/* =====================================================================
   REAL NUMBERS — Class 10 Maths Notes
   Static SVG diagram styles, number system cards, proof boxes,
   and layout styling. Base styles (.notes-page-wrap, .notes-toc, etc.)
   inherit from /css/notes-content.css.
   ===================================================================== */

/* Diagram & Visual Wrappers */
.rn-diagram-wrapper {
  display: flex;
  flex-direction: column;
  align-items: center;
  margin: 22px auto;
  max-width: 520px;
}

.rn-diagram-wrapper svg {
  display: block;
  width: 100%;
  height: auto;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  user-select: none;
}

.rn-diagram-caption {
  margin-top: 8px;
  font-size: 13px;
  color: #64748b;
  text-align: center;
  line-height: 1.5;
}

/* Proof & Derivation Container Box */
.proof-box {
  background-color: #f8fafc;
  border: 1px solid #e2e8f0;
  border-left: 4px solid #2563eb;
  border-radius: 6px;
  padding: 16px 20px;
  margin: 18px 0;
  font-size: 14.5px;
  line-height: 1.7;
  color: #334155;
}

.proof-header {
  font-size: 12px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: #2563eb;
  margin-bottom: 8px;
}

.proof-step {
  margin-bottom: 8px;
}

.proof-step strong {
  color: #0f172a;
}

/* Number Set Grid */
.number-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 16px;
  margin: 20px 0;
}

.number-card {
  background: #ffffff;
  border: 1px solid #e2e8f0;
  border-radius: 8px;
  padding: 18px 20px;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.04);
}

.number-card h4 {
  margin: 0 0 8px 0;
  font-size: 15.5px;
  font-weight: 700;
  color: #0f172a;
}

.number-card p {
  margin: 0 0 10px 0;
  font-size: 13.5px;
  color: #475569;
  line-height: 1.55;
}

.number-badge {
  display: inline-block;
  font-size: 11.5px;
  font-weight: 700;
  text-transform: uppercase;
  color: #2563eb;
  background: #eff6ff;
  border: 1px solid #bfdbfe;
  border-radius: 4px;
  padding: 2px 7px;
  margin-bottom: 8px;
}

/* Factor Tree & SVG Elements */
.rn-tree-node {
  fill: #ffffff;
  stroke: #0f172a;
  stroke-width: 2;
}

.rn-tree-leaf {
  fill: rgba(37, 99, 235, 0.12);
  stroke: #2563eb;
  stroke-width: 2;
}

.rn-tree-branch {
  stroke: #64748b;
  stroke-width: 1.8;
}

.rn-venn-real {
  fill: rgba(248, 250, 252, 0.9);
  stroke: #0f172a;
  stroke-width: 2.2;
}

.rn-venn-rational {
  fill: rgba(37, 99, 235, 0.08);
  stroke: #2563eb;
  stroke-width: 1.8;
}

.rn-venn-irrational {
  fill: rgba(220, 38, 38, 0.08);
  stroke: #dc2626;
  stroke-width: 1.8;
}

.rn-venn-integers {
  fill: rgba(16, 185, 129, 0.1);
  stroke: #059669;
  stroke-width: 1.6;
}

.rn-venn-whole {
  fill: rgba(245, 158, 11, 0.12);
  stroke: #d97706;
  stroke-width: 1.6;
}

.rn-venn-natural {
  fill: rgba(99, 102, 241, 0.15);
  stroke: #4f46e5;
  stroke-width: 1.6;
}

/* SVG Typography */
.rn-text {
  font-size: 13px;
  font-weight: 600;
  fill: #1e293b;
}

.rn-text-accent {
  font-size: 13px;
  font-weight: 700;
  fill: #2563eb;
}

.rn-text-red {
  font-size: 13px;
  font-weight: 700;
  fill: #dc2626;
}

.rn-text-muted {
  font-size: 12px;
  font-weight: 500;
  fill: #64748b;
}