/* ==========================================================================
   CALCULATOR WORKSPACE, KEYPAD & VISUAL BREAKDOWNS
   ========================================================================== */

/* --------------------------------------------------------------------------
   Workspace Layout (Dual Column)
   -------------------------------------------------------------------------- */
.workspace-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 1.5rem;
  margin-bottom: 1.5rem;
  width: 100%;
}

.workspace-title-area {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.workspace-icon-box {
  width: 52px;
  height: 52px;
  border-radius: var(--radius-lg);
  background: var(--accent-primary-light);
  color: var(--accent-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  flex-shrink: 0;
  border: 1px solid var(--accent-primary-border);
}

.workspace-heading {
  font-size: 1.65rem;
  font-weight: 800;
  letter-spacing: -0.02em;
}

.workspace-description {
  font-size: 0.9rem;
  color: var(--text-secondary);
  margin-top: 0.2rem;
}

.workspace-actions {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.workspace-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.75rem;
  align-items: start;
  width: 100%;
}

@media (max-width: 900px) {
  .workspace-grid {
    grid-template-columns: 1fr;
  }
}

/* --------------------------------------------------------------------------
   Calculator Input Panel
   -------------------------------------------------------------------------- */
.calc-inputs-card {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.calc-action-buttons {
  display: flex;
  gap: 0.75rem;
  margin-top: 0.5rem;
}

/* --------------------------------------------------------------------------
   Calculator Result Card & Visualizations
   -------------------------------------------------------------------------- */
.calc-result-card {
  background: var(--bg-card);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-xl);
  padding: 1.75rem;
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
  position: sticky;
  top: calc(var(--header-height) + 1.5rem);
  box-shadow: var(--shadow-md);
}

.result-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.result-label {
  font-size: 0.8rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-muted);
}

.result-main-value {
  font-size: 2.5rem;
  font-weight: 800;
  letter-spacing: -0.03em;
  color: var(--accent-primary);
  line-height: 1.15;
  word-break: break-word;
  transition: all var(--transition-fast);
}

.result-sub-value {
  font-size: 0.95rem;
  color: var(--text-secondary);
  font-weight: 500;
}

.result-explanation-box {
  background: var(--bg-subtle);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 1rem;
  font-size: 0.875rem;
  line-height: 1.5;
}

.explanation-title {
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 0.25rem;
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

.formula-tag {
  font-family: var(--font-mono);
  background: var(--bg-surface);
  padding: 2px 6px;
  border-radius: var(--radius-xs);
  border: 1px solid var(--border-subtle);
  color: var(--accent-primary);
  font-size: 0.825rem;
}

/* Metric Breakdown Grid */
.breakdown-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.75rem;
}

.breakdown-item {
  background: var(--bg-subtle);
  padding: 0.75rem 1rem;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-subtle);
}

.breakdown-item-label {
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.breakdown-item-value {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-top: 0.2rem;
}

/* --------------------------------------------------------------------------
   Basic & Scientific Calculator Keypad
   -------------------------------------------------------------------------- */
/* --------------------------------------------------------------------------
   Basic Calculator Studio Workspace (Tactile Console & Companion)
   -------------------------------------------------------------------------- */
.basic-studio-layout {
  display: grid;
  grid-template-columns: 1fr 340px;
  gap: 1.5rem;
  align-items: start;
}

@media (max-width: 900px) {
  .basic-studio-layout {
    grid-template-columns: 1fr;
    max-width: 480px;
    margin: 0 auto;
  }
}

/* Left: Tactile Calculator Console */
.basic-console-card {
  background: var(--bg-card);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-2xl);
  padding: 1.35rem;
  box-shadow: var(--shadow-lg), 0 0 0 1px rgba(29, 78, 216, 0.03);
  display: flex;
  flex-direction: column;
  gap: 0.9rem;
}

/* LCD Console Status Rim */
.basic-console-rim {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 0.25rem 0.25rem 0.25rem;
}

.basic-rim-status {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.rim-status-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: #10b981;
  box-shadow: 0 0 0 2px rgba(16, 185, 129, 0.25);
  animation: pulse-ring 2s infinite;
}

.rim-mode-pill {
  font-size: 0.6875rem;
  font-weight: 700;
  font-family: var(--font-mono);
  color: var(--accent-primary);
  background: var(--accent-primary-light);
  border: 1px solid var(--accent-primary-border);
  border-radius: 4px;
  padding: 1px 6px;
}

.rim-mem-indicator {
  font-size: 0.6875rem;
  font-weight: 600;
  font-family: var(--font-mono);
  color: var(--text-muted);
  background: var(--bg-subtle);
  border: 1px solid var(--border-subtle);
  border-radius: 4px;
  padding: 1px 6px;
  transition: all var(--transition-fast);
}

.rim-mem-indicator.active {
  color: #f59e0b;
  background: rgba(245, 158, 11, 0.12);
  border-color: rgba(245, 158, 11, 0.3);
  font-weight: 700;
}

.rim-action-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  background: var(--bg-subtle);
  border: 1px solid var(--border-subtle);
  border-radius: 6px;
  padding: 3px 8px;
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--text-secondary);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.rim-action-btn svg {
  width: 13px;
  height: 13px;
}

.rim-action-btn:hover {
  background: var(--bg-surface-hover);
  color: var(--text-primary);
  border-color: var(--border-default);
}

/* Segmented LCD Display */
.basic-calc-display {
  background: var(--bg-input);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-xl);
  padding: 1rem 1.25rem;
  text-align: right;
  min-height: 105px;
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  word-break: break-all;
  box-shadow: inset 0 2px 4px rgba(0, 0, 0, 0.04);
}

.basic-calc-expression {
  font-family: var(--font-mono);
  font-size: 0.95rem;
  color: var(--text-muted);
  min-height: 1.4rem;
  line-height: 1.4;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.basic-calc-result {
  font-family: var(--font-mono);
  font-size: 2.25rem;
  font-weight: 700;
  color: var(--text-primary);
  letter-spacing: -0.02em;
  line-height: 1.15;
}

/* Tactile Memory Bar */
.basic-mem-bar {
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  gap: 0.35rem;
}

.mem-btn {
  height: 28px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--bg-subtle);
  border: 1px solid var(--border-subtle);
  border-radius: 6px;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 700;
  color: var(--text-secondary);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.mem-btn:hover:not(.disabled) {
  background: var(--bg-surface-hover);
  color: var(--text-primary);
  border-color: var(--border-default);
  transform: translateY(-1px);
}

.mem-btn.disabled {
  opacity: 0.45;
  cursor: not-allowed;
}

.mem-btn-ans {
  background: var(--accent-primary-light);
  color: var(--accent-primary);
  border-color: var(--accent-primary-border);
}

/* Keypad Grid & Buttons */
.basic-calc-keypad {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 0.55rem;
}

.calc-btn {
  height: 52px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.25rem;
  font-weight: 600;
  border-radius: var(--radius-lg);
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  color: var(--text-primary);
  box-shadow: 0 1px 2px rgba(15, 23, 42, 0.04);
  transition: all 120ms cubic-bezier(0.4, 0, 0.2, 1);
  user-select: none;
  cursor: pointer;
}

.calc-btn:hover {
  background: var(--bg-surface-hover);
  border-color: var(--border-default);
  transform: translateY(-1px);
  box-shadow: 0 3px 6px rgba(15, 23, 42, 0.06);
}

.calc-btn:active, .calc-btn.pressed {
  transform: scale(0.96) translateY(1px);
  background: var(--bg-surface-active);
  box-shadow: none;
}

.calc-btn-num {
  font-family: var(--font-mono);
  font-weight: 600;
}

.calc-btn-operator {
  background: var(--accent-primary-light);
  color: var(--accent-primary);
  border-color: var(--accent-primary-border);
  font-weight: 700;
  font-size: 1.35rem;
}

.calc-btn-operator:hover {
  background: var(--accent-primary);
  color: #ffffff;
  border-color: var(--accent-primary);
}

.calc-btn-action {
  background: var(--bg-subtle);
  color: var(--text-secondary);
  font-size: 1.1rem;
  font-weight: 600;
}

.calc-btn-clear {
  background: rgba(239, 68, 68, 0.1);
  color: #ef4444;
  border-color: rgba(239, 68, 68, 0.25);
  font-weight: 700;
}

.calc-btn-clear:hover {
  background: #ef4444;
  color: #ffffff;
  border-color: #ef4444;
}

.calc-btn-equal {
  background: linear-gradient(135deg, var(--accent-primary) 0%, #2563EB 100%);
  color: #ffffff;
  border: none;
  font-weight: 700;
  font-size: 1.45rem;
  box-shadow: 0 4px 12px rgba(29, 78, 216, 0.35);
}

.calc-btn-equal:hover {
  background: linear-gradient(135deg, var(--accent-secondary, #F97316) 0%, #EA580C 100%);
  box-shadow: 0 4px 14px rgba(249, 115, 22, 0.4);
}

/* Shortcuts Legend Footer */
.basic-shortcuts-footer {
  padding-top: 0.35rem;
  border-top: 1px solid var(--border-subtle);
}

.shortcuts-legend {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.35rem;
}

.legend-item {
  font-size: 0.72rem;
  color: var(--text-muted);
  display: inline-flex;
  align-items: center;
  gap: 3px;
}

.legend-item kbd {
  font-family: var(--font-mono);
  font-size: 0.65rem;
  font-weight: 700;
  padding: 1px 5px;
  background: var(--bg-subtle);
  border: 1px solid var(--border-default);
  border-radius: 4px;
  color: var(--text-secondary);
}

/* --------------------------------------------------------------------------
   Right: Companion Intelligence Card
   -------------------------------------------------------------------------- */
.basic-companion-card {
  background: var(--bg-card);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-2xl);
  padding: 1.25rem;
  box-shadow: var(--shadow-md);
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.companion-tabs-bar {
  display: flex;
  background: var(--bg-subtle);
  border: 1px solid var(--border-subtle);
  border-radius: 9px;
  padding: 3px;
  gap: 2px;
}

.companion-tab-btn {
  flex: 1;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.35rem;
  padding: 5px 8px;
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--text-secondary);
  background: transparent;
  border: 1px solid transparent;
  border-radius: 6px;
  cursor: pointer;
  transition: all var(--transition-fast);
  white-space: nowrap;
}

.companion-tab-btn:hover {
  color: var(--text-primary);
}

.companion-tab-btn.active {
  background: var(--bg-surface);
  color: var(--accent-primary);
  border-color: var(--border-subtle);
  box-shadow: 0 1px 2px rgba(15, 23, 42, 0.05);
  font-weight: 700;
}

.tape-count-chip {
  font-size: 0.625rem;
  font-weight: 800;
  padding: 0 5px;
  border-radius: 9999px;
  background: var(--accent-secondary, #F97316);
  color: #ffffff;
}

.companion-tab-pane {
  display: none;
  flex-direction: column;
  gap: 0.75rem;
}

.companion-tab-pane.active {
  display: flex;
}

/* Tape Section */
.tape-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.tape-title {
  font-size: 0.8125rem;
  font-weight: 700;
  color: var(--text-primary);
}

.tape-clear-btn {
  background: none;
  border: none;
  font-size: 0.72rem;
  font-weight: 600;
  color: var(--accent-primary);
  cursor: pointer;
  padding: 2px 6px;
  border-radius: 4px;
  transition: background var(--transition-fast);
}

.tape-clear-btn:hover {
  background: var(--accent-primary-light);
}

.tape-list-wrapper {
  max-height: 380px;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  padding-right: 4px;
}

.tape-item {
  background: var(--bg-subtle);
  border: 1px solid var(--border-subtle);
  border-radius: 8px;
  padding: 0.65rem 0.75rem;
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.tape-item:hover {
  background: var(--bg-surface-hover);
  border-color: var(--border-default);
  transform: translateX(2px);
}

.tape-item-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.6875rem;
  color: var(--text-muted);
}

.tape-recall-btn {
  background: none;
  border: none;
  font-size: 0.6875rem;
  font-weight: 700;
  color: var(--accent-primary);
  cursor: pointer;
  opacity: 0.8;
  padding: 1px 4px;
}

.tape-item:hover .tape-recall-btn {
  opacity: 1;
  text-decoration: underline;
}

.tape-item-expr {
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  color: var(--text-secondary);
  word-break: break-all;
}

.tape-item-result {
  font-family: var(--font-mono);
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--text-primary);
}

.tape-empty-state {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 2.5rem 1rem;
  text-align: center;
  color: var(--text-muted);
  gap: 0.35rem;
}

.tape-empty-icon svg {
  width: 28px;
  height: 28px;
  opacity: 0.4;
}

.tape-empty-text {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-secondary);
  margin: 0;
}

.tape-empty-sub {
  font-size: 0.75rem;
}

/* Quick Tools Grid */
.quick-tools-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0.65rem;
}

.quick-tool-card {
  background: var(--bg-subtle);
  border: 1px solid var(--border-subtle);
  border-radius: 8px;
  padding: 0.65rem 0.75rem;
  display: flex;
  flex-direction: column;
  gap: 0.3rem;
}

.quick-tool-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.quick-tool-name {
  font-size: 0.8125rem;
  font-weight: 700;
  color: var(--text-primary);
}

.quick-tool-badge {
  font-size: 0.625rem;
  font-weight: 700;
  padding: 1px 5px;
  border-radius: 4px;
  background: var(--accent-primary-light);
  color: var(--accent-primary);
}

.quick-tool-desc {
  font-size: 0.75rem;
  color: var(--text-muted);
  margin: 0;
  line-height: 1.3;
}

.quick-apply-btn {
  align-self: flex-start;
  margin-top: 0.2rem;
  background: var(--bg-surface);
  border: 1px solid var(--border-default);
  border-radius: 5px;
  padding: 3px 8px;
  font-size: 0.72rem;
  font-weight: 600;
  color: var(--text-primary);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.quick-apply-btn:hover {
  background: var(--accent-primary);
  color: #ffffff;
  border-color: var(--accent-primary);
}

/* Related Solvers List */
.related-solvers-list {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.related-solver-item {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  padding: 0.6rem 0.75rem;
  background: var(--bg-subtle);
  border: 1px solid var(--border-subtle);
  border-radius: 8px;
  text-decoration: none;
  color: inherit;
  transition: all var(--transition-fast);
}

.related-solver-item:hover {
  background: var(--bg-surface-hover);
  border-color: var(--border-default);
  transform: translateX(2px);
}

.related-solver-icon {
  width: 28px;
  height: 28px;
  min-width: 28px;
  border-radius: 7px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.related-solver-icon svg {
  width: 15px;
  height: 15px;
}

.related-solver-info {
  flex: 1;
  min-width: 0;
  display: flex;
  flex-direction: column;
}

.related-solver-name {
  font-size: 0.8125rem;
  font-weight: 700;
  color: var(--text-primary);
}

.related-solver-desc {
  font-size: 0.72rem;
  color: var(--text-muted);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.related-solver-arrow {
  font-size: 0.85rem;
  color: var(--accent-primary);
  font-weight: 700;
  transition: transform var(--transition-fast);
}

.related-solver-item:hover .related-solver-arrow {
  transform: translateX(2px);
}

/* --------------------------------------------------------------------------
   BMI Meter & Category Visualizer
   -------------------------------------------------------------------------- */
.bmi-gauge-wrapper {
  margin: 1rem 0;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.bmi-bar-track {
  height: 12px;
  border-radius: var(--radius-full);
  background: linear-gradient(to right, 
    #38bdf8 0%, #38bdf8 18.5%, 
    #10b981 18.5%, #10b981 24.9%, 
    #f59e0b 24.9%, #f59e0b 29.9%, 
    #ef4444 29.9%, #ef4444 100%
  );
  position: relative;
}

.bmi-indicator-pin {
  position: absolute;
  top: -4px;
  width: 20px;
  height: 20px;
  background: #ffffff;
  border: 3px solid var(--accent-primary);
  border-radius: var(--radius-full);
  transform: translateX(-50%);
  box-shadow: var(--shadow-md);
  transition: left var(--transition-smooth);
}

.bmi-scale-labels {
  display: flex;
  justify-content: space-between;
  font-size: 0.72rem;
  color: var(--text-muted);
  font-weight: 600;
}

/* --------------------------------------------------------------------------
   EMI & Loan Chart Visualizer
   -------------------------------------------------------------------------- */
.donut-chart-container {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1.5rem;
  padding: 1rem 0;
}

.chart-legend {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.legend-item {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  font-size: 0.85rem;
  font-weight: 500;
}

.legend-color-dot {
  width: 12px;
  height: 12px;
  border-radius: 3px;
  flex-shrink: 0;
}

/* --------------------------------------------------------------------------
   Dashboard Viewport & Calm Technical Blueprint Grid
   -------------------------------------------------------------------------- */
.dashboard-viewport {
  position: relative;
  width: 100%;
  min-height: 100%;
  overflow: hidden;
  margin: -2rem -2.5rem;
  padding: 2rem 2.5rem;
}

@media (max-width: 1024px) {
  .dashboard-viewport {
    margin: -1.5rem -1.25rem;
    padding: 1.5rem 1.25rem;
  }
}

@media (max-width: 768px) {
  .dashboard-viewport {
    margin: -1.25rem -1rem -5rem -1rem;
    padding: 1.25rem 1rem 5rem 1rem;
  }
}

/* Faint Blueprint Graph-Paper Grid (Calm, 4% Opacity) */
.dashboard-ambient-bg {
  display: none;
}

.dashboard-ambient-grid {
  position: absolute;
  inset: 0;
  pointer-events: none;
  z-index: 0;
  background-image: 
    linear-gradient(to right, rgba(29, 78, 216, 0.045) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(29, 78, 216, 0.045) 1px, transparent 1px);
  background-size: 24px 24px;
  mask-image: radial-gradient(ellipse 90% 75% at 50% 25%, black 40%, transparent 95%);
  -webkit-mask-image: radial-gradient(ellipse 90% 75% at 50% 25%, black 40%, transparent 95%);
}

[data-theme="dark"] .dashboard-ambient-grid {
  background-image: 
    linear-gradient(to right, rgba(34, 211, 238, 0.06) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(34, 211, 238, 0.06) 1px, transparent 1px);
  background-size: 24px 24px;
}

.dashboard-ambient-glow {
  position: absolute;
  pointer-events: none;
  z-index: 0;
  border-radius: 50%;
  filter: blur(120px);
}

.glow-top-left {
  top: -100px;
  left: 10%;
  width: 500px;
  height: 350px;
  background: radial-gradient(circle, rgba(29, 78, 216, 0.10) 0%, transparent 70%);
}

.glow-top-right {
  top: -60px;
  right: 12%;
  width: 480px;
  height: 340px;
  background: radial-gradient(circle, rgba(249, 115, 22, 0.08) 0%, transparent 70%);
}

.glow-mid-center {
  top: 45%;
  left: 30%;
  width: 500px;
  height: 300px;
  background: radial-gradient(circle, rgba(139, 92, 246, 0.06) 0%, transparent 70%);
}

[data-theme="dark"] .glow-top-left {
  background: radial-gradient(circle, rgba(34, 211, 238, 0.12) 0%, transparent 70%);
}
[data-theme="dark"] .glow-top-right {
  background: radial-gradient(circle, rgba(139, 92, 246, 0.12) 0%, transparent 70%);
}

.dashboard-content-layer {
  position: relative;
  z-index: 1;
}

/* --------------------------------------------------------------------------
   Dashboard Hero & Controls
   -------------------------------------------------------------------------- */
.dashboard-hero {
  text-align: center;
  padding: 2.75rem 1rem 1.25rem 1rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.95rem;
  position: relative;
}

/* --------------------------------------------------------------------------
   Premium Authenticated Hero & Luminous Welcome Showcase
   -------------------------------------------------------------------------- */
.hero-welcome-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.85rem;
  padding: 8px 18px 8px 10px;
  border-radius: 9999px;
  background: var(--bg-surface);
  border: 1.5px solid rgba(99, 102, 241, 0.25);
  box-shadow: 0 4px 20px -2px rgba(99, 102, 241, 0.15), 0 1px 3px rgba(15, 23, 42, 0.04);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  margin-bottom: 0.85rem;
  transition: all var(--transition-fast);
  position: relative;
  overflow: hidden;
}

.hero-welcome-badge::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: linear-gradient(90deg, #4285F4 0%, #34A853 33%, #FBBC05 66%, #EA4335 100%);
}

.hero-welcome-badge:hover {
  transform: translateY(-2px);
  border-color: rgba(99, 102, 241, 0.45);
  box-shadow: 0 8px 26px -4px rgba(99, 102, 241, 0.22);
}

.user-avatar-glow-ring {
  position: relative;
  width: 34px;
  height: 34px;
  border-radius: 50%;
  padding: 2px;
  background: linear-gradient(135deg, #4285F4 0%, #10B981 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.user-avatar-img {
  width: 100%;
  height: 100%;
  border-radius: 50%;
  object-fit: cover;
  background: var(--bg-card);
}

.user-status-online-dot {
  position: absolute;
  bottom: -1px;
  right: -1px;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: #10B981;
  border: 2px solid var(--bg-surface);
  box-shadow: 0 0 6px #10B981;
}

.user-welcome-meta {
  display: flex;
  align-items: center;
  gap: 0.65rem;
}

.user-welcome-label {
  font-size: 0.8125rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--text-primary);
}

.user-welcome-name {
  color: #4285F4;
  font-weight: 800;
}

.user-sync-status-pill {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  font-size: 0.6875rem;
  font-weight: 800;
  letter-spacing: 0.06em;
  padding: 3px 9px;
  border-radius: 9999px;
  background: rgba(16, 185, 129, 0.12);
  color: #10B981;
  border: 1px solid rgba(16, 185, 129, 0.3);
}

.sync-pulse-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: #10B981;
  animation: pulseDot 2s infinite ease-in-out;
}

.hero-eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.4rem 1.1rem;
  border-radius: var(--radius-full);
  background: var(--bg-surface);
  border: 1px solid var(--border-default);
  font-size: 0.75rem;
  font-weight: 800;
  letter-spacing: 0.08em;
  color: var(--accent-primary);
  box-shadow: 0 2px 8px rgba(15, 23, 42, 0.04);
  text-transform: uppercase;
}

.hero-pulse-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: #10B981;
  box-shadow: 0 0 0 2px rgba(16, 185, 129, 0.2);
  animation: pulseDot 2s infinite ease-in-out;
}

@keyframes pulseDot {
  0% { transform: scale(0.9); opacity: 0.8; }
  50% { transform: scale(1.3); opacity: 1; box-shadow: 0 0 10px #10B981; }
  100% { transform: scale(0.9); opacity: 0.8; }
}

.hero-title {
  font-size: 3.15rem;
  font-weight: 800;
  letter-spacing: -0.04em;
  line-height: 1.1;
  max-width: 860px;
  color: var(--text-primary);
  margin: 0;
}

.hero-highlight-text {
  background: linear-gradient(135deg, #2563EB 0%, #7C3AED 50%, #EC4899 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  display: inline-block;
  font-weight: 800;
}

[data-theme="dark"] .hero-highlight-text {
  background: linear-gradient(135deg, #38BDF8 0%, #818CF8 50%, #F472B6 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-subtitle {
  font-size: 1.075rem;
  color: var(--text-secondary);
  max-width: 680px;
  line-height: 1.6;
  font-weight: 450;
  margin: 0;
}

/* Floating Elevated Search Box */
.hero-search-box {
  width: 100%;
  max-width: 620px;
  position: relative;
  margin-top: 0.6rem;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.hero-search-input {
  width: 100%;
  height: 56px;
  padding: 0 4.5rem 0 3.4rem;
  font-size: 0.98rem;
  font-weight: 500;
  border-radius: 18px;
  background: var(--bg-surface);
  border: 1.5px solid var(--border-default);
  box-shadow: 0 4px 18px -2px rgba(15, 23, 42, 0.06), 0 1px 3px rgba(15, 23, 42, 0.03);
  color: var(--text-primary);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.hero-search-box:hover .hero-search-input {
  border-color: #6366F1;
  box-shadow: 0 0 0 4px rgba(99, 102, 241, 0.12), 0 8px 24px -4px rgba(99, 102, 241, 0.18);
  transform: translateY(-1px);
}

.hero-search-icon {
  position: absolute;
  left: 1.25rem;
  top: 50%;
  transform: translateY(-50%);
  color: #6366F1;
  display: flex;
  align-items: center;
  font-size: 1.2rem;
  transition: transform var(--transition-fast);
}

.hero-search-box:hover .hero-search-icon {
  transform: translateY(-50%) scale(1.1);
}

.hero-search-shortcut {
  position: absolute;
  right: 1.1rem;
  top: 50%;
  transform: translateY(-50%);
}

.hero-search-shortcut .kbd {
  background: var(--bg-subtle);
  border: 1px solid var(--border-default);
  padding: 4px 9px;
  border-radius: 8px;
  font-size: 0.75rem;
  font-weight: 700;
  color: var(--text-secondary);
  box-shadow: 0 1px 3px rgba(15, 23, 42, 0.04);
}

/* Trending Shortcuts Row with Luminous Dots */
.hero-trending-row {
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-top: 0.4rem;
}

.trending-badge {
  font-size: 0.6875rem;
  font-weight: 800;
  letter-spacing: 0.08em;
  color: var(--text-muted);
  text-transform: uppercase;
  padding: 3px 8px;
  border-radius: 6px;
  background: var(--bg-subtle);
}

.trending-link {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.38rem 0.85rem;
  font-size: 0.8rem;
  font-weight: 600;
  border-radius: 9999px;
  background: var(--bg-surface);
  border: 1px solid var(--border-default);
  color: var(--text-secondary);
  text-decoration: none;
  transition: all var(--transition-fast);
  box-shadow: 0 1px 3px rgba(15, 23, 42, 0.02);
}

.dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  display: inline-block;
  box-shadow: 0 0 6px currentColor;
}
.dot-blue    { background: #2563EB; color: rgba(37, 99, 235, 0.5); }
.dot-purple  { background: #7C3AED; color: rgba(124, 58, 237, 0.5); }
.dot-emerald { background: #10B981; color: rgba(16, 185, 129, 0.5); }
.dot-orange  { background: #F97316; color: rgba(249, 115, 22, 0.5); }
.dot-cyan    { background: #06B6D4; color: rgba(6, 182, 212, 0.5); }

.trending-link:hover {
  background: var(--bg-surface-hover);
  border-color: #6366F1;
  color: #6366F1;
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(99, 102, 241, 0.12);
}

/* --------------------------------------------------------------------------
   Platform Statistics Grid (Glassmorphism, High Contrast & Ambient Lighting)
   -------------------------------------------------------------------------- */
.platform-stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.25rem;
  margin: 1rem 0 2rem 0;
}

@media (max-width: 960px) {
  .platform-stats-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 520px) {
  .platform-stats-grid {
    grid-template-columns: 1fr;
  }
}

.stat-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-default);
  border-radius: 20px;
  padding: 1.5rem 1.6rem;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  transition: all var(--transition-fast);
  box-shadow: 0 2px 10px -2px rgba(15, 23, 42, 0.04);
  position: relative;
  overflow: hidden;
}

.stat-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  transition: opacity var(--transition-fast);
}

.stat-card-blue::before    { background: linear-gradient(90deg, #2563EB, #38BDF8); }
.stat-card-purple::before  { background: linear-gradient(90deg, #7C3AED, #C084FC); }
.stat-card-orange::before  { background: linear-gradient(90deg, #F97316, #FBBF24); }
.stat-card-emerald::before { background: linear-gradient(90deg, #10B981, #34D399); }

.stat-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 12px 28px -6px rgba(15, 23, 42, 0.09);
  border-color: rgba(99, 102, 241, 0.3);
}

.stat-card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.stat-label {
  font-size: 0.75rem;
  font-weight: 800;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.stat-icon-chip {
  width: 36px;
  height: 36px;
  border-radius: 11px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1rem;
  transition: transform var(--transition-fast);
}

.stat-card:hover .stat-icon-chip {
  transform: scale(1.1) rotate(5deg);
}

.stat-chip-blue {
  background: rgba(37, 99, 235, 0.12);
  color: #2563EB;
  border: 1px solid rgba(37, 99, 235, 0.2);
}

.stat-chip-purple {
  background: rgba(124, 58, 237, 0.12);
  color: #7C3AED;
  border: 1px solid rgba(124, 58, 237, 0.2);
}

.stat-chip-orange {
  background: rgba(249, 115, 22, 0.12);
  color: #F97316;
  border: 1px solid rgba(249, 115, 22, 0.2);
}

.stat-chip-emerald {
  background: rgba(16, 185, 129, 0.12);
  color: #10B981;
  border: 1px solid rgba(16, 185, 129, 0.2);
}

.stat-num {
  font-size: 2.45rem;
  font-weight: 800;
  letter-spacing: -0.04em;
  line-height: 1;
  margin-top: 0.2rem;
}

.stat-num-blue    { color: #2563EB; }
.stat-num-purple  { color: #7C3AED; }
.stat-num-orange  { color: #F97316; }
.stat-num-emerald { color: #10B981; }

[data-theme="dark"] .stat-num-blue    { color: #38BDF8; }
[data-theme="dark"] .stat-num-purple  { color: #A78BFA; }
[data-theme="dark"] .stat-num-orange  { color: #FB923C; }
[data-theme="dark"] .stat-num-emerald { color: #34D399; }

.stat-subtext {
  font-size: 0.8125rem;
  color: var(--text-secondary);
  font-weight: 500;
}

.stat-bar-track {
  width: 100%;
  height: 5px;
  border-radius: 999px;
  background: var(--bg-subtle);
  overflow: hidden;
  margin-top: 0.5rem;
}

.stat-bar-fill {
  height: 100%;
  border-radius: 999px;
  transition: width 0.8s cubic-bezier(0.16, 1, 0.3, 1);
}

.bar-blue    { background: linear-gradient(90deg, #2563EB, #38BDF8); }
.bar-purple  { background: linear-gradient(90deg, #7C3AED, #C084FC); }
.bar-orange  { background: linear-gradient(90deg, #F97316, #FBBF24); }
.bar-emerald { background: linear-gradient(90deg, #10B981, #34D399); }
  font-size: 0.775rem;
  color: var(--text-muted);
  font-weight: 500;
}

.stat-bar-track {
  width: 100%;
  height: 4px;
  background: var(--bg-subtle);
  border-radius: var(--radius-full);
  margin-top: 0.35rem;
  overflow: hidden;
}

.stat-bar-fill {
  height: 100%;
  border-radius: var(--radius-full);
}
.bar-blue    { background: linear-gradient(90deg, #3B82F6, #1D4ED8); }
.bar-purple  { background: linear-gradient(90deg, #A855F7, #7C3AED); }
.bar-orange  { background: linear-gradient(90deg, #FB923C, #EA580C); }
.bar-emerald { background: linear-gradient(90deg, #34D399, #059669); }

.stat-card-blue {
  border-top: 3px solid var(--cat-engineering);
}
.stat-card-purple {
  border-top: 3px solid var(--cat-math);
}
.stat-card-orange {
  border-top: 3px solid var(--accent-secondary);
}
.stat-card-emerald {
  border-top: 3px solid var(--cat-finance);
}

/* --------------------------------------------------------------------------
   Featured Calculator Hero Banner (Split with LCD Console Preview)
   -------------------------------------------------------------------------- */
.featured-calculator-card {
  background: linear-gradient(135deg, #1D4ED8 0%, #0F172A 100%);
  border: 1px solid rgba(29, 78, 216, 0.4);
  border-radius: var(--radius-2xl);
  padding: 2.25rem 2.5rem;
  position: relative;
  overflow: hidden;
  color: #FFFFFF;
  box-shadow: 0 12px 36px -6px rgba(29, 78, 216, 0.25);
  transition: all var(--transition-fast);
}

[data-theme="dark"] .featured-calculator-card {
  background: linear-gradient(135deg, #1E3A8A 0%, #070B16 100%);
  border-color: rgba(34, 211, 238, 0.35);
  box-shadow: 0 12px 36px -6px rgba(0, 0, 0, 0.6);
}

.featured-calculator-card:hover {
  transform: translateY(-3px);
  box-shadow: 0 16px 42px -6px rgba(29, 78, 216, 0.35);
}

.featured-card-grid {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 2rem;
  align-items: center;
}

@media (max-width: 900px) {
  .featured-card-grid {
    grid-template-columns: 1fr;
  }
}

.featured-card-body {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.featured-tag {
  display: inline-flex;
  align-items: center;
  font-size: 0.72rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  padding: 4px 10px;
  border-radius: 6px;
  background: #F97316;
  color: #FFFFFF;
  border: none;
  box-shadow: 0 2px 8px rgba(249, 115, 22, 0.4);
  align-self: flex-start;
}

.featured-title {
  font-size: 1.85rem;
  font-weight: 800;
  color: #FFFFFF;
  letter-spacing: -0.025em;
  line-height: 1.2;
}

.featured-desc {
  font-size: 0.95rem;
  color: rgba(255, 255, 255, 0.88);
  line-height: 1.55;
}

.featured-spec-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem;
  margin: 0.2rem 0;
}

.spec-pill {
  font-size: 0.72rem;
  font-weight: 600;
  background: rgba(255, 255, 255, 0.12);
  color: #FFFFFF;
  padding: 3px 9px;
  border-radius: 6px;
  border: 1px solid rgba(255, 255, 255, 0.2);
}

.btn-featured {
  background: #FFFFFF;
  color: #1D4ED8;
  font-weight: 700;
  padding: 0.75rem 1.4rem;
  border-radius: var(--radius-md);
  border: none;
  box-shadow: 0 4px 14px rgba(0, 0, 0, 0.15);
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  transition: all var(--transition-fast);
}

.btn-featured:hover {
  background: #F97316;
  color: #FFFFFF;
  transform: translateX(2px);
  box-shadow: 0 6px 18px rgba(249, 115, 22, 0.4);
}

/* LCD Console Preview Graphic */
.featured-lcd-preview {
  background: rgba(10, 16, 32, 0.85);
  border: 1px solid rgba(255, 255, 255, 0.18);
  border-radius: var(--radius-xl);
  padding: 1.25rem;
  display: flex;
  flex-direction: column;
  gap: 0.65rem;
  box-shadow: inset 0 2px 6px rgba(0, 0, 0, 0.5), 0 8px 24px rgba(0, 0, 0, 0.3);
}

.lcd-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  color: #94A3B8;
  letter-spacing: 0.05em;
}

.lcd-status {
  color: #34D399;
  font-weight: 700;
}

.lcd-expression {
  font-family: var(--font-mono);
  font-size: 0.9rem;
  color: #CBD5E1;
  text-align: right;
  overflow-x: auto;
  white-space: nowrap;
}

.lcd-result {
  font-family: var(--font-mono);
  font-size: 1.65rem;
  font-weight: 800;
  color: #38BDF8;
  text-align: right;
  line-height: 1.1;
  letter-spacing: -0.02em;
}

.lcd-mini-keypad {
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  gap: 4px;
  margin-top: 0.35rem;
  padding-top: 0.5rem;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.lcd-key {
  height: 26px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: 4px;
  font-size: 0.72rem;
  font-family: var(--font-mono);
  color: #E2E8F0;
  user-select: none;
}

.lcd-key-op {
  background: rgba(56, 189, 248, 0.15);
  color: #38BDF8;
  border-color: rgba(56, 189, 248, 0.3);
  font-weight: 700;
}

/* --------------------------------------------------------------------------
   Engineering Showcase & 10 Discipline Chips (Color & Density Overhaul)
   -------------------------------------------------------------------------- */
.engineering-showcase-section {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-top: 3px solid var(--cat-engineering);
  border-radius: var(--radius-2xl);
  padding: 1.85rem;
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
  box-shadow: 0 2px 6px -1px rgba(15, 23, 42, 0.04);
}

.section-header-compact {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 1rem;
  flex-wrap: wrap;
  margin-bottom: 0.85rem;
}

.section-micro-label {
  font-size: 0.7rem;
  font-weight: 800;
  letter-spacing: 0.08em;
  color: var(--accent-primary);
  text-transform: uppercase;
  display: inline-block;
  margin-bottom: 0.2rem;
}

.section-heading {
  font-size: 1.35rem;
  font-weight: 800;
  color: var(--text-primary);
  letter-spacing: -0.02em;
}

.section-subtext {
  font-size: 0.875rem;
  color: var(--text-secondary);
  margin-top: 0.25rem;
  max-width: 680px;
  line-height: 1.45;
}

.disciplines-chips-grid {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 0.75rem;
}

@media (max-width: 1024px) {
  .disciplines-chips-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

@media (max-width: 640px) {
  .disciplines-chips-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

.discipline-chip {
  background: var(--bg-app);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 0.75rem 0.85rem;
  display: flex;
  align-items: center;
  gap: 0.65rem;
  text-decoration: none;
  transition: all var(--transition-fast);
}

.discipline-chip-text {
  display: flex;
  flex-direction: column;
  line-height: 1.2;
}

.discipline-name {
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--text-primary);
}

.discipline-count {
  font-size: 0.7rem;
  font-weight: 500;
  color: var(--text-muted);
}

.discipline-chip-icon {
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.15rem;
  width: 32px;
  height: 32px;
  border-radius: 8px;
  flex-shrink: 0;
}

/* Individual Engineering Discipline Accents */
.chip-electrical .discipline-chip-icon    { background: #EFF6FF; color: #1D4ED8; }
.chip-mechanical .discipline-chip-icon    { background: #F1F5F9; color: #475569; }
.chip-civil .discipline-chip-icon         { background: #FFF7ED; color: #EA580C; }
.chip-computer .discipline-chip-icon      { background: #ECFDF5; color: #059669; }
.chip-chemical .discipline-chip-icon      { background: #F5F3FF; color: #7C3AED; }
.chip-automobile .discipline-chip-icon    { background: #FFF1F2; color: #E11D48; }
.chip-aerospace .discipline-chip-icon     { background: #F0F9FF; color: #0284C7; }
.chip-electronics .discipline-chip-icon   { background: #EEF2FF; color: #4F46E5; }
.chip-environmental .discipline-chip-icon { background: #F0FDF4; color: #16A34A; }
.chip-industrial .discipline-chip-icon    { background: #F0FDFA; color: #0D9488; }

.discipline-chip:hover {
  background: var(--bg-surface);
  border-color: var(--accent-primary);
  transform: translateY(-2px);
  box-shadow: 0 4px 14px -2px rgba(15, 23, 42, 0.08);
}

/* --------------------------------------------------------------------------
   Domain Cards Grid (Color-Coded 6 Domains)
   -------------------------------------------------------------------------- */
.domain-cards-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.25rem;
}

@media (max-width: 1024px) {
  .domain-cards-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 640px) {
  .domain-cards-grid {
    grid-template-columns: 1fr;
  }
}

.domain-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-xl);
  padding: 1.6rem;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  gap: 1.15rem;
  transition: all var(--transition-fast);
  box-shadow: 0 2px 6px -1px rgba(15, 23, 42, 0.04);
}

.domain-card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.domain-card-icon {
  width: 44px;
  height: 44px;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.25rem;
  border: 1px solid transparent;
}

.domain-card-badge {
  font-size: 0.75rem;
  font-weight: 700;
  color: var(--text-muted);
  background: var(--bg-subtle);
  padding: 3px 8px;
  border-radius: var(--radius-full);
  border: 1px solid var(--border-subtle);
}

.domain-card-title {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text-primary);
  letter-spacing: -0.015em;
  margin-top: 0.25rem;
}

.domain-card-desc {
  font-size: 0.825rem;
  color: var(--text-secondary);
  line-height: 1.5;
}

.domain-popular-chips {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin-top: 0.25rem;
}

.domain-mini-chip {
  font-size: 0.72rem;
  font-weight: 600;
  color: var(--text-secondary);
  background: var(--bg-subtle);
  border: 1px solid var(--border-subtle);
  padding: 3px 8px;
  border-radius: 6px;
  text-decoration: none;
  transition: all var(--transition-fast);
}

.domain-mini-chip:hover {
  background: var(--bg-surface-hover);
  color: var(--text-primary);
}

.domain-card-footer {
  padding-top: 0.75rem;
  border-top: 1px solid var(--border-subtle);
}

.domain-card-action {
  font-size: 0.825rem;
  font-weight: 700;
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: 0.25rem;
  transition: all var(--transition-fast);
}

.domain-card-action:hover {
  transform: translateX(3px);
}

/* Category Specific Color Rules for Domain Cards */
.domain-card[data-domain="math"] {
  border-top: 3px solid var(--cat-math);
}
.domain-card[data-domain="math"] .domain-card-icon {
  background: var(--cat-math-bg);
  color: var(--cat-math);
  border-color: var(--cat-math-border);
}
.domain-card[data-domain="math"] .domain-card-action {
  color: var(--cat-math);
}
.domain-card[data-domain="math"]:hover {
  border-color: var(--cat-math);
  box-shadow: 0 8px 24px -4px rgba(139, 92, 246, 0.18);
  transform: translateY(-3px);
}

.domain-card[data-domain="engineering"] {
  border-top: 3px solid var(--cat-engineering);
}
.domain-card[data-domain="engineering"] .domain-card-icon {
  background: var(--cat-engineering-bg);
  color: var(--cat-engineering);
  border-color: var(--cat-engineering-border);
}
.domain-card[data-domain="engineering"] .domain-card-action {
  color: var(--cat-engineering);
}
.domain-card[data-domain="engineering"]:hover {
  border-color: var(--cat-engineering);
  box-shadow: 0 8px 24px -4px rgba(29, 78, 216, 0.18);
  transform: translateY(-3px);
}

.domain-card[data-domain="finance"] {
  border-top: 3px solid var(--cat-finance);
}
.domain-card[data-domain="finance"] .domain-card-icon {
  background: var(--cat-finance-bg);
  color: var(--cat-finance);
  border-color: var(--cat-finance-border);
}
.domain-card[data-domain="finance"] .domain-card-action {
  color: var(--cat-finance);
}
.domain-card[data-domain="finance"]:hover {
  border-color: var(--cat-finance);
  box-shadow: 0 8px 24px -4px rgba(5, 150, 105, 0.18);
  transform: translateY(-3px);
}

.domain-card[data-domain="science"] {
  border-top: 3px solid var(--cat-science);
}
.domain-card[data-domain="science"] .domain-card-icon {
  background: var(--cat-science-bg);
  color: var(--cat-science);
  border-color: var(--cat-science-border);
}
.domain-card[data-domain="science"] .domain-card-action {
  color: var(--cat-science);
}
.domain-card[data-domain="science"]:hover {
  border-color: var(--cat-science);
  box-shadow: 0 8px 24px -4px rgba(2, 132, 199, 0.18);
  transform: translateY(-3px);
}

.domain-card[data-domain="health"] {
  border-top: 3px solid var(--cat-health);
}
.domain-card[data-domain="health"] .domain-card-icon {
  background: var(--cat-health-bg);
  color: var(--cat-health);
  border-color: var(--cat-health-border);
}
.domain-card[data-domain="health"] .domain-card-action {
  color: var(--cat-health);
}
.domain-card[data-domain="health"]:hover {
  border-color: var(--cat-health);
  box-shadow: 0 8px 24px -4px rgba(225, 29, 72, 0.18);
  transform: translateY(-3px);
}

.domain-card[data-domain="everyday"] {
  border-top: 3px solid var(--cat-everyday);
}
.domain-card[data-domain="everyday"] .domain-card-icon {
  background: var(--cat-everyday-bg);
  color: var(--cat-everyday);
  border-color: var(--cat-everyday-border);
}
.domain-card[data-domain="everyday"] .domain-card-action {
  color: var(--cat-everyday);
}
.domain-card[data-domain="everyday"]:hover {
  border-color: var(--cat-everyday);
  box-shadow: 0 8px 24px -4px rgba(217, 119, 6, 0.18);
  transform: translateY(-3px);
}

/* --------------------------------------------------------------------------
   Refined Color-Coded Calculator Card Design
   -------------------------------------------------------------------------- */
/* --------------------------------------------------------------------------
   Category Landing Page & Hero Banner (Modern Structured Layout)
   -------------------------------------------------------------------------- */
.cat-breadcrumb {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.8125rem;
  color: var(--text-muted);
  margin-bottom: 1rem;
}

.cat-breadcrumb-link {
  color: var(--text-secondary);
  text-decoration: none;
  font-weight: 500;
  transition: color var(--transition-fast);
}

.cat-breadcrumb-link:hover {
  color: var(--accent-primary);
}

.cat-breadcrumb-separator {
  color: var(--border-default);
}

.cat-breadcrumb-segment {
  color: var(--text-muted);
}

.cat-breadcrumb-current {
  font-weight: 700;
}

/* Category Hero Banner */
.category-hero-banner {
  background: var(--bg-card);
  border: 1px solid var(--border-default);
  border-top: 4px solid var(--cat-accent, var(--accent-primary));
  border-radius: var(--radius-2xl);
  padding: 1.5rem 1.75rem;
  box-shadow: var(--shadow-md);
  margin-bottom: 1.5rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1.5rem;
  flex-wrap: wrap;
}

.category-hero-main {
  display: flex;
  align-items: center;
  gap: 1.15rem;
  flex: 1;
  min-width: 280px;
}

.category-hero-icon-box {
  width: 52px;
  height: 52px;
  min-width: 52px;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.6rem;
  box-shadow: var(--shadow-sm);
}

.category-hero-icon-box svg {
  width: 26px;
  height: 26px;
}

.category-hero-content {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
}

.category-hero-title-row {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  flex-wrap: wrap;
}

.category-hero-title {
  font-size: 1.65rem;
  font-weight: 800;
  letter-spacing: -0.03em;
  color: var(--text-primary);
  margin: 0;
}

.category-hero-desc {
  font-size: 0.875rem;
  color: var(--text-secondary);
  margin: 0;
  line-height: 1.45;
  max-width: 600px;
}

.category-hero-stats {
  display: flex;
  align-items: center;
  gap: 0.65rem;
}

.cat-stat-pill {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 0.55rem 1rem;
  background: var(--bg-subtle);
  border: 1px solid var(--border-subtle);
  border-radius: 10px;
  min-width: 75px;
}

.cat-stat-num {
  font-size: 1.15rem;
  font-weight: 800;
  color: var(--text-primary);
  font-family: var(--font-mono);
  line-height: 1.1;
}

.cat-stat-lbl {
  font-size: 0.6875rem;
  font-weight: 600;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-top: 2px;
}

/* Category Filter Toolbar */
.category-filter-toolbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
  margin-bottom: 1.75rem;
}

.tab-chip {
  font-size: 0.65rem;
  font-weight: 700;
  padding: 0.5px 5px;
  border-radius: 9999px;
  background: var(--bg-subtle);
  color: var(--text-muted);
  margin-left: 3px;
}

.segment-btn.active .tab-chip {
  background: var(--accent-primary-light);
  color: var(--accent-primary);
}

.cat-search-box {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  background: var(--bg-surface);
  border: 1px solid var(--border-default);
  border-radius: 9px;
  padding: 0 0.75rem;
  width: 260px;
  height: 38px;
  box-shadow: var(--shadow-xs);
  transition: all var(--transition-fast);
}

.cat-search-box:focus-within {
  border-color: var(--accent-primary);
  box-shadow: 0 0 0 3px var(--accent-primary-light);
}

.cat-search-icon {
  color: var(--text-muted);
  display: flex;
  align-items: center;
}

.cat-search-icon svg {
  width: 15px;
  height: 15px;
}

.cat-search-input {
  border: none;
  background: transparent;
  width: 100%;
  font-size: 0.8125rem;
  color: var(--text-primary);
  outline: none;
}

.cat-section-group {
  margin-bottom: 2.25rem;
}

.cat-section-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 0.85rem;
  padding-bottom: 0.4rem;
  border-bottom: 1px solid var(--border-subtle);
}

.cat-section-title-wrap {
  display: flex;
  align-items: center;
  gap: 0.6rem;
}

.cat-section-accent-bar {
  width: 3.5px;
  height: 16px;
  border-radius: 2px;
}

.cat-section-title {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--text-primary);
  letter-spacing: -0.01em;
  margin: 0;
}

.cat-empty-search {
  padding: 3.5rem 1rem;
  text-align: center;
  background: var(--bg-card);
  border: 1px dashed var(--border-default);
  border-radius: var(--radius-xl);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
}

.cat-empty-icon svg {
  width: 32px;
  height: 32px;
  opacity: 0.4;
  color: var(--text-muted);
}

.cat-empty-title {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--text-primary);
  margin: 0;
}

.cat-empty-sub {
  font-size: 0.825rem;
  color: var(--text-muted);
  margin: 0;
}

/* Cards Grid */
.cards-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 1.15rem;
}

.calc-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-xl);
  padding: 1.25rem;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  gap: 1rem;
  text-decoration: none;
  color: inherit;
  cursor: pointer;
  transition: all var(--transition-fast);
  position: relative;
  box-shadow: 0 2px 6px -1px rgba(15, 23, 42, 0.04);
}

.calc-card:hover {
  transform: translateY(-3px);
  border-color: var(--card-accent, var(--accent-primary));
  box-shadow: 0 8px 24px -4px rgba(15, 23, 42, 0.1);
}

/* Specific Category Colored Borders & Icons for Calculator Cards */
.calc-card[data-cat="math"], .calc-card[data-cat="algebra"], .calc-card[data-cat="geometry"], .calc-card[data-cat="trigonometry"] {
  border-top: 3px solid var(--cat-math);
}
.calc-card[data-cat="math"] .calc-card-icon, .calc-card[data-cat="algebra"] .calc-card-icon, .calc-card[data-cat="geometry"] .calc-card-icon, .calc-card[data-cat="trigonometry"] .calc-card-icon {
  background: var(--cat-math-bg);
  color: var(--cat-math);
  border: 1px solid var(--cat-math-border);
}
.calc-card[data-cat="math"]:hover {
  border-color: var(--cat-math);
  box-shadow: 0 8px 24px -4px rgba(139, 92, 246, 0.18);
}

.calc-card[data-cat="engineering"], .calc-card[data-cat="electrical"], .calc-card[data-cat="mechanical"], .calc-card[data-cat="civil"], .calc-card[data-cat="computer"] {
  border-top: 3px solid var(--cat-engineering);
}
.calc-card[data-cat="engineering"] .calc-card-icon, .calc-card[data-cat="electrical"] .calc-card-icon, .calc-card[data-cat="mechanical"] .calc-card-icon, .calc-card[data-cat="civil"] .calc-card-icon, .calc-card[data-cat="computer"] .calc-card-icon {
  background: var(--cat-engineering-bg);
  color: var(--cat-engineering);
  border: 1px solid var(--cat-engineering-border);
}
.calc-card[data-cat="engineering"]:hover {
  border-color: var(--cat-engineering);
  box-shadow: 0 8px 24px -4px rgba(29, 78, 216, 0.18);
}

.calc-card[data-cat="finance"], .calc-card[data-cat="business"], .calc-card[data-cat="investment"] {
  border-top: 3px solid var(--cat-finance);
}
.calc-card[data-cat="finance"] .calc-card-icon, .calc-card[data-cat="business"] .calc-card-icon, .calc-card[data-cat="investment"] .calc-card-icon {
  background: var(--cat-finance-bg);
  color: var(--cat-finance);
  border: 1px solid var(--cat-finance-border);
}
.calc-card[data-cat="finance"]:hover {
  border-color: var(--cat-finance);
  box-shadow: 0 8px 24px -4px rgba(5, 150, 105, 0.18);
}

.calc-card[data-cat="science"], .calc-card[data-cat="physics"], .calc-card[data-cat="chemistry"], .calc-card[data-cat="statistics"] {
  border-top: 3px solid var(--cat-science);
}
.calc-card[data-cat="science"] .calc-card-icon, .calc-card[data-cat="physics"] .calc-card-icon, .calc-card[data-cat="chemistry"] .calc-card-icon, .calc-card[data-cat="statistics"] .calc-card-icon {
  background: var(--cat-science-bg);
  color: var(--cat-science);
  border: 1px solid var(--cat-science-border);
}
.calc-card[data-cat="science"]:hover {
  border-color: var(--cat-science);
  box-shadow: 0 8px 24px -4px rgba(2, 132, 199, 0.18);
}

.calc-card[data-cat="health"], .calc-card[data-cat="fitness"], .calc-card[data-cat="education"] {
  border-top: 3px solid var(--cat-health);
}
.calc-card[data-cat="health"] .calc-card-icon, .calc-card[data-cat="fitness"] .calc-card-icon, .calc-card[data-cat="education"] .calc-card-icon {
  background: var(--cat-health-bg);
  color: var(--cat-health);
  border: 1px solid var(--cat-health-border);
}
.calc-card[data-cat="health"]:hover {
  border-color: var(--cat-health);
  box-shadow: 0 8px 24px -4px rgba(225, 29, 72, 0.18);
}

.calc-card[data-cat="everyday"], .calc-card[data-cat="converters"], .calc-card[data-cat="home-lifestyle"], .calc-card[data-cat="date_time"] {
  border-top: 3px solid var(--cat-everyday);
}
.calc-card[data-cat="everyday"] .calc-card-icon, .calc-card[data-cat="converters"] .calc-card-icon, .calc-card[data-cat="home-lifestyle"] .calc-card-icon, .calc-card[data-cat="date_time"] .calc-card-icon {
  background: var(--cat-everyday-bg);
  color: var(--cat-everyday);
  border: 1px solid var(--cat-everyday-border);
}
.calc-card[data-cat="everyday"]:hover {
  border-color: var(--cat-everyday);
  box-shadow: 0 8px 24px -4px rgba(217, 119, 6, 0.18);
}

.calc-card-top {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
}

.calc-card-icon {
  width: 38px;
  height: 38px;
  border-radius: 9px;
  background: var(--bg-subtle);
  color: var(--accent-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.2rem;
  border: 1px solid var(--border-subtle);
  transition: transform var(--transition-fast);
}

.calc-card:hover .calc-card-icon {
  transform: scale(1.06);
}

.calc-card-favorite-btn {
  background: transparent;
  color: var(--text-muted);
  width: 30px;
  height: 30px;
  border-radius: 6px;
  display: flex;
  align-items: center;
  justify-content: center;
  border: none;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.calc-card-favorite-btn:hover, .calc-card-favorite-btn.active {
  color: #f59e0b;
  background: rgba(245, 158, 11, 0.1);
}

.calc-card-title {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 0.25rem;
  letter-spacing: -0.01em;
}

.calc-card-desc {
  font-size: 0.8rem;
  color: var(--text-secondary);
  line-height: 1.45;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.calc-card-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 0.5rem;
  border-top: 1px solid var(--border-subtle);
}

.calc-card-arrow {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 24px;
  height: 24px;
  border-radius: 6px;
  color: var(--text-muted);
  transition: all var(--transition-fast);
}

.calc-card-category {
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.calc-card-arrow {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 24px;
  height: 24px;
  border-radius: 6px;
  color: var(--text-muted);
  transition: all var(--transition-fast);
}

.calc-card:hover .calc-card-arrow {
  color: var(--accent-primary);
  transform: translateX(3px);
}

/* History List Items */
.history-list {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.history-item-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 1rem 1.25rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  transition: all var(--transition-fast);
}

.history-item-card:hover {
  border-color: var(--border-default);
  box-shadow: var(--shadow-sm);
}

.history-item-info {
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
  min-width: 0;
}

.history-item-title {
  font-size: 0.825rem;
  font-weight: 600;
  color: var(--text-muted);
}

.history-item-expr {
  font-size: 0.95rem;
  color: var(--text-secondary);
  font-family: var(--font-mono);
}

.history-item-result {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--accent-primary);
  font-family: var(--font-mono);
}

.history-item-actions {
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

/* ==========================================================================
   PRO SCIENTIFIC CALCULATOR SPECIALIZED STYLES
   ========================================================================== */

.pro-sci-wrapper {
  display: grid;
  grid-template-columns: minmax(320px, 580px) minmax(280px, 340px);
  gap: 1.5rem;
  align-items: start;
  justify-content: center;
  margin: 0 auto;
  width: 100%;
}

@media (max-width: 1024px) {
  .pro-sci-wrapper {
    grid-template-columns: minmax(320px, 600px);
  }
}

.pro-sci-console {
  background: var(--bg-card);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-2xl);
  padding: 1.25rem;
  box-shadow: 0 12px 32px -8px rgba(0, 0, 0, 0.08), 0 4px 12px -2px rgba(0, 0, 0, 0.04);
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
}

.pro-sci-display {
  background: var(--bg-surface);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-xl);
  padding: 1rem 1.25rem;
  box-shadow: inset 0 2px 4px rgba(0, 0, 0, 0.03);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  min-height: 105px;
}

.pro-sci-display-top {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.75rem;
  color: var(--text-muted);
  font-family: var(--font-mono);
}

.pro-sci-expr {
  font-family: var(--font-mono);
  font-size: 1.05rem;
  color: var(--text-secondary);
  text-align: right;
  overflow-x: auto;
  white-space: nowrap;
  padding: 2px 0;
  scrollbar-width: none;
}
.pro-sci-expr::-webkit-scrollbar {
  display: none;
}

.pro-sci-res {
  font-family: var(--font-mono);
  font-size: 2.15rem;
  font-weight: 800;
  color: var(--text-primary);
  text-align: right;
  overflow-x: auto;
  white-space: nowrap;
  letter-spacing: -0.02em;
  line-height: 1.2;
  scrollbar-width: none;
}
.pro-sci-res::-webkit-scrollbar {
  display: none;
}

.pro-sci-keypad {
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  gap: 0.45rem;
}

.pro-btn {
  height: 44px;
  min-height: 44px;
  max-height: 44px;
  aspect-ratio: auto !important;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-md);
  font-family: var(--font-sans);
  font-size: 0.925rem;
  font-weight: 600;
  border: 1px solid var(--border-subtle);
  background: var(--bg-surface);
  color: var(--text-primary);
  cursor: pointer;
  user-select: none;
  transition: all 100ms ease;
  box-shadow: 0 1px 2px rgba(0, 0, 0, 0.04);
}

.pro-btn:hover {
  background: var(--bg-hover);
  border-color: var(--border-hover);
  transform: translateY(-1px);
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.08);
}

.pro-btn:active {
  transform: translateY(0);
  box-shadow: none;
}

.pro-btn-fn {
  background: var(--bg-subtle);
  color: var(--text-secondary);
  font-size: 0.85rem;
  font-weight: 600;
}

.pro-btn-num {
  font-size: 1.15rem;
  font-weight: 700;
  background: var(--bg-card);
}

.pro-btn-op {
  background: rgba(99, 102, 241, 0.08);
  color: var(--accent-primary);
  font-size: 1.2rem;
  font-weight: 700;
  border-color: rgba(99, 102, 241, 0.15);
}

.pro-btn-op:hover {
  background: rgba(99, 102, 241, 0.15);
}

.pro-btn-clear {
  color: var(--accent-danger);
  background: rgba(239, 68, 68, 0.06);
  border-color: rgba(239, 68, 68, 0.15);
  font-weight: 700;
}

.pro-btn-clear:hover {
  background: rgba(239, 68, 68, 0.12);
}

.pro-btn-eval {
  background: var(--accent-primary);
  color: #ffffff;
  font-size: 1.35rem;
  font-weight: 800;
  border: none;
  box-shadow: 0 4px 12px rgba(99, 102, 241, 0.3);
}

.pro-btn-eval:hover {
  background: var(--accent-primary-hover, #4f46e5);
  color: #ffffff;
  box-shadow: 0 6px 16px rgba(99, 102, 241, 0.4);
}

.pro-sci-sidecard {
  background: var(--bg-card);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-2xl);
  padding: 1.25rem;
  box-shadow: 0 8px 24px -6px rgba(0, 0, 0, 0.06);
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
  height: 100%;
}

/* ==========================================================================
   ENHANCED UTILITY VIEWS: FAVORITES, HISTORY, RECENTS, SETTINGS
   ========================================================================== */

/* --------------------------------------------------------------------------
   Hero Utility Banner (Favorites / History / Recents / Settings)
   -------------------------------------------------------------------------- */
.util-hero-card {
  background: var(--bg-card);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-2xl);
  padding: 1.75rem 2rem;
  margin-bottom: 2rem;
  position: relative;
  overflow: hidden;
  box-shadow: 0 4px 20px -4px rgba(15, 23, 42, 0.04);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
}

.util-hero-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--accent-primary, #6366f1), #8b5cf6, #ec4899);
}

.util-hero-main {
  display: flex;
  align-items: center;
  gap: 1.25rem;
}

.util-hero-icon {
  width: 58px;
  height: 58px;
  border-radius: var(--radius-xl);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.75rem;
  flex-shrink: 0;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
}

.util-hero-title {
  font-size: 1.65rem;
  font-weight: 800;
  letter-spacing: -0.025em;
  color: var(--text-primary);
  margin: 0 0 0.25rem 0;
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.util-hero-desc {
  font-size: 0.925rem;
  color: var(--text-secondary);
  margin: 0;
}

.util-hero-stats {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  flex-wrap: wrap;
}

.util-stat-pill {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.45rem 0.9rem;
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: 999px;
  font-size: 0.8125rem;
  font-weight: 600;
  color: var(--text-secondary);
}

.util-stat-pill strong {
  color: var(--text-primary);
  font-weight: 700;
}

/* --------------------------------------------------------------------------
   Interactive Category Filter Bar & Toolbar
   -------------------------------------------------------------------------- */
.util-filter-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  margin-bottom: 1.5rem;
  flex-wrap: wrap;
}

.util-filter-chips {
  display: flex;
  align-items: center;
  gap: 0.45rem;
  flex-wrap: wrap;
}

.filter-chip-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.35rem 0.85rem;
  border-radius: 999px;
  font-size: 0.8125rem;
  font-weight: 600;
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  color: var(--text-secondary);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.filter-chip-btn:hover {
  background: var(--bg-hover);
  color: var(--text-primary);
  border-color: var(--border-default);
}

.filter-chip-btn.active {
  background: var(--accent-primary);
  color: #ffffff;
  border-color: var(--accent-primary);
  box-shadow: 0 2px 8px rgba(99, 102, 241, 0.25);
}

.filter-chip-btn .chip-count {
  font-size: 0.7rem;
  padding: 1px 6px;
  border-radius: 999px;
  background: rgba(0, 0, 0, 0.08);
  font-weight: 700;
}

.filter-chip-btn.active .chip-count {
  background: rgba(255, 255, 255, 0.25);
}

/* --------------------------------------------------------------------------
   Enhanced Calculation History Cards & Timeline
   -------------------------------------------------------------------------- */
.history-timeline-group {
  margin-bottom: 1.75rem;
}

.history-timeline-header {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 0.85rem;
  padding-bottom: 0.4rem;
  border-bottom: 1px solid var(--border-subtle);
}

.history-timeline-tag {
  font-size: 0.75rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--text-muted);
}

.history-card-item {
  background: var(--bg-card);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-xl);
  padding: 1.15rem 1.35rem;
  margin-bottom: 0.75rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.25rem;
  transition: all var(--transition-fast);
  box-shadow: 0 1px 3px rgba(15, 23, 42, 0.02);
}

.history-card-item:hover {
  border-color: var(--accent-primary-border, rgba(99, 102, 241, 0.3));
  box-shadow: 0 4px 14px -2px rgba(15, 23, 42, 0.06);
  transform: translateY(-1px);
}

.history-card-left {
  display: flex;
  align-items: center;
  gap: 1rem;
  min-width: 0;
}

.history-card-icon {
  width: 42px;
  height: 42px;
  border-radius: var(--radius-lg);
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.2rem;
  flex-shrink: 0;
}

.history-card-details {
  min-width: 0;
}

.history-card-header-row {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  margin-bottom: 0.2rem;
}

.history-card-name {
  font-weight: 700;
  font-size: 0.95rem;
  color: var(--text-primary);
}

.history-card-expr {
  font-family: var(--font-mono);
  font-size: 0.875rem;
  color: var(--text-secondary);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.history-card-right {
  display: flex;
  align-items: center;
  gap: 0.85rem;
  flex-shrink: 0;
}

.history-card-res {
  font-family: var(--font-mono);
  font-size: 1.2rem;
  font-weight: 800;
  color: var(--accent-primary);
  background: var(--accent-primary-light);
  border: 1px solid var(--accent-primary-border);
  padding: 0.35rem 0.85rem;
  border-radius: var(--radius-md);
  text-align: right;
}

/* --------------------------------------------------------------------------
   Enhanced Settings Section Cards & Visual Previews
   -------------------------------------------------------------------------- */
.settings-grid-container {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  max-width: 820px;
  margin: 0 auto;
}

.settings-card-enhanced {
  background: var(--bg-card);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-2xl);
  padding: 1.5rem 1.75rem;
  box-shadow: 0 2px 10px -2px rgba(15, 23, 42, 0.03);
}

.settings-section-top {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 1.25rem;
  padding-bottom: 0.85rem;
  border-bottom: 1px solid var(--border-subtle);
}

.settings-section-icon {
  width: 34px;
  height: 34px;
  border-radius: var(--radius-md);
  background: var(--accent-primary-light);
  color: var(--accent-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
}

.settings-section-heading {
  font-size: 1.125rem;
  font-weight: 800;
  color: var(--text-primary);
  margin: 0;
}

.settings-row-modern {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.85rem 0;
  border-bottom: 1px solid var(--border-subtle);
}

.settings-row-modern:last-child {
  border-bottom: none;
  padding-bottom: 0;
}

.settings-row-info {
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
  padding-right: 1.5rem;
}

.settings-row-label {
  font-size: 0.925rem;
  font-weight: 700;
  color: var(--text-primary);
}

.settings-row-desc {
  font-size: 0.8125rem;
  color: var(--text-muted);
  line-height: 1.4;
}

.theme-preview-cards {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
  margin-top: 0.75rem;
}

.theme-card-option {
  border: 2px solid var(--border-subtle);
  border-radius: var(--radius-xl);
  padding: 0.85rem;
  cursor: pointer;
  background: var(--bg-surface);
  transition: all var(--transition-fast);
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.theme-card-option:hover {
  border-color: var(--border-default);
  background: var(--bg-hover);
}

.theme-card-option.active {
  border-color: var(--accent-primary);
  background: var(--accent-primary-light);
  box-shadow: 0 0 0 1px var(--accent-primary);
}

.theme-thumb {
  height: 60px;
  border-radius: var(--radius-md);
  border: 1px solid rgba(0, 0, 0, 0.1);
  display: flex;
  overflow: hidden;
}

.theme-thumb-light {
  background: #f8fafc;
}
.theme-thumb-light .thumb-side {
  width: 25%;
  background: #ffffff;
  border-right: 1px solid #e2e8f0;
}
.theme-thumb-light .thumb-body {
  flex: 1;
  padding: 6px;
  display: flex;
  flex-direction: column;
  gap: 4px;
}
.theme-thumb-light .thumb-bar {
  height: 6px;
  background: #3b82f6;
  border-radius: 2px;
  width: 60%;
}
.theme-thumb-light .thumb-card {
  height: 24px;
  background: #ffffff;
  border: 1px solid #e2e8f0;
  border-radius: 4px;
}

.theme-thumb-dark {
  background: #0f172a;
}
.theme-thumb-dark .thumb-side {
  width: 25%;
  background: #1e293b;
  border-right: 1px solid #334155;
}
.theme-thumb-dark .thumb-body {
  flex: 1;
  padding: 6px;
  display: flex;
  flex-direction: column;
  gap: 4px;
}
.theme-thumb-dark .thumb-bar {
  height: 6px;
  background: #6366f1;
  border-radius: 2px;
  width: 60%;
}
.theme-thumb-dark .thumb-card {
  height: 24px;
  background: #1e293b;
  border: 1px solid #334155;
  border-radius: 4px;
}

/* --------------------------------------------------------------------------
   Unit Converter Multi-Comparison Table
   -------------------------------------------------------------------------- */
.converter-table-container {
  margin-top: 1rem;
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-subtle);
  overflow: hidden;
  background: var(--bg-surface);
}

.converter-table-header {
  display: grid;
  grid-template-columns: 1fr 1fr;
  padding: 0.5rem 0.85rem;
  background: var(--bg-subtle);
  border-bottom: 1px solid var(--border-subtle);
  font-size: 0.72rem;
  font-weight: 700;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.converter-table-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  padding: 0.55rem 0.85rem;
  border-bottom: 1px solid var(--border-subtle);
  font-size: 0.825rem;
  align-items: center;
  transition: background var(--transition-fast);
}

.converter-table-row:last-child {
  border-bottom: none;
}

.converter-table-row:hover {
  background: var(--bg-hover);
}

.converter-table-row.active-row {
  background: var(--accent-primary-light);
  font-weight: 700;
  color: var(--accent-primary);
}

/* ==========================================================================
   COMPREHENSIVE MOBILE RESPONSIVE OPTIMIZATIONS (< 768px)
   ========================================================================== */
@media (max-width: 768px) {
  /* 1. Hero Section Compact Scaling */
  .dashboard-hero {
    padding: 1.5rem 0.5rem 0.75rem 0.5rem;
    gap: 0.75rem;
  }

  .hero-eyebrow {
    font-size: 0.65rem;
    padding: 0.25rem 0.75rem;
  }

  .hero-title {
    font-size: 1.85rem;
    line-height: 1.18;
    letter-spacing: -0.02em;
  }

  .hero-subtitle {
    font-size: 0.875rem;
    line-height: 1.45;
  }

  .hero-search-box {
    margin-top: 0.2rem;
  }

  .hero-search-input {
    height: 46px;
    font-size: 0.85rem;
    padding: 0 2.5rem 0 2.75rem;
    border-radius: var(--radius-lg);
  }

  .hero-search-icon {
    left: 0.95rem;
    font-size: 0.95rem;
  }

  .hero-search-shortcut {
    display: none;
  }

  .hero-trending-row {
    gap: 0.35rem;
  }

  .trending-badge {
    font-size: 0.625rem;
    width: 100%;
    text-align: center;
    margin-bottom: 2px;
  }

  .trending-link {
    font-size: 0.72rem;
    padding: 0.25rem 0.6rem;
  }

  /* 2. Platform Stats Grid (2 Columns on Mobile) */
  .platform-stats-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 0.75rem;
  }

  .stat-card {
    padding: 0.95rem 1rem;
    border-radius: var(--radius-lg);
  }

  .stat-num {
    font-size: 1.65rem;
  }

  .stat-label {
    font-size: 0.7rem;
  }

  .stat-subtext {
    font-size: 0.7rem;
  }

  /* 3. Featured Card Mobile Stack */
  .featured-calculator-card {
    padding: 1.25rem;
    border-radius: var(--radius-xl);
  }

  .featured-title {
    font-size: 1.35rem;
  }

  .featured-desc {
    font-size: 0.85rem;
  }

  .featured-lcd-preview {
    padding: 0.85rem;
  }

  .lcd-expression {
    font-size: 0.8rem;
  }

  .lcd-result {
    font-size: 1.35rem;
  }

  .lcd-key {
    height: 24px;
    font-size: 0.65rem;
  }

  /* 4. Engineering Disciplines & Domain Cards Grid */
  .disciplines-chips-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 0.5rem;
  }

  .discipline-chip {
    padding: 0.6rem 0.65rem;
    gap: 0.5rem;
  }

  .discipline-name {
    font-size: 0.78rem;
  }

  .domain-cards-grid {
    grid-template-columns: 1fr;
    gap: 0.85rem;
  }

  .domain-card {
    padding: 1.25rem;
    border-radius: var(--radius-lg);
  }

  /* 5. Calculators Directory Grid */
  .cards-grid {
    grid-template-columns: 1fr;
    gap: 0.75rem;
  }

  .calc-card {
    padding: 1rem;
    border-radius: var(--radius-lg);
  }

  /* 6. Dual Column Calculator Workspaces Stack */
  .workspace-grid {
    grid-template-columns: 1fr !important;
    gap: 1.25rem;
  }

  .workspace-header {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.85rem;
    margin-bottom: 1rem;
  }

  .workspace-heading {
    font-size: 1.35rem;
  }

  .workspace-icon-box {
    width: 44px;
    height: 44px;
    font-size: 1.25rem;
  }

  .calc-result-card {
    position: static;
    padding: 1.25rem;
    border-radius: var(--radius-lg);
  }

  .result-main-value {
    font-size: 1.85rem;
  }

  /* 7. Basic & Scientific Keypads on Mobile */
  .basic-studio-layout {
    grid-template-columns: 1fr !important;
  }

  .basic-btn {
    height: 48px;
    font-size: 1.05rem;
  }

  .pro-sci-console {
    padding: 0.85rem;
    border-radius: var(--radius-lg);
  }

  .pro-sci-keypad {
    gap: 0.3rem;
  }

  .pro-btn {
    height: 38px;
    min-height: 38px;
    font-size: 0.78rem;
    padding: 0 2px;
  }

  .pro-btn-num {
    font-size: 0.95rem;
  }

  .pro-btn-eval {
    font-size: 1.1rem;
  }

  /* 8. Category Hero & Filters */
  .category-hero-banner {
    flex-direction: column;
    align-items: flex-start;
    padding: 1.25rem;
    gap: 1rem;
  }

  .category-hero-title {
    font-size: 1.35rem;
  }

  .category-hero-stats {
    width: 100%;
    justify-content: space-between;
  }

  .cat-stat-pill {
    flex: 1;
    min-width: 0;
    padding: 0.45rem 0.5rem;
  }

  .cat-search-box {
    width: 100%;
  }

  .category-filter-toolbar {
    flex-direction: column;
    align-items: stretch;
    gap: 0.75rem;
  }
}