:root {
  --navy: #2c3e50;
  --softgray: #e9ecef;
  --teal: #1abc9c;
  --gold: #f1c40f;
  --slate: #556366;
  --coral: #e74c3c;
  --white: #ffffff;
  --gray-100: #f7fafc;
  --gray-200: #edf2f7;
  --gray-300: #e2e8f0;
  --max-width: 1120px;
  --container-pad: 16px;
  --radius: 10px;
  --shadow-sm: 0 6px 18px rgba(0, 0, 0, 0.06);
  --shadow-xs: 0 1px 2px rgba(0, 0, 0, 0.06);
}

* { box-sizing: border-box; }

html, body { height: 100%; }

body {
  margin: 0;
  font-family: "Montserrat", system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial;
  color: var(--navy);
  background: linear-gradient(135deg, #ecf0f1 0%, #d6dbdf 100%);
  padding: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  gap: 18px;
  padding: 18px;
}

li { line-height: 2; }

.page-header {
  text-align: center;
  color: var(--navy);
  padding: 1rem;
  position: relative;
}

.header-left { justify-self: start; }

.header-grid {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: 12px;
  padding: 8px 0;
}

.page-title {
  margin: 0;
  justify-self: center;
  font-size: 2rem;
  font-weight: 700;
  font-family: "Montserrat", sans-serif;
}

.header-actions { justify-self: end; }

@media (max-width: 767px) {
  .header-grid {
    grid-template-columns: 1fr;
    grid-auto-flow: row;
    text-align: left;
  }
  .page-title { justify-self: start; }
  .header-actions { justify-self: start; width: 100%; margin-top: 8px; }
}

.cols {
  display: flex;
  flex-direction: column;
  gap: 24px;
}

.experiment-area {
  background: var(--gray-100);
  border-radius: 10px;
  padding: 20px;
  margin-bottom: 24px;
}

.sim-area {
  background: var(--softgray);
  border-radius: 8px;
  padding: 12px;
  position: relative;
  overflow: hidden;
  height: 420px;
}

.sim-area canvas {
  width: 100%;
  height: 100%;
  display: block;
  border-radius: 6px;
}

.sim-area.can-drag { cursor: grab; }
.sim-area.dragging { cursor: grabbing; }

.sim-overlay {
  position: absolute;
  left: 16px;
  top: 16px;
  display: flex;
  gap: 10px;
  pointer-events: none;
}

.overlay-pill {
  padding: 8px 10px;
  border-radius: 999px;
  background: rgba(44, 62, 80, 0.10);
  color: var(--navy);
  font-weight: 700;
  font-size: 14px;
  backdrop-filter: blur(4px);
}

.controls {
  background: white;
  border-radius: 8px;
  padding: 16px;
  box-shadow: var(--shadow-sm);
}

.control-group { margin-bottom: 18px; }

.label {
  display: block;
  margin-bottom: 6px;
  font-size: 14px;
  color: var(--slate);
  font-weight: 600;
}

.range-row {
  display: flex;
  align-items: center;
  gap: 12px;
}

.range { flex: 1; }

.value {
  display: inline-block;
  padding: 6px 8px;
  border-radius: 6px;
  background: rgba(26, 188, 156, 0.12);
  color: var(--teal);
  min-width: 64px;
  text-align: center;
  font-weight: 700;
}

.value.coral {
  background: rgba(231, 76, 60, 0.12);
  color: var(--coral);
}

.select {
  width: 100%;
  padding: 10px 12px;
  border-radius: 8px;
  border: 1px solid var(--softgray);
  background: white;
  color: var(--navy);
  font-weight: 600;
  font-family: inherit;
}

.help-text {
  margin-top: 6px;
  font-size: 12px;
  color: var(--slate);
}

.toggle-row { margin-top: 8px; }

.toggle {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 14px;
  color: var(--slate);
  font-weight: 600;
}

.toggle input { transform: translateY(1px); }

.button-stack {
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin-top: 24px;
}

.btn {
  display: inline-block;
  border-radius: 0.375rem;
  text-decoration: none;
  text-align: center;
  transition: all 0.2s;
  cursor: pointer;
  border: 1px solid transparent;
  width: auto;
  font-size: 16px;
  font-weight: 600;
  padding: 12px 24px;
}

.teal-btn {
  background-color: rgba(26, 188, 156, 0.8);
  color: white;
}
.teal-btn:hover {
  background-color: rgba(26, 188, 156, 0.7);
  transform: translateY(-2px);
}

.gold-btn {
  background-color: rgba(241, 196, 15, 1);
  color: var(--navy);
  opacity: 0.9;
}
.gold-btn:hover {
  background-color: rgba(241, 196, 15, 0.5);
  transform: translateY(-2px);
}

.coral-btn {
  background-color: rgba(231, 76, 60, 0.8);
  color: white;
}
.coral-btn:hover {
  background-color: rgba(231, 76, 60, 0.7);
  transform: translateY(-2px);
}

.navy-btn {
  background-color: rgba(44, 62, 80, 0.8);
  color: white;
}
.navy-btn:hover {
  background-color: rgba(44, 62, 80, 0.7);
  transform: translateY(-2px);
}

.panel {
  margin-top: 24px;
  background: white;
  border-radius: 8px;
  padding: 16px;
  box-shadow: var(--shadow-sm);
}

.panel h3 {
  margin: 0 0 12px 0;
  font-size: 18px;
}

.table-wrap { overflow-x: auto; }

.results-table {
  width: 100%;
  border-collapse: collapse;
  background: white;
  border: 1px solid var(--softgray);
}

.results-table th,
.results-table td {
  border: 1px solid var(--softgray);
  padding: 8px;
  text-align: left;
}

.results-table thead tr { background: var(--softgray); }

.results-table th { font-weight: 700; }

/* Range input styling */
input[type="range"] {
  -webkit-appearance: none;
  appearance: none;
  height: 6px;
  background: transparent;
}

input[type="range"]:focus { outline: none; }

input[type="range"]::-webkit-slider-runnable-track {
  height: 6px;
  background: linear-gradient(90deg, #d0d0d0, #bdbdbd);
  border-radius: 6px;
}

input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: var(--navy);
  margin-top: -6px;
  box-shadow: 0 2px 6px rgba(0,0,0,0.2);
}

input[type="range"]::-moz-range-track {
  height: 6px;
  background: linear-gradient(90deg, #d0d0d0, #bdbdbd);
  border-radius: 6px;
}

input[type="range"]::-moz-range-thumb {
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: var(--navy);
  border: none;
}

a:focus,
button:focus,
input:focus {
  outline: 3px solid rgba(26, 188, 156, 0.18);
  outline-offset: 2px;
}

@media (min-width: 768px) {
  body { padding: 24px; }
  .container { padding: 0; }
  .cols { flex-direction: row; }
  .sim-area { flex: 2; margin-right: 24px; }
  .controls { flex: 1; }
  .page-title { font-size: 32px; }
}