;
  overflow: hidden;
}

.panel__header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--spacing-3) var(--spacing-4);
  border-bottom: 1px solid var(--color-border);
  flex-shrink: 0;
  background: var(--color-surface);
}

.panel__title {
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-semibold);
  color: var(--color-text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.panel__collapse-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 24px;
  height: 24px;
  border-radius: var(--radius-sm);
  color: var(--color-text-tertiary);
  transition:
    color var(--transition-fast),
    background var(--transition-fast);
}

.panel__collapse-btn:hover {
  color: var(--color-text-primary);
  background: var(--color-background);
}

.panel-gutter {
  width: 4px;
  background: var(--color-border);
  cursor: col-resize;
  flex-shrink: 0;
  transition: background var(--transition-fast);
  position: relative;
}

.panel-gutter:hover {
  background: var(--color-primary);
}
.panel-gutter.dragging {
  background: var(--color-primary);
}

.panel-gutter::after {
  content: "";
  position: absolute;
  inset: 0 -4px;
}

.canvas-toolbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--spacing-2) var(--spacing-4);
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
  flex-shrink: 0;
  gap: var(--spacing-2);
}

.canvas-toolbar__left,
.canvas-toolbar__center,
.canvas-toolbar__right {
  display: flex;
  align-items: center;
  gap: var(--spacing-2);
}

.canvas-toolbar__zoom-label {
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-medium);
  color: var(--color-text-secondary);
  min-width: 36px;
  text-align: center;
}

.canvas-toolbar__page-label {
  font-size: var(--font-size-sm);
  color: var(--color-text-secondary);
}

.canvas-scroll-container {
  flex: 1;
  overflow: auto;
  padding: var(--spacing-6);
  display: flex;
  justify-content: center;
  align-items: flex-start;
}

.canvas {
  width: 100%;
  max-width: 800px;
  min-height: 500px;
  background: var(--color-surface);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-md);
  padding: var(--spacing-6);
  position: relative;
  transition: transform var(--transition-base);
  transform-origin: top center;
  flex-shrink: 0;
}

.canvas.drag-over {
  outline: 2px dashed var(--color-primary);
  outline-offset: -2px;
}

.app-statusbar {
  display: flex;
  align-items: center;
  height: var(--statusbar-height);
  padding: 0 var(--spacing-4);
  background: var(--color-surface);
  border-top: 1px solid var(--color-border);
  gap: 0;
  flex-shrink: 0;
}

.app-statusbar__item {
  font-size: var(--font-size-xs);
  color: var(--color-text-tertiary);
  padding: 0 var(--spacing-3);
  white-space: nowrap;
}

.app-statusbar__sep {
  width: 1px;
  height: 14px;
  background: var(--color-border);
}

.app-statusbar__spacer {
  flex: 1;
}

.modal-overlay {
  display: none;
  position: fixed;
  inset: 0;
  background: var(--color-overlay);
  z-index: 200;
  backdrop-filter: blur(2px);
  -webkit-backdrop-filter: blur(2px);
}

.modal-overlay.visible {
  display: block;
}

.modal {
  position: fixed;
  inset: 0;
  z-index: 201;
  display: flex;
  align-items: center;
  justify-content: center;
  pointer-events: none;
}

.modal[hidden] {
  display: none;
}

.modal:not([hidden]) {
  pointer-events: auto;
  animation: modal-in var(--transition-slow) cubic-bezier(0.34, 1.56, 0.64, 1)
    forwards;
}

@keyframes modal-in {
  from {
    opacity: 0;
    transform: scale(0.92);
  }
  to {
    opacity: 1;
    transform: scale(1);
  }
}

.modal__panel {
  background: var(--color-surface);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-xl);
  width: 520px;
  max-width: calc(100vw - 40px);
  max-height: calc(100vh - 80px);
  overflow: hidden;
  display: flex;
  flex-direction: column;
}

.modal__panel--sm {
  width: 380px;
}
.modal__panel--lg {
  width: 760px;
}

.modal--fullscreen .modal__panel--fullscreen {
  width: 100%;
  max-width: 100%;
  height: 100%;
  max-height: 100%;
  border-radius: 0;
}

.modal__header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--spacing-4) var(--spacing-6);
  border-bottom: 1px solid var(--color-border);
  flex-shrink: 0;
}

.modal__header--preview {
  background: var(--color-text-primary);
  color: white;
  padding: var(--spacing-3) var(--spacing-4);
}

.modal__title {
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-semibold);
}

.modal__header--preview .modal__title {
  color: white;
  font-size: var(--font-size-base);
}

.modal__close {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  border-radius: var(--radius-md);
  color: var(--color-text-secondary);
  transition:
    background var(--transition-fast),
    color var(--transition-fast);
  flex-shrink: 0;
}

.modal__close:hover {
  background: var(--color-background);
  color: var(--color-text-primary);
}
.modal__header--preview .modal__close {
  color: rgba(255, 255, 255, 0.7);
}
.modal__header--preview .modal__close:hover {
  background: rgba(255, 255, 255, 0.1);
  color: white;
}

.modal__body {
  flex: 1;
  overflow-y: auto;
  padding: var(--spacing-6);
}

.modal__body--preview {
  padding: 0;
  background: #1e1e2e;
  display: flex;
  justify-content: center;
  align-items: flex-start;
}

.modal__footer {
  display: flex;
  justify-content: flex-end;
  gap: var(--spacing-2);
  margin-top: var(--spacing-4);
  padding-top: var(--spacing-4);
  border-top: 1px solid var(--color-border);
}