/* ===== DESIGN TOKENS ===== */
:root {
  --color-bg: #FFFAF5;
  --color-surface: #FFFCF7;
  --color-surface-variant: #F5F0E8;
  --color-primary: #B5506B;
  --color-primary-hover: #9A4059;
  --color-primary-container: #F4D0DB;
  --color-on-primary: #FFFFFF;
  --color-outline: #D4C9BD;
  --color-outline-variant: #EAE3D9;
  --color-on-surface: #2D2620;
  --color-on-surface-variant: #76705F;
  --color-error: #D85C5C;
  --color-error-bg: #FFF0F0;
  --shadow-sm: 0 1px 2px rgba(45,38,32,0.06);
  --shadow-md: 0 2px 6px rgba(45,38,32,0.1);
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 18px;
  --sidebar-width: 272px;
  --font-body: 'Poppins', system-ui, sans-serif;
  --font-mono: 'DM Mono', monospace;
  --color-primary-focus-ring: rgba(181, 80, 107, 0.12);
  --color-canvas-hint-bg:     rgba(255, 252, 247, 0.92);
  --color-overlay:            rgba(45, 38, 32, 0.45);
}

/* ===== RESET & BASE ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html, body {
  height: 100%;
  font-family: var(--font-body);
  font-size: 13.5px;
  color: var(--color-on-surface);
  background: var(--color-bg);
  overflow: hidden;
}

body {
  display: flex;
}

/* ===== SIDEBAR ===== */
#sidebar {
  width: var(--sidebar-width);
  min-width: var(--sidebar-width);
  height: 100vh;
  background: var(--color-surface);
  border-right: 1px solid var(--color-outline-variant);
  box-shadow: 1px 0 4px rgba(45,38,32,0.08);
  display: flex;
  flex-direction: column;
  overflow-y: auto;
  overflow-x: hidden;
  z-index: 10;
  transition: transform 0.3s ease, visibility 0.3s ease;
}

#sidebar.hidden {
  transform: translateX(-100%);
  visibility: hidden;
}

.sidebar-header {
  padding: 18px 18px 14px;
  border-bottom: 1px solid var(--color-outline-variant);
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
}

.btn-toggle-sidebar {
  background: none;
  border: none;
  font-size: 20px;
  color: var(--color-primary);
  cursor: pointer;
  padding: 4px 6px;
  line-height: 1;
  transition: color 0.2s;
  flex-shrink: 0;
}

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

.logo-group {
  display: flex;
  flex-direction: row;
  align-items: center;
  gap: 4px;
}
.logo-icon {
  height: 40px;
  width: 40px;
  flex-shrink: 0;
}
.logo-text {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.logo {
  font-family: var(--font-body);
  font-size: 18px;
  font-weight: 600;
  color: var(--color-primary);
  letter-spacing: 0.05em;
  font-style: italic;
  line-height: 1;
}

.logo-sub {
  font-size: 11px;
  font-weight: 400;
  color: var(--color-on-surface-variant);
  letter-spacing: 0.01em;
}

/* ===== SIDEBAR SECTIONS ===== */
.sidebar-section {
  padding: 14px 16px;
  border-bottom: 1px solid var(--color-outline-variant);
}

.section-title {
  font-size: 10.5px;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-on-surface-variant);
  margin-bottom: 10px;
}
.section-details > summary.section-title {
  cursor: pointer;
  list-style: none;
  user-select: none;
  display: flex;
  align-items: center;
  gap: 5px;
  color: var(--color-primary);
}
.section-details > summary.section-title::-webkit-details-marker { display: none; }
.section-details > summary.section-title::after {
  content: '▾';
  font-size: 10px;
  opacity: 0.5;
  transition: transform 0.15s;
  margin-left: auto;
}
.section-details:not([open]) > summary.section-title::after {
  transform: rotate(-90deg);
}

/* ===== TABS ===== */
.room-mode-tabs {
  display: flex;
  gap: 4px;
  background: var(--color-surface-variant);
  border-radius: var(--radius-md);
  padding: 3px;
  margin-bottom: 10px;
}

.tab-btn {
  flex: 1;
  padding: 5px 8px;
  border: none;
  border-radius: calc(var(--radius-md) - 2px);
  background: transparent;
  color: var(--color-on-surface-variant);
  font-family: var(--font-body);
  font-size: 12.5px;
  font-weight: 500;
  cursor: pointer;
  transition: background 0.12s, color 0.12s;
}

.tab-btn.active {
  background: var(--color-surface);
  color: var(--color-on-surface);
  box-shadow: var(--shadow-sm);
}

.tab-btn:hover:not(.active) {
  background: rgba(0,0,0,0.04);
}

/* ===== HINTS ===== */
.hint {
  font-size: 12px;
  color: var(--color-on-surface-variant);
  line-height: 1.5;
  margin-bottom: 8px;
}
.io-hint {
  font-size: 11px;
  color: var(--color-on-surface-variant);
  margin: 6px 0 0;
  opacity: 0.7;
}

/* ===== INPUTS ===== */
input[type="number"],
input[type="text"],
select {
  width: 100%;
  padding: 7px 10px;
  border: 1px solid var(--color-outline);
  border-radius: var(--radius-md);
  background: var(--color-surface);
  font-family: var(--font-body);
  font-size: 13px;
  color: var(--color-on-surface);
  outline: none;
  transition: border-color 0.12s, box-shadow 0.12s;
  margin-top: 3px;
}

input[type="number"]:focus,
input[type="text"]:focus,
select:focus {
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px var(--color-primary-focus-ring);
}

label {
  display: block;
  font-size: 12px;
  font-weight: 500;
  color: var(--color-on-surface-variant);
  margin-bottom: 8px;
}

.unit {
  font-weight: 400;
  color: var(--color-on-surface-variant);
  font-size: 11px;
}

.input-row {
  display: flex;
  gap: 8px;
}

.input-row label {
  flex: 1;
}

.inline-label {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 12px;
  font-weight: 500;
  color: var(--color-on-surface-variant);
  margin-bottom: 8px;
  gap: 8px;
}

.inline-label input {
  width: 64px;
  flex-shrink: 0;
  margin-top: 0;
  text-align: right;
}

/* ===== RADIO ===== */
.radio-label {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 12.5px;
  font-weight: 400;
  color: var(--color-on-surface);
  cursor: pointer;
  margin-bottom: 0;
}

input[type="radio"] {
  accent-color: var(--color-primary);
  width: 14px;
  height: 14px;
}

/* ===== BUTTONS ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 5px;
  padding: 7px 14px;
  border-radius: var(--radius-md);
  font-family: var(--font-body);
  font-size: 12.5px;
  font-weight: 500;
  cursor: pointer;
  border: none;
  transition: background 0.12s, box-shadow 0.12s, transform 0.08s;
  white-space: nowrap;
}

.btn:active { transform: translateY(1px); }

.btn-primary {
  background: var(--color-primary);
  color: var(--color-on-primary);
}
.btn-primary:hover { background: var(--color-primary-hover); }
.btn-primary.active { background: var(--color-primary-hover); box-shadow: inset 0 0 0 1px var(--color-primary); }

.btn-outline {
  background: transparent;
  color: var(--color-on-surface);
  border: 1px solid var(--color-outline);
}
.btn-outline:hover { background: var(--color-surface-variant); }
.btn-outline.active { background: var(--color-primary-container); color: var(--color-primary); border-color: var(--color-primary); }

.btn-danger { color: var(--color-error) !important; border-color: var(--color-error) !important; }
.btn-danger:hover { background: var(--color-error-bg) !important; }

.btn-sm {
  padding: 5px 10px;
  font-size: 12px;
}

.action-row {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
  margin-top: 6px;
}

.color-row {
  display: flex;
  align-items: center;
  gap: 6px;
  margin-top: 4px;
}

.color-label {
  font-size: 12px;
  font-weight: 500;
  color: var(--color-on-surface-variant);
  margin: 0;
  flex: 1;
}

input[type="color"] {
  width: 32px;
  height: 22px;
  padding: 1px 2px;
  border: 1px solid var(--color-outline);
  border-radius: 4px;
  background: var(--color-surface);
  cursor: pointer;
  opacity: 0.7;
  flex-shrink: 0;
}

input[type="color"]::-webkit-color-swatch-wrapper { padding: 0; }
input[type="color"]::-webkit-color-swatch { border: none; border-radius: 2px; }

.btn-icon-sm {
  padding: 3px 7px;
  font-size: 13px;
  line-height: 1;
}

.action-col {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

/* ===== FILE BUTTON ===== */
.file-btn {
  cursor: pointer;
  text-align: center;
}

/* ===== DIVIDER ===== */
.divider {
  height: 1px;
  background: var(--color-outline-variant);
  margin: 10px 0;
}

/* ===== TOGGLE ===== */
.toggle-label {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 12px;
  font-weight: 500;
  color: var(--color-on-surface-variant);
  margin-bottom: 8px;
  cursor: pointer;
}

.toggle {
  position: relative;
  display: inline-block;
  width: 40px;
  height: 22px;
  flex-shrink: 0;
}

.toggle input { opacity: 0; width: 0; height: 0; }

.toggle-track {
  position: absolute;
  inset: 0;
  border-radius: 20px;
  background: var(--color-outline);
  transition: background 0.2s;
  cursor: pointer;
}

.toggle-track::before {
  content: '';
  position: absolute;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: white;
  top: 3px;
  left: 3px;
  transition: transform 0.2s;
  box-shadow: 0 1px 2px rgba(45,38,32,0.15);
}

.toggle input:checked + .toggle-track { background: var(--color-primary); }
.toggle input:checked + .toggle-track::before { transform: translateX(16px); }

/* ===== COLLAPSIBLE ===== */
.collapsible summary {
  font-size: 12px;
  font-weight: 500;
  color: var(--color-primary);
  cursor: pointer;
  list-style: none;
  padding: 4px 0;
  user-select: none;
}
.collapsible summary::-webkit-details-marker { display: none; }
.collapsible summary::before {
  content: '+ ';
  font-weight: 600;
}
.collapsible[open] summary::before { content: '− '; }

.custom-form {
  margin-top: 10px;
  display: flex;
  flex-direction: column;
  gap: 6px;
}

/* ===== FURNITURE CATALOG ===== */
#furniture-catalog {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.catalog-category {
  border-radius: var(--radius-md);
  overflow: hidden;
  border: 1px solid var(--color-outline-variant);
}

.catalog-category-header {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 7px 10px;
  background: var(--color-surface-variant);
  cursor: pointer;
  user-select: none;
}

.catalog-category-header:hover { background: var(--color-surface-variant); }

.category-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  flex-shrink: 0;
}

.catalog-category-name {
  font-size: 12px;
  font-weight: 500;
  flex: 1;
}

.catalog-category-arrow {
  font-size: 10px;
  color: var(--color-on-surface-variant);
  transition: transform 0.15s;
}

.catalog-category.open .catalog-category-arrow { transform: rotate(90deg); }

.catalog-items {
  display: none;
  padding: 4px;
  gap: 3px;
  flex-direction: column;
}

.catalog-category.open .catalog-items { display: flex; }

.catalog-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 5px 8px;
  border-radius: calc(var(--radius-md) - 2px);
  cursor: pointer;
  transition: background 0.12s;
  gap: 8px;
}

.catalog-item:hover { background: var(--color-primary-container); }

.catalog-item-name {
  font-size: 12.5px;
  flex: 1;
}

.catalog-item-size {
  font-family: var(--font-mono);
  font-size: 10.5px;
  color: var(--color-on-surface-variant);
}

/* ===== SELECTED SECTION ===== */
.section-selected-panel {
  background: var(--color-primary-container);
  border-bottom: 2px solid var(--color-primary);
}

.section-selected-panel .section-title {
  color: var(--color-primary);
}

.section-selected-panel input,
.section-selected-panel select {
  background: var(--color-surface);
}

.selected-name {
  font-size: 13px;
  font-weight: 600;
  margin-bottom: 10px;
  color: var(--color-on-surface);
}

/* ===== CANVAS AREA ===== */
#canvas-wrapper {
  flex: 1;
  position: relative;
  overflow: hidden;
  background: var(--color-bg);
}

#room-canvas {
  position: absolute;
  top: 0;
  left: 0;
  cursor: crosshair;
  touch-action: none;
}

#room-canvas.cursor-grab { cursor: grab; }
#room-canvas.cursor-grabbing { cursor: grabbing; }
#room-canvas.cursor-move { cursor: move; }
#room-canvas.cursor-default { cursor: default; }
#room-canvas.cursor-ew-resize { cursor: ew-resize; }
#room-canvas.cursor-ns-resize { cursor: ns-resize; }

.btn-show-sidebar {
  position: absolute;
  top: 20px;
  left: 20px;
  z-index: 9;
  width: 40px;
  height: 40px;
  border-radius: var(--radius-md);
  background: var(--color-surface);
  border: 1px solid var(--color-outline);
  color: var(--color-primary);
  font-size: 20px;
  cursor: pointer;
  transition: background 0.2s, transform 0.2s;
  box-shadow: var(--shadow-md);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 0;
}

.btn-show-sidebar:hover {
  background: var(--color-surface-variant);
  transform: scale(1.05);
}

.btn-show-sidebar.hidden {
  display: none;
}

.canvas-hint {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  font-size: 13px;
  color: var(--color-on-surface-variant);
  pointer-events: none;
  text-align: center;
  padding: 14px 24px;
  background: var(--color-canvas-hint-bg);
  border-radius: var(--radius-lg);
  box-shadow: 0 2px 8px rgba(45,38,32,0.08);
  backdrop-filter: blur(4px);
  max-width: 240px;
  line-height: 1.6;
  transition: opacity 0.3s;
  border: 1px solid rgba(212,201,189,0.3);
}

.canvas-hint.hidden { opacity: 0; pointer-events: none; }

/* ===== SIDEBAR FOOTER ===== */
.sidebar-footer {
  margin-top: auto;
  padding: 12px 16px;
  border-top: 1px solid var(--color-outline-variant);
  flex-shrink: 0;
}

.btn-info {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  background: none;
  border: none;
  cursor: pointer;
  font-family: var(--font-body);
  font-size: 12px;
  font-weight: 500;
  color: var(--color-primary);
  padding: 5px 8px;
  border-radius: var(--radius-sm);
  transition: background 0.15s, color 0.15s;
  width: 100%;
}

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

.btn-info-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 18px;
  height: 18px;
  border-radius: 50%;
  border: 1.5px solid currentColor;
  font-size: 11px;
  font-weight: 600;
  font-style: italic;
  flex-shrink: 0;
  line-height: 1;
}

/* ===== ABOUT OVERLAY ===== */
.about-overlay {
  position: fixed;
  inset: 0;
  background: var(--color-overlay);
  backdrop-filter: blur(3px);
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
  animation: overlay-in 0.18s ease;
}

.about-overlay.hidden { display: none !important; }

@keyframes overlay-in {
  from { opacity: 0; }
  to   { opacity: 1; }
}

.about-card {
  background: var(--color-surface);
  border-radius: var(--radius-lg);
  box-shadow: 0 12px 40px rgba(45,38,32,0.22);
  padding: 32px 36px;
  max-width: 520px;
  width: 100%;
  max-height: 88vh;
  overflow-y: auto;
  position: relative;
  animation: card-in 0.2s cubic-bezier(0.34,1.3,0.64,1);
}

@keyframes card-in {
  from { transform: scale(0.93) translateY(8px); opacity: 0; }
  to   { transform: scale(1)    translateY(0);   opacity: 1; }
}

.about-close {
  position: absolute;
  top: 16px;
  right: 16px;
  background: none;
  border: none;
  font-size: 15px;
  color: var(--color-on-surface-variant);
  cursor: pointer;
  padding: 4px 7px;
  border-radius: var(--radius-sm);
  line-height: 1;
  transition: background 0.15s;
}
.about-close:hover { background: var(--color-surface-variant); }

.about-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 6px;
}
.about-logo-icon {
  width: 36px;
  height: 36px;
}
.about-logo-name {
  font-size: 22px;
  font-weight: 600;
  font-style: italic;
  color: var(--color-primary);
  letter-spacing: 0.04em;
  font-family: var(--font-body);
}
.about-tagline {
  font-size: 13px;
  color: var(--color-on-surface-variant);
  margin-bottom: 24px;
}

.about-section {
  margin-bottom: 22px;
}
.about-section h3 {
  font-size: 10.5px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-on-surface-variant);
  margin-bottom: 10px;
}
.about-section p {
  font-size: 13px;
  line-height: 1.65;
  color: var(--color-on-surface);
}

.about-steps {
  padding-left: 18px;
  display: flex;
  flex-direction: column;
  gap: 7px;
}
.about-steps li {
  font-size: 13px;
  line-height: 1.55;
  color: var(--color-on-surface);
}

.about-keys {
  display: flex;
  flex-direction: column;
  gap: 5px;
}
.about-keys > div {
  display: flex;
  align-items: baseline;
  gap: 10px;
}
.about-keys dt {
  min-width: 110px;
  flex-shrink: 0;
  display: flex;
  gap: 4px;
  flex-wrap: wrap;
}
.about-keys dd {
  font-size: 12.5px;
  color: var(--color-on-surface);
}

kbd {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 11px;
  padding: 1px 5px;
  border: 1px solid var(--color-outline);
  border-radius: 4px;
  background: var(--color-surface-variant);
  color: var(--color-on-surface);
  white-space: nowrap;
}

.about-meta {
  border-top: 1px solid var(--color-outline-variant);
  padding-top: 18px;
}
.about-links {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  margin-bottom: 12px;
}
.about-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 13px;
  font-weight: 500;
  color: var(--color-primary);
  text-decoration: none;
  padding: 5px 10px;
  border: 1px solid var(--color-primary-container);
  border-radius: var(--radius-sm);
  transition: background 0.15s;
}
.about-link:hover { background: var(--color-primary-container); }
.about-link svg {
  width: 14px;
  height: 14px;
  fill: currentColor;
  flex-shrink: 0;
}
.about-credit {
  font-size: 12px;
  color: var(--color-on-surface-variant);
}
.about-credit a {
  color: var(--color-primary);
  text-decoration: none;
}
.about-credit a:hover { text-decoration: underline; }

/* ===== UTILITIES ===== */
.hidden { display: none !important; }