/* ═══════════════════════════════════════════════════════════
   canvas.css — Knowledge Canvas main stylesheet
   Dark theme (default) + Light theme via [data-theme="light"]
   ═══════════════════════════════════════════════════════════ */

/* ─── CSS Custom Properties: Dark Theme (Default) ─── */
:root {
  --bg: #0a0a0f;
  --surface: #131320;
  --surface-hover: #1a1a2e;
  --border: #252540;
  --border-active: #4a4a7a;
  --text: #d4d4e8;
  --text-dim: #7a7a9a;
  --text-bright: #eeeefc;
  --accent: #6c5ce7;
  --accent-dim: rgba(108, 92, 231, 0.15);
  --accent-glow: rgba(108, 92, 231, 0.3);
  --link: #74b9ff;
  --link-hover: #a29bfe;
  --card-shadow: 0 8px 32px rgba(0,0,0,0.5), 0 2px 8px rgba(0,0,0,0.3);
  --card-shadow-active: 0 16px 48px rgba(0,0,0,0.6), 0 4px 16px rgba(108,92,231,0.2);
  --radius: 8px;
  --header-h: 38px;
  --sidebar-width: 280px;
  --grid-dot-color: rgba(100,100,160,0.08);
  --overlay-bg: rgba(13,13,20,0.85);
  --overlay-bg-strong: rgba(13,13,20,0.9);
  --overlay-bg-strongest: rgba(13,13,20,0.95);
  --card-header-bg: rgba(255,255,255,0.02);
  --card-btn-hover-bg: rgba(255,255,255,0.06);
}

/* ─── CSS Custom Properties: Light Theme ─── */
[data-theme="light"] {
  --bg: #f5f5f0;
  --surface: #ffffff;
  --surface-hover: #f0f0eb;
  --border: #e0ddd5;
  --border-active: #b8b5ad;
  --text: #2a2a3a;
  --text-dim: #6b6b7b;
  --text-bright: #1a1a2a;
  --accent: #6c5ce7;
  --accent-dim: rgba(108, 92, 231, 0.1);
  --accent-glow: rgba(108, 92, 231, 0.15);
  --link: #4a6fa5;
  --link-hover: #6c5ce7;
  --card-shadow: 0 2px 12px rgba(0,0,0,0.08), 0 1px 4px rgba(0,0,0,0.04);
  --card-shadow-active: 0 4px 20px rgba(0,0,0,0.12), 0 2px 8px rgba(108,92,231,0.1);
  --grid-dot-color: rgba(100,100,120,0.08);
  --overlay-bg: rgba(255,255,255,0.9);
  --overlay-bg-strong: rgba(255,255,255,0.9);
  --overlay-bg-strongest: rgba(255,255,255,0.95);
  --card-header-bg: rgba(0,0,0,0.02);
  --card-btn-hover-bg: rgba(0,0,0,0.06);
}

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

/* ─── Body ─── */
body {
  background: var(--bg);
  color: var(--text);
  font-family: 'Source Serif 4', Georgia, serif;
  overflow: hidden;
  width: 100vw;
  height: 100vh;
  cursor: default;
  user-select: none;
  transition: padding-left 0.3s ease;
}

/* Sidebar open state — shifts content right */
body.sidebar-open {
  padding-left: var(--sidebar-width);
}

/* ─── View System ─── */
.view {
  display: none;
  width: 100%;
  height: 100%;
}
.view.active {
  display: block;
}

/* ─── Home View ─── */
#home-view {
  overflow-y: auto;
  cursor: auto;
  user-select: text;
}
.home-container {
  max-width: none;
  margin: 0;
  padding: 60px 40px 120px 48px;
  overflow: visible;
}
.home-content {
  font-size: 17px;
  line-height: 1.7;
  color: var(--text);
}

/* Canvas view overrides */
#canvas-view { cursor: grab; position: relative; overflow: hidden; }
#canvas-view:active { cursor: grabbing; }

/* ─── Infinite Canvas ─── */
#canvas-viewport {
  width: 100%;
  height: 100%;
  position: relative;
  overflow: hidden;
}

#canvas-world {
  position: absolute;
  transform-origin: 0 0;
  will-change: transform;
}

/* Grid background */
#canvas-viewport::before {
  content: '';
  position: absolute;
  inset: 0;
  background-image:
    radial-gradient(circle at 1px 1px, var(--grid-dot-color) 1px, transparent 0);
  background-size: 40px 40px;
  pointer-events: none;
  z-index: 0;
}

/* ─── Connection Lines (SVG layer) ─── */
#connections-layer {
  position: absolute;
  top: 0; left: 0;
  width: 1px; height: 1px;
  overflow: visible;
  pointer-events: none;
  z-index: 1;
}
#connections-layer line {
  stroke: var(--accent);
  stroke-width: 1.5;
  opacity: 0.25;
  stroke-dasharray: 6 4;
}

/* ─── Cards ─── */
.card {
  position: absolute;
  width: 480px;
  max-height: 600px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--card-shadow);
  display: flex;
  flex-direction: column;
  z-index: 10;
  transition: box-shadow 0.2s, border-color 0.2s;
  animation: cardIn 0.3s cubic-bezier(0.16, 1, 0.3, 1) both;
  overflow: hidden;
}

/* Card states */
.card[data-state="full"] .card-abstract { display: none; }
.card[data-state="mini"] .card-body { display: none; }
.card[data-state="mini"] .card-abstract { display: block; }
.card[data-state="collapsed"] .card-body { display: none; }
.card[data-state="collapsed"] .card-abstract { display: none; }
.card[data-state="collapsed"] .card-header { border-bottom: none; border-radius: var(--radius); }

@keyframes cardIn {
  from { opacity: 0; transform: scale(0.92) translateY(8px); }
  to { opacity: 1; transform: scale(1) translateY(0); }
}

.card:hover { border-color: var(--border-active); }
.card.active {
  border-color: var(--accent);
  box-shadow: var(--card-shadow-active);
  z-index: 100;
}

/* ─── Card Header ─── */
.card-header {
  height: var(--header-h);
  min-height: var(--header-h);
  display: flex;
  align-items: center;
  padding: 0 10px;
  background: var(--card-header-bg);
  border-bottom: 1px solid var(--border);
  border-radius: var(--radius) var(--radius) 0 0;
  cursor: grab;
  gap: 8px;
}
.card-header:active { cursor: grabbing; }

/* ─── Card Dot (state indicator) ─── */
.card-dot {
  width: 8px; height: 8px;
  border-radius: 50%;
  background: var(--accent);
  opacity: 0.6;
  flex-shrink: 0;
}
.card[data-state="mini"] .card-dot { background: #ffa502; }
.card[data-state="collapsed"] .card-dot { background: var(--text-dim); }

/* ─── Card Title ─── */
.card-title {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 12px;
  font-weight: 500;
  color: var(--text-dim);
  letter-spacing: 0.04em;
  text-transform: uppercase;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  flex: 1;
  text-decoration: none;
  cursor: grab;
  transition: color 0.15s;
}
.card-title:hover {
  color: var(--link);
  cursor: pointer;
}

/* ─── Card Buttons ─── */
.card-btn {
  width: 22px; height: 22px;
  border: none; background: transparent;
  color: var(--text-dim);
  font-size: 14px; cursor: pointer;
  border-radius: 4px;
  display: flex; align-items: center; justify-content: center;
  flex-shrink: 0;
  transition: background 0.15s, color 0.15s;
  font-family: 'IBM Plex Mono', monospace;
  line-height: 1;
}
.card-btn:hover { background: var(--card-btn-hover-bg); color: var(--text-bright); }
.card-btn.close-btn:hover { background: rgba(255,80,80,0.15); color: #ff6b6b; }
.card-btn-state.active-state { background: var(--accent-dim); color: var(--accent); }

/* ─── Card Abstract (mini state) ─── */
.card-abstract {
  display: none;
  padding: 12px 16px;
  font-size: 13px;
  line-height: 1.6;
  color: var(--text-dim);
  cursor: auto;
  user-select: text;
}
.card-abstract .abstract-text {
  display: -webkit-box;
  -webkit-line-clamp: 5;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
.card-abstract .abstract-tags {
  margin-top: 8px;
  display: flex; flex-wrap: wrap; gap: 4px;
}

/* ─── Resize Handles ─── */
.resize-handle { position: absolute; z-index: 5; }
.resize-handle.rh-right { top: var(--header-h); bottom: 0; right: -3px; width: 6px; cursor: ew-resize; }
.resize-handle.rh-bottom { left: 0; right: 0; bottom: -3px; height: 6px; cursor: ns-resize; }
.resize-handle.rh-corner { right: -4px; bottom: -4px; width: 14px; height: 14px; cursor: nwse-resize; }
.resize-handle.rh-left { top: var(--header-h); bottom: 0; left: -3px; width: 6px; cursor: ew-resize; }
.resize-handle.rh-corner::after {
  content: ''; position: absolute; right: 4px; bottom: 4px;
  width: 8px; height: 8px;
  border-right: 2px solid var(--border-active);
  border-bottom: 2px solid var(--border-active);
  opacity: 0; transition: opacity 0.2s;
}
.card:hover .resize-handle.rh-corner::after { opacity: 1; }

/* ─── Card Body ─── */
.card-body {
  padding: 20px 22px;
  overflow-y: auto;
  flex: 1;
  font-size: 15px;
  line-height: 1.7;
  color: var(--text);
  cursor: auto;
  user-select: text;
}
/* Vertical scrollbar — slim, hover-reveal */
.card-body::-webkit-scrollbar { width: 4px; }
.card-body::-webkit-scrollbar-track { background: transparent; }
.card-body::-webkit-scrollbar-thumb { background: transparent; border-radius: 2px; transition: background 0.2s; }
.card:hover .card-body::-webkit-scrollbar-thumb { background: var(--border); }
.card:hover .card-body::-webkit-scrollbar-thumb:hover { background: var(--border-active); }

/* Horizontal scrollbar — very slim, hover-reveal */
.card-body::-webkit-scrollbar:horizontal { height: 5px; }
.card-body { overflow-x: auto; }
.card-body::-webkit-scrollbar-thumb:horizontal { background: transparent; border-radius: 2px; }
.card:hover .card-body::-webkit-scrollbar-thumb:horizontal { background: var(--border); }

.card-body h2 {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--accent);
  margin: 20px 0 8px;
}
.card-body h2:first-child { margin-top: 0; }

.card-body p { margin-bottom: 12px; }

.card-body a.wiki-link {
  color: var(--link);
  text-decoration: none;
  border-bottom: 1px dotted var(--link);
  cursor: pointer;
  transition: color 0.15s, border-color 0.15s;
}
.card-body a.wiki-link:hover {
  color: var(--link-hover);
  border-bottom-color: var(--link-hover);
}

.card-body .tag {
  display: inline-block;
  font-family: 'IBM Plex Mono', monospace;
  font-size: 10px;
  padding: 2px 8px;
  border-radius: 3px;
  background: var(--accent-dim);
  color: var(--accent);
  margin: 2px 4px 2px 0;
  letter-spacing: 0.03em;
}

.card-body blockquote {
  border-left: 2px solid var(--accent);
  padding-left: 14px;
  margin: 12px 0;
  color: var(--text-dim);
  font-style: italic;
}

.card-body ul, .card-body ol {
  padding-left: 20px;
  margin-bottom: 12px;
}
.card-body li { margin-bottom: 4px; }

/* ─── Minimap ─── */
#minimap {
  position: fixed;
  bottom: 16px;
  right: 16px;
  width: 200px;
  height: 140px;
  background: var(--overlay-bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  z-index: 9999;
  overflow: hidden;
  backdrop-filter: blur(8px);
}
#minimap-canvas {
  width: 100%;
  height: 100%;
}

/* ─── Toolbar ─── */
#toolbar {
  position: fixed;
  top: 16px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  align-items: center;
  gap: 2px;
  background: var(--overlay-bg-strong);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 4px;
  z-index: 9999;
  backdrop-filter: blur(12px);
  font-family: 'IBM Plex Mono', monospace;
}
.tb-btn {
  height: 32px;
  padding: 0 14px;
  border: none;
  background: transparent;
  color: var(--text-dim);
  font-family: inherit;
  font-size: 12px;
  cursor: pointer;
  border-radius: 5px;
  transition: background 0.15s, color 0.15s;
  white-space: nowrap;
}
.tb-btn:hover { background: var(--surface-hover); color: var(--text-bright); }
.tb-btn.active { background: var(--accent-dim); color: var(--accent); }
.tb-sep { width: 1px; height: 20px; background: var(--border); margin: 0 4px; }
#zoom-display {
  font-size: 11px;
  color: var(--text-dim);
  padding: 0 10px;
  min-width: 48px;
  text-align: center;
}

/* ─── Theme Toggle Button ─── */
.tb-btn.theme-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 15px;
  padding: 0 10px;
  min-width: 32px;
}
.tb-btn.theme-toggle:hover {
  background: var(--surface-hover);
  color: var(--text-bright);
}

/* ─── Search ─── */
#search-bar {
  position: fixed;
  top: 16px;
  right: 16px;
  z-index: 9999;
}
#search-input {
  width: 220px;
  height: 34px;
  background: var(--overlay-bg-strong);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 0 12px;
  color: var(--text);
  font-family: 'IBM Plex Mono', monospace;
  font-size: 12px;
  outline: none;
  backdrop-filter: blur(12px);
  transition: border-color 0.2s, width 0.3s;
}
#search-input::placeholder { color: var(--text-dim); }
#search-input:focus { border-color: var(--accent); width: 300px; }
#search-results {
  margin-top: 4px;
  background: var(--overlay-bg-strongest);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  max-height: 300px;
  overflow-y: auto;
  display: none;
}
#search-results.visible { display: block; }
.search-item {
  padding: 8px 12px;
  font-family: 'IBM Plex Mono', monospace;
  font-size: 12px;
  color: var(--text-dim);
  cursor: pointer;
  transition: background 0.1s;
}
.search-item:hover { background: var(--surface-hover); color: var(--text); }
.search-item .search-category {
  font-size: 9px;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--accent);
  margin-left: 6px;
}

/* ─── Help Hint ─── */
#help-hint {
  position: fixed;
  bottom: 16px;
  left: 16px;
  font-family: 'IBM Plex Mono', monospace;
  font-size: 11px;
  color: var(--text-dim);
  z-index: 9999;
  opacity: 0.5;
  line-height: 1.7;
}