.column-calc-tool *, .column-calc-tool *::before, .column-calc-tool *::after { margin: 0; padding: 0; box-sizing: border-box; }
:root {
  --bg: #f8f9fa;
  --card: #ffffff;
  --border: #dee2e6;
  --text: #212529;
  --text-dim: #6c757d;
  --accent: #2563eb;
  --accent-light: #dbeafe;
  --green: #16a34a;
  --green-bg: #dcfce7;
  --yellow: #ca8a04;
  --yellow-bg: #fef9c3;
  --red: #dc2626;
  --red-bg: #fee2e2;
  --orange: #ea580c;
  --orange-bg: #ffedd5;
  --input-bg: #f1f5f9;
  --shadow: 0 1px 3px rgba(0,0,0,0.1);
}
.column-calc-tool {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', system-ui, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  padding: 0;
  box-sizing: border-box;
}
.column-calc-tool h1 { font-size: 24px; font-weight: 700; margin-bottom: 4px; color: var(--text); }
.column-calc-tool .subtitle { color: var(--text-dim); font-size: 14px; margin-bottom: 24px; }

.column-calc-tool .layout { display: block; max-width: 100%; overflow: hidden; }
.column-calc-tool .inputs-panel, .column-calc-tool .results-panel { max-width: 100%; }
.column-calc-tool .card { max-width: 100%; overflow: hidden; }
.column-calc-tool canvas { max-width: 100%; }

/* Cards */
.column-calc-tool .card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 20px;
  box-shadow: var(--shadow);
  margin-bottom: 16px;
}
.column-calc-tool .card-title {
  font-size: 14px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  color: var(--text-dim);
  margin-bottom: 16px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--border);
}

/* Mobile touch improvements */
.column-calc-tool button, .column-calc-tool .clickable {
  -webkit-tap-highlight-color: transparent;
  touch-action: manipulation;
  min-height: 44px;
  min-width: 44px;
}

/* Inputs */
.column-calc-tool .input-group { margin-bottom: 14px; }
.column-calc-tool .input-group label {
  display: block;
  font-size: 13px;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 4px;
}
.column-calc-tool .input-group .hint {
  font-size: 11px;
  color: var(--text-dim);
  margin-bottom: 4px;
}
.column-calc-tool .input-group input, .column-calc-tool .input-group select {
  width: 100%;
  padding: 8px 12px;
  border: 1px solid var(--border);
  border-radius: 6px;
  font-size: 14px;
  background: var(--input-bg);
  color: var(--text);
}
.column-calc-tool .input-group input:focus, .column-calc-tool .input-group select:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-light);
}
.column-calc-tool .input-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
}

/* End condition selector */
.column-calc-tool .end-conditions {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 8px;
  margin-bottom: 14px;
}
.column-calc-tool .end-btn {
  background: var(--input-bg);
  border: 2px solid var(--border);
  border-radius: 8px;
  padding: 10px 4px 8px;
  cursor: pointer;
  text-align: center;
  transition: all 0.2s;
  font-size: 11px;
  font-weight: 600;
  color: var(--text-dim);
  -webkit-tap-highlight-color: transparent;
  touch-action: manipulation;
  min-height: 80px;
}
.column-calc-tool .end-btn:hover { border-color: var(--accent); color: var(--accent); }
.column-calc-tool .end-btn.active {
  border-color: var(--accent);
  background: var(--accent-light);
  color: var(--accent);
}
.column-calc-tool .end-btn svg { display: block; margin: 0 auto 6px; }
.column-calc-tool .end-btn .k-val { font-size: 13px; font-weight: 700; color: var(--accent); margin-top: 2px; }

/* Cross section selector */
.column-calc-tool .section-tabs {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-bottom: 14px;
}
.column-calc-tool .section-tab {
  padding: 8px 12px;
  border: 1px solid var(--border);
  border-radius: 6px;
  font-size: 12px;
  font-weight: 600;
  cursor: pointer;
  background: var(--input-bg);
  color: var(--text-dim);
  transition: all 0.15s;
  -webkit-tap-highlight-color: transparent;
  touch-action: manipulation;
  min-height: 44px;
}
.column-calc-tool .section-tab:hover { border-color: var(--accent); color: var(--accent); }
.column-calc-tool .section-tab.active { background: var(--accent); color: white; border-color: var(--accent); }

/* Results */
.column-calc-tool .result-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
  margin-bottom: 16px;
}
.column-calc-tool .result-box {
  background: var(--input-bg);
  border-radius: 8px;
  padding: 14px;
  text-align: center;
}
.column-calc-tool .result-box.full { grid-column: 1 / -1; }
.column-calc-tool .result-label {
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.3px;
  color: var(--text-dim);
  margin-bottom: 4px;
}
.column-calc-tool .result-value {
  font-size: 22px;
  font-weight: 700;
  color: var(--text);
}
.column-calc-tool .result-unit {
  font-size: 13px;
  font-weight: 400;
  color: var(--text-dim);
}
.column-calc-tool .result-sub {
  font-size: 11px;
  color: var(--text-dim);
  margin-top: 2px;
}

/* Status badge */
.column-calc-tool .status-badge {
  display: inline-block;
  padding: 4px 12px;
  border-radius: 20px;
  font-size: 12px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}
.column-calc-tool .status-safe { background: var(--green-bg); color: var(--green); }
.column-calc-tool .status-warn { background: var(--yellow-bg); color: var(--yellow); }
.column-calc-tool .status-danger { background: var(--red-bg); color: var(--red); }
.column-calc-tool .status-info { background: var(--accent-light); color: var(--accent); }

/* Demand/Capacity bar */
.column-calc-tool .dc-bar-container {
  background: var(--input-bg);
  border-radius: 8px;
  padding: 16px;
  margin-bottom: 16px;
}
.column-calc-tool .dc-bar-track {
  width: 100%;
  height: 24px;
  background: linear-gradient(90deg, #dcfce7 0%, #dcfce7 60%, #fef9c3 70%, #ffedd5 85%, #fee2e2 100%);
  border-radius: 12px;
  position: relative;
  overflow: visible;
  margin: 8px 0;
}
.column-calc-tool .dc-bar-marker {
  position: absolute;
  top: -4px;
  width: 4px;
  height: 32px;
  background: var(--text);
  border-radius: 2px;
  transition: left 0.3s ease;
}
.column-calc-tool .dc-bar-labels {
  display: flex;
  justify-content: space-between;
  font-size: 11px;
  color: var(--text-dim);
}
.column-calc-tool .dc-bar-limit {
  position: absolute;
  top: 0;
  height: 24px;
  border-left: 2px dashed var(--red);
}

/* Canvas responsive sizing */
.column-calc-tool .diagram-container {
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 300px;
}
.column-calc-tool canvas {
  max-width: 100%;
  height: auto;
}

/* Unit toggle */
.column-calc-tool .unit-toggle {
  display: flex;
  border: 1px solid var(--border);
  border-radius: 6px;
  overflow: hidden;
  margin-bottom: 16px;
}
.column-calc-tool .unit-toggle button {
  flex: 1;
  padding: 8px;
  border: none;
  font-size: 12px;
  font-weight: 600;
  cursor: pointer;
  background: var(--input-bg);
  color: var(--text-dim);
  transition: all 0.15s;
  -webkit-tap-highlight-color: transparent;
  touch-action: manipulation;
  min-height: 44px;
}
.column-calc-tool .unit-toggle button.active {
  background: var(--accent);
  color: white;
}

/* Design method toggle */
.column-calc-tool .design-toggle {
  display: flex;
  border: 1px solid var(--border);
  border-radius: 6px;
  overflow: hidden;
  margin-bottom: 16px;
}
.column-calc-tool .design-toggle button {
  flex: 1;
  padding: 8px;
  border: none;
  font-size: 12px;
  font-weight: 600;
  cursor: pointer;
  background: var(--input-bg);
  color: var(--text-dim);
  transition: all 0.15s;
  -webkit-tap-highlight-color: transparent;
  touch-action: manipulation;
  min-height: 44px;
}
.column-calc-tool .design-toggle button.active {
  background: var(--accent);
  color: white;
}

/* Material presets */
.column-calc-tool .material-presets {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-bottom: 10px;
}
.column-calc-tool .mat-btn {
  padding: 6px 12px;
  border: 1px solid var(--border);
  border-radius: 4px;
  font-size: 11px;
  cursor: pointer;
  background: var(--input-bg);
  color: var(--text-dim);
  font-weight: 600;
  transition: all 0.15s;
  -webkit-tap-highlight-color: transparent;
  touch-action: manipulation;
  min-height: 44px;
}
.column-calc-tool .mat-btn:hover { border-color: var(--accent); color: var(--accent); }
.column-calc-tool .mat-btn.active { background: var(--accent); color: white; border-color: var(--accent); }

/* Collapsible section */
.column-calc-tool .collapsible {
  border: 1px solid var(--border);
  border-radius: 8px;
  overflow: hidden;
  margin-bottom: 16px;
}
.column-calc-tool .collapsible-header {
  background: var(--input-bg);
  padding: 12px 16px;
  cursor: pointer;
  font-weight: 600;
  font-size: 14px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  -webkit-tap-highlight-color: transparent;
  touch-action: manipulation;
  min-height: 44px;
}
.column-calc-tool .collapsible-header:hover { background: #e2e8f0; }
.column-calc-tool .collapsible-content {
  padding: 16px;
  background: var(--card);
  display: none;
}
.column-calc-tool .collapsible.active .collapsible-content {
  display: block;
}
.column-calc-tool .collapsible-arrow {
  transition: transform 0.2s;
}
.column-calc-tool .collapsible.active .collapsible-arrow {
  transform: rotate(180deg);
}

/* Applied load section */
.column-calc-tool .load-input-row {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 10px;
}
.column-calc-tool .load-input-row input {
  flex: 1;
  padding: 8px 12px;
  border: 1px solid var(--border);
  border-radius: 6px;
  font-size: 14px;
  background: var(--input-bg);
}
.column-calc-tool .load-input-row .unit-label {
  font-size: 12px;
  color: var(--text-dim);
  font-weight: 600;
  min-width: 40px;
}

/* Table for section properties */
.column-calc-tool .props-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 13px;
}
.column-calc-tool .props-table td {
  padding: 6px 8px;
  border-bottom: 1px solid var(--border);
}
.column-calc-tool .props-table td:first-child {
  color: var(--text-dim);
  font-weight: 600;
  width: 55%;
}
.column-calc-tool .props-table td:last-child {
  text-align: right;
  font-weight: 600;
  font-variant-numeric: tabular-nums;
}

/* Safety factor input */
.column-calc-tool .sf-row {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-top: 10px;
}
.column-calc-tool .sf-row label { font-size: 13px; font-weight: 600; white-space: nowrap; }
.column-calc-tool .sf-row input {
  width: 70px;
  padding: 6px 10px;
  border: 1px solid var(--border);
  border-radius: 6px;
  font-size: 14px;
  background: var(--input-bg);
  text-align: center;
}

/* Warnings */
.column-calc-tool .warning-box {
  padding: 10px 14px;
  border-radius: 8px;
  font-size: 13px;
  margin-bottom: 12px;
  display: none;
}
.column-calc-tool .warning-box.show { display: block; }
.column-calc-tool .warning-box.warn { background: var(--yellow-bg); color: var(--yellow); border: 1px solid #fde68a; }
.column-calc-tool .warning-box.danger { background: var(--red-bg); color: var(--red); border: 1px solid #fca5a5; }
.column-calc-tool .warning-box.info { background: var(--accent-light); color: var(--accent); border: 1px solid #93c5fd; }