:root {
  --bg-main: #fdfdfb;
  --bg-panel: #f4f4f2;
  --border: #cbcbc0;
  --accent: #2563eb;
  --text: #1a1a1a;
  --font-mono: 'Consolas', 'Monaco', 'Courier New', monospace;
  --surface: #ffffff;

  /* New properties to support flexible canvas rendering */
  --bg-node: #ffffff;
  --pipe-base: #888888;
  --arrow-base: #bbbbbb;
  --text-bg: rgba(255, 255, 255, 0.9);

  --icon-filter: invert(10%) sepia(10%) saturate(100%) hue-rotate(0deg) brightness(10%);
}

/* The Dark Mode Overrides */
[data-theme="dark"] {
  --bg-main: #121212;       /* Classic deep CAD onyx */
  --bg-panel: #1a1a1a;      /* Muted slate sidebar */
  --border: #2d2d2d;        /* Subtle dark grid borders */
  --accent: #3b82f6;        /* Slightly shifted neon blue for high-contrast visibility */
  --text: #e5e7eb;          /* Crispy light gray text */
  --surface: #666666;
  
  /* Canvas overrides */
  --bg-node: #1a1a1a;
  --pipe-base: #555555;
  --arrow-base: #444444;
  --text-bg: rgba(18, 18, 18, 0.85);

  --icon-filter: invert(90%) sepia(5%) saturate(100%) brightness(100%);
}

body { margin: 0; font-family: var(--font-mono); background: var(--bg-main); color: var(--text); overflow: hidden; }
#app { display: grid; grid-template-rows: 45px 1fr 25px; height: 100vh; }
header { background: var(--bg-panel); border-bottom: 1px solid var(--border); display: flex; align-items: center; padding: 0 20px; font-weight: bold; font-size: 14px; letter-spacing: 1px; }
#main { display: flex; flex: 1; position: relative; overflow: hidden; }
#canvas-container { flex: 1; position: relative; background-image: radial-gradient(var(--border) 1px, transparent 1px); background-size: 30px 30px; }
canvas { display: block; width: 100%; height: 100%; cursor: crosshair; }

#canvas-container { position: relative; }

#recenter-btn {
    position: absolute;
    bottom: 20px;
    right: 20px;
    width: 40px;
    height: 40px;
    border-radius: 5px;
    background-color: var(--surface, #ffffff);
    border: 1px solid var(--border, #cccccc);
    color: var(--text, #1a1a1a);
    font-size: 20px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    /*transition: all 0.1s ease;*/
    z-index: 10; /* Keeps it layered cleanly on top of mouse clicks */
}

#recenter-btn img { width: 20px; height: 20px; filter: invert(10%) sepia(10%) saturate(100%) hue-rotate(0deg) brightness(10%); /*transition: filter 0.2s ease;*/ }
#recenter-btn:hover img { filter: invert(100%) sepia(0%) saturate(0%) hue-rotate(0deg) brightness(100%); }
#recenter-btn:hover { background-color: var(--accent, #007acc); color: white; }

#tooltip {
  position: fixed;
  display: none;
  pointer-events: none;
  z-index: 1000;

  min-width: 120px;
  padding: 6px 8px;
  border-radius: 5px;

  /* Frosted Glass Layer */
  background: var(--text-bg);
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
  border: 1px solid var(--border);
  
  color: var(--text);
  font-family: var(--font-mono);
  line-height: 1.25;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
}

#tooltip .tt-header {
  display: flex;
  gap: 6px;
  margin-bottom: 4px;
  align-items: center;
  padding-bottom: 4px;
  font-weight: bold;
  text-transform: uppercase;
  letter-spacing: .05em;
  color: var(--accent);
  border-bottom: 1px solid var(--border);
}

#tooltip .tt-header img.icon { width: 12px; height: 12px; filter: var(--icon-filter); }

#tooltip .tt-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  margin: 2px 0;
}

#tooltip { font-size: 10px; }
#tooltip .tt-header { font-size: 12px; }

#tooltip .tt-badge { padding: 1px 5px; border-radius: 2px; font-size: 9px; }

#tooltip .badge-blue   { background: rgba(37, 99, 235, 0.12);  color: #1e40af; }
#tooltip .badge-green  { background: rgba(16, 185, 129, 0.12); color: #065f46; }
#tooltip .badge-orange { background: rgba(249, 115, 22, 0.12);  color: #9a3412; }
#tooltip .badge-gray   { background: rgba(0, 0, 0, 0.06);       color: #374151; }

[data-theme="dark"] #tooltip {
  box-shadow: 0 6px 16px rgba(0, 0, 0, 0.4);
}

[data-theme="dark"] #tooltip .badge-blue   { background: rgba(59, 130, 246, 0.2); color: #93c5fd; }
[data-theme="dark"] #tooltip .badge-green  { background: rgba(16, 185, 129, 0.2); color: #86efac; }
[data-theme="dark"] #tooltip .badge-orange { background: rgba(249, 115, 22, 0.2);  color: #fdba74; }
[data-theme="dark"] #tooltip .badge-gray   { background: rgba(255, 255, 255, 0.1); color: #d1d5db; }

#canvas-labels-layer {
  position: absolute;
  top: 0; left: 0; width: 100%; height: 100%;
  pointer-events: none;
  overflow: hidden;
}

/* Unified Label Base */
.html-node-demand,
.html-pipe-data {
  position: absolute;
  font-family: var(--font-mono);
  font-size: 12px;
  line-height: 1;
  color: var(--text);
  background: var(--text-bg);
  backdrop-filter: blur(4px);
  -webkit-backdrop-filter: blur(4px);
  border: 1px solid color-mix(in srgb, var(--border) 50%, transparent);
  border-radius: 3px;
  align-items: center;
  padding: 2px 6px;
  white-space: nowrap;
  user-select: none;
  transform: translate(-50%, -50%);
  will-change: transform;
}

/* Specific Modifiers */
.html-node-demand { font-weight: bold; letter-spacing: -0.02em; } 
.html-pipe-data .metric-lbl { opacity: 0.4; text-transform: uppercase; }
.html-pipe-data .data-sep { opacity: 0.25; }

.html-node-demand.node-supply { border-color: #10b98180; }
.html-node-demand.node-demand { border-color: #ef444480; }

#panel { width: 260px; background: var(--bg-panel); border-left: 1px solid var(--border); display: flex; flex-direction: column; }
.panel-header { padding: 15px; font-size: 10px; color: #888; border-bottom: 1px solid var(--border); text-transform: uppercase; }
.inspector-body { padding: 20px; flex: 1; overflow-y: auto; max-height: 100%; }

.prop-group { margin-bottom: 10px; }
.prop-group label { display: block; font-size: 10px; margin-bottom: 6px; font-weight: bold; color: var(--text); }
input { width: 100%; padding: 10px; border: 1px solid var(--border); color: var(--text); background: var(--text-bg); font-family: var(--font-mono); font-size: 12px; outline: none; box-sizing: border-box; }
input:focus { border-color: var(--accent); }

.empty-state { color: #aaa; text-align: center; padding: 40px 0; font-style: italic; font-size: 11px; }
.btn-danger { width: 100%; margin-top: 10px; padding: 10px; background: transparent; border: 1px solid #dc2626; color: #dc2626; cursor: pointer; font-family: var(--font-mono); font-size: 10px; }
.btn-danger:hover { background: #fee2e2; }

button { font-family: var(--font-mono); }

#snap-toggle-btn {
  background: transparent; border: none; border-left: 1px solid var(--border);
  height: 100%; align-self: stretch; padding: 0 15px; cursor: pointer;
  display: flex; align-items: center; justify-content: center;
  transition: background 0.1s ease; box-sizing: border-box; box-shadow: none;
}
#snap-toggle-btn:hover { background: color-mix(in srgb, var(--text) 5%, transparent); }
#snap-toggle-btn.snap-active {
  background: color-mix(in srgb, var(--text) 12%, transparent);
  box-shadow: inset 0 -2px 0 0 var(--accent);
}
#snap-toggle-btn img { width: 14px; height: 14px; display: block; opacity: 0.75; }

footer { background: var(--bg-panel); border-top: 1px solid var(--border); font-size: 9px; padding: 0 15px; display: flex; align-items: center; color: #aaa; }
.footer-metric { font-family: var(--font-mono); letter-spacing: 0.05em; }

/* Pan Icon */
.panning-active { cursor: grab !important; }

/* Mobile Blocker Overlay */
#mobile-blocker {
  display: none; /* Hidden by default on desktop */
  position: fixed; top: 0; left: 0; width: 100vw; height: 100vh; background: var(--bg-main); z-index: 9999; /* Sit on top of everything */
  justify-content: center; align-items: center; padding: 30px; box-sizing: border-box;
}

.blocker-content { text-align: center; max-width: 320px; border: 1px solid var(--border); background: var(--bg-panel); padding: 30px 20px; border-radius: 4px; box-shadow: 0 4px 12px rgba(0,0,0,0.05); }
.blocker-content h2 { margin: 0 0 5px 0; color: var(--accent); font-size: 18px; letter-spacing: 1px; }
.blocker-content p { margin: 0; font-size: 12px; font-weight: bold; }

/* Media Query: Triggered when screen width is under 768px */
@media (max-width: 767px) {
  #mobile-blocker {
    display: flex; /* Show overlay on mobile devices */
  }
  #app {
    display: none; /* Hide the main app layout completely to save performance */
  }
}