/* ============================================================
   案件线索墙 — Board Canvas Styles
   东北工业怀旧 · 软木板画布
   ============================================================ */

/* ── 画布容器 ── */
.board-container {
  position: relative;
  flex: 1;
  overflow: hidden;
  background:
    /* 软木板纹理 — 用多层渐变模拟 */
    repeating-conic-gradient(rgba(139,90,43,0.03) 0% 25%, transparent 0% 50%) 0 0 / 20px 20px,
    repeating-conic-gradient(rgba(139,90,43,0.02) 0% 25%, transparent 0% 50%) 10px 10px / 20px 20px,
    /* 铁锈斑驳 */
    radial-gradient(ellipse at 15% 20%, rgba(139,69,19,0.08), transparent 50%),
    radial-gradient(ellipse at 85% 75%, rgba(139,69,19,0.06), transparent 40%),
    radial-gradient(ellipse at 50% 50%, rgba(107,80,50,0.04), transparent 60%),
    /* 底色 */
    linear-gradient(135deg, #d4c4a0 0%, #c8b48e 50%, #baa67a 100%);
  border-left: 2px solid rgba(139, 90, 43, 0.3);
}

/* ── 可拖拽画布 ── */
.board-canvas {
  position: absolute;
  top: 0;
  left: 0;
  width: 4000px;
  height: 3000px;
  transform-origin: 0 0;
  transition: transform var(--duration-normal) var(--ease-out);
  cursor: grab;
}

.board-canvas:active {
  cursor: grabbing;
}

.board-canvas.dragging-card {
  cursor: default;
}

/* ── SVG 连线层 ── */
.board-svg {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  z-index: 1;
}

.board-svg line,
.board-svg path {
  pointer-events: stroke;
  cursor: pointer;
}

/* ── 画布缩放控件 ── */
.board-zoom {
  position: absolute;
  bottom: var(--space-4);
  right: var(--space-4);
  display: flex;
  flex-direction: column;
  gap: var(--space-1);
  z-index: 10;
}

.board-zoom button {
  width: 36px;
  height: 36px;
  border: 1px solid rgba(139, 90, 43, 0.4);
  border-radius: var(--radius-sm);
  background: var(--paper-aged);
  color: var(--text-soft);
  font-size: var(--text-lg);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all var(--duration-fast) var(--ease-out);
}

.board-zoom button:hover {
  background: var(--paper-strong);
  color: var(--accent);
  border-color: var(--accent);
}

/* ── 画布水印/标识 ── */
.board-watermark {
  position: absolute;
  bottom: var(--space-8);
  left: 50%;
  transform: translateX(-50%);
  font-family: var(--font-display);
  font-size: 3rem;
  color: rgba(139, 90, 43, 0.08);
  white-space: nowrap;
  pointer-events: none;
  z-index: 0;
  letter-spacing: 0.2em;
}

/* ── 网格辅助线（开发调试用，默认隐藏）── */
.board-grid {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  opacity: 0;
  z-index: 0;
  background-image:
    linear-gradient(rgba(139,90,43,0.1) 1px, transparent 1px),
    linear-gradient(90deg, rgba(139,90,43,0.1) 1px, transparent 1px);
  background-size: 100px 100px;
}

.board-grid.visible {
  opacity: 1;
}