/* ── profpi / ODE & Phase Portrait Explorer ── */
/* Extends home.css: same tokens, same card/button language. Every var()
   below carries a fallback so this page still renders correctly even if
   css/tokens.css hasn't loaded — but the fallback never wins once the
   real token is defined, so it can't fight your site's actual theme. */

:root {
  /* Brand accents used elsewhere on the site (hero gradient, CTAs) */
  --op-accent-2: var(--accent-secondary, #06b6d4);
  --op-success: var(--success, #10b981);
  --op-danger: var(--danger, #ef4444);
  --op-neutral: var(--neutral-accent, #8b5cf6);
}

/* ── Tool page hero (compact version of the homepage hero) ── */
.tool-page-hero {
  max-width: 1140px;
  margin: 0 auto;
  padding: 56px 24px 8px;
  text-align: left;
}

.tool-page-hero h1 {
  font-size: clamp(1.8rem, 3.4vw, 2.6rem);
  font-weight: 800;
  letter-spacing: -0.02em;
  line-height: 1.12;
  margin-bottom: 14px;
  color: var(--text-main, #0f172a);
}

.tool-hero-sub {
  font-size: 1rem;
  color: var(--text-muted, #64748b);
  line-height: 1.65;
  max-width: 640px;
}

.tool-hero-sub code {
  background: var(--card-active, #eef2ff);
  color: var(--accent, #6366f1);
  padding: 1px 6px;
  border-radius: 4px;
  font-size: 0.88em;
}

/* ── Explorer layout ── */
.explorer {
  max-width: 1140px;
  margin: 0 auto;
  padding: 28px 24px 56px;
  display: grid;
  grid-template-columns: 320px 1fr;
  gap: 24px;
  align-items: stretch;
}

/* ── Control panel ── */
.control-panel {
  background: var(--card-bg, #ffffff);
  border: 1px solid var(--border-color, #e2e8f0);
  border-radius: var(--radius-lg, 16px);
  padding: 22px;
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.field-group {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.field-label {
  font-size: 0.82rem;
  font-weight: 700;
  color: var(--text-main, #0f172a);
  letter-spacing: -0.01em;
}

.hint-text {
  font-size: 0.8rem;
  color: var(--text-muted, #64748b);
  line-height: 1.5;
  margin: 0;
}

/* Mode toggle (segmented control) */
.mode-toggle {
  display: flex;
  background: var(--card-active, #eef2ff);
  border-radius: var(--radius-md, 10px);
  padding: 3px;
  gap: 3px;
}

.mode-btn {
  flex: 1;
  border: none;
  background: transparent;
  color: var(--text-muted, #64748b);
  font-size: 0.82rem;
  font-weight: 600;
  padding: 8px 6px;
  border-radius: calc(var(--radius-md, 10px) - 3px);
  cursor: pointer;
  transition: background 0.15s, color 0.15s, box-shadow 0.15s;
}

.mode-btn:hover {
  color: var(--text-main, #0f172a);
}

.mode-btn.is-active {
  background: var(--card-bg, #ffffff);
  color: var(--accent, #6366f1);
  box-shadow: 0 1px 3px rgba(15, 23, 42, 0.12);
}

/* Expression inputs */
.expr-input {
  width: 100%;
  font-family: 'SFMono-Regular', ui-monospace, Menlo, Consolas, monospace;
  font-size: 0.92rem;
  color: var(--text-main, #0f172a);
  background: var(--card-bg, #ffffff);
  border: 1px solid var(--border-color, #e2e8f0);
  border-radius: var(--radius-md, 10px);
  padding: 10px 12px;
  box-sizing: border-box;
  transition: border-color 0.15s, box-shadow 0.15s;
}

.expr-input:focus-visible {
  outline: none;
  border-color: var(--accent, #6366f1);
  box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.18);
}

.expr-input.has-error {
  border-color: var(--op-danger);
}

.preset-row {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.preset-chip {
  font-size: 0.74rem;
  font-weight: 600;
  color: var(--text-muted, #64748b);
  background: var(--card-active, #eef2ff);
  border: 1px solid transparent;
  border-radius: 999px;
  padding: 5px 10px;
  cursor: pointer;
  transition: color 0.15s, border-color 0.15s;
}

.preset-chip:hover {
  color: var(--accent, #6366f1);
  border-color: var(--accent, #6366f1);
}

/* Bounds grid */
.bounds-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px;
}

.bound-field {
  display: flex;
  flex-direction: column;
  gap: 4px;
  font-size: 0.74rem;
  font-weight: 600;
  color: var(--text-muted, #64748b);
}

.bound-field input {
  font-size: 0.86rem;
  color: var(--text-main, #0f172a);
  background: var(--card-bg, #ffffff);
  border: 1px solid var(--border-color, #e2e8f0);
  border-radius: 8px;
  padding: 7px 8px;
  box-sizing: border-box;
  width: 100%;
}

.bound-field input:focus-visible {
  outline: none;
  border-color: var(--accent, #6366f1);
  box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.18);
}

/* Range slider */
input[type="range"] {
  width: 100%;
  accent-color: var(--accent, #6366f1);
}

/* Checkbox row */
.checkbox-field {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.86rem;
  font-weight: 600;
  color: var(--text-main, #0f172a);
  cursor: pointer;
}

.checkbox-field input {
  accent-color: var(--accent, #6366f1);
  width: 16px;
  height: 16px;
}

/* Buttons */
.btn-primary {
  width: 100%;
  background: var(--accent, #6366f1);
  color: #fff;
  border: none;
  font-weight: 700;
  font-size: 0.92rem;
  padding: 11px 16px;
  border-radius: var(--radius-md, 10px);
  cursor: pointer;
  transition: background 0.2s, transform 0.15s;
}

.btn-primary:hover {
  background: var(--accent-hover, #4f46e5);
  transform: translateY(-1px);
}

.btn-secondary {
  width: 100%;
  background: transparent;
  color: var(--text-main, #0f172a);
  border: 1px solid var(--border-color, #e2e8f0);
  font-weight: 600;
  font-size: 0.86rem;
  padding: 9px 16px;
  border-radius: var(--radius-md, 10px);
  cursor: pointer;
  transition: border-color 0.15s, color 0.15s;
}

.btn-secondary:hover {
  border-color: var(--accent, #6366f1);
  color: var(--accent, #6366f1);
}

/* Error banner */
.error-banner {
  font-size: 0.82rem;
  line-height: 1.5;
  color: #991b1b;
  background: #fef2f2;
  border: 1px solid #fecaca;
  border-radius: var(--radius-md, 10px);
  padding: 10px 12px;
}

html[data-theme="dark"] .error-banner {
  color: #fca5a5;
  background: rgba(239, 68, 68, 0.12);
  border-color: rgba(239, 68, 68, 0.35);
}

/* ── Canvas panel ── */
.canvas-panel {
  display: flex;
  height: 100%;
  flex-direction: column;
  gap: 20px;
}

.canvas-wrap {
  position: relative;
  background: var(--card-bg, #ffffff);
  border: 1px solid var(--border-color, #e2e8f0);
  border-radius: var(--radius-lg, 16px);
  box-shadow: var(--shadow-lg, 0 20px 40px -12px rgba(15, 23, 42, 0.15));
  padding: 10px;
  max-width: 600px;
  flex: 1;
  min-height: 0;
  margin: 0 auto;
}

#plotCanvas {
  width: 100%;
  height: 100%;
  min-height: 400px;
  border-radius: calc(var(--radius-lg, 16px) - 6px);
  display: block;
  cursor: crosshair;
  touch-action: none;
}

.canvas-legend {
  position: absolute;
  bottom: 20px;
  left: 20px;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  pointer-events: none;
}

.legend-chip {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 0.72rem;
  font-weight: 600;
  color: var(--text-muted, #64748b);
  background: var(--card-bg, #ffffff);
  border: 1px solid var(--border-color, #e2e8f0);
  border-radius: 999px;
  padding: 4px 10px;
}

.legend-swatch {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  flex-shrink: 0;
}

/* Equilibria panel */
.equilibria-panel {
  background: var(--card-bg, #ffffff);
  border: 1px solid var(--border-color, #e2e8f0);
  border-radius: var(--radius-lg, 16px);
  padding: 20px 22px;
}

.equilibria-panel h2 {
  font-size: 0.95rem;
  font-weight: 700;
  margin-bottom: 12px;
  color: var(--text-main, #0f172a);
}

.equilibria-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 10px;
}

.equilibria-list li {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  font-size: 0.82rem;
  color: var(--text-muted, #64748b);
  background: var(--card-active, #eef2ff);
  border-radius: var(--radius-md, 10px);
  padding: 10px 12px;
}

.equilibria-list .eq-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  margin-top: 4px;
  flex-shrink: 0;
}

.equilibria-list strong {
  color: var(--text-main, #0f172a);
  display: block;
  font-size: 0.84rem;
}

/* ── Trust / notes strip ── */
.tool-notes {
  max-width: 1140px;
  margin: 0 auto;
  padding: 0 24px 64px;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.tool-note-card {
  background: var(--card-bg, #ffffff);
  border: 1px solid var(--border-color, #e2e8f0);
  border-radius: var(--radius-lg, 16px);
  padding: 20px;
}

.tool-note-card h3 {
  font-size: 0.94rem;
  font-weight: 700;
  color: var(--text-main, #0f172a);
  margin-bottom: 6px;
}

.tool-note-card p {
  font-size: 0.84rem;
  color: var(--text-muted, #64748b);
  line-height: 1.55;
  margin: 0;
}

.is-hidden {
  display: none !important;
}

/* -- Responsive -- */
@media (max-width: 900px) {
  .explorer {
    grid-template-columns: 1fr;
  }

  .control-panel {
    position: static;
  }

  /* Reset stretch — no parent height in single-column layout */
  .canvas-panel {
    height: auto;
  }

  .canvas-wrap {
    flex: none;
    min-height: 420px;
    max-width: 100%;
    margin: 0;
  }

  #plotCanvas {
    min-height: 400px;
  }

  .tool-notes {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 480px) {
  .tool-page-hero {
    padding: 40px 20px 8px;
  }

  .explorer {
    padding: 24px 16px 48px;
  }

  .canvas-wrap {
    min-height: 360px;
  }

  #plotCanvas {
    min-height: 340px;
  }

  .bounds-grid {
    grid-template-columns: 1fr 1fr;
  }
}