/* Drawing Language Editor — CAD-inspired dark UI, restrained accent, dense */

:root {
  --bg:            #0f1113;
  --surface:       #16191d;
  --surface-alt:   #1c2025;
  --surface-high:  #232830;
  --border:        #2a2f37;
  --border-strong: #3a4048;
  --text:          #d6d9de;
  --text-muted:    #8a9099;
  --text-faint:    #5b6169;
  --accent:        #4fb3bf;         /* muted teal — engineering blue-green */
  --accent-hover:  #6ac5d0;
  --success:       #7cb87c;
  --warning:       #d6a24a;
  --error:         #e07070;
  --mono:          "JetBrains Mono", "SFMono-Regular", ui-monospace, Menlo, Consolas, monospace;
  --sans:          -apple-system, BlinkMacSystemFont, "Segoe UI", Inter, Arial, sans-serif;
}

* { box-sizing: border-box; }

html, body {
  margin: 0; padding: 0;
  height: 100vh; overflow: hidden;
  background: var(--bg);
  color: var(--text);
  font-family: var(--sans);
  font-size: 14px;
  line-height: 1.45;
}

/* ---- Topbar ---- */
.topbar {
  display: flex; align-items: center; justify-content: space-between;
  padding: 10px 18px;
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  height: 52px;
  flex-shrink: 0;
}
.brand { display: flex; align-items: center; gap: 12px; }
.brand-mark {
  font-size: 22px; color: var(--accent);
  line-height: 1;
}
.brand-text { line-height: 1.15; }
.brand-title { font-weight: 600; font-size: 14px; letter-spacing: 0.01em; }
.brand-sub { font-size: 11px; color: var(--text-faint); font-family: var(--mono); }
.topbar-actions { display: flex; align-items: center; gap: 10px; }
.chk { display: flex; align-items: center; gap: 6px; font-size: 12px; color: var(--text-muted); cursor: pointer; user-select: none; }
.chk input { accent-color: var(--accent); }
.btn {
  background: var(--accent);
  color: #0a1113;
  border: none;
  padding: 6px 14px;
  border-radius: 4px;
  font-size: 13px; font-weight: 600;
  cursor: pointer;
  font-family: inherit;
  transition: background 0.12s;
}
.btn:hover { background: var(--accent-hover); }
.btn.ghost {
  background: transparent;
  color: var(--text);
  border: 1px solid var(--border-strong);
  font-weight: 500;
}
.btn.ghost:hover { background: var(--surface-alt); border-color: var(--accent); color: var(--accent); }

/* ---- Workspace grid ---- */
.workspace {
  display: grid;
  grid-template-columns: 260px minmax(340px, 1fr) minmax(340px, 1.2fr);
  height: calc(100vh - 52px);
  overflow: hidden;
}

/* ---- Sidebar ---- */
.sidebar {
  background: var(--surface);
  border-right: 1px solid var(--border);
  overflow-y: auto;
  padding: 0;
}
.panel {
  padding: 14px 16px;
  border-bottom: 1px solid var(--border);
}
.panel-title {
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.09em;
  color: var(--text-muted);
  font-weight: 600;
  margin: 0 0 10px 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.panel-count {
  font-size: 10px;
  color: var(--text-faint);
  font-weight: 500;
  letter-spacing: 0;
  text-transform: none;
}
.filter-row {
  margin-bottom: 8px;
}
.filter-row input[type="search"] {
  width: 100%;
  background: var(--surface-alt);
  border: 1px solid var(--border);
  color: var(--text);
  font-family: var(--sans);
  font-size: 12px;
  padding: 5px 8px;
  border-radius: 3px;
  outline: none;
}
.filter-row input[type="search"]:focus {
  border-color: var(--accent);
}
.filter-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 4px;
  margin-bottom: 10px;
}
.tag {
  background: var(--surface-alt);
  border: 1px solid var(--border);
  color: var(--text-muted);
  font-size: 10px;
  padding: 3px 8px;
  border-radius: 3px;
  cursor: pointer;
  font-family: var(--sans);
  display: inline-flex;
  align-items: center;
  gap: 5px;
  transition: border-color 0.1s, color 0.1s;
}
.tag:hover { border-color: var(--border-strong); color: var(--text); }
.tag.active {
  border-color: var(--accent);
  color: var(--accent);
  background: rgba(79, 179, 191, 0.08);
}
.tag-count {
  font-size: 9px;
  color: var(--text-faint);
  background: var(--bg);
  padding: 1px 5px;
  border-radius: 8px;
  font-variant-numeric: tabular-nums;
}
.tag.active .tag-count { color: var(--accent); }

.example-list { list-style: none; padding: 0; margin: 0; }
.example-list li {
  padding: 7px 10px;
  border-radius: 4px;
  cursor: pointer;
  font-size: 12px;
  color: var(--text);
  margin-bottom: 2px;
  border: 1px solid transparent;
  transition: background 0.1s, border-color 0.1s;
}
.example-list li:hover { background: var(--surface-alt); border-color: var(--border); }
.example-list li.active { background: var(--surface-high); border-color: var(--accent); color: var(--accent); }
.example-title-row {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 6px;
}
.example-title {
  font-weight: 500;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.cat-badge {
  font-size: 9px;
  color: var(--text-faint);
  background: var(--surface-alt);
  padding: 1px 5px;
  border-radius: 2px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  flex-shrink: 0;
}
.cat-examples        { color: var(--accent); }
.cat-frames          { color: var(--warning); }
.cat-symbols         { color: var(--success); }
.cat-frame-guides    { color: #b48fd6; }
.cat-extended-symbols{ color: #d09570; }
.cat-my-drawings     { color: var(--accent-hover); background: rgba(79, 179, 191, 0.12); }
.example-desc {
  display: block;
  font-size: 11px;
  color: var(--text-faint);
  margin-top: 2px;
  line-height: 1.35;
}
.more-hint {
  cursor: default;
  color: var(--text-faint);
  font-size: 11px;
  padding: 8px 10px;
  font-style: italic;
}
.more-hint:hover { background: transparent; border-color: transparent; }

.ref-group { margin-bottom: 12px; }
.ref-heading {
  font-size: 11px;
  color: var(--text-muted);
  margin: 0 0 6px 0;
  font-weight: 600;
}
.ref-list { list-style: none; padding: 0; margin: 0; }
.ref-list li {
  padding: 5px 0;
  font-size: 11.5px;
  border-bottom: 1px dashed var(--border);
}
.ref-list li:last-child { border-bottom: none; }
.ref-sig { font-family: var(--mono); color: var(--accent); font-size: 11px; display: block; margin-bottom: 2px; }
.ref-desc { color: var(--text-muted); font-size: 11px; line-height: 1.35; }
.ref-footer { font-size: 11px; color: var(--text-faint); margin-top: 10px; line-height: 1.4; }

/* ---- Editor pane ---- */
.editor-pane {
  display: flex; flex-direction: column;
  border-right: 1px solid var(--border);
  min-width: 0;
}
.pane-header {
  padding: 8px 14px;
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  display: flex; align-items: baseline; gap: 12px;
  height: 34px;
  flex-shrink: 0;
}
.pane-title { font-size: 12px; font-weight: 600; color: var(--text); text-transform: uppercase; letter-spacing: 0.06em; }
.pane-hint { font-size: 11px; color: var(--text-faint); font-family: var(--mono); }

#editor {
  flex: 1;
  width: 100%;
  border: none;
  outline: none;
  padding: 16px 18px;
  background: var(--bg);
  color: var(--text);
  font-family: var(--mono);
  font-size: 13px;
  line-height: 1.65;
  resize: none;
  tab-size: 2;
}

.status-bar {
  display: flex; align-items: center; gap: 8px;
  padding: 6px 14px;
  background: var(--surface);
  border-top: 1px solid var(--border);
  font-family: var(--mono);
  font-size: 11.5px;
  color: var(--text-muted);
  min-height: 28px;
  flex-shrink: 0;
}
.status-dot {
  width: 8px; height: 8px; border-radius: 50%;
  background: var(--text-faint);
  flex-shrink: 0;
}
.status-bar.ok    .status-dot { background: var(--success); }
.status-bar.error .status-dot { background: var(--error); }
.status-bar.busy  .status-dot { background: var(--warning); animation: pulse 1s ease-in-out infinite; }
.status-bar.error #status-text { color: var(--error); }
@keyframes pulse { 0%,100% { opacity: 0.4; } 50% { opacity: 1; } }

/* ---- Preview pane ---- */
.preview-pane {
  display: flex; flex-direction: column;
  min-width: 0;
  background: var(--surface-alt);
}
.preview-canvas {
  flex: 1;
  padding: 20px;
  overflow: auto;
  display: flex;
  align-items: center;
  justify-content: center;
  background:
    linear-gradient(var(--surface-alt), var(--surface-alt)),
    repeating-linear-gradient(0deg, transparent 0 19px, rgba(255,255,255,0.02) 19px 20px),
    repeating-linear-gradient(90deg, transparent 0 19px, rgba(255,255,255,0.02) 19px 20px);
  background-blend-mode: normal, normal, normal;
}
.preview-canvas svg {
  background: #fafaf7;      /* paper */
  max-width: 100%;
  max-height: 100%;
  box-shadow: 0 4px 20px rgba(0,0,0,0.4), 0 0 0 1px var(--border);
  border-radius: 2px;
}
.preview-empty {
  color: var(--text-faint);
  font-size: 13px;
  font-style: italic;
}

/* ---- Scrollbars ---- */
::-webkit-scrollbar { width: 10px; height: 10px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: var(--border-strong); border-radius: 5px; }
::-webkit-scrollbar-thumb:hover { background: var(--text-faint); }

/* ---- Responsive ---- */
@media (max-width: 1100px) {
  .workspace { grid-template-columns: 220px 1fr; grid-template-rows: 55% 45%; }
  .preview-pane { grid-column: 2; }
  .editor-pane { grid-column: 2; grid-row: 1; }
  .sidebar { grid-column: 1; grid-row: 1 / span 2; }
}