/* ============================================================
   LAYOUT — positioning & structure
   How the major UI regions sit on screen.
   ============================================================ */

* { box-sizing: border-box; margin: 0; padding: 0; }

html, body {
  height: 100%;
  overflow: hidden;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Helvetica Neue", sans-serif;
  font-size: 13px;
  line-height: 1.4;
  color: var(--text-primary);
  background: var(--bg-canvas);
  transition: background-color 0.25s ease;
}

/* ---- 3D canvas ---- */
#canvas-container {
  position: fixed;
  top: 0; left: 0;
  width: 100%;
  height: 100%;
  z-index: 1;
}

/* Cursor styles per active tool */
body[data-tool="pan"]      #canvas-container { cursor: grab; }
body[data-tool="pan"].dragging #canvas-container { cursor: grabbing; }
body[data-tool="distance"] #canvas-container,
body[data-tool="area"]     #canvas-container,
body[data-tool="angle"]    #canvas-container { cursor: crosshair; }
body[data-tool="edit"]     #canvas-container,
body[data-tool="delete"]   #canvas-container { cursor: pointer; }

/* ---- Top bar (file picker + branding) ---- */
#topbar {
  position: fixed;
  top: 12px; left: 12px; right: 12px;
  z-index: 10;
  display: flex;
  align-items: center;
  gap: 12px;
  pointer-events: none;
}
#topbar > * { pointer-events: auto; }

/* ---- Left toolbar ---- */
#toolbar {
  position: fixed;
  left: 12px;
  top: 50%;
  transform: translateY(-50%);
  z-index: 10;
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 6px;
  background: var(--bg-toolbar);
  border: 1px solid var(--border-subtle);
  border-radius: 10px;
  box-shadow: var(--shadow);
  backdrop-filter: blur(12px);
  background-color: color-mix(in srgb, var(--bg-toolbar) 90%, transparent);
}

.tool-divider {
  height: 1px;
  margin: 4px 6px;
  background: var(--border-subtle);
}

/* ---- Bottom status bar ---- */
#statusbar {
  position: fixed;
  bottom: 12px;
  left: 50%;
  transform: translateX(-50%);
  z-index: 10;
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 8px 16px;
  background: var(--bg-panel);
  border: 1px solid var(--border-subtle);
  border-radius: 8px;
  box-shadow: var(--shadow-soft);
  backdrop-filter: blur(12px);
  background-color: color-mix(in srgb, var(--bg-panel) 85%, transparent);
  min-width: 320px;
  max-width: 80vw;
  transition: opacity 0.2s, transform 0.2s;
}

.status-divider {
  width: 1px;
  height: 14px;
  background: var(--border-subtle);
}

/* ---- Right panel (slides in from right) ---- */
#panel-toggle {
  position: fixed;
  right: 12px;
  top: 50%;
  transform: translateY(-50%);
  z-index: 11;
  width: 32px;
  height: 60px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--bg-panel);
  border: 1px solid var(--border-subtle);
  border-right: none;
  border-radius: 8px 0 0 8px;
  color: var(--text-secondary);
  cursor: pointer;
  transition: all 0.2s ease;
  box-shadow: var(--shadow-soft);
}

#panel-toggle:hover {
  background: var(--bg-panel-hover);
  color: var(--text-primary);
}

body.panel-open #panel-toggle {
  right: 300px;
}

#right-panel {
  position: fixed;
  right: 0;
  top: 0;
  bottom: 0;
  width: 300px;
  z-index: 10;
  background: var(--bg-panel);
  border-left: 1px solid var(--border-subtle);
  box-shadow: var(--shadow);
  transform: translateX(100%);
  transition: transform 0.25s cubic-bezier(0.4, 0, 0.2, 1);
  display: flex;
  flex-direction: column;
  backdrop-filter: blur(12px);
  background-color: color-mix(in srgb, var(--bg-panel) 95%, transparent);
}

body.panel-open #right-panel {
  transform: translateX(0);
}

.panel-header {
  padding: 16px 18px 12px;
  border-bottom: 1px solid var(--border-subtle);
}

.panel-body {
  flex: 1;
  overflow-y: auto;
  padding: 16px 18px;
}

/* ---- Loading overlay ---- */
#loading {
  position: fixed;
  top: 50%; left: 50%;
  transform: translate(-50%, -50%);
  z-index: 100;
  padding: 14px 22px;
  background: var(--bg-panel);
  border: 1px solid var(--border-subtle);
  border-radius: 8px;
  color: var(--text-primary);
  font-size: 13px;
  box-shadow: var(--shadow);
  display: none;
  align-items: center;
  gap: 10px;
}

#loading.visible { display: flex; }

/* ---- Mobile responsive ---- */
@media (max-width: 600px) {
  #toolbar {
    flex-direction: row;
    left: 50%;
    top: auto;
    bottom: 60px;
    transform: translateX(-50%);
  }
  #statusbar {
    bottom: 12px;
    min-width: auto;
    width: calc(100% - 24px);
    font-size: 11px;
  }
  #right-panel { width: 100%; }
  body.panel-open #panel-toggle { right: calc(100% - 32px); }
}