:root {
  --bg: #080c14;
  --bg2: #0d1420;
  --bg3: #111827;
  --glass: rgba(255,255,255,0.04);
  --glass2: rgba(255,255,255,0.07);
  --border: rgba(99,179,237,0.15);
  --border2: rgba(99,179,237,0.3);
  --neon: #63b3ed;
  --neon2: #90cdf4;
  --accent: #7c3aed;
  --accent2: #a78bfa;
  --green: #10b981;
  --red: #ef4444;
  --amber: #f59e0b;
  --text: #e2e8f0;
  --muted: #64748b;
  --mono: 'Space Mono', monospace;
  --sans: 'DM Sans', sans-serif;
}
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--sans);
  min-height: 100vh;
  overflow-x: hidden;
}
/* Animated grid bg */
body::before {
  content: '';
  position: fixed;
  inset: 0;
  background-image:
    linear-gradient(rgba(99,179,237,0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(99,179,237,0.03) 1px, transparent 1px);
  background-size: 40px 40px;
  pointer-events: none;
  z-index: 0;
}
body::after {
  content: '';
  position: fixed;
  top: -200px; left: -200px;
  width: 600px; height: 600px;
  background: radial-gradient(circle, rgba(124,58,237,0.08) 0%, transparent 70%);
  pointer-events: none;
  z-index: 0;
  animation: orb 12s ease-in-out infinite alternate;
}
@keyframes orb { to { transform: translate(400px, 300px); } }

/* HEADER */
header {
  position: relative; z-index: 10;
  padding: 1.5rem 2rem;
  border-bottom: 1px solid var(--border);
  background: rgba(8,12,20,0.8);
  backdrop-filter: blur(20px);
  display: flex; align-items: center; justify-content: space-between;
}
.logo {
  display: flex; align-items: center; gap: 12px;
}
.logo-icon {
  width: 36px; height: 36px;
  border: 1.5px solid var(--neon);
  border-radius: 8px;
  display: flex; align-items: center; justify-content: center;
  box-shadow: 0 0 12px rgba(99,179,237,0.3), inset 0 0 12px rgba(99,179,237,0.05);
}
.logo-icon svg { width: 18px; height: 18px; }
.logo-text { font-family: var(--mono); font-size: 15px; color: var(--neon2); letter-spacing: 0.05em; }
.logo-sub { font-size: 11px; color: var(--muted); font-family: var(--mono); }
.header-badges { display: flex; gap: 8px; }
.badge {
  padding: 4px 10px;
  border-radius: 20px;
  font-size: 11px;
  font-family: var(--mono);
  border: 1px solid;
  letter-spacing: 0.05em;
}
.badge-blue { border-color: var(--neon); color: var(--neon); background: rgba(99,179,237,0.08); }
.badge-purple { border-color: var(--accent2); color: var(--accent2); background: rgba(124,58,237,0.08); }

/* MAIN LAYOUT */
.app { position: relative; z-index: 1; display: flex; flex-direction: column; gap: 0; }

/* SECTION WRAPPERS */
.section {
  padding: 1.5rem 2rem;
  border-bottom: 1px solid var(--border);
}
.section-title {
  font-family: var(--mono);
  font-size: 11px;
  color: var(--neon);
  letter-spacing: 0.15em;
  text-transform: uppercase;
  margin-bottom: 1rem;
  display: flex; align-items: center; gap: 8px;
}
.section-title::before {
  content: '';
  width: 3px; height: 14px;
  background: linear-gradient(to bottom, var(--neon), var(--accent));
  border-radius: 2px;
  box-shadow: 0 0 6px var(--neon);
}

/* GLASS CARD */
.glass-card {
  background: var(--glass);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 1.25rem;
  backdrop-filter: blur(10px);
  transition: border-color 0.2s, box-shadow 0.2s;
}
.glass-card:hover { border-color: var(--border2); box-shadow: 0 0 20px rgba(99,179,237,0.05); }

/* INPUT GRID */
.input-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 1rem; }
.input-group { display: flex; flex-direction: column; gap: 6px; }
.input-label { font-size: 11px; color: var(--muted); font-family: var(--mono); letter-spacing: 0.1em; }
.input-field {
  background: rgba(255,255,255,0.04);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 8px 12px;
  color: var(--text);
  font-family: var(--mono);
  font-size: 13px;
  outline: none;
  transition: border-color 0.2s, box-shadow 0.2s;
  width: 100%;
}
.input-field:focus {
  border-color: var(--neon);
  box-shadow: 0 0 12px rgba(99,179,237,0.15);
}
.input-field::placeholder { color: var(--muted); }

/* TRANSITION TABLE */
.tt-wrapper { overflow-x: auto; margin-top: 1rem; }
.trans-table {
  width: 100%;
  border-collapse: collapse;
  font-family: var(--mono);
  font-size: 12px;
}
.trans-table th {
  padding: 8px 12px;
  background: rgba(99,179,237,0.08);
  border: 1px solid var(--border);
  color: var(--neon);
  font-size: 11px;
  letter-spacing: 0.1em;
  text-align: center;
  white-space: nowrap;
}
.trans-table td {
  padding: 6px 8px;
  border: 1px solid var(--border);
  text-align: center;
}
.trans-table td input {
  background: transparent;
  border: none;
  color: var(--text);
  font-family: var(--mono);
  font-size: 12px;
  width: 60px;
  text-align: center;
  outline: none;
  transition: color 0.2s;
}
.trans-table td input:focus { color: var(--neon2); }
.state-label-cell {
  color: var(--neon);
  font-weight: 700;
  white-space: nowrap;
  padding: 6px 12px !important;
}

/* BUTTONS */
.btn {
  padding: 9px 18px;
  border-radius: 8px;
  font-family: var(--mono);
  font-size: 12px;
  cursor: pointer;
  border: 1px solid;
  transition: all 0.2s;
  letter-spacing: 0.05em;
  display: inline-flex; align-items: center; gap: 6px;
}
.btn-primary {
  background: rgba(99,179,237,0.1);
  border-color: var(--neon);
  color: var(--neon);
}
.btn-primary:hover { background: rgba(99,179,237,0.2); box-shadow: 0 0 16px rgba(99,179,237,0.3); transform: translateY(-1px); }
.btn-accent {
  background: rgba(124,58,237,0.15);
  border-color: var(--accent2);
  color: var(--accent2);
}
.btn-accent:hover { background: rgba(124,58,237,0.25); box-shadow: 0 0 16px rgba(167,139,250,0.3); transform: translateY(-1px); }
.btn-green {
  background: rgba(16,185,129,0.1);
  border-color: var(--green);
  color: var(--green);
}
.btn-green:hover { background: rgba(16,185,129,0.2); box-shadow: 0 0 16px rgba(16,185,129,0.3); transform: translateY(-1px); }
.btn-red {
  background: rgba(239,68,68,0.1);
  border-color: var(--red);
  color: var(--red);
}
.btn-red:hover { background: rgba(239,68,68,0.2); }
.btn:disabled { opacity: 0.4; cursor: not-allowed; transform: none !important; box-shadow: none !important; }
.btn-sm { padding: 6px 12px; font-size: 11px; }

/* ALGO SELECTOR */
.algo-pills { display: flex; gap: 10px; flex-wrap: wrap; }
.algo-pill {
  padding: 8px 16px;
  border-radius: 20px;
  border: 1px solid var(--border);
  font-family: var(--mono);
  font-size: 12px;
  cursor: pointer;
  transition: all 0.2s;
  color: var(--muted);
  background: var(--glass);
}
.algo-pill:hover { border-color: var(--border2); color: var(--text); }
.algo-pill.active {
  border-color: var(--neon);
  color: var(--neon);
  background: rgba(99,179,237,0.1);
  box-shadow: 0 0 12px rgba(99,179,237,0.15);
}

/* ACTION BAR */
.action-bar {
  padding: 1rem 2rem;
  display: flex; align-items: center; gap: 12px; flex-wrap: wrap;
  border-bottom: 1px solid var(--border);
  background: rgba(8,12,20,0.6);
}

/* 3-PANEL VISUALIZATION */
.viz-container {
  display: grid;
  grid-template-columns: 1fr 1.2fr 1fr;
  gap: 1px;
  background: var(--border);
  min-height: 380px;
}
.viz-panel {
  background: var(--bg2);
  position: relative;
  min-height: 380px;
}
.viz-panel-header {
  padding: 10px 14px;
  border-bottom: 1px solid var(--border);
  display: flex; align-items: center; justify-content: space-between;
  background: rgba(0,0,0,0.3);
}
.viz-panel-title {
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.15em;
  text-transform: uppercase;
}
.viz-panel-title.blue { color: var(--neon); }
.viz-panel-title.purple { color: var(--accent2); }
.viz-panel-title.green { color: var(--green); }
.cy-container { width: 100%; height: 320px; }
#algo-center { width: 100%; height: 320px; overflow-y: auto; padding: 1rem; }

/* STEP PANEL */
.step-panel {
  padding: 1.25rem 2rem;
  border-bottom: 1px solid var(--border);
  background: rgba(8,12,20,0.5);
}
.step-nav { display: flex; align-items: center; gap: 12px; margin-bottom: 1rem; }
.step-counter {
  font-family: var(--mono);
  font-size: 12px;
  color: var(--muted);
  min-width: 80px;
}
.step-progress {
  flex: 1;
  height: 3px;
  background: rgba(255,255,255,0.06);
  border-radius: 2px;
  overflow: hidden;
}
.step-progress-bar {
  height: 100%;
  background: linear-gradient(90deg, var(--neon), var(--accent2));
  border-radius: 2px;
  transition: width 0.4s cubic-bezier(0.4,0,0.2,1);
  box-shadow: 0 0 8px rgba(99,179,237,0.4);
}
.step-content {
  background: var(--glass);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 1rem 1.25rem;
  min-height: 80px;
  transition: all 0.3s;
}
.step-title {
  font-family: var(--mono);
  font-size: 12px;
  color: var(--neon);
  margin-bottom: 6px;
}
.step-desc { font-size: 14px; color: var(--text); line-height: 1.6; }

/* TABLE FILLING MATRIX */
.matrix-grid {
  display: grid;
  gap: 3px;
}
.matrix-cell {
  width: 36px; height: 36px;
  border-radius: 6px;
  border: 1px solid var(--border);
  display: flex; align-items: center; justify-content: center;
  font-family: var(--mono);
  font-size: 10px;
  transition: all 0.4s;
  background: var(--glass);
}
.matrix-cell.marked { background: rgba(239,68,68,0.2); border-color: var(--red); color: var(--red); }
.matrix-cell.equiv { background: rgba(16,185,129,0.2); border-color: var(--green); color: var(--green); }
.matrix-cell.checking { background: rgba(245,158,11,0.2); border-color: var(--amber); color: var(--amber); animation: pulse 0.8s ease-in-out 2; }
.matrix-cell.header { background: rgba(99,179,237,0.08); color: var(--neon); border-color: rgba(99,179,237,0.2); }
@keyframes pulse { 0%,100%{opacity:1} 50%{opacity:0.5} }

/* PARTITION DISPLAY */
.partition-group {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 6px 10px;
  border-radius: 20px;
  margin: 3px;
  font-family: var(--mono);
  font-size: 12px;
  border: 1px solid;
  transition: all 0.4s;
}
.partition-final { border-color: var(--green); color: var(--green); background: rgba(16,185,129,0.1); }
.partition-non-final { border-color: var(--neon); color: var(--neon); background: rgba(99,179,237,0.08); }
.partition-split { border-color: var(--amber); color: var(--amber); background: rgba(245,158,11,0.1); animation: pulse 0.6s ease-in-out 2; }

/* COMPARISON */
.comparison-bar {
  padding: 1rem 2rem;
  border-bottom: 1px solid var(--border);
  display: flex; align-items: center; gap: 24px; flex-wrap: wrap;
  background: rgba(16,185,129,0.04);
}
.comp-stat {
  display: flex; flex-direction: column; gap: 2px;
}
.comp-stat-label { font-size: 11px; color: var(--muted); font-family: var(--mono); }
.comp-stat-value { font-size: 20px; font-family: var(--mono); color: var(--green); }
.arrow-anim {
  font-size: 18px;
  color: var(--muted);
  animation: arrowSlide 1.5s ease-in-out infinite;
}
@keyframes arrowSlide { 0%,100%{transform:translateX(0)} 50%{transform:translateX(4px)} }

/* STRING SIMULATOR */
.sim-section { padding: 1.25rem 2rem; border-bottom: 1px solid var(--border); }
.sim-track {
  display: flex;
  gap: 4px;
  margin: 0.75rem 0;
  flex-wrap: wrap;
  align-items: center;
}
.sim-char {
  width: 34px; height: 34px;
  border-radius: 6px;
  border: 1px solid var(--border);
  display: flex; align-items: center; justify-content: center;
  font-family: var(--mono);
  font-size: 14px;
  transition: all 0.3s;
}
.sim-char.active { border-color: var(--amber); background: rgba(245,158,11,0.2); color: var(--amber); box-shadow: 0 0 10px rgba(245,158,11,0.3); transform: scale(1.1); }
.sim-char.visited { border-color: var(--green); color: var(--green); background: rgba(16,185,129,0.1); }
.sim-result {
  padding: 8px 16px;
  border-radius: 8px;
  font-family: var(--mono);
  font-size: 13px;
  display: inline-flex; align-items: center; gap: 8px;
}
.sim-accept { background: rgba(16,185,129,0.15); border: 1px solid var(--green); color: var(--green); }
.sim-reject { background: rgba(239,68,68,0.15); border: 1px solid var(--red); color: var(--red); }

/* WARNINGS */
.warning-list { display: flex; flex-direction: column; gap: 6px; margin-top: 8px; }
.warning-item {
  padding: 8px 12px;
  border-radius: 6px;
  font-size: 13px;
  display: flex; align-items: center; gap: 8px;
  font-family: var(--mono);
}
.warning-error { background: rgba(239,68,68,0.1); border: 1px solid rgba(239,68,68,0.3); color: #fca5a5; }
.warning-warn { background: rgba(245,158,11,0.1); border: 1px solid rgba(245,158,11,0.3); color: #fcd34d; }
.warning-info { background: rgba(99,179,237,0.1); border: 1px solid rgba(99,179,237,0.2); color: var(--neon2); }

/* EXPORT */
.export-bar {
  padding: 1rem 2rem;
  display: flex; gap: 10px; align-items: center; flex-wrap: wrap;
}

/* 3D CANVAS */
#three-canvas-container {
  display: none;
  position: relative;
}
#three-canvas-container.active { display: block; }
#threeCanvas { width: 100% !important; height: 380px !important; }

/* TOOLTIP */
.tooltip {
  position: fixed;
  background: rgba(13,20,32,0.95);
  border: 1px solid var(--border2);
  border-radius: 8px;
  padding: 8px 12px;
  font-family: var(--mono);
  font-size: 11px;
  color: var(--neon2);
  pointer-events: none;
  z-index: 1000;
  display: none;
  backdrop-filter: blur(10px);
}

/* MODE TABS */
.mode-tabs { display: flex; gap: 0; border: 1px solid var(--border); border-radius: 8px; overflow: hidden; }
.mode-tab {
  padding: 7px 16px;
  font-family: var(--mono);
  font-size: 12px;
  cursor: pointer;
  border: none;
  background: transparent;
  color: var(--muted);
  transition: all 0.2s;
  flex: 1;
  text-align: center;
}
.mode-tab.active { background: rgba(99,179,237,0.12); color: var(--neon); }
.mode-tab:hover:not(.active) { color: var(--text); background: var(--glass); }

/* CANVAS DRAW */
#draw-canvas {
  background: var(--glass);
  border: 1px solid var(--border);
  border-radius: 8px;
  cursor: crosshair;
  display: block;
}

/* SCROLLBAR */
::-webkit-scrollbar { width: 5px; height: 5px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: var(--border2); border-radius: 3px; }

/* RESPONSIVE */
@media(max-width:900px) {
  .viz-container { grid-template-columns: 1fr; }
  .input-grid { grid-template-columns: 1fr; }
}

/* ANIMATIONS */
@keyframes fadeIn { from{opacity:0;transform:translateY(8px)} to{opacity:1;transform:translateY(0)} }
.fade-in { animation: fadeIn 0.3s ease forwards; }

/* GLOW PULSE for active state */
@keyframes glowPulse { 0%,100%{box-shadow:0 0 8px rgba(99,179,237,0.2)} 50%{box-shadow:0 0 20px rgba(99,179,237,0.4)} }

.presets { display: flex; gap: 6px; margin-top: 8px; flex-wrap: wrap; }
.preset-btn {
  padding: 4px 10px;
  border-radius: 20px;
  border: 1px solid var(--border);
  background: var(--glass);
  color: var(--muted);
  font-family: var(--mono);
  font-size: 10px;
  cursor: pointer;
  transition: all 0.2s;
}
.preset-btn:hover { border-color: var(--neon); color: var(--neon); }

.section-cols { display: flex; gap: 1rem; flex-wrap: wrap; }
.section-col { flex: 1; min-width: 240px; }
.inline-flex { display: flex; gap: 8px; align-items: center; flex-wrap: wrap; }

#draw-toolbar { display: flex; gap: 6px; margin-bottom: 8px; }
.draw-tool { padding: 5px 10px; border-radius: 6px; border: 1px solid var(--border); background: var(--glass); color: var(--muted); font-family: var(--mono); font-size: 11px; cursor: pointer; transition: all 0.2s; }
.draw-tool.active { border-color: var(--neon); color: var(--neon); background: rgba(99,179,237,0.08); }

.partition-step { margin-bottom: 1rem; }
.partition-step-label { font-family: var(--mono); font-size: 10px; color: var(--muted); margin-bottom: 4px; letter-spacing: 0.1em; }

.equiv-info {
  background: rgba(16,185,129,0.06);
  border: 1px solid rgba(16,185,129,0.2);
  border-radius: 8px;
  padding: 10px 14px;
  font-size: 12px;
  font-family: var(--mono);
  color: var(--green);
  margin-top: 8px;
}



.footer {
  border-top: 1px solid var(--border);
  padding: 14px 20px;
  background: rgba(5, 29, 76, 0.9);
  backdrop-filter: blur(10px);
}

.footer-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  font-family: var(--mono);
  font-size: 11px;
  color: var(--muted);
}

.footer-left b {
  color: var(--neon);
}

.footer-center svg {
  transition: transform 0.2s;
}

.footer-center svg:hover {
  transform: scale(1.2);
  filter: drop-shadow(0 0 6px #63b3ed);
}

.footer-right {
  color: var(--accent2);
}

.matrix-label {
    font-size: 11px;
    font-family: monospace;
    color: #cbd5f5;

    /* 🔥 FIX */
    white-space: normal;
    word-break: break-word;
    max-width: 90px;
    text-align: center;
    line-height: 1.2;
}

.matrix-cell {
    padding: 6px;
    min-width: 50px;

    /* 🔥 FIX */
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;

    white-space: normal;
    word-break: break-word;
}






.home {
  padding: 40px;
  display: flex;
  flex-direction: column;
  align-items: center;
}

/* HERO */
.hero {
  text-align: center;
  margin-bottom: 40px;
}

.glow {
  font-size: 36px;
  color: #63b3ed;
  text-shadow: 0 0 20px rgba(99,179,237,0.6);
}

.subtitle {
  color: var(--muted);
  margin: 10px 0 20px;
}

/* GRID */
.grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
  max-width: 1000px;
  width: 100%;
}

.card {
  background: rgba(15, 23, 42, 0.6);
  border: 1px solid rgba(99,179,237,0.2);
  padding: 18px;
  border-radius: 16px;
  backdrop-filter: blur(12px);
  transition: 0.3s;
}

.card:hover {
  transform: translateY(-5px) scale(1.02);
  box-shadow: 0 0 20px rgba(99,179,237,0.2);
}

.card h2 {
  color: #63b3ed;
  margin-bottom: 10px;
}

.card ul, .card ol {
  padding-left: 18px;
}

.card.wide {
  grid-column: span 2;
}

/* BUTTON */
.start-btn {
  padding: 14px 28px;
  border-radius: 12px;
  border: none;
  font-size: 16px;
  cursor: pointer;
  background: linear-gradient(135deg, #63b3ed, #10b981);
  color: white;
  transition: 0.3s;
}

.start-btn:hover {
  transform: scale(1.08);
  box-shadow: 0 0 20px rgba(99,179,237,0.5);
}