/* --- Modern NDTM Simulation Styles --- */

/* Base Styles */
* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: 'Inter', system-ui, sans-serif;
  background: #fff;
  min-height: 100vh;
  color: #18181b;
  padding: 0.25rem; /* Reduced from 0.5rem */
  line-height: 1.4;
}

.container {
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 1rem;
}

/* Glass Morphism Effects */
.glass-morphism {
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(6px);
  border: 1px solid rgba(0, 0, 0, 0.04);
}

.dark-glass {
  background: rgba(243, 244, 246, 0.7); /* gray-100 */
  backdrop-filter: blur(6px);
  border: 1px solid rgba(0, 0, 0, 0.04);
}

/* Quick Guide Styles */
.guide-container {
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(6px);
  border: 1px solid rgba(0, 0, 0, 0.04);
  border-radius: 0.75rem;
  padding: 0.75rem;
  margin-bottom: 0.75rem;
  box-shadow: 0 4px 16px 0 rgba(59, 130, 246, 0.08);
}

.guide-header {
  display: flex;
  align-items: center;
  justify-content: flex-start;
  margin-bottom: 0.5rem;
}

.guide-header h2 {
  font-size: 1rem;
  font-weight: 600;
  color: #18181b;
  margin-left: 0.5rem;
}

.guide-steps {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 0.5rem;
}

.guide-step {
  background: rgba(243, 244, 246, 0.7);
  backdrop-filter: blur(6px);
  border: 1px solid rgba(0, 0, 0, 0.04);
  border-radius: 0.75rem;
  padding: 0.5rem;
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.step-number {
  width: 1.5rem;
  height: 1.5rem;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 0.5rem;
  font-weight: bold;
  font-size: 0.75rem;
  color: #fff;
  flex-shrink: 0;
}

.step-number.purple {
  background-color: #3B82F6; /* primary */
}

.step-number.blue {
  background-color: #6366F1; /* secondary */
}

.step-number.green {
  background-color: #10B981; /* accent */
}

.step-number.red {
  background-color: #EF4444; /* danger */
}

.step-text {
  font-size: 0.75rem;
  color: #374151;
  text-align: center;
}

/* Main Content Panels Layout */
.main-panels {
  display: flex;
  gap: 0.5rem; /* Reduced from 0.75rem */
  align-items: stretch;
  max-width: 100vw;
  overflow-x: auto;
}

.panel {
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(6px);
  border: 1px solid rgba(0, 0, 0, 0.04);
  border-radius: 0.75rem;
  padding: 0.5rem; /* Reduced from 0.75rem */
  box-shadow: 0 4px 16px 0 rgba(59, 130, 246, 0.08);
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.panel:hover {
  transform: translateY(-0.25rem);
  box-shadow: 0 1.25rem 2.5rem rgba(59, 130, 246, 0.08);
}

.experiment-panel {
  flex: 4; /* Increased from 3 to take more space */
  display: flex;
  flex-direction: column;
  gap: 0.15rem; /* Reduced from 0.25rem */
  min-height: 400px;
}

.steps-panel {
  flex: 1;
  min-width: 180px; /* Reduced from 220px */
  max-width: 200px; /* Added max-width to keep it narrow */
  background: rgba(243, 244, 246, 0.7);
  backdrop-filter: blur(6px);
  border: 1px solid rgba(0, 0, 0, 0.04);
}

.panel-title {
  font-size: 1rem;
  font-weight: 600;
  color: #18181b;
  margin-bottom: 0.75rem;
  display: flex;
  align-items: center;
}

.panel-title svg {
  width: 1rem;
  height: 1rem;
  margin-right: 0.5rem;
}

/* Controls styles */
.controls-container {
  margin-bottom: 0.75rem;
}

.controls-title {
  font-size: 0.875rem;
  font-weight: 600;
  color: #18181b;
  margin-bottom: 0.5rem;
}

.horizontal-controls {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.button {
  color: white;
  border: none;
  box-shadow: 0 0.125rem 0.5rem rgba(59, 130, 246, 0.06);
  transition: all 0.2s ease;
  font-weight: 500;
  font-size: 0.875rem;
  font-family: 'Inter', system-ui, sans-serif;
  padding: 0.75rem 1rem;
  min-width: 140px;
  min-height: 2.5rem;
  border-radius: 0.9rem;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  background: linear-gradient(135deg, #3B82F6, #2563EB);
}

.button:hover {
  filter: brightness(0.95);
  box-shadow: 0 0.25rem 1rem rgba(59, 130, 246, 0.10);
  transform: scale(1.05);
}

.button:active {
  filter: brightness(0.90);
  transform: scale(0.95);
}

.button svg {
  width: 1rem;
  height: 1rem;
}

/* Disabled button styles */
.button:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  pointer-events: none;
}

/* Toggle Switch for Reject Path */
.toggle-switch-container {
  display: flex;
  align-items: center;
  gap: 6px;
}

.toggle-switch {
  position: relative;
  appearance: none;
  width: 36px;
  height: 18px;
  background: #e5e7eb;
  border-radius: 10px;
  cursor: pointer;
  transition: all 0.3s;
}

.toggle-switch:checked {
  background: #3B82F6; /* Changed to match exp9/new */
}

.toggle-switch:before {
  content: '';
  position: absolute;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: white;
  top: 2px;
  left: 2px;
  transition: all 0.3s;
}

.toggle-switch:checked:before {
  left: 20px;
}

.toggle-label {
  font-size: 0.75rem;
  font-weight: 500;
  color: #6b7280; /* gray-500 */
  cursor: pointer;
}

/* NDTM Description Styles */
.ndtm-description {
  margin-bottom: 0.375rem;
  padding: 0.5rem;
  background: linear-gradient(to right, rgba(59, 130, 246, 0.1), rgba(99, 102, 241, 0.1));
  border-radius: 0.75rem;
  border: 1px solid rgba(229, 231, 235, 1);
}

.ndtm-description span {
  color: #18181b;
  font-weight: 500;
  font-size: 0.875rem;
}

/* Input String Container */
.input-string-container {
  margin-bottom: 0.375rem;
}

.input-string-label {
  font-size: 0.75rem;
  font-weight: 600;
  color: #6b7280;
  margin-bottom: 0.25rem;
  text-align: left;
}

#input_container {
  background: #F3F4F6;
  border-radius: 0.75rem;
  padding: 0.5rem;
  color: #18181b;
  font-size: 1.125rem;
  text-align: center;
  min-height: 2.2rem;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 100%;
  font-family: 'Inter', system-ui, monospace;
  font-weight: bold;
  letter-spacing: 0.05em;
}

#input_content {
  font-size: 1.125rem;
  font-weight: bold;
  letter-spacing: 0.05em;
}

/* Input String Highlighted Container */
.input-string-highlighted-container {
  background: linear-gradient(135deg, #f8f9fa, #e9ecef);
  border: 2px solid #6c757d;
  border-radius: 8px;
  padding: 8px 12px;
  margin: 5px 0;
  box-shadow: 0 2px 8px rgba(108, 117, 125, 0.2);
  display: flex;
  align-items: center;
  gap: 12px;
}

.input-string-highlighted-container .input-string-label {
  font-weight: bold;
  color: #495057;
  margin-bottom: 0;
  font-size: 14px;
  flex-shrink: 0;
}

.input-string-highlighted-container #input_container_shared {
  background: white;
  border: 1px solid #6c757d;
  border-radius: 5px;
  padding: 6px 10px;
  font-family: 'Courier New', monospace;
  font-size: 16px;
  font-weight: bold;
  text-align: center;
  min-height: 20px;
  box-shadow: inset 0 1px 3px rgba(0, 0, 0, 0.1);
  flex: 1;
}

/* Transition Table Styles */
.transition-table-container {
  margin-bottom: 0.375rem;
  background: #F3F4F6;
  border-radius: 0.75rem;
  padding: 0.75rem;
  backdrop-filter: blur(6px);
  overflow-x: auto;
}

.transition-table-header {
  margin-bottom: 0.75rem;
}

.transition-table-title {
  font-size: 0.75rem;
  font-weight: 600;
  color: #6b7280;
  margin-bottom: 0.375rem;
  display: flex;
  align-items: center;
  gap: 0.375rem;
}

.transition-table-instruction {
  font-size: 0.875rem;
  color: #6B7280;
  line-height: 1.25rem;
  margin: 0;
}

#transition_table_container {
  overflow-x: auto;
  max-width: 100%;
}

#transition_table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.875rem;
  font-family: 'Inter', system-ui, sans-serif;
  margin: 0;
}

#transition_table th,
#transition_table td {
  border: 1px solid rgba(0, 0, 0, 0.15);
  padding: 0.5rem;
  text-align: center;
  color: #18181b;
}

#transition_table th {
  background-color: rgba(59, 130, 246, 0.1);
  font-weight: 600;
  color: #18181b;
}

#transition_table tr:nth-child(even) {
  background-color: rgba(59, 130, 246, 0.05);
}

#transition_table tr:hover {
  background-color: rgba(59, 130, 246, 0.08);
}

/* Easy Mode Transition Table Buttons */
/* Easy Mode Transition Table Cells */
.easy-mode .transition-table-container #transition_table td,
.transition-table-container.easy-mode #transition_table td,
.experiment-panel.easy-mode #transition_table td {
  position: relative;
  padding: 0.5rem;
  vertical-align: middle;
}

.easy-mode .transition-table-container #transition_table td:not(:first-child),
.transition-table-container.easy-mode #transition_table td:not(:first-child),
.experiment-panel.easy-mode #transition_table td:not(:first-child) {
  padding: 0.25rem;
}

/* Easy Mode Transition Table Buttons - More subtle styling */
.easy-mode .transition-table-container #transition_table td button,
.transition-table-container.easy-mode #transition_table td button,
.experiment-panel.easy-mode #transition_table td button {
  background: transparent !important;
  border: 1px solid transparent !important;
  color: inherit !important;
  font-size: 0.875rem !important;
  font-family: inherit !important;
  font-weight: normal !important;
  padding: 0.25rem 0.5rem !important;
  margin: 0.1rem !important;
  cursor: pointer !important;
  transition: all 0.2s ease !important;
  border-radius: 4px !important;
  display: inline-block !important;
  min-width: auto !important;
  box-shadow: none !important;
}

.easy-mode .transition-table-container #transition_table td button:disabled,
.transition-table-container.easy-mode #transition_table td button:disabled,
.experiment-panel.easy-mode #transition_table td button:disabled {
  cursor: not-allowed !important;
  opacity: 0.6 !important;
  background: transparent !important;
  color: #9ca3af !important;
  border-color: transparent !important;
}

.easy-mode .transition-table-container #transition_table td button.clickable,
.transition-table-container.easy-mode #transition_table td button.clickable,
.experiment-panel.easy-mode #transition_table td button.clickable {
  background: rgba(16, 185, 129, 0.1) !important;
  color: #059669 !important;
  border-color: rgba(16, 185, 129, 0.3) !important;
  font-weight: 500 !important;
}

.easy-mode .transition-table-container #transition_table td button.clickable:hover,
.transition-table-container.easy-mode #transition_table td button.clickable:hover,
.experiment-panel.easy-mode #transition_table td button.clickable:hover {
  background: rgba(16, 185, 129, 0.2) !important;
  border-color: rgba(16, 185, 129, 0.5) !important;
  transform: none !important;
}

.easy-mode .transition-table-container #transition_table td button.correct-choice,
.transition-table-container.easy-mode #transition_table td button.correct-choice,
.experiment-panel.easy-mode #transition_table td button.correct-choice {
  background: rgba(59, 130, 246, 0.15) !important;
  color: #2563eb !important;
  border-color: rgba(59, 130, 246, 0.4) !important;
  font-weight: 500 !important;
}

/* Remove heavy animations and effects for table buttons */
/* Additional button states for better interaction feedback */
.transition-table.easy-mode #transition_table td button:active {
  transform: none;
  box-shadow: none;
}

.transition-table.easy-mode #transition_table td button:focus {
  outline: 1px solid rgba(59, 130, 246, 0.5);
  outline-offset: 1px;
}

.transition-table.easy-mode #transition_table td button.clickable:active {
  transform: none;
  background: rgba(16, 185, 129, 0.25) !important;
}

/* Subtle pulse for clickable buttons only */
@keyframes subtle-pulse {
  0%, 100% {
    border-color: rgba(16, 185, 129, 0.3);
  }
  50% {
    border-color: rgba(16, 185, 129, 0.5);
  }
}

.easy-mode #transition_table td button.clickable {
  animation: subtle-pulse 2s infinite;
}

/* Remove empty cell styling that breaks table appearance */

/* NDTM Visualization */
.ndtm-visualization-container {
  margin-bottom: 0.375rem;
  background: #F3F4F6;
  border-radius: 0.75rem;
  padding: 0.5rem;
  backdrop-filter: blur(6px);
}

.ndtm-visualization {
  display: flex;
  justify-content: center;
  align-items: center;
  border-radius: 0.75rem;
  padding: 0.25rem;
  width: fit-content;
  margin: 0 auto;
  max-width: 100%;
  overflow-x: auto;
  background: #F3F4F6;
}

.visualization-label {
  font-size: 0.75rem;
  font-weight: 600;
  color: #6b7280;
  margin-bottom: 0.1rem;
  text-align: left;
  padding-left: 0.25rem;
}

/* Steps Panel */
.steps-panel {
  display: flex;
  flex-direction: column;
}

.panel-title {
  font-size: 1rem;
  font-weight: 600;
  color: #18181b;
  margin-bottom: 0.75rem;
  display: flex;
  align-items: center;
}

.trace-container {
  background: rgba(243, 244, 246, 0.7);
  backdrop-filter: blur(6px);
  border: 1px solid rgba(0, 0, 0, 0.04);
  border-radius: 12px;
  padding: 15px;
  overflow-y: auto;
  height: auto;
  max-height: 800px;
  min-height: 180px;
  display: flex;
  flex-direction: column;
}

#stack_list {
  list-style-type: none;
  padding: 0;
  margin: 0;
  flex: 1;
  display: flex;
  flex-direction: column; /* Normal order since we prepend items */
}

#stack_list li {
  padding: 8px 10px;
  margin-bottom: 6px;
  background: rgba(255, 255, 255, 0.6);
  border: 1px solid rgba(124, 58, 237, 0.15);
  border-radius: 6px;
  color: #2d1e4a;
  font-size: 0.75rem; /* Smaller font size */
  font-family: monospace;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.05);
  transition: all 0.2s ease;
}

#stack_list li:last-child {
  margin-bottom: 0;
}

#stack_list li:first-child {
  /* Highlight the most recent step (first item) */
  background: rgba(59, 130, 246, 0.08);
  border: 1px solid rgba(59, 130, 246, 0.25);
  box-shadow: 0 2px 8px rgba(59, 130, 246, 0.1);
  font-weight: 500;
  color: #1e40af;
}

#stack_list li.active {
  background: rgba(59, 130, 246, 0.12);
  border: 1px solid rgba(59, 130, 246, 0.3);
  box-shadow: 0 2px 8px rgba(59, 130, 246, 0.15);
  font-weight: 500;
  color: #1e40af;
}

/* Apply same styling to both left and right stack lists */
#stack_list_left,
#stack_list_right {
  list-style-type: none;
  padding: 0;
  margin: 0;
  flex: 1;
  display: flex;
  flex-direction: column; /* Normal order since we prepend items */
}

#stack_list_left li,
#stack_list_right li {
  padding: 8px 10px;
  margin-bottom: 6px;
  background: rgba(255, 255, 255, 0.6);
  border: 1px solid rgba(124, 58, 237, 0.15);
  border-radius: 6px;
  color: #2d1e4a;
  font-size: 0.75rem; /* Smaller font size */
  font-family: monospace;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.05);
  transition: all 0.2s ease;
}

#stack_list_left li:last-child,
#stack_list_right li:last-child {
  margin-bottom: 0;
}

#stack_list_left li:first-child,
#stack_list_right li:first-child {
  /* Highlight the most recent step (first item) */
  background: rgba(59, 130, 246, 0.08);
  border: 1px solid rgba(59, 130, 246, 0.25);
  box-shadow: 0 2px 8px rgba(59, 130, 246, 0.1);
  font-weight: 500;
  color: #1e40af;
}

#stack_list_left li.active,
#stack_list_right li.active {
  background: rgba(59, 130, 246, 0.12);
  border: 1px solid rgba(59, 130, 246, 0.3);
  box-shadow: 0 2px 8px rgba(59, 130, 246, 0.15);
  font-weight: 500;
  color: #1e40af;
}

/* Parallel Simulations Styles */
.parallel-simulations-container {
  display: flex;
  gap: 0.75rem; /* Reduced from 1rem */
  margin-top: 0.75rem; /* Reduced from 1rem */
  transform: scale(0.85); /* Scale down to 85% */
  transform-origin: top center;
}

.simulation-column {
  flex: 1;
  background: rgba(243, 244, 246, 0.7);
  backdrop-filter: blur(6px);
  border: 1px solid rgba(0, 0, 0, 0.04);
  border-radius: 0.5rem; /* Reduced from 0.75rem */
  padding: 0.75rem; /* Reduced from 1rem */
}

.simulation-type-container {
  margin-bottom: 1rem;
  text-align: center;
}

.simulation-type {
  display: inline-block;
  padding: 0.5rem 1rem;
  background: rgba(156, 163, 175, 0.5);
  border-radius: 0.5rem;
  font-weight: 600;
  font-size: 0.875rem;
  transition: all 0.3s ease;
}

.simulation-type.active-simulation {
  background: #3B82F6;
  color: white;
  box-shadow: 0 2px 8px rgba(59, 130, 246, 0.3);
}

.tape-container {
  margin-bottom: 1rem;
}

.tape-label {
  font-weight: 600;
  margin-bottom: 0.5rem;
  color: #374151;
  font-size: 0.875rem;
}

/* Current Turn Indicator */
.current-turn-container {
  margin: 1rem 0;
  text-align: center;
}

.turn-indicator {
  display: inline-block;
  padding: 0.75rem 1.5rem;
  background: linear-gradient(135deg, #3B82F6, #6366F1);
  color: white;
  border-radius: 0.75rem;
  font-weight: 600;
  font-size: 1rem;
  box-shadow: 0 4px 16px rgba(59, 130, 246, 0.3);
  animation: pulse 2s infinite;
}

@keyframes pulse {
  0%, 100% {
    box-shadow: 0 4px 16px rgba(59, 130, 246, 0.3);
  }
  50% {
    box-shadow: 0 6px 20px rgba(59, 130, 246, 0.5);
  }
}

#current_turn_side {
  font-weight: 700;
  text-decoration: underline;
}

/* Shared Input Container */
.shared-input-container {
  margin: 1rem 0;
  text-align: center;
}

.input-string-label {
  font-weight: 600;
  margin-bottom: 0.5rem;
  color: #374151;
  font-size: 0.875rem;
}

/* Steps Panel Modifications for Parallel Layout */
.steps-panel-left,
.steps-panel-right {
  width: 180px; /* Reduced from 200px */
  min-width: 180px; /* Reduced from 200px */
  max-width: 180px; /* Added to enforce narrower width */
}

.steps-panel-left .panel-title {
  background: rgba(16, 185, 129, 0.1);
  color: #059669;
  padding: 0.5rem;
  border-radius: 0.5rem;
  font-weight: 500;
  border: 1px solid rgba(16, 185, 129, 0.2);
}

.steps-panel-right .panel-title {
  background: rgba(239, 68, 68, 0.1);
  color: #dc2626;
  padding: 0.5rem;
  border-radius: 0.5rem;
  font-weight: 500;
  border: 1px solid rgba(239, 68, 68, 0.2);
}

/* Section Title Styling */
.section-title {
  font-weight: 600;
  margin-bottom: 0.75rem;
  color: #374151;
  font-size: 1rem;
  text-align: center;
}

/* Manual Controls Styling */
.manual-controls-container {
  margin: 0.5rem 0; /* Reduced from 1rem 0 */
  background: rgba(243, 244, 246, 0.7);
  backdrop-filter: blur(6px);
  border: 1px solid rgba(0, 0, 0, 0.04);
  border-radius: 0.75rem;
  padding: 0.75rem; /* Reduced from 1rem */
}

.manual-controls-title {
  font-weight: 600;
  margin-bottom: 0.75rem;
  color: #374151;
  font-size: 0.875rem;
  text-align: center;
}

.manual-controls {
  display: flex;
  gap: 1rem;
  align-items: end;
  justify-content: center;
  flex-wrap: wrap;
}

.control-group {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
  min-width: 120px;
}

.control-group label {
  font-size: 0.75rem;
  font-weight: 500;
  color: #6B7280;
}

.control-select {
  padding: 0.5rem;
  border: 1px solid #D1D5DB;
  border-radius: 0.5rem;
  background: white;
  font-size: 0.875rem;
  color: #374151;
  cursor: pointer;
  transition: all 0.2s ease;
}

.control-select:focus {
  outline: none;
  border-color: #3B82F6;
  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

.control-select:hover {
  border-color: #9CA3AF;
}

/* Parallel Simulations Styles */
.parallel-simulations-container {
  display: flex;
  gap: 0.4rem; /* Reduced from 0.5rem */
  margin-top: 0.4rem; /* Reduced from 0.5rem */
  transform: scale(1.0); /* Increased from 0.9 to full size */
  transform-origin: top center;
  margin-bottom: 0px; /* No negative margin needed at full scale */
}

.simulation-column {
  flex: 1;
  background: rgba(243, 244, 246, 0.7);
  backdrop-filter: blur(6px);
  border: 1px solid rgba(0, 0, 0, 0.04);
  border-radius: 0.75rem;
  padding: 0.75rem; /* Reduced from 1rem */
  min-height: 250px; /* Reduced from 300px */
}

.ndtm-visualization {
  display: flex;
  gap: 0.5rem;
  justify-content: center;
  align-items: center;
  margin-top: 0.5rem;
  overflow: hidden; /* Ensure content fits within container */
}

.ndtm-visualization svg {
  max-width: 100%;
  height: auto;
  border: 1px solid #e5e7eb;
  border-radius: 0.5rem;
  background: white;
}

/* Increase canvas sizes for better tape visibility */
#canvas1_left, #canvas1_right {
  width: 500px !important; /* Reduced from 600px */
  height: 180px !important; /* Reduced from 220px */
}

#canvas2_left, #canvas2_right {
  width: 100px !important; /* Reduced from 120px */
  height: 180px !important; /* Reduced from 220px */
}

/* Active path highlighting - similar to exp7/new */
.simulation-column.active-path {
  background: rgba(59, 130, 246, 0.08);
  border: 2px solid #3b82f6;
  box-shadow: 0 4px 16px rgba(59, 130, 246, 0.15);
  transition: all 0.3s ease;
}

.simulation-column.active-path .tape-container {
  background: rgba(255, 255, 255, 0.8);
  border-radius: 8px;
  padding: 12px;
  box-shadow: 0 2px 8px rgba(59, 130, 246, 0.1);
}

/* Mode Tabs Styling */
.mode-tabs-container {
  margin-bottom: 0.75rem;
}

.mode-tabs {
  display: flex;
  gap: 0.25rem;
  background: rgba(243, 244, 246, 0.7);
  backdrop-filter: blur(6px);
  border: 1px solid rgba(0, 0, 0, 0.04);
  border-radius: 0.75rem;
  padding: 0.25rem;
}

.mode-tab {
  flex: 1;
  padding: 0.5rem 1rem;
  border: none;
  border-radius: 0.5rem;
  background: transparent;
  color: #6B7280;
  font-weight: 500;
  font-size: 0.875rem;
  cursor: pointer;
  transition: all 0.2s ease;
}

.mode-tab:hover {
  background: rgba(255, 255, 255, 0.5);
  color: #374151;
}

.mode-tab.active {
  background: #3B82F6;
  color: white;
  box-shadow: 0 2px 8px rgba(59, 130, 246, 0.3);
}

.mode-tab.active:hover {
  background: #2563EB;
}

@media (max-width: 768px) {
  .main-panels {
    flex-direction: column;
  }
  
  .guide-steps {
    grid-template-columns: 1fr;
  }
  
  .horizontal-controls {
    flex-direction: column;
    align-items: flex-start;
  }
  
  .button {
    width: 100%;
  }
  
  .ndtm-visualization {
    flex-direction: column;
  }
  
  .manual-controls {
    flex-direction: column;
    align-items: center;
  }
  
  .control-group {
    width: 100%;
    max-width: 200px;
  }
}

/* Button Color Definitions */
.button.green {
  background: #10B981;
  color: #fff;
  border: none;
}

.button.green:hover {
  background: linear-gradient(135deg, #059669, #047857);
}

.button.red {
  background: #EF4444;
  color: #fff;
  border: none;
}

.button.red:hover {
  background: linear-gradient(135deg, #dc2626, #b91c1c);
}

.button.blue {
  background: #6366F1;
  color: #fff;
  border: none;
}

.button.blue:hover {
  background: linear-gradient(135deg, #2563eb, #1d4ed8);
}

.button.purple {
  background: #3B82F6;
  color: #fff;
  border: none;
}

.button.purple:hover {
  background: linear-gradient(135deg, #2563eb, #1d4ed8);
}

.button.gray {
  background: linear-gradient(135deg, #6b7280, #4b5563);
  color: white;
  border: 1px solid #374151;
}

.button.gray:hover {
  background: linear-gradient(135deg, #4b5563, #374151);
}

/* Mobile responsiveness updates for parallel layout */
@media (max-width: 1024px) {
  .parallel-simulations-container {
    flex-direction: column;
  }
  
  .simulation-column {
    margin-bottom: 1rem;
  }
  
  .steps-panel-left,
  .steps-panel-right {
    width: 100%;
    min-width: unset;
    order: 3;
  }
  
  .experiment-panel {
    order: 1;
  }
}

/* Hide hard mode controls in easy mode */
.easy-mode #hard_mode_controls,
.experiment-panel.easy-mode #hard_mode_controls {
  display: none !important;
}