:root {
  --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
  --color-bg: #f8fafc;
  --color-sidebar: #ffffff;
  --color-card-bg: #ffffff;
  --color-border: #e2e8f0;
  --color-border-hover: #cbd5e1;
  --color-text-primary: #0f172a;
  --color-text-secondary: #475569;
  --color-text-muted: #94a3b8;
  
  --color-primary: #1e5f74;
  --color-primary-hover: #164858;
  --color-primary-light: #e6f3f7;
  
  --color-success: #15803d;
  --color-success-bg: #f0fdf4;
  --color-success-border: #bbf7d0;

  --color-danger: #b91c1c;
  --color-danger-hover: #991b1b;
  --color-danger-bg: #fef2f2;
  --color-danger-border: #fecaca;

  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -2px rgba(0, 0, 0, 0.05);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -4px rgba(0, 0, 0, 0.05);
}

/* UI Icons (Clean industrial SVG icons) */
.ui-icon {
  width: 1.15em;
  height: 1.15em;
  display: inline-block;
  vertical-align: -0.15em;
  fill: none;
  stroke: currentColor;
  stroke-width: 2;
  stroke-linecap: round;
  stroke-linejoin: round;
  flex-shrink: 0;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  padding: 0;
  background: var(--color-bg);
  color: var(--color-text-primary);
  font-family: var(--font-family);
  overflow: hidden;
  -webkit-font-smoothing: antialiased;
}

#main {
  display: flex;
  height: 100vh;
  width: 100vw;
  overflow: hidden;
}

/* -------------------------------------------------------------
 * Sidebar
 * ------------------------------------------------------------- */
#sidebar {
  width: 380px;
  min-width: 340px;
  max-width: 440px;
  background: var(--color-sidebar);
  border-right: 1px solid var(--color-border);
  padding: 20px;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  gap: 16px;
  box-shadow: 2px 0 10px rgba(0, 0, 0, 0.03);
  z-index: 10;
}

#sidebar::-webkit-scrollbar {
  width: 6px;
}
#sidebar::-webkit-scrollbar-track {
  background: transparent;
}
#sidebar::-webkit-scrollbar-thumb {
  background: #cbd5e1;
  border-radius: 4px;
}
#sidebar::-webkit-scrollbar-thumb:hover {
  background: #94a3b8;
}

/* Sidebar Header */
.sidebar-header {
  display: flex;
  flex-direction: column;
  gap: 12px;
  padding-bottom: 14px;
  border-bottom: 1px solid var(--color-border);
}

.sidebar-header-top {
  display: flex;
  align-items: center;
  justify-content: flex-start;
  width: 100%;
}

.brand {
  display: flex;
  flex-direction: column;
  gap: 3px;
}

.brand-logo {
  height: 24px;
  width: auto;
  max-width: 220px;
  object-fit: contain;
  filter: contrast(1.1);
}

.brand-tag {
  font-size: 0.65rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  color: var(--color-text-secondary);
  text-transform: uppercase;
}

/* Language Switcher */
.lang-switch {
  display: inline-flex;
  background: #f1f5f9;
  padding: 3px;
  border-radius: var(--radius-md);
  gap: 2px;
  flex-shrink: 0;
}

.lang-btn {
  border: none;
  background: transparent;
  padding: 5px 10px;
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--color-text-secondary);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all 0.15s ease-in-out;
}

.lang-btn.active {
  background: #ffffff;
  color: var(--color-primary);
  box-shadow: var(--shadow-sm);
}

/* -------------------------------------------------------------
 * Cards & Layout
 * ------------------------------------------------------------- */
.card {
  background: var(--color-card-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 14px;
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
  gap: 12px;
  transition: border-color 0.15s ease;
}

.card:hover {
  border-color: var(--color-border-hover);
}

.global-params-card {
  background: #f8fafc;
}

/* -------------------------------------------------------------
 * Collapsible Unit Cards & Toolbar
 * ------------------------------------------------------------- */
.unit-toolbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 4px 2px;
  margin-top: 4px;
  margin-bottom: 2px;
}

.unit-toolbar-title {
  font-size: 0.8rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--color-text-secondary);
}

.unit-toolbar-actions {
  display: flex;
  gap: 8px;
}

.unit-toolbar-btn {
  background: none;
  border: none;
  padding: 2px 6px;
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--color-primary);
  cursor: pointer;
  border-radius: var(--radius-sm);
  transition: all 0.15s ease;
}

.unit-toolbar-btn:hover {
  background: var(--color-primary-light);
  color: var(--color-primary-hover);
}

.unit-card {
  border-left: 4px solid var(--color-primary);
  transition: border-color 0.15s ease;
}

.corner-unit-card {
  border-left: 4px solid #0f766e;
}

.flex-1 {
  flex: 1;
}

.unit-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 8px;
}

.unit-header-toggle {
  display: flex;
  align-items: center;
  gap: 8px;
  background: none;
  border: none;
  padding: 3px 6px;
  margin: -3px -6px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  text-align: left;
  font-family: inherit;
  color: inherit;
  transition: background-color 0.15s ease;
}

.unit-header-toggle:hover {
  background: #f1f5f9;
}

.unit-header-toggle:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 1px;
}

.unit-toggle-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  color: var(--color-text-secondary);
  transition: transform 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  flex-shrink: 0;
}

.unit-card.is-collapsed .unit-toggle-icon {
  transform: rotate(-90deg);
}

.unit-card:not(.is-collapsed) .unit-toggle-icon {
  transform: rotate(0deg);
}

.unit-header-actions {
  display: flex;
  align-items: center;
  gap: 6px;
}

.unit-title {
  margin: 0;
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--color-text-primary);
}

.unit-primary-controls {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.unit-summary-chips {
  display: none;
  flex-wrap: wrap;
  gap: 6px;
  margin-top: 2px;
}

.unit-card.is-collapsed .unit-summary-chips {
  display: flex;
}

.unit-chip {
  font-size: 0.72rem;
  font-weight: 600;
  padding: 2px 7px;
  background: #f1f5f9;
  border: 1px solid #e2e8f0;
  border-radius: 12px;
  color: var(--color-text-secondary);
  white-space: nowrap;
}

.unit-chip-accent {
  background: var(--color-primary-light);
  border-color: #bee1eb;
  color: var(--color-primary);
}

.unit-details-body {
  display: flex;
  flex-direction: column;
  gap: 12px;
  padding-top: 4px;
  border-top: 1px dashed var(--color-border);
}

.unit-card.is-collapsed .unit-details-body {
  display: none;
}


.mono-num {
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
  font-variant-numeric: tabular-nums;
}

/* -------------------------------------------------------------
 * Forms & Inputs
 * ------------------------------------------------------------- */
.form-row {
  display: flex;
  flex-direction: column;
  gap: 5px;
}

.form-grid-2 {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
}

.form-col {
  display: flex;
  flex-direction: column;
  gap: 5px;
}

.form-label {
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--color-text-secondary);
}

.input-control, .select-control {
  width: 100%;
  padding: 8px 10px;
  font-size: 0.88rem;
  font-family: inherit;
  color: var(--color-text-primary);
  background: #ffffff;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  transition: all 0.15s ease-in-out;
}

.input-control:focus, .select-control:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(30, 95, 116, 0.15);
}

.input-sm {
  padding: 5px 8px;
  font-size: 0.82rem;
}

.slider-input-group {
  display: flex;
  align-items: center;
  gap: 12px;
}

.slider-input-group input[type="number"] {
  width: 78px;
  flex: 0 0 78px;
  text-align: right;
}

.range-slider {
  flex: 1;
  height: 6px;
  border-radius: 3px;
  background: #e2e8f0;
  outline: none;
  cursor: pointer;
  accent-color: var(--color-primary);
}

.checkbox-label {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.85rem;
  color: var(--color-text-secondary);
  cursor: pointer;
  user-select: none;
}

.checkbox-label input[type="checkbox"] {
  cursor: pointer;
  width: 16px;
  height: 16px;
  accent-color: var(--color-primary);
}

.checkbox-row {
  padding: 3px 0 1px 0;
}

.checkbox-label:hover {
  color: var(--color-text-primary);
}

/* -------------------------------------------------------------
 * Load Calculation Badge
 * ------------------------------------------------------------- */
.load-badge {
  background: #f8fafc;
  border: 1px solid #cbd5e1;
  border-radius: var(--radius-sm);
  padding: 6px 10px;
  font-size: 0.78rem;
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
  font-weight: 600;
  color: #1e293b;
  letter-spacing: 0.02em;
  display: inline-flex;
  align-items: center;
}

/* -------------------------------------------------------------
 * Price Card (Customer View)
 * ------------------------------------------------------------- */
.price-card {
  background: #f8fbfb;
  border: 1px solid #c7e0e7;
  border-radius: var(--radius-md);
  padding: 16px;
  display: flex;
  flex-direction: column;
  gap: 12px;
  box-shadow: var(--shadow-sm);
}

.price-title {
  margin: 0;
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--color-primary);
}

.price-rows {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.price-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.88rem;
  color: var(--color-text-secondary);
}

.price-value {
  font-weight: 600;
  color: var(--color-text-primary);
}

.price-divider {
  height: 1px;
  background: #e2e8f0;
  margin: 4px 0;
}

.total-row {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--color-text-primary);
}

.total-val {
  font-size: 1.15rem;
  font-weight: 800;
  color: var(--color-success);
}

.price-val-container {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  text-align: right;
}

.price-vat-sub {
  font-size: 0.72rem;
  font-weight: 500;
  color: var(--color-text-secondary);
  line-height: 1.2;
  margin-top: 1px;
}

.total-vat-sub {
  font-size: 0.76rem;
  font-weight: 600;
  color: var(--color-text-secondary);
  margin-top: 2px;
}

/* -------------------------------------------------------------
 * Buttons
 * ------------------------------------------------------------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-family: inherit;
  font-weight: 600;
  border: none;
  border-radius: var(--radius-sm);
  padding: 8px 14px;
  cursor: pointer;
  transition: all 0.15s ease-in-out;
}

.btn-primary {
  background: var(--color-primary);
  color: #ffffff;
}

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

.btn-order {
  padding: 10px 16px;
  font-size: 1rem;
}

.btn-secondary {
  background: #f1f5f9;
  color: var(--color-text-secondary);
  border: 1px solid var(--color-border);
}

.btn-secondary:hover {
  background: #e2e8f0;
  color: var(--color-text-primary);
}

.btn-spec-download {
  margin-top: 6px;
  font-size: 0.84rem;
  padding: 8px 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
}

.btn-danger {
  background: var(--color-danger-bg);
  color: var(--color-danger);
  border: 1px solid var(--color-danger-border);
}

.btn-danger:hover {
  background: var(--color-danger);
  color: #ffffff;
}

.btn-block {
  width: 100%;
}

.btn-sm {
  padding: 4px 8px;
  font-size: 0.78rem;
}

.btn-xs {
  padding: 2px 6px;
  font-size: 0.72rem;
}

.btn-glass {
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(8px);
  border: 1px solid rgba(255, 255, 255, 0.5);
  box-shadow: var(--shadow-md);
  color: var(--color-text-primary);
  font-size: 0.85rem;
}

.btn-glass:hover {
  background: rgba(255, 255, 255, 0.95);
}

/* -------------------------------------------------------------
 * Panels & Shelves UI
 * ------------------------------------------------------------- */
.panel-controls-card {
  margin-top: 6px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: #f8fafc;
  overflow: hidden;
}

.panel-toggle-btn {
  display: flex;
  justify-content: space-between;
  border: none;
  border-radius: 0;
  background: #f1f5f9;
  font-size: 0.82rem;
  padding: 8px 12px;
}

.panel-controls-content {
  padding: 10px;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.panel-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  align-items: center;
  gap: 8px;
}

.manual-shelves-container {
  display: flex;
  flex-direction: column;
  gap: 6px;
  margin-top: 6px;
  padding-left: 8px;
  border-left: 2px solid #cbd5e1;
}

.manual-shelf-row {
  display: flex;
  align-items: center;
  gap: 8px;
}

.manual-shelf-label {
  font-size: 0.78rem;
  color: var(--color-text-secondary);
}

/* -------------------------------------------------------------
 * Structural Engineering, Heatmap & Advisory
 * ------------------------------------------------------------- */
.load-badge {
  display: inline-block;
  font-size: 0.76rem;
  font-weight: 600;
  padding: 4px 8px;
  border-radius: var(--radius-sm);
  background: #f1f5f9;
  color: var(--color-text-secondary);
  border: 1px solid var(--color-border);
  margin-bottom: 8px;
  transition: all 0.2s ease;
}

.aspect-ratio-warning {
  display: flex;
  align-items: center;
  font-size: 0.76rem;
  font-weight: 500;
  line-height: 1.3;
  padding: 6px 10px;
  border-radius: var(--radius-sm);
  background: #fffbeb;
  color: #b45309;
  border: 1px solid #fde68a;
  margin-bottom: 8px;
}

.form-row-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 6px;
}

.input-unit-box {
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

.input-unit {
  font-size: 0.80rem;
  color: var(--color-text-secondary);
  font-weight: 600;
}

.form-hint {
  font-size: 0.74rem;
  color: var(--color-text-secondary);
  margin-top: 4px;
}

.range-slider {
  width: 100%;
  accent-color: var(--color-primary);
  cursor: pointer;
}

/* -------------------------------------------------------------
 * Modal Dialog
 * ------------------------------------------------------------- */
.modal-backdrop {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  background: rgba(15, 23, 42, 0.45);
  backdrop-filter: blur(4px);
  display: flex;
  justify-content: center;
  align-items: center;
  z-index: 1000;
}

.modal-dialog {
  background: #ffffff;
  border-radius: var(--radius-lg);
  width: 92%;
  max-width: 620px;
  box-shadow: var(--shadow-lg);
  display: flex;
  flex-direction: column;
  overflow: hidden;
  animation: modalIn 0.2s ease-out;
}

@keyframes modalIn {
  from { opacity: 0; transform: translateY(12px) scale(0.98); }
  to { opacity: 1; transform: translateY(0) scale(1); }
}

.modal-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 16px 20px;
  border-bottom: 1px solid var(--color-border);
}

.modal-title {
  margin: 0;
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--color-text-primary);
}

.modal-close-btn {
  background: transparent;
  border: none;
  font-size: 1.5rem;
  line-height: 1;
  color: var(--color-text-muted);
  cursor: pointer;
  padding: 0 4px;
}

.modal-close-btn:hover {
  color: var(--color-text-primary);
}

.modal-body {
  padding: 20px;
  display: flex;
  flex-direction: column;
  gap: 14px;
  max-height: 80vh;
  overflow-y: auto;
}

.modal-subtitle {
  margin: 0 0 6px 0;
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--color-text-secondary);
}

.modal-footer {
  display: flex;
  justify-content: flex-end;
  align-items: center;
  gap: 10px;
  padding: 14px 20px;
  border-top: 1px solid var(--color-border);
  background: #f8fafc;
}

.customer-type-toggle {
  display: flex;
  background: #f1f5f9;
  padding: 4px;
  border-radius: var(--radius-md);
  gap: 4px;
  margin-bottom: 14px;
  border: 1px solid var(--color-border);
}

.customer-type-btn {
  flex: 1;
  padding: 8px 12px;
  border: 1px solid transparent;
  background: transparent;
  border-radius: var(--radius-sm);
  font-size: 0.84rem;
  font-weight: 600;
  color: var(--color-text-secondary);
  cursor: pointer;
  transition: all 0.15s ease;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
}

.customer-type-btn:hover {
  color: var(--color-text-primary);
}

.customer-type-btn.active {
  background: #ffffff;
  color: var(--color-primary);
  border-color: rgba(30, 95, 116, 0.2);
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.08);
}

.delivery-toggle-container {
  margin-top: 8px;
  padding-top: 12px;
  border-top: 1px dashed var(--color-border);
}

.delivery-toggle-label {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--color-text-primary);
  cursor: pointer;
  user-select: none;
}

.delivery-address-card {
  margin-top: 10px;
  padding: 14px;
  background: #f8fafc;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.order-error-alert {
  padding: 10px 14px;
  background: var(--color-danger-bg);
  color: var(--color-danger);
  border: 1px solid var(--color-danger-border);
  border-radius: var(--radius-sm);
  font-size: 0.84rem;
  font-weight: 500;
  margin-top: 10px;
}

.form-notes-area {
  width: 100%;
  padding: 8px 10px;
  font-size: 0.86rem;
  font-family: inherit;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  resize: vertical;
  min-height: 52px;
  color: var(--color-text-primary);
  background: #ffffff;
}

.form-notes-area:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(30, 95, 116, 0.15);
}

/* -------------------------------------------------------------
 * Order Confirmation View
 * ------------------------------------------------------------- */
.confirmation-container {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  gap: 16px;
  padding: 8px 0;
}

.confirmation-hero-icon {
  width: 60px;
  height: 60px;
  border-radius: 50%;
  background: #ecfdf5;
  color: #10b981;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 2px solid #a7f3d0;
  box-shadow: 0 4px 14px rgba(16, 185, 129, 0.2);
}

.confirmation-hero-icon svg {
  width: 32px;
  height: 32px;
}

.confirmation-title {
  margin: 0;
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--color-text-primary);
}

.confirmation-subtitle {
  margin: 0;
  font-size: 0.88rem;
  color: var(--color-text-secondary);
  max-width: 480px;
  line-height: 1.45;
}

.confirmation-order-id-badge {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 8px 16px;
  background: #f8fafc;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  font-family: ui-monospace, monospace;
  font-weight: 700;
  font-size: 0.96rem;
  color: var(--color-primary);
}

.confirmation-order-id-badge code {
  color: var(--color-primary);
  font-size: 1.05rem;
}

.btn-copy-id {
  background: #ffffff;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  padding: 4px 8px;
  font-size: 0.76rem;
  font-family: inherit;
  font-weight: 600;
  color: var(--color-text-secondary);
  cursor: pointer;
  transition: all 0.15s ease;
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

.btn-copy-id:hover {
  background: var(--color-primary-light);
  color: var(--color-primary);
  border-color: var(--color-primary);
}

.confirmation-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
  width: 100%;
  text-align: left;
}

.confirmation-card {
  background: #f8fafc;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  padding: 12px 14px;
  display: flex;
  flex-direction: column;
  gap: 6px;
  font-size: 0.84rem;
}

.confirmation-card h4 {
  margin: 0 0 4px 0;
  font-size: 0.82rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--color-primary);
  border-bottom: 1px solid var(--color-border);
  padding-bottom: 4px;
}

.confirmation-steps-card {
  width: 100%;
  text-align: left;
  background: #f0fdf4;
  border: 1px solid #bbf7d0;
  border-radius: var(--radius-sm);
  padding: 14px;
  display: flex;
  flex-direction: column;
  gap: 6px;
  font-size: 0.83rem;
  color: #166534;
}

.confirmation-step-item {
  display: flex;
  align-items: flex-start;
  gap: 8px;
  line-height: 1.4;
}

.confirmation-step-num {
  background: #dcfce7;
  color: #15803d;
  font-weight: 700;
  font-size: 0.76rem;
  width: 18px;
  height: 18px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  margin-top: 1px;
}

.confirmation-step-note {
  margin-top: 6px;
  padding-top: 6px;
  border-top: 1px dashed #bbf7d0;
  display: flex;
  align-items: flex-start;
  gap: 7px;
  font-size: 0.78rem;
  color: #15803d;
  line-height: 1.35;
  font-weight: 500;
}

.confirmation-step-note svg {
  width: 14px;
  height: 14px;
  flex-shrink: 0;
  margin-top: 1px;
  color: #16a34a;
}

.modal-actions {
  display: flex;
  justify-content: flex-end;
  gap: 10px;
  margin-top: 10px;
  padding-top: 14px;
  border-top: 1px solid var(--color-border);
}

.alert {
  padding: 10px 12px;
  border-radius: var(--radius-sm);
  font-size: 0.85rem;
}

.alert-danger {
  background: var(--color-danger-bg);
  color: var(--color-danger);
  border: 1px solid var(--color-danger-border);
}

/* -------------------------------------------------------------
 * Header Actions & Share Button
 * ------------------------------------------------------------- */
.header-actions {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  gap: 10px;
}

#share-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: #f8fafc;
  border: 1px solid var(--color-border);
  color: var(--color-text-secondary);
  font-size: 0.8rem;
  font-weight: 600;
  padding: 5px 12px;
  border-radius: var(--radius-md);
  cursor: pointer;
  white-space: nowrap;
  flex-shrink: 0;
  transition: all 0.2s ease;
}

#share-btn:hover {
  background: var(--color-primary-light);
  color: var(--color-primary);
  border-color: var(--color-primary);
}

/* -------------------------------------------------------------
 * 3D Viewport & Overlays
 * ------------------------------------------------------------- */
#view3d {
  flex: 1;
  position: relative;
  height: 100vh;
  overflow: hidden;
  background: #f4f6f8;
}

.viewport-overlay {
  position: absolute;
  top: auto;
  bottom: 24px;
  right: 24px;
  left: auto;
  width: auto;
  height: auto;
  z-index: 15;
  display: flex;
  flex-direction: row;
  align-items: center;
  gap: 8px;
  background: rgba(255, 255, 255, 0.75);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  padding: 6px 8px;
  border-radius: var(--radius-lg);
  border: 1px solid rgba(226, 232, 240, 0.9);
  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.07);
  white-space: nowrap;
}

.btn-glass {
  background: rgba(255, 255, 255, 0.88);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border: 1px solid rgba(226, 232, 240, 0.9);
  color: var(--color-text-primary);
  box-shadow: 0 2px 6px rgba(0, 0, 0, 0.04);
  padding: 7px 12px;
  font-size: 0.80rem;
  font-weight: 600;
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all 0.2s ease;
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.btn-glass:hover {
  background: rgba(255, 255, 255, 0.98);
  border-color: var(--color-primary);
  color: var(--color-primary);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
  transform: translateY(-1px);
}

.btn-glass.active {
  background: var(--color-primary-light);
  border-color: var(--color-primary);
  color: var(--color-primary);
  box-shadow: 0 0 0 1px var(--color-primary);
  font-weight: 700;
}

/* -------------------------------------------------------------
 * Preset Templates Bar & Expand Pill
 * ------------------------------------------------------------- */
#preset-bar-container {
  position: absolute;
  top: 16px;
  left: 20px;
  right: 20px;
  z-index: 20;
  pointer-events: none;
}

.preset-bar {
  pointer-events: auto;
  background: rgba(255, 255, 255, 0.94);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid rgba(226, 232, 240, 0.9);
  border-radius: var(--radius-lg);
  padding: 12px 16px;
  box-shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.08), 0 8px 10px -6px rgba(0, 0, 0, 0.04);
  transition: transform 0.3s cubic-bezier(0.16, 1, 0.3, 1), opacity 0.25s ease, visibility 0.25s;
  transform: translateY(0);
  opacity: 1;
  visibility: visible;
}

.preset-bar.collapsed {
  transform: translateY(-20px);
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
}

.preset-bar-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 10px;
}

.preset-bar-title-group {
  display: flex;
  align-items: center;
  gap: 6px;
}

.preset-bar-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  color: var(--color-primary);
}

.preset-bar-icon .ui-icon {
  width: 1.15rem;
  height: 1.15rem;
}

.preset-bar-title {
  font-size: 0.82rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--color-text-primary);
  text-transform: uppercase;
}

.btn-ghost {
  background: transparent;
  border: none;
  color: var(--color-text-muted);
  cursor: pointer;
  padding: 4px 8px;
  border-radius: var(--radius-sm);
  font-size: 0.85rem;
  transition: background 0.15s ease;
}

.btn-ghost:hover {
  background: #f1f5f9;
  color: var(--color-text-primary);
}

.preset-cards-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 10px;
}

.preset-card {
  background: #ffffff;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 10px 12px;
  cursor: pointer;
  transition: all 0.2s cubic-bezier(0.16, 1, 0.3, 1);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  gap: 8px;
}

.preset-card:hover {
  border-color: var(--color-primary);
  box-shadow: 0 4px 12px rgba(30, 95, 116, 0.12);
  transform: translateY(-2px);
}

.preset-card.active {
  border-color: var(--color-primary);
  background: var(--color-primary-light);
  box-shadow: 0 0 0 1px var(--color-primary);
}

.preset-card-header {
  display: flex;
  align-items: flex-start;
  gap: 8px;
}

.preset-card-icon {
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-primary);
  flex-shrink: 0;
}

.preset-card-icon .ui-icon {
  width: 1.4rem;
  height: 1.4rem;
}

.preset-card-text {
  display: flex;
  flex-direction: column;
  gap: 2px;
  overflow: hidden;
}

.preset-title {
  font-size: 0.84rem;
  font-weight: 700;
  color: var(--color-text-primary);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.preset-sub {
  font-size: 0.72rem;
  color: var(--color-text-secondary);
  line-height: 1.25;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.preset-specs-pill {
  font-size: 0.68rem;
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
  background: #f8fafc;
  color: var(--color-text-secondary);
  border: 1px solid var(--color-border);
  padding: 3px 6px;
  border-radius: 4px;
  text-align: center;
  font-weight: 600;
}

.preset-card.active .preset-specs-pill {
  background: #ffffff;
  color: var(--color-primary);
  border-color: rgba(30, 95, 116, 0.3);
}

/* Floating Expand Pill */
.preset-expand-pill {
  pointer-events: auto;
  position: absolute;
  top: 0;
  left: 0;
  opacity: 0;
  visibility: hidden;
  transform: translateY(-10px);
  transition: all 0.25s cubic-bezier(0.16, 1, 0.3, 1);
}

.preset-expand-pill.visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

/* -------------------------------------------------------------
 * Mobile Splash Screen
 * ------------------------------------------------------------- */
.mobile-splash-overlay {
  position: fixed;
  inset: 0;
  background: rgba(15, 23, 42, 0.85);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  z-index: 1000;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
  animation: fadeIn 0.3s ease;
  transition: opacity 0.3s ease, visibility 0.3s;
}

.mobile-splash-overlay.fading-out {
  opacity: 0;
  visibility: hidden;
}

.mobile-splash-card {
  background: #ffffff;
  border-radius: var(--radius-lg);
  max-width: 420px;
  width: 100%;
  padding: 28px 24px;
  text-align: center;
  box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.2), 0 10px 10px -5px rgba(0, 0, 0, 0.1);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 14px;
}

.mobile-splash-icon {
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-primary);
}

.mobile-splash-icon .ui-icon {
  width: 3.5rem;
  height: 3.5rem;
}

.mobile-splash-title {
  margin: 0;
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--color-text-primary);
}

.mobile-splash-desc {
  margin: 0;
  font-size: 0.92rem;
  line-height: 1.5;
  color: var(--color-text-secondary);
}

/* -------------------------------------------------------------
 * Toast Notification
 * ------------------------------------------------------------- */
.toast-notification {
  position: fixed;
  bottom: 24px;
  left: 50%;
  transform: translateX(-50%) translateY(30px);
  background: rgba(15, 23, 42, 0.95);
  backdrop-filter: blur(8px);
  color: #ffffff;
  padding: 10px 20px;
  border-radius: 9999px;
  font-size: 0.86rem;
  font-weight: 600;
  box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.2);
  z-index: 2000;
  opacity: 0;
  visibility: hidden;
  transition: all 0.25s cubic-bezier(0.16, 1, 0.3, 1);
  pointer-events: none;
}

.toast-notification.show {
  opacity: 1;
  visibility: visible;
  transform: translateX(-50%) translateY(0);
}

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

/* -------------------------------------------------------------
 * Clean Embed Mode (for screenshots & embedded 3D viewer)
 * ------------------------------------------------------------- */
body.clean-embed-mode #sidebar,
body.clean-embed-mode .viewport-overlay,
body.clean-embed-mode #preset-bar-container {
  display: none !important;
}

body.clean-embed-mode #main {
  display: block !important;
  width: 100vw !important;
  height: 100vh !important;
}

body.clean-embed-mode #view3d {
  width: 100vw !important;
  height: 100vh !important;
}

/* -------------------------------------------------------------
 * App Startup Loading Overlay (Example 2: Staggered Letter Assembly)
 * ------------------------------------------------------------- */
.app-loader {
  position: fixed;
  inset: 0;
  width: 100vw;
  height: 100vh;
  background: rgba(9, 13, 22, 0.94);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  z-index: 99999;
  opacity: 1;
  visibility: visible;
  transition: opacity 0.5s cubic-bezier(0.16, 1, 0.3, 1), visibility 0.5s cubic-bezier(0.16, 1, 0.3, 1);
  cursor: pointer;
  --abl-duration: 3.2s;
  --abl-color: #f8fafc;
}

.app-loader.fading-out {
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
}

.app-loader .overlay-content {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 22px;
  max-width: 480px;
  width: 90%;
  text-align: center;
}

.app-loader .loader-logo-wrap {
  width: 100%;
  max-width: 440px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.app-loader .loader-logo-img {
  width: 100%;
  max-width: 440px;
  height: auto;
  max-height: 56px;
  display: block;
}

.app-loader .abl-letters-reveal {
  width: 100%;
  height: auto;
  max-height: 56px;
  display: block;
  background: transparent;
  color: var(--abl-color, #f8fafc);
  overflow: visible;
}

.app-loader .abl-char {
  stroke: currentColor;
  stroke-width: 1.3px;
  stroke-linecap: round;
  stroke-linejoin: round;
  fill: currentColor;
  fill-opacity: 0;
  opacity: 0;
  animation: abl-char-seq var(--abl-duration, 3.2s) cubic-bezier(0.25, 1, 0.5, 1) infinite;
  filter: url(#abl-char-glow);
}

.app-loader .abl-char-0 { stroke-dasharray: 304.9; stroke-dashoffset: 304.9; animation-delay: 0.0s; }
.app-loader .abl-char-1 { stroke-dasharray: 349.9; stroke-dashoffset: 349.9; animation-delay: 0.12s; }
.app-loader .abl-char-2 { stroke-dasharray: 187.7; stroke-dashoffset: 187.7; animation-delay: 0.24s; }
.app-loader .abl-char-3 { stroke-dasharray: 326.4; stroke-dashoffset: 326.4; animation-delay: 0.42s; }
.app-loader .abl-char-4 { stroke-dasharray: 201.6; stroke-dashoffset: 201.6; animation-delay: 0.49s; }
.app-loader .abl-char-5 { stroke-dasharray: 298.4; stroke-dashoffset: 298.4; animation-delay: 0.56s; }
.app-loader .abl-char-6 { stroke-dasharray: 126.5; stroke-dashoffset: 126.5; animation-delay: 0.63s; }
.app-loader .abl-char-7 { stroke-dasharray: 201.6; stroke-dashoffset: 201.6; animation-delay: 0.70s; }
.app-loader .abl-char-8 { stroke-dasharray: 241.5; stroke-dashoffset: 241.5; animation-delay: 0.77s; }
.app-loader .abl-char-9 { stroke-dasharray: 241.5; stroke-dashoffset: 241.5; animation-delay: 0.84s; }
.app-loader .abl-char-10 { stroke-dasharray: 133.4; stroke-dashoffset: 133.4; animation-delay: 0.91s; }
.app-loader .abl-char-11 { stroke-dasharray: 126.5; stroke-dashoffset: 126.5; animation-delay: 0.98s; }
.app-loader .abl-char-12 { stroke-dasharray: 201.6; stroke-dashoffset: 201.6; animation-delay: 1.05s; }
.app-loader .abl-char-13 { stroke-dasharray: 298.4; stroke-dashoffset: 298.4; animation-delay: 1.12s; }

@keyframes abl-char-seq {
  0% {
    stroke-dashoffset: 360;
    fill-opacity: 0;
    opacity: 0;
    transform: translateY(2.5px);
  }
  6% {
    opacity: 1;
    transform: translateY(0);
  }
  34% {
    stroke-dashoffset: 0;
    fill-opacity: 0;
  }
  48% {
    stroke-dashoffset: 0;
    fill-opacity: 1;
    opacity: 1;
  }
  82% {
    stroke-dashoffset: 0;
    fill-opacity: 1;
    opacity: 1;
  }
  95%, 100% {
    stroke-dashoffset: 0;
    fill-opacity: 0;
    opacity: 0;
  }
}

.app-loader .overlay-progress-track {
  width: 220px;
  height: 3px;
  background: rgba(255, 255, 255, 0.12);
  border-radius: 3px;
  overflow: hidden;
  position: relative;
}

.app-loader .overlay-progress-bar {
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, #38bdf8, transparent);
  animation: progress-loop 1.6s ease-in-out infinite;
}

@keyframes progress-loop {
  0% { transform: translateX(-100%); }
  100% { transform: translateX(100%); }
}

.app-loader .overlay-text {
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.15em;
  color: #94a3b8;
  text-transform: uppercase;
  font-family: var(--font-family);
}