/* ============================================================
   Triangular Number Matrix — Main Stylesheet
   Theme: Deep Space Scientific Instrument
   ============================================================ */

/* ---- Custom Properties ---- */
:root {
  /* Backgrounds — layered depth */
  --bg-void:     #05070e;
  --bg-space:    #080c16;
  --bg-surface:  #0d1220;
  --bg-card:     #111728;
  --bg-elevated: #16203a;
  --bg-hover:    #1b2640;

  /* Borders */
  --border-dim:    #1a2438;
  --border:        #223050;
  --border-bright: #2d4068;

  /* Text */
  --text-bright:    #e4edff;
  --text-primary:   #b8ccec;
  --text-secondary: #6a8bae;
  --text-muted:     #334560;

  /* Cyan — primary interactive */
  --cyan:        #38bff8;
  --cyan-bright: #67d4ff;
  --cyan-glow:   rgba(56, 191, 248, 0.18);
  --cyan-dim:    rgba(56, 191, 248, 0.07);

  /* Gold — mathematical constants */
  --gold:        #e8b740;
  --gold-bright: #f5cc60;
  --gold-glow:   rgba(232, 183, 64, 0.18);
  --gold-dim:    rgba(232, 183, 64, 0.07);

  /* Violet — active/selected state */
  --violet:        #a78bfa;
  --violet-bright: #c4b0ff;
  --violet-glow:   rgba(167, 139, 250, 0.22);
  --violet-dim:    rgba(167, 139, 250, 0.08);

  /* Green — numbers & success */
  --green:        #34d399;
  --green-bright: #5ee8b4;
  --green-glow:   rgba(52, 211, 153, 0.18);
  --green-dim:    rgba(52, 211, 153, 0.07);

  /* Status */
  --red:    #f87171;
  --amber:  #fbbf24;

  /* Typography */
  --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', system-ui, sans-serif;
  --font-mono: 'SF Mono', 'Fira Code', 'Cascadia Code', Consolas, 'Liberation Mono', monospace;

  /* Spacing */
  --radius-sm: 6px;
  --radius:    10px;
  --radius-lg: 16px;

  /* Transitions */
  --ease: cubic-bezier(0.16, 1, 0.3, 1);
}

/* ---- Reset ---- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { font-size: 15px; }

body {
  font-family: var(--font-sans);
  background-color: var(--bg-space);
  color: var(--text-primary);
  min-height: 100vh;
  line-height: 1.6;
  /* Subtle grid pattern — graph paper feel */
  background-image:
    linear-gradient(rgba(56, 191, 248, 0.025) 1px, transparent 1px),
    linear-gradient(90deg, rgba(56, 191, 248, 0.025) 1px, transparent 1px);
  background-size: 48px 48px;
}

/* ============================================================
   HEADER
   ============================================================ */
.app-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(8, 12, 22, 0.92);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-dim);
  box-shadow: 0 4px 32px rgba(0, 0, 0, 0.4);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  max-width: 1600px;
  margin: 0 auto;
  padding: 0 24px;
  height: 58px;
}

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

.logo-triangle {
  flex-shrink: 0;
  filter: drop-shadow(0 0 8px var(--cyan));
}

.logo-text {
  font-size: 1.1rem;
  font-weight: 600;
  letter-spacing: 0.02em;
  color: var(--text-bright);
}

.logo-sub {
  font-size: 0.7rem;
  color: var(--cyan);
  letter-spacing: 0.12em;
  text-transform: uppercase;
  font-weight: 500;
  margin-top: -2px;
}

.header-meta {
  display: flex;
  align-items: center;
  gap: 20px;
  font-size: 0.8rem;
  color: var(--text-muted);
}

.status-dot {
  display: inline-block;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--green);
  box-shadow: 0 0 8px var(--green-glow);
  animation: pulse-dot 2.5s ease-in-out infinite;
}

@keyframes pulse-dot {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.4; }
}

/* ============================================================
   MAIN LAYOUT
   ============================================================ */
.app-main {
  max-width: 1600px;
  margin: 0 auto;
  padding: 24px;
  display: flex;
  flex-direction: column;
  gap: 20px;
}

/* ── Top grid: Calculator (left) | Matrix Constants (right) ─────── */
.top-grid {
  display: grid;
  grid-template-columns: 1fr 420px;
  gap: 20px;
}

/* Result inset inside Calculator panel */
.result-inset {
  border-top: 1px solid var(--border-dim);
}

.result-inset-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 10px 20px;
  border-bottom: 1px solid var(--border-dim);
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: rgba(56, 191, 248, 0.75);
  background: rgba(255, 255, 255, 0.02);
}

/* Full-width triangular number display below top-grid */
.display-panel {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
}

.display-panel .number-display {
  border-radius: 0;
  border: none;
  max-height: 320px;
  margin: 0;
}

/* ============================================================
   PANEL / CARD BASE
   ============================================================ */
.panel {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
}

.panel-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 20px;
  border-bottom: 1px solid var(--border-dim);
  background: rgba(255, 255, 255, 0.02);
}

.panel-title {
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: rgba(56, 191, 248, 0.75);
}

.panel-title-icon {
  margin-right: 8px;
  opacity: 0.9;
}

.panel-subtitle {
  font-size: 0.72rem;
  color: var(--text-secondary);
}

.panel-body {
  padding: 20px;
}

/* ============================================================
   CALCULATOR PANEL
   ============================================================ */

/* ── File mode radio ── */
.file-mode-row {
  display: flex;
  align-items: flex-start;
  flex-wrap: wrap;
  gap: 10px;
  padding: 12px 14px;
  margin-bottom: 16px;
  background: var(--bg-surface);
  border: 1px solid var(--border-dim);
  border-radius: var(--radius);
}

.file-mode-label {
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-muted);
  align-self: center;
  margin-right: 6px;
  flex-shrink: 0;
}

.file-mode-option {
  display: flex;
  align-items: flex-start;
  gap: 8px;
  cursor: pointer;
  padding: 6px 12px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-dim);
  background: var(--bg-card);
  transition: all 0.15s;
  flex: 1;
  min-width: 140px;
}

.file-mode-option:has(input:checked) {
  border-color: var(--cyan);
  background: var(--cyan-dim);
  box-shadow: 0 0 8px var(--cyan-glow);
}

.file-mode-option input[type="radio"] {
  margin-top: 3px;
  accent-color: var(--cyan);
  flex-shrink: 0;
}

.file-mode-text {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.file-mode-name {
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--text-bright);
}

.file-mode-desc {
  font-size: 0.7rem;
  color: var(--text-muted);
}

.file-mode-option:has(input:checked) .file-mode-name {
  color: var(--cyan-bright);
}
.file-mode-option:has(input:checked) .file-mode-desc {
  color: var(--cyan);
  opacity: 0.8;
}

.file-browser {
  margin-bottom: 18px;
}

.file-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.82rem;
}

.file-table th {
  text-align: left;
  color: var(--text-secondary);
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  padding: 6px 10px;
  border-bottom: 1px solid var(--border-dim);
}

.file-table td {
  padding: 7px 10px;
  border-bottom: 1px solid rgba(26, 36, 56, 0.5);
  vertical-align: middle;
}

.file-table tr:last-child td { border-bottom: none; }

.file-table tr:hover td {
  background: var(--bg-hover);
}

.file-table tr.selected td {
  background: var(--cyan-dim);
}

.file-name {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--text-bright);
}

.file-size {
  font-family: var(--font-mono);
  font-size: 0.76rem;
  color: var(--text-secondary);
}

.file-digits {
  font-family: var(--font-mono);
  font-size: 0.76rem;
  color: var(--cyan);
}

.btn-use {
  background: var(--cyan-dim);
  color: var(--cyan);
  border: 1px solid rgba(56, 191, 248, 0.25);
  border-radius: var(--radius-sm);
  padding: 3px 10px;
  font-size: 0.72rem;
  cursor: pointer;
  transition: all 0.15s;
  font-family: var(--font-sans);
}
.btn-use:hover {
  background: var(--cyan-glow);
  border-color: var(--cyan);
  box-shadow: 0 0 8px var(--cyan-glow);
}
.btn-use.active {
  background: var(--cyan);
  color: var(--bg-void);
  font-weight: 700;
}

.btn-gen {
  background: transparent;
  color: var(--cyan);
  border: 1px solid var(--cyan);
  border-radius: var(--radius-sm);
  padding: 2px 7px;
  font-size: 0.68rem;
  cursor: pointer;
  white-space: nowrap;
  font-family: var(--font-sans);
  transition: all 0.15s;
}
.btn-gen:hover:not(.btn-gen-disabled) {
  background: var(--cyan-dim);
  box-shadow: 0 0 6px var(--cyan-glow);
}
.btn-gen-disabled {
  color: var(--text-secondary);
  border-color: var(--border-bright);
  background: rgba(34, 48, 80, 0.25);
  cursor: not-allowed;
}

/* Input preview */
.input-label {
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-primary);
  margin-bottom: 6px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.input-meta {
  font-size: 0.7rem;
  color: var(--text-secondary);
  font-family: var(--font-mono);
  text-transform: none;
  letter-spacing: 0;
}

.input-file-badge {
  font-size: 0.7rem;
  font-family: var(--font-mono);
  text-transform: none;
  letter-spacing: 0;
  white-space: nowrap;
}

.number-textarea {
  width: 100%;
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--green);
  font-family: var(--font-mono);
  font-size: 0.8rem;
  line-height: 1.5;
  padding: 12px 14px;
  resize: vertical;
  min-height: 90px;
  transition: border-color 0.2s, box-shadow 0.2s;
  overflow-wrap: anywhere;
  word-break: break-all;
}

.number-textarea:focus {
  outline: none;
  border-color: var(--cyan);
  box-shadow: 0 0 0 3px var(--cyan-dim), 0 0 12px var(--cyan-glow);
}

.number-textarea::placeholder {
  color: var(--text-muted);
  font-size: 0.75rem;
}

/* Form controls row */
.controls-row {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 12px;
  align-items: end;
  margin-top: 16px;
}

/* Horizontal row: Increment + Method + Calculate */
.calc-bottom-row {
  display: flex;
  gap: 10px;
  align-items: flex-end;
  margin-top: 12px;
}

.calc-bottom-row .btn-calculate {
  width: auto;
  margin-top: 0;
  padding: 10px 16px;
  white-space: nowrap;
  font-size: 0.88rem;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.form-label {
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-primary);
}

.select-control {
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--text-primary);
  font-family: var(--font-sans);
  font-size: 0.85rem;
  padding: 9px 12px;
  cursor: pointer;
  transition: border-color 0.2s;
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='8' viewBox='0 0 12 8'%3E%3Cpath d='M1 1l5 5 5-5' stroke='%236a8bae' stroke-width='1.5' fill='none'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 12px center;
  padding-right: 32px;
}
.select-control:focus {
  outline: none;
  border-color: var(--cyan);
  box-shadow: 0 0 0 3px var(--cyan-dim);
}

.input-control {
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--text-primary);
  font-family: var(--font-mono);
  font-size: 0.85rem;
  padding: 9px 12px;
  width: 100%;
  transition: border-color 0.2s;
}
.input-control:focus {
  outline: none;
  border-color: var(--gold);
  box-shadow: 0 0 0 3px var(--gold-dim);
}

/* Calculate button */
.btn-calculate {
  width: 100%;
  margin-top: 16px;
  padding: 14px 24px;
  background: linear-gradient(135deg, #1a4a7a 0%, #0f2d52 50%, #162140 100%);
  border: 1px solid var(--cyan);
  border-radius: var(--radius);
  color: var(--cyan-bright);
  font-family: var(--font-sans);
  font-size: 0.95rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  cursor: pointer;
  position: relative;
  overflow: hidden;
  transition: all 0.2s var(--ease);
  box-shadow: 0 0 20px rgba(56, 191, 248, 0.1), inset 0 1px 0 rgba(255,255,255,0.05);
}

.btn-calculate::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, var(--cyan-glow), transparent 60%);
  opacity: 0;
  transition: opacity 0.3s;
}

.btn-calculate:hover {
  border-color: var(--cyan-bright);
  box-shadow: 0 0 30px var(--cyan-glow), 0 4px 20px rgba(0,0,0,0.3);
  transform: translateY(-1px);
}
.btn-calculate:hover::before { opacity: 1; }

.btn-calculate:active { transform: translateY(0); }

.btn-calculate.htmx-request {
  opacity: 0.7;
  cursor: wait;
  animation: shimmer 1.5s linear infinite;
}

@keyframes shimmer {
  0% { background-position: -200% center; }
  100% { background-position: 200% center; }
}

.btn-triangle {
  margin-right: 8px;
  font-size: 1rem;
}

/* ============================================================
   CONSTANTS PANEL
   ============================================================ */
.digit-selector {
  display: grid;
  grid-template-columns: repeat(9, 1fr);
  gap: 6px;
  margin-bottom: 18px;
}

.digit-btn {
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--text-secondary);
  font-family: var(--font-mono);
  font-size: 0.85rem;
  font-weight: 600;
  padding: 8px 4px;
  cursor: pointer;
  text-align: center;
  transition: all 0.15s;
}
.digit-btn:hover {
  border-color: var(--gold);
  color: var(--gold);
  background: var(--gold-dim);
}
.digit-btn.active {
  border-color: var(--gold);
  color: var(--bg-void);
  background: var(--gold);
  box-shadow: 0 0 12px var(--gold-glow);
}

/* Number Family label above digit selector */
.constants-section-label {
  font-size: 0.62rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-secondary);
  margin-bottom: 8px;
}

/* Vertical Constants / Digital Root header row above vpc grid */
.constants-meta-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 6px;
}

.vc-col-header {
  font-size: 0.62rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--gold);
}

.dr-col-header {
  font-size: 0.62rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--green);
}

/* VPC grid */
.vpc-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 6px;
  margin-bottom: 14px;
}

.vpc-item {
  background: var(--bg-surface);
  border: 1px solid var(--border-dim);
  border-radius: var(--radius-sm);
  padding: 8px 10px;
  transition: all 0.2s var(--ease);
}

.vpc-label {
  font-size: 0.72rem;
  color: var(--green);
  font-family: var(--font-mono);
  font-weight: 700;
  margin-bottom: 3px;
}

.vpc-value {
  font-family: var(--font-mono);
  font-size: 0.82rem;
  color: var(--gold);
  font-weight: 600;
}

.vpc-item.active {
  border-color: var(--red);
  background: rgba(248, 113, 113, 0.08);
  box-shadow: 0 0 10px rgba(248, 113, 113, 0.22);
  animation: vpc-pulse 0.4s var(--ease);
}
.vpc-item.active .vpc-value { color: var(--red); }

@keyframes vpc-pulse {
  0% { transform: scale(0.97); }
  60% { transform: scale(1.02); }
  100% { transform: scale(1); }
}

/* Patterns row */
.patterns-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px;
  margin-bottom: 10px;
}

.pattern-item {
  background: var(--bg-surface);
  border: 1px solid var(--border-dim);
  border-radius: var(--radius-sm);
  padding: 8px 10px;
}

.pattern-label {
  font-size: 0.65rem;
  color: var(--text-secondary);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  margin-bottom: 3px;
}

.pattern-value {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--cyan);
  word-break: break-all;
}

/* Flex row: pattern value + toggle button side by side */
.pattern-value-row {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

/* Left pattern — violet; Right pattern — warm copper/brown */
#const-hpl { color: var(--violet); }
#const-hpr { color: #c07842; }

.constant-badges {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.badge {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  background: var(--bg-surface);
  border: 1px solid var(--border-dim);
  border-radius: 20px;
  padding: 3px 10px;
  font-size: 0.72rem;
  color: var(--text-secondary);
}
.badge.badge-lc  { border-color: var(--border); color: var(--text-secondary); }
.badge.badge-rpr { border-color: var(--border); color: var(--text-secondary); }

.active-indicator {
  margin-top: 14px;
  padding: 10px 14px;
  background: var(--violet-dim);
  border: 1px solid rgba(167, 139, 250, 0.25);
  border-radius: var(--radius-sm);
  font-size: 0.8rem;
}

.active-indicator-row {
  display: flex;
  gap: 24px;
  align-items: flex-start;
}

.active-indicator-col {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.active-indicator-label { color: var(--text-secondary); font-size: 0.7rem; margin-bottom: 2px; }

/* Active Constant value — violet, the assembled vpc string */
.active-indicator-value { color: var(--red); font-family: var(--font-mono); font-weight: 700; font-size: 1rem; }

/* Digital Root value — green, the number 1–9 that selected this constant */
.active-dr-value { color: var(--green); font-family: var(--font-mono); font-weight: 700; font-size: 1rem; }

/* ============================================================
   RESULT PANEL
   ============================================================ */
.result-panel {
  width: 100%;
}


.result-stats-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 20px;
  padding: 14px 20px;
  background: rgba(255,255,255,0.015);
  border-bottom: 1px solid var(--border-dim);
  align-items: center;
}

.stat-chip {
  display: flex;
  align-items: baseline;
  gap: 5px;
}

.stat-label {
  font-size: 0.68rem;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

.stat-value {
  font-family: var(--font-mono);
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--cyan);
}

.stat-value.timing { color: var(--amber); }
.stat-value.size   { color: var(--green); }

/* Result panel pattern row */
.result-patterns-row {
  display: flex;
  flex-wrap: wrap;
  gap: 24px;
  padding: 10px 20px;
  background: rgba(255,255,255,0.01);
  border-bottom: 1px solid var(--border-dim);
}
.result-pattern-item {
  display: flex;
  align-items: baseline;
  gap: 8px;
}

/* Result navigation */
.result-nav {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 12px 20px;
  border-bottom: 1px solid var(--border-dim);
  flex-wrap: wrap;
}

.nav-label {
  font-size: 0.72rem;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  flex-shrink: 0;
}

.nav-input {
  width: 100px;
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--text-primary);
  font-family: var(--font-mono);
  font-size: 0.8rem;
  padding: 5px 8px;
}
.nav-input:focus { outline: none; border-color: var(--cyan); }

.btn-nav {
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--text-secondary);
  font-size: 0.8rem;
  padding: 5px 12px;
  cursor: pointer;
  transition: all 0.15s;
  font-family: var(--font-sans);
}
.btn-nav:hover {
  border-color: var(--cyan);
  color: var(--cyan);
  background: var(--cyan-dim);
}

.panel-tabs {
  display: flex;
  gap: 4px;
}
.panel-tab {
  background: none;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--text-secondary);
  font-size: 0.8rem;
  padding: 4px 10px;
  cursor: pointer;
  font-family: var(--font-sans);
  transition: all 0.15s;
}
.panel-tab.active {
  border-color: var(--cyan);
  color: var(--cyan);
  background: var(--cyan-dim);
}
.panel-tab:hover:not(.active) {
  border-color: var(--border-bright);
  color: var(--text-primary);
}

.btn-stepper {
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--text-secondary);
  font-size: 1rem;
  font-family: var(--font-mono);
  padding: 0 8px;
  cursor: pointer;
  transition: all 0.15s;
  flex-shrink: 0;
  line-height: 1;
}
.btn-stepper:hover {
  border-color: var(--cyan);
  color: var(--cyan);
  background: var(--cyan-dim);
}

.increment-step {
  min-width: 36px;
  max-width: 80px;
  width: auto;
  text-align: center;
  color: var(--gold);
  background: var(--bg-input);
  border: 1px solid var(--gold);
  border-radius: var(--radius-sm);
  font-family: var(--font-mono);
  font-size: 0.8rem;
  font-weight: 600;
  padding: 0 4px;
  -moz-appearance: textfield;
}
.increment-step::-webkit-inner-spin-button,
.increment-step::-webkit-outer-spin-button { -webkit-appearance: none; }
.increment-step:focus {
  outline: none;
  border-color: var(--amber);
  box-shadow: 0 0 0 2px color-mix(in srgb, var(--amber) 25%, transparent);
}

.btn-download {
  margin-left: auto;
  background: var(--green-dim);
  border: 1px solid rgba(52, 211, 153, 0.25);
  border-radius: var(--radius-sm);
  color: var(--green);
  font-size: 0.8rem;
  padding: 5px 14px;
  cursor: pointer;
  text-decoration: none;
  transition: all 0.15s;
  font-family: var(--font-sans);
}
.btn-download:hover {
  background: var(--green-glow);
  border-color: var(--green);
  box-shadow: 0 0 8px var(--green-glow);
}

/* Number display */
/* ── Display mode toggle (Standard / Pyramid) ── */
.display-mode-bar {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 8px 20px;
  border-bottom: 1px solid var(--border-dim);
}

.display-mode-label {
  font-size: 0.68rem;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  flex-shrink: 0;
}

.display-mode-switch {
  display: flex;
  background: #0d1a2e;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  overflow: hidden;
}

.display-mode-btn {
  background: transparent;
  border: none;
  padding: 4px 14px;
  font-size: 0.72rem;
  font-family: var(--font-ui);
  color: var(--text-secondary);
  cursor: pointer;
  transition: background 0.15s, color 0.15s;
}

.display-mode-btn.active {
  background: #1e3a5f;
  color: var(--text-primary);
}

.display-mode-btn:hover:not(.active) {
  color: var(--text-primary);
  background: #152840;
}

.number-display-wrap {
  padding: 20px;
}

.number-display {
  background: var(--bg-surface);
  border: 1px solid var(--border-dim);
  border-radius: var(--radius);
  padding: 16px;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  line-height: 1.7;
  color: var(--green);
  min-height: 120px;
  max-height: 280px;
  overflow-y: auto;
  overflow-wrap: anywhere;
  word-break: break-all;
  white-space: pre-wrap;
  /* Terminal glow */
  box-shadow: inset 0 0 30px rgba(52, 211, 153, 0.03);
}

/* Pyramid display mode — container allows horizontal/vertical scroll */
.number-display.pyramid-mode {
  overflow-x: auto;
  overflow-y: auto;
  /* white-space is intentionally NOT overridden here — whitespace preservation
     is handled by the inner .pyramid-inner <pre> element via browser UA stylesheet */
}

/* Inner <pre> for pyramid layout.
   width: max-content makes the element as wide as its longest line, which
   causes the parent .number-display to scroll horizontally rather than wrap. */
.pyramid-inner {
  margin: 0;
  padding: 0;
  font: inherit;
  background: none;
  border: none;
  width: max-content;
  min-width: 100%;
}

/* VPC constant highlight inside result display */
.vpc-highlight {
  color: var(--red);
  font-weight: 700;
}

/* Pattern highlight colors — char-by-char match in pyramid view */
.hpl-match { color: var(--violet); }
.hpr-match { color: #c07842; }  /* matches #const-hpr warm copper/brown */

/* HPL / HPR toggle chip buttons in the constants panel */
.pattern-toggle {
  display: inline-flex;
  align-items: center;
  padding: 1px 7px;
  border-radius: 4px;
  border: 1px solid var(--border);
  background: transparent;
  color: var(--text-secondary);
  font: inherit;
  font-size: 0.68rem;
  cursor: pointer;
  transition: border-color 0.15s, background 0.15s, color 0.15s;
  margin-left: 0.4rem;
  vertical-align: middle;
}
.pattern-toggle:hover {
  border-color: var(--border-bright);
  color: var(--text-primary);
}
.pattern-toggle.active.hpl {
  background: var(--violet);
  border-color: var(--violet);
  color: #000;
}
.pattern-toggle.active.hpr {
  background: var(--amber);
  border-color: var(--amber);
  color: #000;
}

/* Custom scrollbar */
.number-display::-webkit-scrollbar { width: 6px; }
.number-display::-webkit-scrollbar-track { background: var(--bg-void); }
.number-display::-webkit-scrollbar-thumb {
  background: var(--border-bright);
  border-radius: 3px;
}

.result-placeholder {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  min-height: 180px;
  color: var(--text-muted);
  gap: 12px;
}

.result-placeholder-icon {
  font-size: 3rem;
  opacity: 0.2;
  filter: grayscale(1);
}

.result-placeholder-text {
  font-size: 0.85rem;
  text-align: center;
}

/* Error display */
.error-box {
  margin: 16px 20px;
  padding: 14px 16px;
  background: rgba(248, 113, 113, 0.08);
  border: 1px solid rgba(248, 113, 113, 0.3);
  border-radius: var(--radius);
  color: var(--red);
  font-size: 0.85rem;
  font-family: var(--font-mono);
}

/* Loading indicator */
.loading-bar {
  height: 2px;
  background: linear-gradient(90deg, transparent, var(--cyan), transparent);
  background-size: 200% 100%;
  animation: loading-sweep 1.2s linear infinite;
  display: none;
}
.htmx-request .loading-bar { display: block; }
@keyframes loading-sweep {
  0% { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}

/* ============================================================
   HISTORY TABLE
   ============================================================ */
.history-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.82rem;
}

.history-table th {
  text-align: left;
  color: var(--text-muted);
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  padding: 8px 14px;
  border-bottom: 1px solid var(--border);
}

.history-table td {
  padding: 9px 14px;
  border-bottom: 1px solid var(--border-dim);
  vertical-align: middle;
}

.history-table tr:last-child td { border-bottom: none; }
.history-table tbody tr:hover td { background: var(--bg-hover); }

.history-table td.mono {
  font-family: var(--font-mono);
  font-size: 0.78rem;
}

.method-badge {
  display: inline-block;
  padding: 2px 8px;
  border-radius: 4px;
  font-size: 0.7rem;
  font-family: var(--font-mono);
  font-weight: 600;
}
.method-badge.matrix  { background: var(--cyan-dim); color: var(--cyan); border: 1px solid rgba(56,191,248,0.2); }
.method-badge.formula { background: var(--gold-dim);  color: var(--gold); border: 1px solid rgba(232,183,64,0.2); }
.method-badge.stream  { background: var(--green-dim); color: var(--green); border: 1px solid rgba(52,211,153,0.2); }

.empty-state {
  text-align: center;
  padding: 32px;
  color: var(--text-muted);
  font-size: 0.82rem;
}

/* ============================================================
   LAB PANEL
   ============================================================ */
.lab-controls {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
  margin-bottom: 16px;
}

.btn-lab {
  display: flex;
  align-items: center;
  gap: 7px;
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--text-primary);
  font-family: var(--font-sans);
  font-size: 0.83rem;
  padding: 8px 16px;
  cursor: pointer;
  transition: all 0.15s;
}
.btn-lab:hover {
  border-color: var(--violet);
  color: var(--violet);
  background: var(--violet-dim);
  box-shadow: 0 0 10px var(--violet-glow);
}
.btn-lab.htmx-request {
  opacity: 0.6;
  cursor: wait;
}

.test-output {
  background: var(--bg-surface);
  border: 1px solid var(--border-dim);
  border-radius: var(--radius);
  padding: 16px;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  line-height: 1.8;
  max-height: 320px;
  overflow-y: auto;
  min-height: 60px;
}

.test-line { display: flex; align-items: baseline; gap: 8px; }
.test-line.passed .test-status  { color: var(--green); }
.test-line.failed .test-status  { color: var(--red); }
.test-line.xfail  .test-status  { color: var(--amber); }
.test-line.info   .test-status  { color: var(--text-muted); }
.test-line.summary { margin-top: 8px; padding-top: 8px; border-top: 1px solid var(--border-dim); color: var(--text-primary); font-weight: 600; }

.test-name { color: var(--text-secondary); }
.test-output-placeholder { color: var(--text-muted); padding: 8px 0; }

/* Result count badges */
.test-summary-badges { display: flex; gap: 8px; margin-top: 10px; }
.pass-count  { color: var(--green); font-weight: 700; }
.fail-count  { color: var(--red);   font-weight: 700; }
.xfail-count { color: var(--amber); font-weight: 700; }

/* ============================================================
   COLLAPSIBLE SECTION
   ============================================================ */
.collapse-toggle {
  display: flex;
  align-items: center;
  gap: 8px;
  cursor: pointer;
  user-select: none;
  width: 100%;
  background: none;
  border: none;
  text-align: left;
  color: inherit;
  font: inherit;
}

.collapse-arrow {
  font-size: 0.7rem;
  transition: transform 0.2s;
  color: var(--text-muted);
}
.collapse-toggle[aria-expanded="true"] .collapse-arrow { transform: rotate(90deg); }

.collapse-body {
  overflow: hidden;
  transition: max-height 0.3s var(--ease), opacity 0.2s;
}
.collapse-body.closed { max-height: 0; opacity: 0; }
.collapse-body.open   { max-height: 2000px; opacity: 1; }

/* ============================================================
   MISC UTILITIES
   ============================================================ */
.divider {
  height: 1px;
  background: var(--border-dim);
  margin: 4px 0;
}

.text-mono  { font-family: var(--font-mono); }
.text-cyan  { color: var(--cyan); }
.text-gold  { color: var(--gold); }
.text-green { color: var(--green); }
.text-muted { color: var(--text-muted); }
.text-sm    { font-size: 0.8rem; }

.flex-gap { display: flex; align-items: center; gap: 8px; }

/* Scrollbar global */
::-webkit-scrollbar { width: 6px; height: 6px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: var(--border-bright); border-radius: 3px; }

/* htmx fade-in for swapped elements */
.htmx-added { animation: fade-in 0.3s var(--ease); }
@keyframes fade-in {
  from { opacity: 0; transform: translateY(4px); }
  to   { opacity: 1; transform: translateY(0); }
}

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